Emergent approach to small bowel tumors: diagnosis and treatment.

BACKGROUND: This study presents the diagnosis and treatment of rare small bowel tumors through clinical cases. METHODS: Patients treated between 2000 and 2023 were included in the study. The clinical records of the patients were analyzed retrospectively. RESULTS: A total of 34 patients were included in the study. Of these patients, 26 (75.5%) were male and eight (23.5%) were female. The mean age of the patients was 62.1 years. The most common symptoms and signs were abdominal pain (76.4%), bloating (38.2%), and nausea and vomiting (17.6%). Diagnostic methods included computed tomography (CT) (82.3%), upper gastrointestinal double balloon enteroscopy (35.2%), and capsule endoscopy (5.8%). Diagnoses included adenocarcinoma in 13 cases, gastrointestinal stromal tumors (GISTs) in 12 cases, and neuroendocrine tumors (NETs) in two cases. CONCLUSION: Small bowel tumors frequently present with abdominal pain, bloating, and nausea and vomiting. CT and endoscopic procedures are the primary diagnostic tools. Small bowel cancers are often diagnosed late due to subtle clinical findings and the limitations of endoscopic imaging. Targeted screening strategies may be beneficial for certain at-risk and symptomatic patient groups. Early surgical intervention offers significant advantages for diagnosed patients.

Fulminant ectopic Cushing's syndrome caused by metastatic small intestine neuroendocrine tumour - a case report and review of the literature.

Cushing's syndrome (CS) secondary to adrenocorticotropic hormone (ACTH) producing tumours is a severe condition with a challenging diagnosis. Ectopic ACTH-secretion often involves neuroendocrine tumours (NET) in the respiratory tract. ACTH-secreting small intestine neuro-endocrine tumours (siNET) are extremely rare entities barely reported in literature. This review is illustrated by the case of a 75-year old woman with fulminant ectopic CS caused by a ACTH-secreting metastatic siNET. Severe hypokalemia, fluid retention and refractory hypertension were the presenting symptoms. Basal and dynamic laboratory studies were diagnostic for ACTH-dependent CS. Extensive imaging studies of the pituitary and thorax-abdomen areas were normal, while [68Ga]Ga-DOTATATE PET-CT revealed increased small intestine uptake in the left iliac fossa. The hypercortisolism was well controlled with somatostatin analogues, after which a debulking resection of the tumour was performed. Pathological investigation confirmed a well-differentiated NET with sporadic ACTH immunostaining and post-operative treatment with somatostatin analogues was continued with favourable disease control.

Clinicopathological features and prognosis of primary small bowel adenocarcinoma: a large multicenter analysis of the JSCCR database in Japan.

BACKGROUND: The clinicopathological features and prognosis of primary small bowel adenocarcinoma (PSBA), excluding duodenal cancer, remain undetermined due to its rarity in Japan. METHODS: We analyzed 354 patients with 358 PSBAs, between January 2008 and December 2017, at 44 institutions affiliated with the Japanese Society for Cancer of the Colon and Rectum. RESULTS: The median age was 67 years (218 males, 61.6%). The average tumor size was 49.9 (7-100) mm. PSBA sites consisted of jejunum (66.2%) and ileum (30.4%). A total of 219 patients (61.9%) underwent diagnostic small bowel endoscopy, including single-balloon endoscopy, double-balloon endoscopy, and capsule endoscopy before treatment. Nineteen patients (5.4%) had Lynch syndrome, and 272 patients (76.8%) had symptoms at the initial diagnosis. The rates for stages 0, I, II, III, and IV were 5.4%, 2.5%, 27.1%, 26.0%, and 35.6%, respectively. The 5-year overall survival rates at each stage were 92.3%, 60.0%, 75.9%, 61.4%, and 25.5%, respectively, and the 5-year disease-specific survival (DSS) rates were 100%, 75.0%, 84.1%, 59.3%, and 25.6%, respectively. Patients with the PSBA located in the jejunum, with symptoms at the initial diagnosis or advanced clinical stage had a worse prognosis. However, multivariate analysis using Cox-hazard model revealed that clinical stage was the only significant predictor of DSS for patients with PSBA. CONCLUSIONS: Of the patients with PSBA, 76.8% had symptoms at the initial diagnosis, which were often detected at an advanced stage. Detection during the early stages of PSBA is important to ensure a good prognosis.

Epidemiology of gastroenteropancreatic neuroendocrine neoplasms: a review and protocol presentation for bridging tumor registry data with the Italian association for neuroendocrine tumors (Itanet) national database.

Neuroendocrine neoplasms (NENs) are rare tumors with diverse clinical behaviors. Large databases like the Surveillance, Epidemiology, and End Results (SEER) program and national NEN registries have provided significant epidemiological knowledge, but they have limitations given the recent advancements in NEN diagnostics and treatments. For instance, newer imaging techniques and therapies have revolutionized NEN management, rendering older data less representative. Additionally, crucial parameters, like the Ki67 index, are missing from many databases. Acknowledging these gaps, the Italian Association for Neuroendocrine Tumors (Itanet) initiated a national multicenter prospective database in 2019, aiming to gather data on newly-diagnosed gastroenteropancreatic neuroendocrine (GEP) NENs. This observational study, coordinated by Itanet, includes patients from 37 Italian centers. The database, which is rigorously maintained and updated, focuses on diverse parameters including age, diagnostic techniques, tumor stage, treatments, and survival metrics. As of October 2023, data from 1,600 patients have been recorded, with an anticipation of reaching 3600 by the end of 2025. This study aims at understanding the epidemiology, clinical attributes, and treatment strategies for GEP-NENs in Italy, and to introduce the Itanet database project. Once comprehensive follow-up data will be acquired, the goal will be to discern predictors of treatment outcomes and disease prognosis. The Itanet database will offer an unparalleled, updated perspective on GEP-NENs, addressing the limitations of older databases and aiding in optimizing patient care. STUDY REGISTRATION: This protocol was registered in clinicaltriasl.gov (NCT04282083).

A systematic review and meta-analysis of magnetic resonance and computed tomography enterography in the diagnosis of small intestinal tumors.

Objective: To explore the potential value of magnetic resonance (MR) and computed tomography (CT) enterography in the diagnosis of small intestinal tumor (SIT). Methods: Articles reporting on the diagnosis of SIT by MR and CT enterography deposited in Chinese and foreign literature databases were identified and evaluated using the quality assessment of diagnostic accuracy studies (QUADAS). The diagnostic data extracted from the articles were adopted for meta-analysis using Meta-disc 1.40 software. Analysis was undertaken to compare the sensitivity, specificity, positive and negative likelihood ratios, and the diagnostic odds ratio (DOR) of MR and CT enterography in the diagnosis of SIT. The diagnostic values of the two imaging methods were analyzed by summary receiver operating characteristic (SROC) curves. The meta-analysis was registered at INPLASY (202380053). Results: A total of eight articles, including 551 cases of SIT were included in this analysis. The pooled sensitivity and specificity of MR enterography were 0.92 (95% CI [0.89-0.95]) and 0.81 (95% CI [0.74-0.86]), respectively, whilst CT enterography had a sensitivity of 0.93 (95% CI [0.90-0.95]) and a specificity of 0.83 (95% CI [0.76-0.88]). For MR enterography, the combined positive likelihood ratio was 4.90 (95% CI [3.50-6.70]), the combined negative likelihood ratio was 0.10 (95% CI [0.07-0.14]), and the area under the receiver operating characteristic curve (AUROC) was 0.940. For CT enterography, the corresponding values were 5.40 (95% CI [3.90-7.40]), 0.08 (95% CI [0.06-0.12]), and 0.950, respectively. When the pretest probability for MR was assumed to be 50%, the posterior probabilities for positive and negative results were calculated as 83% and 9%, respectively. For CT enterography with a pretest probability of 50%, the posterior probabilities of positive and negative results were 84% and 8%, respectively. Conclusion: MR and CT enterography have high accuracy in the diagnosis of SIT and have a valuable role in the diagnosis and management of these tumors.

Small Intestinal Adenocarcinoma Arising at the Anastomotic Site after Kasai Operation for Biliary Atresia: A Case Report and Literature Review.

Biliary atresia is an obliterative cholangiopathy of unknown etiology. Hepatic portoenterostomy, in which obliterated extrahepatic bile ducts are resected and bile flow is restored, known as Kasai operation, is performed within 3 months after birth. While this operation enhances long-term survival of patients, the occurrence of primary malignant hepatic tumors has been increasing. We report a case of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation. A 49-year-old man, who underwent Kasai operation for biliary atresia when he was 2 months old, experienced rapidly progressive jaundice and liver dysfunction. Deceased-donor liver transplantation was performed for liver failure. Macroscopically, there was a white-yellow tumor located at the anastomotic site of hepatic portoenterostomy of the resected liver. Pathological examination revealed a well-differentiated adenocarcinoma with some Paneth cells in the neoplastic lesion. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) but positive for cytokeratin 20 (CK20) and a homeobox domain-containing transcription factor (CDX2). Mucin expression in tumor cells was negative for mucin 1 (MUC1) and mucin 6 (MUC6) and positive for mucin 2 (MUC2) and mucin 5AC (MUC5AC). The pathological diagnosis was small intestinal adenocarcinoma originating from the jejunum. The patient was discharged 48 days after the operation. The patient had not experienced recurrence at 10 months after the operation. This is the first report of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation for biliary atresia. Special care should be taken for the patients after Kasai operation with acute progressive jaundice and liver dysfunction because there is a possibility of malignancy in their native liver.

SEOM-GETNE clinical guidelines for the diagnosis and treatment of gastroenteropancreatic and bronchial neuroendocrine neoplasms (NENs) (2022)

'Neuroendocrine neoplasms (NENs) are a heterogeneous family of tumors of challenging diagnosis and clinical management. Their incidence and prevalence continue to rise mainly due to an improvement on diagnostic techniques and awareness. Earlier detection, along with steadfast improvements in therapy, has led to better prognosis over time for advanced gastrointestinal and pancreatic neuroendocrine tumors. The aim of this guideline is to update evidence-based recommendations for the diagnosis and treatment of gastroenteropancreatic and lung NENs. Diagnostic procedures, histological classification, and therapeutic options, including surgery, liver-directed therapy, peptide receptor radionuclide therapy, and systemic hormonal, cytotoxic or targeted therapy, are reviewed and discussed, and treatment algorithms to guide therapeutic decisions are provided (AU)

Updates in histopathological classification and tissue biomarkers of digestive neuroendocrine neoplasms: What the clinician should know.

Histopathological classifications of neuroendocrine neoplasms (NEN) change regularly and the latest WHO classification published in 2022, which concerns all NEN in the body, attempts to standardize classifications in the different locations. Differentiation and proliferation mainly assessed by Ki-67 index are still the cornerstone of those classifications. However, many markers are now used for diagnostic (to check neuroendocrine differentiation, to identify the site of origin of a metastasis, to help separating high-grade neuroendocrine tumors/NET and neuroendocrine carcinoma/NEC), prognostic or theranostic purposes. NENs are often heterogeneous and this can lead to difficulties in classifications, biomarker and prognostic assessment. These different points are discussed successively in this review, insisting especially on the frequent digestive, gastro-entero-pancreatic (GEP) localizations.

Neoplasia neuroendócrina aderida em mesentério e intestino grosso: relato de caso / Adhered neuroendocrine neoplasm in the mesentery and large intestine - case report / Neoplasia neuroendocrina adherida en mesenterio e intestino grueso: reporte de caso

Introdução: O tumor neuroendócrino pancreático gastrointestinal foi descoberto em 1907 por Siegfried Oberdorfer, que mais tarde, em 1929, descreveu seu potencial maligno, relativamente raro. Os tumores neuroendócrinos gastrointestinais e do ducto pancreaticobiliar são tumores heterogêneos com diferentes comportamentos biológicos e clínicos, dependendo da origem do tumor primário, tipos de células neuroendócrinas e características patológicas. Podem aparecer na maioria dos órgãos, ter diferentes etiologias e diferentes características clínicas, morfológicas e genômicas. Objetivo: Relatar o caso de um paciente com neoplasia neuroendócrina aderida em mesentério e intestino grosso. Material e Método: Estudo tipo relato de caso. Resultados: Paciente do sexo masculino, 80 anos, com lesão neoplásica neuroendócrina em mesentério e íleo terminal grau 1, não funcionante. Hipótese diagnóstica: suboclusão intestinal por massa tumoral de aproximadamente 4 cm. Tratamento cirúrgico realizado em 2020, guiado por exame histológico demonstrando a presença de neoplasia neuroendórina midgut pT3pN1M0 em íleo terminal (margem circunferencial, IPN1, IAL1, AVS0, micrometástase para 1 LN em 4 avaliados), IHQ: tumor neuroendócrino pancreático gastrointestinal grau 1 (ki67: 1%), não funcionante e sem evidências de doença a distância. Paciente apresentou uma boa evolução pós cirúrgica, entretanto com insuficiência renal aguda, a qual teve melhora posteriormente. Durante o acompanhamento ambulatorial, paciente apresentou perda ponderal considerável, sugestiva de recidiva. Conclusão: Condição relativamente rara, o tumor NNE pode ser inicialmente assintomático ou acompanhado por dores abdominais em cólica, assim, devem ser buscados diagnósticos diferenciais para dor abdominal. Laparotomia exploradora, cirurgia de remoção da massa e análise histológica com estadiamento para definir o tratamento oncológico de escolha fazem parte da conduta médica

Introduction: The gastrointestinal neuroendocrine pancreatic tumor was discovered in 1907 by Siegfried Oberdorfer, who later, in 1929, described its malignant potential, relatively rare. Gastrointestinal and pancreaticobiliary neuroendocrine tumors are heterogeneous tumors with different biological and clinical behaviors, depending on the origin of the primary tumor, types of neuroendocrine cells and pathological characteristics. They may appear in most organs, have different etiologies and different clinical, morphological and genomic characteristics. Objective: To report the case of a patient with neuroendocrine neoplasia adhered to the mesentery and large intestine. Material and Method: Study type case report. Results: Male patient, 80 years old, with neuroendocrine neoplastic lesion in mesentery and grade 1 terminal ileum, not functioning. Diagnostic hypothesis: intestinal subocclusion by tumor mass of approximately 4cm. Surgical treatment performed in 2020, guided by histological examination demonstrating the presence of neuroendocrine midgut neoplasm pT3pN1M0 in terminal ileum (circumferential margin, IPN1, IAL1, AVS0, micrometastasis for 1 LN in 4 evaluated), IHC: gastrointestinal neuroendocrine pancreatic tumor grade 1 (ki67: 1%) no evidence of distant disease. The patient presented a good post-surgical evolution, however with acute renal failure, which improved later. During outpatient follow-up, the patient presented considerable weight loss, suggestive of recurrence. Conclusion: Relatively rare condition, the NNE tumor may be initially asymptomatic or accompanied by abdominal pain in colic, thus, differential diagnoses for abdominal pain should be sought. Exploratory laparotomy, mass removal surgery and histological analysis with staging to define the oncological treatment of choice are part of the medical approach

Introducción: El tumor neuroendocrino pancreático gastrointestinal fue descubierto en 1907 por Siegfried Oberdorfer, quien posteriormente, en 1929, describió su potencial maligno, relativamente raro. Los tumores neuroendocrinos del conducto gastrointestinal y pancreatobiliar son tumores heterogéneos con diferentes comportamientos biológicos y clínicos, dependiendo del origen del tumor primario, tipos de células neuroendocrinas y características patológicas. Pueden aparecer en la mayoría de los órganos, tener diferentes etiologías y distintas características clínicas, morfológicas y genómicas. Objetivo: Reportar el caso de un paciente con neoplasia neuroendocrina adherida al mesenterio e intestino grueso. Material y Método: Estudio tipo reporte de caso. Resultados: Paciente masculino de 80 años con lesión neoplásica neuroendocrina no funcionante en mesenterio e íleon terminal. Hipótesis diagnóstica: suboclusión intestinal por masa tumoral de aproximadamente 4 cm. Tratamiento quirúrgico realizado en 2020, guiado por examen histológico demostrando la presencia de neoplasia neuroendocrina de intestino medio pT3pN1M0 en íleon terminal (margen circunferencial, IPN1, IAL1, AVS0, micrometástasis a 1 LN en 4 evaluados), IHC: tumor neuroendocrino pancreático gastrointestinal grado 1 (ki67: 1 %), no funcionante y sin evidencia de enfermedad a distancia. El paciente tuvo una buena evolución postoperatoria, sin embargo con insuficiencia renal aguda, que mejoró posteriormente. Durante el seguimiento ambulatorio, la paciente presentó una importante pérdida de peso, sugestiva de recidiva. Conclusión: Condición relativamente rara, el tumor NNE puede inicialmente ser asintomático o acompañarse de dolor abdominal tipo cólico, por lo que se deben buscar diagnósticos diferenciales para el dolor abdominal. La laparotomía exploradora, la cirugía para extirpar la masa y el análisis histológico con estadificación para definir el tratamiento oncológico de elección son parte del manejo medico

Small bowel neuroendocrine tumours - casting the net wide.

PURPOSE OF REVIEW: Our aim is to provide an overview of small bowel neuroendocrine tumours (NETs), clinical presentation, diagnosis algorithm and management options. We also highlight the latest evidence on management and suggest areas for future research. RECENT FINDINGS: Dodecanetetraacetic acid (DOTATATE) scan can detect NETs with an improved sensitivity than when compared with an Octreotide scan. It is complimentary to small bowel endoscopy that provides mucosal views and allows the delineation of small lesions undetectable on imaging. Surgical resection is the best management modality even in metastatic disease. Prognosis can be improved with the administration of somatostatin analogues and Evarolimus as second-line therapies. SUMMARY: NETs are heterogenous tumours affecting most commonly the distal small bowel as single or multiple lesions. Their secretary behaviour can lead to symptoms, most commonly diarrhoea and weight loss. Metastases to the liver are associated with carcinoid syndrome.

Gastrointestinal Stromal Tumors: Diagnosis, Follow-up and Role of Radiomics in a Single Center Experience.

Gastrointestinal stromal tumors (GISTs) arise from the interstitial cells of Cajal in the gastrointestinal tract and are the most common intestinal tumors. Usually GISTs are asymptomatic, especially small tumors that may not cause any symptoms and may be found accidentally on abdominal CT scans. Discovering of inhibitor of receptor tyrosine kinases has changed the outcome of patients with high-risk GISTs. This paper will focus on the role of imaging in diagnosis, characterization and follow-up. We shall also report our local experience in radiomics evaluation of GISTs.

[Clinicopathological characteristics and prognosis of patients with small bowel tumors: A single center analysis of 220 cases].

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.

Gastrointestinal stromal tumors of the small intestine: the challenge of diagnosis and the outcome of management.

PURPOSES: Gastrointestinal stromal tumor (GIST) is a rare small intestinal tumor. Most patients usually report long-period complaints due to difficult diagnoses. A high grade of suspicion is required for early diagnosis and initiation of the proper management. METHODS: A retrospective study of all patients with small intestinal GIST who were operated in the period between January 2008 and May 2021 at Mansoura University Gastrointestinal Surgical Center (GIST). RESULTS: Thirty-four patients were included in the study with a mean age of 58.15 years (± 12.65) with a male to female ratio of 1.3:1. The mean duration between onset of symptoms and diagnosis was 4.62 years (± 2.34). Diagnosis of a small intestinal lesion was accomplished through abdominal computed tomography (CT) in 19 patients (55.9%). The mean size of the tumor was 8.76 cm (± 7.76) ranging from 1.5 to 35 cm. The lesion was of ileal origin in 20 cases (58.8%) and jejunal in 14 cases (41.2%). During the scheduled follow-up period, tumor recurrence occurred in one patient (2.9%). No mortality was encountered. CONCLUSION: Diagnosis of a small bowel GISTs requires a high grade of suspicion. Implementing new diagnostic techniques like angiography, capsule endoscopy, and enteroscopy should be encouraged when suspecting these lesions. Surgical resection is always associated with an excellent postoperative recovery profile and very low recurrence rates.

Biomarkers in gastroenteropancreatic neuroendocrine neoplasms.

PURPOSE OF REVIEW: Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) represent a heterogenous group of rare tumors emanating from neuroendocrine cells that are clinically silent for prolonged periods of time without detection. Traditional biomarkers lack sufficiently high enough specificity and sensitivity for these tumors and their secreted products. New molecules are sought to improve accuracy of detection and monitoring of GEP-NENs. The purpose of this review is to highlight recent advances in the discovery of novel biomarkers and their potential characteristics and utility as markers of GEP-NENs. RECENT FINDINGS: Several recent GEP-NEN investigations regarding NETest demonstrate superior sensitivity and specificity in diagnosis and disease monitoring as compared with chromogranin A. Among several tissue-based emergent candidate molecules as biomarkers for GEP-NEN INSM1 has demonstrated consistently excellent characteristics when compared with traditional markers including chromogranin A, synaptophysin, and CD56. SUMMARY: For the diagnosis and clinical monitoring of NEN, there still exists a considerable need for better biomarkers. Novel technology has resulted in a promising liquid biopsy for the detection and monitoring of GEP-NENs. The search for improved tissue biomarkers has resulted in identification of one potential candidate whereas several others remain in the investigatory phase.

Progress in the Treatment of Small Intestine Cancer.

OPINION STATEMENT: Small intestine cancer is rare, accounting for approximately 3% of all gastrointestinal malignancies. The most common histological subtypes include adenocarcinoma, neuroendocrine tumours (NETs) and gastrointestinal stromal tumours (GISTs). In localised disease, surgery remains the mainstay of treatment and the best approach to improve survival. Current treatment for small intestine adenocarcinoma (SIA) is extrapolated from small studies and data from colorectal cancer (CRC). There is limited evidence to guide therapy in the adjuvant setting. However, there are small phase II studies in the advanced setting providing evidence for the role of chemotherapy and immunotherapy. There is also limited evidence assessing the efficacy of targeted therapies. Small intestine NETs are rare, with evidence for somatostatin analogue therapy, particularly in the low to intermediate-grade well-differentiated tumours. Poorly differentiated NETs are generally managed with chemotherapy but have worse outcomes compared with well-differentiated NETs. The management of small intestine GISTs is largely targeting KIT mutations with imatinib. Recent trials have provided evidence for effective therapies in imatinib-resistant tumours and the potential role of immunotherapy. The aim of this article was to review the evidence for the current management and recent advances in the management of small intestine adenocarcinoma, NETs and GISTs.

[Gastroenteropancreatic neuroendocrine tumors : (GEP-NENs)]. / Neuroendokrine Neoplasien des Gastrointestinaltrakts : (GEP-NENs).

The entity of NENs represent a highly heterogenous group of malignancies that require a multidisciplinary approach during the treatment of patients. The following article aims to provide a concise overview of the current state of the art in diagnostics and therapy. One specific feature of G1/G2 NENs is that the indication for surgery is given even in metastatic settings. Specific details regarding the treatment of its various different subgroups need to be gathered from available guidelines or current clinical studies. The field of nuclear medicine offers promising options for diagnostics and therapy which needs further investigation.

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.

[Chinese expert consensus on gastroenteropancreatic neuroendocrine neoplasms (2022 edition)].

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are highly heterogeneous tumors. According to the 2019 World Health Organization classification and grading criteria for neuroendocrine neoplasms of the gastrointestinal tract and hepatopancreatobiliary organs, GEP-NENs include well-differentiated neuroendocrine tumors (NETs), poorly differentiated neuroendocrine carcinomas (NECs), and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs). GEP-NETs may present as hormonally functioning or nonfunctioning tumors and may have distinct clinical features based on their sites of origin. The Expert Committee of Neuroendocrine Tumors, Chinese Society of Clinical Oncology revised and updated the 2016 version of Chinese expert consensus on GEP-NENs. The update the consensus includes the epidemiology, clinical manifestations, biochemical and imaging examinations, pathological features, and treatment and follow-up of GEP-NENs.