Reappraisals of biological behaviors of PDGFRA mutant gastrointestinal stromal tumor / 中华病理学杂志

Objective: To investigate the biological behavior spectrum of platelet-derived growth factor alpha receptor (PDGFRA)-mutant gastrointestinal stromal tumor (GIST), and to compare the clinical values of the Zhongshan method of benign and malignant evaluation with the modified National Institutes of Health (NIH) risk stratification. Methods: A total of 119 cases of GIST with PDGFRA mutation who underwent surgical resection at Zhongshan Hospital, Fudan University from 2009 to 2020 were collected. The clinicopathological data, follow-up records, and subsequent treatment were reviewed and analyzed statistically. Results: There were 79 males and 40 females. The patients ranged in age from 25 to 80 years, with a median age of 60 years. Among them, 115 patients were followed up for 1-154 months, and 13 patients progressed to disease. The 5-year disease-free survival (DFS) and overall survival (OS) were 90.1% and 94.1%, respectively. According to the modified NIH risk stratification, 8 cases, 32 cases, 38 cases, and 35 cases were very-low risk, low risk, intermediate risk, and high risk, and 5-year DFS were 100.0%, 95.6%, 94.3%, and 80.5%, respectively. There was no significant difference in prognosis among the non-high risk groups, only the difference between high risk and non-high risk groups was significant (P=0.029). However, the 5-year OS was 100.0%, 100.0%, 95.0% and 89.0%, and there was no difference (P=0.221). According to the benign and malignant evaluation Zhongshan method, 43 cases were non-malignant (37.4%), 56 cases were low-grade malignant (48.7%), 9 cases were moderately malignant (7.8%), and 7 cases were highly malignant (6.1%). The 5-year DFS were 100.0%, 91.7%, 77.8%, 38.1%, and the difference was significant (P<0.001). The 5-year OS were 100.0%, 97.5%, 77.8%, 66.7%, the difference was significant (P<0.001). Conclusions: GIST with PDGFRA gene mutation shows a broad range of biological behavior, ranging from benign to highly malignant. According to the Zhongshan method, non-malignant and low-grade malignant tumors are common, the prognosis after surgery is good, while the fewer medium-high malignant tumors showed poor prognosis after surgical resection. The overall biological behavior of this type of GIST is relatively inert, which is due to the low proportion of medium-high malignant GIST. The modified NIH risk stratification may not be effective in risk stratification for PDGFRA mutant GIST.

Clinicopathological features and prognostic factors of gastric intermediate-risk gastrointestinal stromal tumor after surgical resection: a retrospective study / 中华病理学杂志

Objective: To investigate the clinicopathological features, treatment and prognosis of gastric intermediate-risk gastrointestinal stromal tumor (GIST), so as to provide a reference for clinical management and further research. Methods: A retrospective observational study of patients with gastric intermediate-risk GIST, who underwent surgical resection between January 1996 and December 2019 at Zhongshan Hospital of Fudan University, was carried out. Results: Totally, 360 patients with a median age of 59 years were included. There were 190 males and 170 females with median tumor diameter of 5.9 cm. Routine genetic testing was performed in 247 cases (68.6%, 247/360), and 198 cases (80.2%) showed KIT mutation, 26 cases (10.5%) showed PDGFRA mutation, and 23 cases were wild-type GIST. According to "Zhongshan Method"(including 12 parameters), there were 121 malignant and 239 non-malignant cases. Complete follow-up data were available in 241 patients; 55 patients (22.8%) received imatinib therapy, 10 patients (4.1%) experienced tumor progression, and one patient (PDGFRA mutation, 0.4%) died. Disease-free survival (DFS) and overall survival rate at 5 years was 96.0% and 99.6%, respectively. Among the intermediate-risk GIST, there was no difference in DFS between the overall population, KIT mutation, PDGFRA mutation, wild-type, non-malignant and malignant subgroups (all P>0.05). However, the non-malignancy/malignancy analysis showed that there were significant differences in DFS among the overall population (P<0.01), imatinib treatment group (P=0.044) and no imatinib treatment group (P<0.01). Adjuvant imatinib resulted in potential survival benefit for KIT mutated malignant and intermediate-risk GIST in DFS (P=0.241). Conclusions: Gastric intermediate-risk GIST shows a heterogeneous biologic behavior spectrum from benign to highly malignant. It can be further classified into benign and malignant, mainly nonmalignant and low-grade malignant. The overall disease progression rate after surgical resection is low, and real-world data show that there is no significant benefit from imatinib treatment after surgery. However, adjuvant imatinib potentially improves DFS of intermediate-risk patients with tumors harboring KIT mutation in the malignant group. Therefore, a comprehensive analysis of gene mutations in benign/malignant GIST will facilitate improvements in therapeutic decision-making.

Differences in clinicopathological features, gene mutations, and prognosis between primary gastric and intestinal gastrointestinal stromal tumors in 1061 patients / 中华胃肠外科杂志

Objective: To analyze the clinicopathological features and gene mutations of primary gastrointestinal stromal tumors (GISTs) of the stomach and intestine and the prognosis of intermediate- and high-risk GISTs. Methods: This was a retrospective cohort study. Data of patients with GISTs admitted to Tianjin Medical University Cancer Institute and Hospital from January 2011 to December 2019 were collected retrospectively. Patients with primary gastric or intestinal disease who had undergone endoscopic or surgical resection of the primary lesion and were confirmed pathologically as GIST were included. Patients treated with targeted therapy preoperatively were excluded. The above criteria were met by 1061 patients with primary GISTs, 794 of whom had gastric GISTs and 267 intestinal GISTs. Genetic testing had been performed in 360 of these patients since implementation of Sanger sequencing in our hospital in October 2014. Gene mutations in KIT exons 9, 11, 13, and 17 and PDGFRA exons 12 and 18 were detected by Sanger sequencing. The factors investigated in this study included: (1) clinicopathological data, such as sex, age, primary tumor location, maximum tumor diameter, histological type, mitotic index (/5 mm2), and risk classification; (2) gene mutation; (3) follow-up, survival, and postoperative treatment; and (4) prognostic factors of progression-free survival (PFS) and overall survival (OS) for intermediate- and high-risk GIST. Results: (1) Clinicopathological features: The median ages of patients with primary gastric and intestinal GIST were 61 (8-85) years and 60 (26-80) years, respectively; The median maximum tumor diameters were 4.0 (0.3-32.0) cm and 6.0 (0.3-35.0) cm, respectively; The median mitotic indexes were 3 (0-113)/5 mm² and 3 (0-50)/5 mm², respectively; The median Ki-67 proliferation indexes were 5% (1%-80%) and 5% (1%-50%), respectively. The rates of positivity for CD117, DOG-1, and CD34 were 99.7% (792/794), 99.9% (731/732), 95.6% (753/788), and 100.0% (267/267), 100.0% (238/238), 61.5% (163/265), respectively. There were higher proportions of male patients (χ²=6.390, P=0.011), tumors of maximum diameter > 5.0 cm (χ²=33.593, P<0.001), high-risk (χ²=94.957, P<0.001), and CD34-negativity (χ²=203.138, P<0.001) among patients with intestinal GISTs than among those with gastric GISTs. (2) Gene mutations: Gene mutations were investigated in 286/360 patients (79.4%) with primary gastric GISTs and 74/360 (20.6%) with primary intestinal GISTs. Among the 286 patients with gastric primary GISTs, 79.4% (227/286), 8.4% (24/286), and 12.2% (35/286), had KIT mutations, PDGFRA mutations, and wild-type, respectively. Among the 74 patients with primary intestinal GISTs, 85.1% (63/74) had KIT mutations and 14.9% (11/74) were wild-type. The PDGFRA mutation rate was lower in patients with intestinal GISTs than in those with gastric GISTs[ 0% vs. 8.4%(24/286), χ²=6.770, P=0.034], whereas KIT exon 9 mutations occurred more often in those with intestinal GISTs [22.2% (14/63) vs. 1.8% (4/227), P<0.001]. There were no significant differences between gastric and intestinal GISTs in the rates of KIT exon 11 mutation type and KIT exon 11 deletion mutation type (both P>0.05). (3) Follow-up, survival, and postoperative treatment: After excluding 228 patients with synchronous and metachronous other malignant tumors, the remaining 833 patients were followed up for 6-124 (median 53) months with a follow-up rate of 88.6% (738/833). None of the patients with very low or low-risk gastric (n=239) or intestinal GISTs (n=56) had received targeted therapy postoperatively. Among 179 patients with moderate-risk GISTs, postoperative targeted therapy had been administered to 88/155 with gastric and 11/24 with intestinal GISTs. Among 264 patients with high-risk GISTs, postoperative targeted therapy had been administered to 106/153 with gastric and 62/111 with intestinal GISTs. The 3-, 5-, and 10-year PFS of patients with gastric or intestinal GISTs were 96.5%, 93.8%, and 87.6% and 85.7%, 80.1% and 63.3%, respectively (P<0.001). The 3-, 5-, and 10-year OS were 99.2%, 98.8%, 97.5% and 94.8%, 92.1%, 85.0%, respectively (P<0.001). (4) Analysis of predictors of intermediate- and high-risk GISTs: The 5-year PFS of patients with gastric and intestinal GISTs were 89.5% and 73.2%, respectively (P<0.001); The 5-year OS were 97.9% and 89.3%, respectively (P<0.001). Multivariate analysis showed that high risk (HR=2.918, 95%CI: 1.076-7.911, P=0.035) and Ki-67 proliferation index > 5% (HR=2.778, 95%CI: 1.389-5.558, P=0.004) were independent risk factors for PFS in patients with intermediate- and high-risk GISTs (both P<0.05). Intestinal GISTs (HR=3.485, 95%CI: 1.407-8.634, P=0.007) and high risk (HR=3.753,95%CI:1.079-13.056, P=0.038) were independent risk factors for OS in patients with intermediate- and high-risk GISTs (both P<0.05). Postoperative targeted therapy was independent protective factor for PFS and OS (HR=0.103, 95%CI: 0.049-0.213, P<0.001; HR=0.210, 95%CI:0.078-0.564,P=0.002). Conclusions: Primary intestinal GIST behaves more aggressively than gastric GISTs and more frequently progress after surgery. Moreover, CD34 negativity and KIT exon 9 mutations occur more frequently in patients with intestinal GISTs than in those with gastric GISTs.

Clinicopathological characteristics and prognosis of patients with small bowel tumors: A single center analysis of 220 cases / 中华胃肠外科杂志

Objective: To analyze the clinicopathological characteristics and prognosis of patients with small bowel tumors. Methods: This was a retrospective, observational study. We collected clinicopathological data of patients with primary jejunal or ileal tumors who had undergone small bowel resection in the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University between January 2012 and September 2017. The inclusion criteria included: (1) older than 18 years; (2) had undergone small bowel resection; (3) primary location at jejunum or ileum; (4) postoperative pathological examination confirmed malignancy or malignant potential; and (5) complete clinicopathological and follow-up data. Patients with a history of previous or other concomitant malignancies and those who had undergone exploratory laparotomy with biopsy but no resection were excluded. The clinicopathological characteristics and prognoses of included patients were analyzed. Results: The study cohort comprised 220 patients with small bowel tumors, 136 of which were classified as gastrointestinal stromal tumors (GISTs), 47 as adenocarcinomas, and 35 as lymphomas. The median follow-up for all patient was 81.0 months (75.9-86.1). GISTs frequently manifested as gastrointestinal bleeding (61.0%, 83/136) and abdominal pain (38.2%, 52/136). In the patients with GISTs, the rates of lymph node and distant metastasis were 0.7% (1/136) and 11.8% (16/136), respectively. The median follow-up time was 81.0 (75.9-86.1) months. The 3-year overall survival (OS) rate was 96.3%. Multivariate Cox regression-analysis results showed that distant metastasis was the only factor associated with OS of patients with GISTs (HR=23.639, 95% CI: 4.564-122.430, P<0.001). The main clinical manifestations of small bowel adenocarcinoma were abdominal pain (85.1%, 40/47), constipation/diarrhea (61.7%, 29/47), and weight loss (61.7%, 29/47). Rates of lymph node and distant metastasis in patients with small bowel adenocarcinoma were 53.2% (25/47) and 23.4% (11/47), respectively. The 3-year OS rate of patients with small bowel adenocarcinoma was 44.7%. Multivariate Cox regression-analysis results showed that distant metastasis (HR=4.018, 95%CI: 2.108-10.331, P<0.001) and adjuvant chemotherapy (HR=0.291, 95% CI: 0.140-0.609, P=0.001) were independently associated with OS of patients with small bowel adenocarcinoma. Small bowel lymphoma frequently manifested as abdominal pain (68.6%, 24/35) and constipation/diarrhea (31.4%, 11/35); 77.1% (27/35) of small bowel lymphomas were of B-cell origin. The 3-year OS rate of patients with small bowel lymphomas was 60.0%. T/NK cell lymphomas (HR= 6.598, 95% CI: 2.172-20.041, P<0.001) and adjuvant chemotherapy (HR=0.119, 95% CI: 0.015-0.925, P=0.042) were independently associated with OS of patients with small bowel lymphoma. Small bowel GISTs have a better prognosis than small intestinal adenocarcinomas (P<0.001) or lymphomas (P<0.001), and small bowel lymphomas have a better prognosis than small bowel adenocarcinomas (P=0.035). Conclusions: The clinical manifestations of small intestinal tumor are non-specific. Small bowel GISTs are relatively indolent and have a good prognosis, whereas adenocarcinomas and lymphomas (especially T/NK-cell lymphomas) are highly malignant and have a poor prognosis. Adjuvant chemotherapy would likely improve the prognosis of patients with small bowel adenocarcinomas or lymphomas.

Clinical significance of pathological diagnosis and genetic abnormalities detection in gastrointestinal stromal tumor using endoscopic biopsy / 中华病理学杂志

Objective: To investigate the clinical significance of pathological diagnosis and genetic abnormalities detection of gastrointestinal stromal tumor (GIST) using endoscopic biopsy. Methods: Patients with GIST diagnosed by endoscopic biopsy (from January 1st, 2016 to August 1st, 2018, at Zhongshan Hospital, Fudan University) were included in this study. This retrospective study evaluated the histopathologic and immunohistochemical (IHC) features, genetic abnormalities of the tumors and the treatment and clinical course of the patients. Results: Totally 4 095 cases of GIST were collected, among which 67 patients (67/4 095, 1.6%) underwent endoscopic biopsy. Forty-eight patients (71.6%) were male and 19 (28.4%) were female, with a mean age of 61 years (range 31-90 years). Fifty-nine lesions were located in stomach and eight in duodenum. Of all the 67 cases, 47 were spindle type, 14 were epithelioid type, and 6 mixed type. IHC staining showed the positive rates were 100.0% (64/64) for DOG1, 98.4% (62/63) for CD117, 87.5% (56/64) for CD34, 3.6% (2/56) for S-100 protein, 12.1% (7/58) for α-SMA, 12.3% (7/57) for desmin and 4.0% (2/50) for CKpan. Morphologically, 34 cases were malignant; three cases (all epithelioid type) were originally misdiagnosed as poorly differentiated carcinoma; missed-diagnosis were found in four cases (spindle type) due to the insufficient diagnostic tumor cells. The genetic abnormality detection rate in the biopsy tissue was 38.8% (26/67),among them two patients were lost to follow up after biopsy, 33 patients received surgical resection, 16 cases underwent operation after neoadjuvant therapy and 16 patients with advanced disease underwent continuous imatinib therapy, with the genetic testing rate of 6.1% (2/33), 10/16 and 14/16, respectively. Conclusions: Endoscopic biopsy is a useful but rare method for the preoperative diagnosis of GIST. For majority of biopsy, accurate pathological diagnosis and auxiliary examination can be completed to guide clinical treatment. A thorough history in combination with endoscopic finding is essential to avoid misdiagnosis (epithelioid type) and missed diagnosis (spindle type) in suspicious cases. Genetic testing should be recommended in patients who will undergo targeted therapy after endoscopic biopsy, and it can provide valuable information and guidance for clinical treatment.

Research status and prospect of immunotherapy in gastrointestinal stromal tumors / 中华胃肠外科杂志

Tyrosine kinase inhibitors (TKI) significantly reduce the risk of recurrence and metastasis and prolong survival in patients with gastrointestinal stromal tumors (GIST), but drug resistance is often inevitable. Immunotherapy has been proven effective in multiple solid tumors, but the efficacy in GIST is unclear. The efficacy of immunotherapy depends on the tumor microenvironment (TME). Tumor-infiltrating immune cells and immune checkpoints are important components of TME, which not only participate in the regulation of tumor immune response but are also the key target of immunotherapy. A comprehensive analysis of them can clarify the mechanism of tumor immune escape. This review found that there are abundant tumor-infiltrating immune cells in GIST, which play an important role in tumor immune surveillance and escape. Although early clinical studies have shown that patients with GIST have a good tolerance to immunotherapy, the curative effect is not satisfactory. Therefore, how to select the responders of immunotherapy and coordinate the relationship between immunotherapy and TKIs is the key issue to be explored. At the same time, the gradual deepening of basic research and large sample prospective clinical trials will certainly provide more strategies for the application of immunotherapy in GIST.

Gastrointestinal Stromal Tumor in a Patient with Neurofibromatosis Type I: Diagnosis after Intestinal Occlusion Secondary to Adhesions after an Episode of Pancreatitis / Tumor Estromal Gastrointestinal em Paciente com Neurofibromatose Tipo I: Diagnóstico após Oclusão Intestinal Secundária a Aderências após Episódio de Pancreatite / Tumor del Estroma Gastrointestinal en Paciente con Neurofibromatosis Tipo I: Diagnóstico tras Oclusión Intestinal Secundaria a Adherencias tras Episodio de Pancreatitis

Introduction: Gastrointestinal stromal tumors (GIST), although relatively rare, account for 80% of mesenchymal tumors of the digestive tract. They manifest in any part of the alimentary tract and are derived from Cajal cells. They may occur sporadically or be associated with familial syndromes such as neurofibromatosis type I. The clinical picture is variable, and they are often diagnosed incidentally. The diagnosis requires imaging tests associated with histopathological and immunohistochemical analysis. The best strategy for treatment is surgical resection and cases should be analyzed individually to verify additional advantages with the association of systemic therapy. This study aims to present an unusual case of GIST associated with neurofibromatosis type I in a patient with incidental diagnosis after semi-intestinal occlusion secondary to an episode of pancreatitis, in addition to performing a literature review on the subject. Case report: A 49-year-old woman with a history of severe pancreatitis presented with intestinal obstruction approximately 8 months after this episode. Abdominal computed tomography revealed a heterogeneous formation in the mesogastric region, measuring 6.6 x 5.1 x 5.3 cm. She underwent surgical resection and histopathological and immunohistochemical studies confirmed the diagnosis of GIST. Six months after diagnosis, the patient is in good general condition and is on systemic therapy. Conclusion: GIST are rare tumors, but their diagnosis should come to mind in patients with neurofibromatosis type 1 with abdominal masses

Introdução: Os tumores do estroma gastrointestinal (GIST), embora relativamente raros, correspondem a 80% dos tumores mesenquimais do trato digestivo. Manifestam-se em qualquer parte do trato alimentar e são derivados das células de Cajal. Podem ocorrer de forma esporádica ou associados a síndromes familiares como a neurofibromatose tipo I. O quadro clínico é variável, sendo frequentemente diagnosticados de forma incidental. O diagnóstico requer realização de exames de imagem associados à análise histopatológica e imuno-histoquímica. A melhor estratégia para o tratamento é a ressecção cirúrgica e os casos devem ser analisados individualmente para verificar vantagens adicionais com a associação da terapia sistêmica. O objetivo deste trabalho é apresentar um caso incomum de GIST associado à neurofibromatose tipo I em uma paciente com diagnóstico incidental após semioclusão intestinal secundárias a episódio de pancreatite, além de realizar revisão de literatura sobre o assunto. Relato do caso: Mulher, 49 anos de idade,com passado de pancreatite grave,apresentou quadro de oclusão intestinal cerca de oito meses após esse episódio. A tomografia computadorizada de abdome revelou formação heterogênea em região mesogástrica, medindo 6,6 x 5,1 x 5,3 cm. Foi submetida à ressecção cirúrgica, e os estudos histopatológico e imuno-histoquímico corroboraram o diagnóstico de GIST. Seis meses após o diagnóstico, a paciente encontra-se em bom estado geral e em uso de terapia sistêmica. Conclusão: Os GIST são tumores raros, porémseu diagnóstico deve ser lembrado em pacientes com neurofibromatose tipo 1 apresentando massas abdominais

Introducción: Los tumores del estroma gastrointestinal (GIST), aunque relativamente raros, representan el 80% de los tumores mesenquimales del tubo digestivo. Se manifiestan en cualquier parte del tubo digestivo y se derivan de las células de Cajal. Pueden presentarse de forma esporádica o asociarse a síndromes familiares como la neurofibromatosis tipo I. El cuadro clínico es variable y con frecuencia su diagnóstico es incidental. El diagnóstico requiere pruebas de imagen asociadas al análisis histopatológico e inmunohistoquímico. La mejor estrategia de tratamiento es la resección quirúrgica y los casos deben analizarse individualmente para verificar ventajas adicionales con la asociación de terapia sistémica. El objetivo de este trabajo es presentar un caso inusual de GIST asociado a neurofibromatosis tipo I en un paciente con diagnóstico incidental tras una semioclusión intestinal secundaria a un episodio de pancreatitis, además de revisar la literatura sobre el tema. Informe del caso: Mujer de 49 años, con antecedente de pancreatitis severa, presentó oclusión intestinal aproximadamente ocho meses después de este episodio. La tomografía computarizada de abdomen reveló una formación heterogénea en la región mesogástrica, que medía 6,6 x 5,1 x 5,3 cm. Se le realizó resección quirúrgica y los estudios histopatológicos e inmunohistoquímicos corroboraron el diagnóstico de GIST. Seis meses después del diagnóstico, la paciente se encuentra en buen estado general y en tratamiento sistémico. Conclusión: Los GIST son tumores raros, pero su diagnóstico debe considerarse en pacientes con neurofibromatosis tipo 1 que presentan masas abdominales

Tumor de GIST, presentación no habitual / GIST tumor: an unusual presentation

RESUMEN El tumor estromal gastrointestinal representa el 3% de las neoplasias gastrointestinales; es el tumor mesenquimático más frecuente. Afecta a hombres mayores de 50 años. El 80% son benignos, la mayoría afectan el estómago e intestino delgado. La incidencia de localización extragastrointestinal es desconocida. Paciente masculino de 56 años, tabaquista, obeso, con hipertensión arterial (HTA) y diabético (DBT), anticoagulado, consulta por dolor en fosa ilíaca derecha, posterior a esfuerzo físico. Se realiza tomografía computarizada (TC) donde se visualiza lesión de aspecto expansivo intraperitoneal que muestra realce periférico. Se decide conducta quirúrgica. Se halla un tumor mesentérico. En su presentación, estos tumores hasta en un 60% suelen ser asintomáticos por lo que resultan solo un hallazgo imagenológico; es indispensable, pues, su sospecha clínica y fundamentalmente el aporte de la inmunohistoquímica para la definición de la patología. El CD 117 es el principal marcador. Su tratamiento de preferencia es siempre quirúrgico, acompañado de tratamientos quimioterápicos.

ABSTRACT Gastrointestinal stromal tumors (GISTs) account for < 3% of gastrointestinal neoplasms and are the most common mesenchymal tumors. They are more common in men > 50 years. They are benign in 80% of the cases and usually occur in the stomach and small intestine. The incidence of extragastrointestinal GISTs is unknown. A 56-year-old male patient sought medical care for abdominal pain in the right iliac fossa that appeared after exercising. The patient was a current smoker, obese, had a history of hypertension (HTN) and diabetes (DBT) and was receiving anticoagulants. A computed tomography (CT) scan showed an expansive mass within the peritoneum with peripheral enhancement. Surgical management was decided. During the procedure, a tumor was found in the mesentery. Up to 60% of these tumors are usually asymptomatic and are incidentally found in imaging tests; therefore, clinical suspicion and, most importantly immunohistochemistry, are essential for the diagnosis. CD117 is the main marker. Surgery is the treatment of choice for GISTs and chemotherapy is also indicated.

GIST gástrico complicado. Una forma de presentación inusual / Complicated gastric GIST. An unusual presentation

RESUMEN Los tumores GIST son un motivo de consulta cada vez más frecuente en las entrevistas de cirugía gastroenterológica. Suelen ser derivados como hallazgos incidentales o por presentar síntomas derivados de su crecimiento. Se presenta el caso clínico de una paciente que requirió internación de urgencia por síndrome anémico agudo. Se comenta su algoritmo diagnóstico y su resolución quirúrgica. Asimismo se comentan los estándares de diagnóstico y tratamiento actuales con especial foco en la estrategia quirúrgica, la cual debe ser individualizada según cada caso.

ABSTRACT Gastrointestinal stromal tumors (GISTs) are becoming an increasingly common reason for consultation in gastroenterology surgery interviews. Patients are usually referred for surgery due to an incidental finding or symptoms associated with tumor growth. We report the case of a female patient who required urgent hospitalization due to acute anemic syndrome. The diagnostic algorithm and surgical approach are described. The current standards of diagnosis and treatment are also discussed, with special focus on the surgical strategy, which must be tailored to each case.

Condroma pulmonar y paraganglioma carotídeo como manifestaciones de la tríada de Carney: reporte de un caso / Pulmonary chondroma and carotid paraganglioma as expressions of Carney's triad: report of a case

Resumen Objetivos: Presentar caso clínico y revisión de la literatura sobre asociación de tumores poco frecuentes compatibles con diagnóstico de tríada de Carney. Paciente y Métodos: Revisión de ficha clínica de paciente de sexo femenino de 39 años de edad con antecedentes de asma, quien acude a servicio de urgencias por síntomas respiratorios. En estudio con imágenes se evidencia masa pulmonar en lóbulo superior derecho probablemente hamartoma y masa en la bifurcación carotídea izquierda compatible con posible paraganglioma. Se completó el estudio con endoscopia digestiva alta sin evidencia de tumor gástrico y PET-CT (tomografía de emisión de positrones-tomografía computarizada) que descartó otras lesiones. Resultados: La paciente fue sometida a resección quirúrgica de ambos tumores (pulmonar y carotídeo). En estudio histopatológico diferido, se plantean los diagnósticos de paraganglioma carotideo y hamartoma pulmonar, el cual, luego de una segunda revisión histopatológica, es corregido a condroma pulmonar. Discusión: La tríada de Carney se compone por la asociación de al menos 2 de 3 tumores: tumor estromal gastrointestinal (GIST), paraganglioma extra-adrenal y condroma pulmonar. Su expresión es variable, coexistiendo en forma completa en solo el 22% de los casos. Conclusión: Los pacientes con sospecha de tríada de Carney deben recibir evaluación multidisciplinaria, estudio completo en búsqueda de tumores asociados y seguimiento a largo plazo por posibles recurrencias o metástasis.

Objective: To present a clinical case and review of the literature on the infrequent association of pulmonary and extra thoracic tumors compatible with Carney's triad. Patient and Methods: Review of clinical records of a 39 years-old female patient with history of asthma who presented in the emergency department with respiratory symptoms. An imaging study showed a pulmonary mass in the right upper lobe with the aspect of hamartoma and a mass in the left carotid artery bifurcation compatible with a possible paraganglioma. Upper gastrointestinal endoscopy showed no evidence of gastric tumor and a PET-CT (Positron Emission Tomography - Computed Tomography) excluded other lesions. Results: Patient underwent surgical resection of both tumors (pulmonary and carotid). Diagnosis of carotid paraganglioma and pulmonary hamartoma were stated by histopathology. However, lung tumor after a second pathological analysis was confirmed to be a pulmonary chondroma. Discussion: Carney's triad is defined by the association of at least 2 of 3 tumors: Gastrointestinal Stromal Tumor (GIST), extraadrenal paraganglioma and pulmonary chondroma. Its expression is variable, coexisting completely in only 22% of cases. Conclusion: Patients with suspected Carney's triad should receive a multidisciplinary assessment, a complete study searching associated tumors and long-term follow-up for recurrences or metastases.

Prognostic factors and management of colorectal gastrointestinal stromal tumors

Introduction: The gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. Even though it can be found in any location of the digestive tract, the colorectal GIST is rare. With this study, we aim to review the current knowledge regarding the prognosis and management of colorectal GIST. Methods: A literature search was conducted in PubMed, and 717 articles were collected. After analyzing these studies, 60 articles were selected to use in this review. Results: The mitotic index, as well as tumor size and location were identified as good discriminators of prognosis in various studies. Surgery remains the only curative therapy for potentially resectable tumors. However, even after surgical resection, some patients develop disease recurrence and metastasis, especially those with highrisk tumors. Therefore, surgical resection alone might be inadequate for the management of all colorectal GISTs. The discovery of GIST's molecular pathway led to a shift in its therapy, insofar as tyrosine kinase inhibitors became part of the treatment schemes for this tumor, revolutionizing the treatment's outcome and prognosis. Discussion/Conclusion: The controversy concerning colorectal GIST prognosis and treatment can be, in part, attributed to the limited number of studies in the literature. In this review, we gathered the most recent knowledge about the prognosis and management of GIST in this rare location and propose two algorithms for its approach. Lastly, we highlight the importance of an individualized approach in the setting of a multidisciplinary team. (AU)

Performance of the Combined Model Based on Both Clinicopathological and CT Texture Features in Predicting Liver Metastasis of High-risk Gastrointestinal Stromal Tumors / 中国医学科学院学报

Objective To investigate the performance of the combined model based on both clinicopathological features and CT texture features in predicting liver metastasis of high-risk gastrointestinal stromal tumors(GISTs). Methods The high-risk GISTs confirmed by pathology from January 2015 to December 2020 were analyzed retrospectively,including 153 cases from the Cancer Hospital of the University of Chinese Academy of Sciences and 51 cases from the Shaoxing Central Hospital.The cases were randomly assigned into a training set(n=142)and a test set(n=62)at a ratio of 7∶3.According to the results of operation or puncture,they were classified into a liver metastasis group(76 cases)and a non-metastasis group(128 cases).ITK-SNAP was employed to delineate the volume of interest of the stromal tumors.Least absolute shrinkage and selection operator(LASSO)was employed to screen out the effective features.Multivariate logistic regression was adopted to construct the models based on clinicopathological features,texture features extracted from CT scans,and the both(combined model),respectively.Receiver operating characteristic(ROC)curve and calibration curve were established to evaluate the predictive performance of the models.The area under the curve(AUC)was compared by Delong test. Results Body mass index(BMI),tumor size,Ki-67,tumor occurrence site,abdominal mass,gastrointestinal bleeding,and CA125 level showed statistical differences between groups(all P<0.05).A total of 107 texture features were extracted from CT images,from which 13 and 7 texture features were selected by LASSO from CT plain scans and CT enhanced scans,respectively.The AUC of the prediction with the training set and the test set respectively was 0.870 and 0.855 for the model based on clinicopathological features,0.918 and 0.836 for the model based on texture features extracted from CT plain scans,0.920 and 0.846 for the model based on texture features extracted from CT enhanced scans,and 0.930 and 0.889 for the combined model based on both clinicopathological features and texture features extracted from CT plain scans.Delong test demonstrated no significant difference in AUC between the models based on the texture features extracted from CT plain scans and CT enhanced scans(P=0.762),whereas the AUC of the combined model was significantly different from that of the clinicopathological feature-based model and texture feature-based model(P=0.001 and P=0.023,respectively). Conclusion Texture features extracted from CT plain scans can predict the liver metastasis of high-risk GISTs,and the model established with clinicopathological features combined with CT texture features has best prediction performance.

Advances in recurrence risk assessment of gastrointestinal stromal tumor / 中华胃肠外科杂志

Identification of prognosis-related risk factors and accurate assessment of risk stratification in patients with gastrointestinal stromal tumor (GIST) is of great significance not only for establishing a reliable prognostic model and developing a follow-up plan but also for selecting potential populations benefiting from neoadjuvant therapies. Although several risk stratification models have been established, it is still challenging to accurately assess patients' risk of recurrence, and the performance of these prediction models still needs to be improved. This review focused on the latest studies in recurrence risk assessment for GIST patients, and summarized potential predictive markers and recurrence risk models related to tumor-related characteristic parameters, novel laboratory examinations, radiological imaging signatures and molecular pathological features, which could provide a reference for accurate risk stratification and individualized targeted therapies for GIST patients.

Prevalence of CKIT and PDGFRA mutation in gastrointestinal stromal tumors among Filipinos

Background@#Gastrointestinal stromal tumors (GIST) is defined as specific, typically kit (CD117)-positive and CKIT or platelet-derived growth factor receptor alpha (PDGFRA) mutation-driven mesenchymal tumors that can occur anywhere in the GI tract. GIST diagnosis relies heavily on immunohistomorphology. However, with the advent of molecular testing, the classification, diagnosis and targeted-therapy for gastrointestinal mesenchymal tumors have been greatly improved. In the Philippines, molecular testing is not yet readily available as in other countries. The local molecular profile of gastrointestinal stromal tumors is a point of investigation as treatment may be more tailored to the patients’ needs.@*Objective@#This study aims to determine the prevalence of CKIT and PDGFRA mutations among formalin-fixed and paraffin embedded gastrointestinal stromal tumors and other gastrointestinal mesenchymal tumors in St. Luke’s Medical Center – Quezon City.@*Methods@#A retrospective cross-sectional study of formalin fixed and paraffin embedded tumor samples diagnosed as Gastrointestinal Stromal Tumor from January 1, 2009 to December 31, 2017 will be analyzed for KIT and PDGFRA mutations. @*Result@#The epidemiology of GIST remains constant in that mean age group is the 5th to 6th decade, with equal gender distribution, and stomach followed by small bowel are the most common sites. Mutational analysis of the GISTs showed predominantly KIT Exon 11 (47.83%) followed by CKIT Exon 9 (13.04%) and PDGFRA Exon 18 (10.87%). For KIT Exon 11, deletion is the most common mutations followed by point mutations. No mutation is detected in 47.83% of GISTs. @*Conclusion@#Mutational analysis for CKIT-PDGFRA is warranted among GIST patients, as it may significantly influence treatment protocol in our patients.

Tumores del estroma gastrointestinal en un Hospital de México / Gastrointestinal stroma tumor in a hospital of Mexico

Introducción: Los tumores del estroma gastrointestinal son neoplasias de comportamiento benigno o maligno. Se originan de las células intersticiales de Cajal del tubo digestivo. Objetivo: Describir dos formas distintas de presentación clínica de los tumores del estroma gastrointestinal. Casos clínicos: El caso 1, paciente femenina de 65 años de edad que acudió por síntomas compresivos del tubo digestivo superior a causa de un gastrointestinal gástrico. El caso 2, paciente masculino de 56 años de edad que acudió por sangrado de tubo digestivo medio ocasionado por un gastrointestinal intestinal. Conclusiones: Los tumores del estroma gastrointestinal tienen distinta presentación clínica. Su tratamiento es esencialmente quirúrgico y en algunos casos complementados con terapia molecular dirigida(AU)

Introduction: Gastrointestinal stromal tumors are neoplasms of benign or malignant behavior. They originate from the interstitial cells of Cajal in the digestive tract. Objective: The objective of this work is to describe two different forms of clinical presentation. Case report: case 1: 65-year-old female patient who presented for compression symptoms of the upper digestive tract due to gastric GIST; case 2: 56-year-old male who presented with bleeding from the middle digestive tract caused by intestinal GIST. Conclusions: GISTs have different clinical presentation. Its treatment is essentially surgical and in some cases supplemented with targeted molecular therapy(AU)

Gist gigante de alto riesgo: Reporte de caso y revisión de la literatura / Giant GIST of High-risk Criteria: Case Report and Literature Review

RESUMEN Los tumores del estroma gastrointestinal (GIST) son las neoplasias mesenquimales más frecuentes del tracto digestivo. Los criterios de estadificación del riesgo, como angioinvasion, tamaño, infiltración y el índice mitótico, permiten realizar un adecuado diagnóstico y tratamiento. Se presenta un paciente masculino de 67 años de edad, quien consultó por he-matemesis y melenas. Endoscópicamente se observó una masa en el estómago de 20x10x6 cm de diámetro de la cual se tomó biopsia para estudio. Al examen histopatológico se diagnósticó un GIST con invasión microscópica de la lámina propia y angioinvasión, estos dos componentes histopatológicos son escasamente tomados en cuenta para clasificar GIST; sin embargo, son muy importantes en este contexto, pues cambian el pronóstico de la enfermedad y con requerimiento de terapia adyuvante con imatinib. El desenlace del paciente fue favorable, debido a la conducta terapéutica establecida. El comportamiento biológico del GIST varía dependiendo de las características clínicas e histopatológicas. Este caso resalta los criterios de alto riesgo del GIST y la necesidad de modificar el tratamiento cuando están presentes.

ABSTRACT Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms of the digestive tract. Risk staging criteria such as angioinvasion, size, infiltration, and mitotic index allow for adequate diagnosis and treatment. A 67-year-old male patient is presented, who consulted for hematemesis and melena. Endoscopically, a 20x10x6 cm diameter mass was observed in the stomach, which was taken for a biopsy for study. On histopathological examination, a GIST with the microscopic invasion of the lamina propia and angioinvasion was diagnosed. These two histopathological components are scarcely taken into account to classify GIST; however, they are very important in this context, changing the prognosis of the disease and requiring adjuvant therapy with imatinib. The outcome of the patient was favorable due to the established therapeutic conduct. The biological behavior of GIST varies depending on the clinical and histopathological characteristics. This case highlights the high-risk criteria for GIST and the need to modify the treatment when present.

Tumor de estroma gastrointestinal extraintestinal gigante: reporte de un caso y revisión de bibliografía / Giant extraintestinal gastrointestinal stromal tumor: Case report and bibliography review

Resumen Los tumores del estroma gastrointestinal (GIST) son tumores infrecuentes del tracto digestivo. Sus localizaciones más frecuentes son el estómago, intestino delgado, colon y recto; su aparición en otros lugares fuera del trato gastrointestinal como el mesenterio, epiplón o retroperitoneo es infrecuente. La tomografía axial computarizada (TAC) y la resonancia magnética (RM) son los estudios de imágenes de primera elección. La recesión quirúrgica es el estándar de oro para los tumores localizados y en los tumores avanzados o metastásicos son tratados con imatinib. A continuación, se presenta el caso de un paciente masculino de 53 años de edad sin antecedentes de patologías previos con cuadro clínico de dolor abdominal generalizado, pérdida de peso de 20 kg aproximadamente, distención abdominal, melena, hematemesis y astenia; en el examen físico presentó abdomen distendido y en la palpación se encontró endurecimiento epigástrico y mesogástrico, y marco colónico izquierdo. En la tomografía de abdomen se observó una masa tumoral de aspecto infiltrativo de aparente origen gástrico, con crecimiento extragástrico e infiltración del bazo, páncreas, raíz mesentérica, epiplón mayor, colon transverso, asas intestinales delgadas e infiltración en el hilio hepático, y metástasis hepática. Además, el cuadro se asoció con enfermedad respiratoria por coronavirus del síndrome respiratorio agudo grave de tipo 2 (SARS-CoV-2; neumonía por coronavirus de 2019 [COVID-19]). Se realizó una biopsia percutánea ecodirigida en el hipocondrio izquierdo y la histología reportó un GIST. En este artículo se revisa la clínica, diagnóstico y tratamiento del GIST gigante extradigestivo.

Abstract Giant extraintestinal gastrointestinal stromal tumors (GIST) are rare tumors of the digestive tract. Its most frequent locations are the stomach, small intestine, colon, and rectum. Its appearance in other places outside the gastrointestinal tract such as the mesentery, omentum, or retroperitoneum is infrequent. Computerized axial tomography (CT) and magnetic resonance imaging (MRI) are the imaging studies of the first choice. Surgical recession is the gold standard for localized tumors and advanced or metastatic tumors are treated with imatinib. This study presents the case of a male patient of 53 years with no history of previous pathologies. The patient was admitted with a clinical condition of generalized abdominal pain, weight loss of approximately 20 kg, abdominal distention, melena, hematemesis, and asthenia. Physical examination revealed a distended abdomen and palpation revealed epigastric and mesogastric hardening and left colonic frame. The abdominal tomography revealed a tumor mass with an infiltrative appearance of apparent gastric origin, with extragastric growth and infiltration of the spleen, pancreas, mesenteric root, greater omentum, transverse colon, thin intestinal loops, and infiltration in the hepatic hilum, and liver metastases. Moreover, the condition was related to the severe acute respiratory syndrome type 2 coronavirus (SARS-CoV-2). An ultrasound-guided percutaneous biopsy was performed in the left upper quadrant and histology reported a GIST. In this article medical condition, diagnosis, and treatment of the Giant extraintestinal gastrointestinal stromal, is reviewed.

Tumor del estroma gastrointestinal / Gastrointestinal stromal tumor

Introducción: El tumor del estroma gastrointestinal, es el tumor mesenquimal más frecuente en el tracto digestivo, que causa sangrado y obstrucción, con una incidencia de 10 a 20 casos por millón de habitantes. La prevalencia es mayor, debido el curso clínico largo de la enfermedad. Objetivo: Presentar un caso inusual de cirugía electiva, con tumor del estroma gastrointestinal digestivo, operado en el servicio de cirugía general. Caso clínico: Paciente masculino de 57 años de edad, que consulta por dolor abdominal en mesogastrio, acompañado de vómitos postprandiales tardíos, pérdida de peso y episodios recurrentes de sangrado digestivo bicolor, se ingresa de forma electiva y se estudia. Se interviene quirúrgicamente con el diagnóstico presuntivo de tumor abdominal. Se encuentra durante la laparotomía tumor de 14 por 20 centímetros que compromete la luz del intestino delgado, se decide realizar extracción del tumor y anastomosis término terminal convencional. El paciente fue egresado a los ocho días con evolución favorable y pendiente de resultado anatomopatológico, el cual informó tumor del estroma gastrointestinal. Conclusiones: Los tumores del estroma gastrointestinal son poco frecuentes como causa de cirugía electiva en los servicios de cirugía general(AU)

Introduction: Gastrointestinal stromal tumor is the most frequent mesenchymal tumor in the digestive tract, causing bleeding and obstruction, with an incidence of 10 to 20 cases per million inhabitants. The prevalence is higher, due to the long clinical course of the disease. Objective: To present an unusual case of elective surgery, with a gastrointestinal digestive stromal tumor, operated on in the general surgery service. Clinical case: A 57-year-old male patient who consulted for abdominal pain in the mesogastrium, accompanied by late postprandial vomiting, weight loss and recurrent episodes of bicolor digestive bleeding, was admitted electively and studied. Surgery was performed with the presumptive diagnosis of abdominal tumor. During the laparotomy, a 14 by 20-centimeter tumor that compromises the lumen of the small intestine is found; it is decided to perform extraction of the tumor and a conventional end-to-end anastomosis. The patient was discharged after eight days with a favorable evolution and pending histopathological result, which reported a gastrointestinal stromal tumor. Conclusions: Gastrointestinal stromal tumors are rare as a cause of elective surgery in general surgery services(AU)

Tumores estromales gastrointestinales (GIST) gástricos, serie de casos / Gastrointestinal stromal tumors (GIST). Case series

Resumen Introducción: Los tumores estromales gastrointestinales (GIST) representan hasta el 2 % de las neoplasias gastrointestinales, estos aparecen en cualquier parte del tracto gastrointestinal y son encontrados más frecuentemente en el estómago (60 %). El diagnóstico se realiza por la expresión de un receptor de factor de crecimiento de tirosina-cinasa, antígeno de diferenciación (CD) 117, lo que lo diferencia de los otros tumores mesenquimales como leiomiomas, leiomiosarcomas, leiomioblastomas y tumores neurogénicos, que no expresan esta proteína. Objetivo: El objetivo de nuestro trabajo es caracterizar los GIST de localización gástrica con respecto a su presentación clínica, diagnóstico, manejo, recurrencia y supervivencia. Métodos: Se trata de un estudio observacional, retrospectivo basado en una serie de casos. Se realizó una extracción de la información por medio de la revisión de las historias clínicas de los pacientes con GIST gástricos en un centro oncológico de Bogotá entre enero de 2005 y diciembre de 2015. La información recolectada incluyó tipo de manejo y abordaje quirúrgico, localización, tamaño, índice mitótico y clasificación de riesgo. Resultados: Se encontraron 31 pacientes con diagnóstico de GIST gástrico. La edad media fue de 62,3 años, con una mediana de 61 años. De los 31 pacientes, 18 fueron mujeres y 13 hombres. El tiempo de seguimiento estuvo entre un mínimo de 2,4 meses y un máximo de 214 meses, La mediana de seguimiento fue de 36 meses. Conclusiones: Los GIST son tumores potencialmente malignos, y el de localización gástrica es el más frecuente. El diagnóstico y tratamiento dependen de su tamaño y localización dentro del estómago. El manejo es variado y consiste en la resección quirúrgica, en la que los procedimientos son mínimamente invasivos, en combinación con la endoscopia, que son una buena alternativa al tratamiento abierto hasta que haya necesidad de terapia sistémica.

Abstract Introduction: Gastrointestinal stromal tumors (GIST) account for up to 2% of gastrointestinal neoplasms. They may appear anywhere in the gastrointestinal tract and are most frequently found in the stomach (60%). The diagnosis is made based on the expression of the tyrosine-protein kinase KIT CD117, which differentiates it from other mesenchymal tumors such as leiomyomas, leiomyosarcomas, leiomyoblastomas, and neurogenic tumors, that do not express this protein. Objective: To characterize the clinical presentation, diagnosis, treatment, recurrence, and survival of GISTs in the stomach. Materials and methods: This is an observational retrospective study based on a case series. Data was collected after reviewing the medical records of patients diagnosed with GIST at a cancer center in Bogotá between January 2005 and December 2015. The data included type of treatment and surgical approach, location, size, mitotic index, and risk classification. Results: There were 31 patients diagnosed with GIST. Their mean age was 62.3 years, with a median of 61 years. Of the 31 patients, 18 were women and 13 were men. Follow-up time ranged from a minimum of 2.4 months to a maximum of 214 months. The median follow-up time was 36 months. Conclusions: GISTs are potentially malignant tumors, with gastric location being the most frequent. Diagnosis and treatment depend on their size and location in the stomach. Treatment options vary, ranging from surgical resection, where minimally invasive procedures along with endoscopy are a suitable alternative to open surgery, to the need for systemic therapy.