[TFE3-rearranged perivascular epithelioid cell tumors: a clinicopathological analysis of eight cases].

Objective: To investigate the clinicopathological, immunohistochemical and molecular genetic characteristics of TFE3-rearranged perivascular epithelioid cell tumor (PEComa). Methods: Eight cases of PEComa with TFE3 rearrangement diagnosed in the First Affiliated Hospital of Air Force Medical University from January 2014 to July 2022 were collected. Three were consultation cases and 5 were collected from our hospital; 7 cases were resection specimens and 1 case was a needle biopsy specimen. Routine histolopathological analysis, immunohistochemical staining, fluorescence in situ hybridization (FISH) and the next-generation sequencing were performed. Clinical data were collected and the prognosis was assessed. Results: The 8 patients consisted of 5 females and 3 males with a median age of 45 years (ranged from 25 to 65 years). The tumor location included 1 uterus, 1 liver, 1 urachus, 2 kidneys, 1 abdominal cavity, 1 colon, and 1 retroperitoneum (3 subsequent recurrences in the abdominal cavity, pelvis and ovary, and abdominal cavity, respectively). Morphologically, the tumor cells were uniform and epithelioid with translucent or eosinophilic cytoplasm. They were arranged in nests or sheets, most of which were separated by thin-walled blood vessels. There were no papillary structures, and no overt smooth muscle or fat components. Atypical features were seen in 3 cases, with bizarre nuclei and tumor giant cells. Large areas of necrosis were visible, and mitosis was common (up to 28/50 HPF). Melanin deposition was present in 3 cases. Immunohistochemical staining showed diffuse and strong positivity for TFE3 in 8/8 cases and for HMB45 in 6/8 cases; focal positivity for Cathepsin K and Melan-A in 6/8 cases and for SMA in 2/8 of cases. All cases were negative for CKpan, PAX8 and Desmin. TFE3 gene break-apart was detected by FISH in all 8 cases, 4 of which underwent next-generation sequencing, and it revealed that 2 cases presented with SFPQ::TFE3 fusion, 1 case with ASPSCR1::TFE3 fusion, and 1 case with no chimeric fusion. Seven cases were followed up for 4-94 months. All cases were alive; 4 cases were disease-free, 2 cases showed recurrence, and 1 case had metastasis at initial diagnosis. Conclusions: TFE3-rearranged PEComa has unique histomorphological, immunohistochemical and molecular characteristics. The biological behavior is aggressive, which could lead to recurrence and metastasis, and warrants close clinical follow-up.

A CARE-compliant article: A case report of retroperitoneal endometrial stromal sarcoma with multiple pulmonary metastases and literature review.

RATIONALE: Endometrial stromal sarcoma is an extremely rare mesenchymal neoplasm occurring in the extrauterine. Retroperitoneal endometrial stromal sarcoma with multiple pulmonary metastases, in particular, is extremely rare. PATIENT CONCERNS: Forty-seven-year-old woman (gravida 3, para 2), was referred to our institution with complaints of fever. DIAGNOSES: Ultrasound and computed tomographic imaging of the abdomen identified the presence of masses in the pelvic region. Additionally, computed tomographic scans and X-ray evaluations of the thorax detected dispersed masses in both the lungs and pelvic area. Histopathological analysis of the pelvic region indicated the presence of low-grade endometrial stromal sarcoma. A computed tomography-guided pneumocentesis was conducted to further characterize the pulmonary lesions, confirming the diagnosis of low-grade endometrial stromal sarcoma. INTERVENTIONS: The patient underwent tumor resection, subsequent treatment with Medroxyprogesterone acetate for 6 months, received microwave ablation for multiple lung metastases, PARP1 inhibitor for 4 courses, and has been undergoing chemotherapy (epirubicin/ifosfamide) up to the present time. OUTCOMES: Partial remission was obtained after the above treatment and this patient is now still alive maintaining for 3 years. LESSONS: The identification and management of this disease remain a significant challenge due to its low prevalence. Further research involving a larger number of cases is necessary to ensure consistency in diagnosis and to establish effective treatment guidelines.

Laparoscopic removal of retroperitoneal schwannoma in renal hilum: a case report.

BACKGROUND: Schwannomas in the renal hilum are rare among retroperitoneal tumors. However, the possibility of malignant findings cannot be ruled out, and surgery is often indicated. This case was expected to be difficult to remove laparoscopically because the tumor was sandwiched between the arteriovenous veins of the renal portal. Sometimes, the tumor should be resected with a conservative approach to the kidney to preserve the renal function. CASE PRESENTATION: Our patient was a 51-year-old Asian-Japanese man who was referred to our department for a retroperitoneal tumor in the renal hilum. Since malignancy could not be ruled out due to its size (45 × 48 × 55 mm) on imaging, the tumor was excised laparoscopically. Histopathology revealed schwannoma. CONCLUSIONS: We herein report a case in which a renal hilar tumor between renal arteriovenous vessels was successfully resected laparoscopically.

Image features and clinical analysis of retroperitoneal pelvic schwannoma: a case report.

BACKGROUND: Schwannomas are benign usually encapsulated nerve sheath tumors derived from the Schwann cells, and affecting single or multiple nerves. The tumors commonly arise from the cranial nerves as acoustic neurinomas but they are extremely rare in the pelvis and the retroperitoneal area. Retroperitoneal pelvic schwannomas often present with non-specific symptoms leading to misdiagnosis and prolonged morbidity. CASE PRESENTATION: We report the case of a 59-year-old woman presenting with a feeling of heaviness in the lower abdomen who was found to have a retroperitoneal pelvic schwannoma originating from the right femoral nerve. She had a history of two resections of peripheral schwannomas at four different sites of limbs. After conducting magnetic resonance imaging, this pelvic schwannoma was misdiagnosed as a gynecological malignancy. The tumor was successfully removed by laparoscopic surgery. Pathological analysis of the mass revealed a benign schwannoma of the femoral nerve sheath with demonstrating strong, diffuse positivity for S-100 protein. CONCLUSIONS: Although retroperitoneal pelvic schwannoma is rare, it should be considered in the differential diagnosis of pelvic masses, especially in patients with a history of neurogenic mass or the presence of neurogenic mass elsewhere.

Extraskeletal osteosarcoma infiltrating pancreas, spleen, gastric, and left kidney: a case report.

BACKGROUND: Extraskeletal osteosarcoma is an extremely rare malignancy that accounts for 1% of soft tissue sarcoma and 4.3% of all osteosarcoma. Extraskeletal osteosarcoma can develop in a patient between the ages of 48 and 60 years. The incidence of extraskeletal osteosarcoma is slightly higher in male patients than in females. CASE PRESENTATION: A 50-year-old Caucasian male patient presented with a 6-month history of intermittent lower-left back pain that limits his activity. Prior ultrasonography and abdominal computed tomography scan showed a diagnosis of kidney stone and tumor in the lower-left abdomen. The computed tomography urography with contrast revealed a mass suspected as a left retroperitoneal malignant tumor. Hence, the tumor was resected through laparotomy and the patient continued with histopathological and immunohistochemistry examination with the result of extraskeletal osteosarcoma. CONCLUSION: Extraskeletal osteosarcoma presents diagnostic challenges requiring multimodal examination, including histological and immunohistochemistry analyses. This case underscores the aggressive nature and poor prognosis despite undergoing the current suggested treatment.

Survival and prognostic factors of primary retroperitoneal sarcomas after surgery: a single-center experience.

PURPOSE: The percentage of retroperitoneal sarcomas (RPS) among all soft tissue sarcomas ranges from 10 to 15%. Surgery remains the gold standard for RPS. In this study, we analyzed the impact of surgical treatment for primary RPS on recurrence and overall mortality at a Chinese institution and identified and evaluated prognostic variables. METHODS: Data from patients with RPS who underwent surgical treatment were retrospectively analyzed. The patients were treated at a single center from January 2000 to June 2018. Retrospectively collected demographic, clinicopathological, and surgical factors were examined. Overall survival (OS) and disease-free survival (DSF) were used as the primary endpoints. Predicted 5-year survival rates, encompassing both DFS and OS, were derived from the Sarculator prognostic nomogram. RESULTS: A total of 110 patients met the inclusion criteria. The median follow-up time after surgery for patients with primary RPS was 5.3 years. During this period, 59 patients died. The 5-year OS and DFS estimates were 63.5% and 35.3%, respectively. In a multivariate analysis, poor OS following surgical treatment of primary RPS was independently correlated with FNCLCC grade (p < 0.001) and surgical margin status (p = 0.016). FNCLCC grade (p = 0.001) and surgical margin status (p = 0.002) were also independently associated with poor DFS. The C-indices for 5-year OS and DFS survival utilizing the Sarculator prognostic nomogram were 0.71 and 0.73 respectively. CONCLUSION: The overall mortality rate of patients with RPS was considered acceptable. OS and DFS prognostic markers were established for primary RPS. Tumor grade and intraregional margins are other factors that affect survival and recurrence.

Discordance of retroperitoneal and thoracic histologic findings in patients with metastatic germ cell tumors at postchemotherapy residual tumor resection.

INTRODUCTION AND OBJECTIVES: Postchemotherapy residual tumor resection (PC-RTR) is an important part of the multimodal treatment for patients with metastatic germ cell tumors. Simultaneous retroperitoneal and thoracic metastases often require consecutive surgical procedures. This study analyzes the histologic findings after abdominal and thoracic surgery in order to tailor the sequence and intensity of surgery. PATIENTS AND METHODS: From a total of 671 PC-RTRs from 2008 to 2021 we analyzed 50 patients with stage III non-seminomatous germ cell tumor (NSGCT) who had undergone both retroperitoneal and thoracic postchemotherapy residual tumor resection after first-line and salvage chemotherapy. RESULTS: All patients included had stage III NSGCT. 39 and 11 patients received first-line and salvage chemotherapy, respectively. 45 (90%) patients received retroperitoneal resection first, followed by thoracic surgery. Three patients (6%) underwent thoracic surgery before retroperitoneal surgery and two patients (4%) underwent simultaneous surgery. Overall, the histology of retroperitoneal and thoracic specimens was discordant in 23% of cases. After first-line chemotherapy, of fourteen patients with necrosis in retroperitoneal histology, four patients had vital carcinoma in lung histology. In patients with teratoma in the retroperitoneum, the thoracic findings were concordant in most cases (78%). When teratomatous elements were also present in the orchiectomy specimen, concordance was 100%. After salvage chemotherapy, the discordance rate was 55%. CONCLUSION: The data presented in this study underline that retroperitoneal residual masses with necrosis cannot reliably predict histologic findings of thoracic specimens. Patients with teratoma in the retroperitoneum have a high likelihood of teratoma in the thoracic specimen.

Optimizing surgical strategies for retroperitoneal liposarcoma: a comprehensive evaluation of standardized aggressive surgical policies.

BACKGROUND: Retroperitoneal liposarcoma (RLPS) constitutes the majority of retroperitoneal sarcomas. While surgical resection remains the sole curative approach, determining the optimal surgical strategy for RLPS remains elusive. This study addresses the ongoing debate surrounding the optimal surgical strategy for RLPS. METHODS: We recruited 77 patients with RLPS who underwent aggressive surgical policies. Patients were categorized into three surgical subtypes: suprapancreatic RLPS, pancreatic RLPS, and subpancreatic RLPS. Our standardized surgical strategy involved resecting macroscopically uninvolved adjacent organs according to surgical subtypes. We collected clinical, pathological and prognostic data for analyses. RESULTS: The median follow-up was 45.5 months. Overall survival (OS) and recurrence-free survival (RFS) were significantly correlated with multifocal RLPS, pathological subtype, recurrent RLPS and histological grade (P for OS = 0.011, 0.004, 0.010, and < 0.001, P for RFS = 0.004, 0.001, < 0.001, and < 0.001, respectively). The 5-Year Estimate OS of well-differentiated liposarcoma (WDLPS), G1 RLPS, de novo RLPS and unifocal RLPS were 100%, 89.4%, 75.3% and 69.1%, respectively. The distant metastasis rate was 1.4%. The morbidity rates (≥ grade III) for suprapancreatic, pancreatic, and subpancreatic RLPS were 26.7%, 15.6%, and 13.3%, respectively. The perioperative mortality rate is 2.6%. CONCLUSIONS: Standardized aggressive surgical policies demonstrated prognostic benefits for RLPS, particularly for G1 RLPS, WDLPS, unifocal RLPS, and de novo RLPS. This approach effectively balanced considerations of adequate exposure, surgical safety, and thorough removal of all fat tissue. G1 RLPS, WDLPS, unifocal RLPS, and de novo RLPS could be potential indications for aggressive surgical policies.

Surgical outcomes of major vascular resection for retroperitoneal liposarcoma from a high­volume sarcoma center: a propensity score matching analysis.

PURPOSE: Radical resection of retroperitoneal liposarcoma (RLPS) may necessitate vascular resection and reconstruction. The study was conducted to assess surgical outcomes of surgery for RLPS with major vascular involvement. METHODS: Patients with RLPS who underwent surgical resection at the Sarcoma Center of Peking University Cancer Hospital between April 2011 and December 2022 were identified from a prospectively maintained database. Patients were classified into two groups: vascular resection and non-vascular resection groups. A propensity score matching analysis was performed to eliminate baseline differences between the groups. Surgical details and postoperative outcomes were analyzed. Furthermore, prognostic factors for local recurrence-free survival (LRFS) and overall survival (OS) were assessed. RESULTS: Overall, 199 patients were identified and the median follow-up period was 48 (interquartile range [IQR] 45-69) months. Vascular resection was performed in 42 (21%) patients, 25 of whom had vascular infiltration. A total of 39 patients had vascular replacement and 3 patients underwent partial resection (side-wall resection). Vascular resection was burdened by higher rates of major morbidity (38% vs. 14%, p < 0.001) and 30-day mortality (7.1% vs. 1.3%, p = 0.005). After propensity-matched analysis, patients who underwent vascular resection had 5-year LRFS and OS rates comparable to those without vascular involvement. Major vascular resection was not an independent risk factor for LRFS or OS. CONCLUSIONS: Although accompanied by increased risks of major morbidity and mortality, the major vascular resection enabled radical resection in patients with advanced RLPS, affording comparable 5-year LRFS and OS rates compared to those who did not.

Computed tomography angiography features of a retroperitoneal extra-adrenal paraganglioma in a cat.

A 7-year-old spayed female domestic shorthair cat was presented for evaluation of a large-volume abdominal space-occupying lesion. A computed tomography angiography examination detected a round retroperitoneal mass, in contact with the large abdominal vessels, characterized by an external hyperattenuating capsule and a larger hypoattenuating center. The capsule was soft-tissue attenuating with marked heterogenous contrast enhancement. The center was hypoattenuating pre- and post-contrast administration. The mass displaced both kidneys laterally and the descendent colon ventrally. The mesenteric veins and both phrenicoabdominal veins were markedly increased in diameter. However, the adrenals were not involved. On the excretory phase, no contrast enhancement was observed in either ureter, except for the proximal tract of the right ureter. At laparotomy, both ureters entered the mass that was adherent to the great abdominal vessels. The cytological diagnosis was retroperitoneal extra-adrenal paraganglioma. In cats, retroperitoneal extra-adrenal paragangliomas are very rare. This is the first computed tomography angiography report of a retroperitoneal extra-adrenal paraganglioma in a domestic cat. Key clinical message: This report describes the computed tomography angiography features of a rare case of a retroperitoneal extra-adrenal paraganglioma in a cat. These features could be taken into consideration to direct the diagnosis of a possible neuroendocrine origin for a retroperitoneal mass in a cat.

Caractéristiques de l'angiographie par tomodensitométrie d'un para-gangliome extra-surrénalien rétropéritonéal chez un chatUne chatte domestique à poils courts, âgée de 7 ans, stérilisée, a été présentée pour évaluation d'une lésion abdominale de grand volume occupant de l'espace. Un examen d'angiographie tomodensitométrique a détecté une masse rétropéritonéale ronde, en contact avec les gros vaisseaux abdominaux, caractérisée par une capsule externe hyper-atténuante et un centre hypo-atténuant plus large. La capsule présentait une atténuation des tissus mous avec une prise de contraste hétérogène marquée. Le centre était hypoatténuant avant et après l'administration le milieu de contraste. La masse a déplacé latéralement les deux reins et ventralement le côlon descendant. Le diamètre des veines mésentériques et des deux veines phrénico-abdominales était nettement augmenté. Cependant, les surrénales n'étaient pas impliquées. À la phase excrétrice, aucune augmentation de contraste n'a été observée dans les deux uretères, à l'exception du tractus proximal de l'uretère droit. Lors de la laparotomie, les deux uretères pénétraient dans la masse adhérente aux gros vaisseaux abdominaux. Le diagnostic cytologique était un paragangliome extra-surrénalien rétropéritonéal. Chez le chat, les para-gangliomes extra-surrénaliens rétropéritonéaux sont très rares. Il s'agit du premier rapport d'angiographie par tomodensitométrie d'un para-gangliome extra-surrénalien rétropéritonéal chez un chat domestique.Message clinique clé:Ce rapport décrit les caractéristiques de l'angiographie par tomodensitométrie d'un cas rare de paragangliome extra-surrénalien rétropéritonéal chez un chat. Ces caractéristiques pourraient être prises en considération pour orienter le diagnostic d'une éventuelle origine neuroendocrinienne d'une masse rétropéritonéale chez un chat.(Traduit par Dr Serge Messier).

Cadaveric analysis of surgical techniques and working space for retroperitoneal tumors as model for improving resection of neuroblastoma.

PURPOSE: Neuroblastoma, the most common extracranial solid tumor in children under 5 years, often surrounds visceral arteries. This study aimed to analyze the working space provided by standardized surgical techniques at key arterial landmarks in adult cadavers. METHODS: We assessed in eight adult cadavers the mobilization of the left colon, spleen and pancreas, right colon, duodenum and mesenteric root, access to the bursa omentalis. The average working space score (AWSS) was evaluated at the left and right renal artery, left and right side of the coeliac trunk, superior mesenteric and common hepatic artery. The score was defined as: (0) vessel not visible, (1) working space at the vessel ≤ 1x diameter of the aorta, (2) < 3x the diameter of the aorta, (3) ≥ 3x diameter of the aorta. RESULTS: The maximum AWSS of 3 was achieved at key vascular landmarks through specific mobilization techniques. CONCLUSION: Additional mobilization of spleen, pancreas and mesenteric root and access to the bursa omentalis increase surgical working space at major visceral arteries. The results of our investigation provide surgeons with a useful guide to prepare for abdominal neuroblastoma resection.

[Retroperitoneal schwannoma mimicking colorectal cancer metastases: a false positive result report.] / Schwannoma retroperitoneal simulando metástasis de cáncer colorrectal: reporte de un resultado falso positivo.

Introduction: schwannomas are benign and common soft tissue tumors. They are usually asymptomatic and are discovered for other reasons. Materials: we present the case of an 82-year-old male patient with a recent diagnosis of moderately differentiated adenocarcinoma of the colon and a hypermetabolic periaortic nodule as an incidental finding. Results: percutaneous biopsy of the periaortic nodule confirmed the diagnosis of schwannoma. At one year of follow-up, growth of the schwannoma has been demonstrated. There are no signs of progression of his oncological disease. Conclusions: schwannomas are benign tumors, rarely found in the retroperitoneum and can be sources of false-positive positron emission tomography results.

Introducción: los schwannomas son tumores benignos y frecuentes de las partes blandas. Habitualmente son asintomáticos y son descubiertos por otros motivos. Materiales y métodos: presentamos el caso de un paciente masculino de 82 años con diagnóstico reciente de adenocarcinoma de colon moderadamente diferenciado y con un nódulo periaórtico hipermetabólico como hallazgo incidental. Resultados: la biopsia percutánea del nódulo periaórtico confirmó el diagnóstico de schwannoma. Al año de seguimiento, se ha demostrado crecimiento del schwannoma. No hay signos de progresión de su enfermedad oncológica. Conclusión: los schwannomas son tumores benignos, infrecuentes en el retroperitoneo y pueden ser fuentes de resultados falsos positivos en tomografía por emisión de positrones.

Real-world experience of Doxorubicin Monotherapy for Advanced or Metastatic Retroperitoneal Sarcoma: A Single Institutional Study of 16 Cases.

BACKGROUND/AIM: Anthracycline-based chemotherapies including doxorubicin monotherapy are recommended in major guidelines for patients with advanced or metastatic retroperitoneal sarcoma (RPS); however, few studies have reported the outcomes of doxorubicin monotherapy for these patients. We herein investigated the oncological efficacy and safety of doxorubicin monotherapy for patients with advanced or metastatic RPS in real-world clinical practice. PATIENTS AND METHODS: Sixteen patients diagnosed with advanced or metastatic retroperitoneal sarcoma, receiving doxorubicin monotherapy as first-line treatment between February 2017 and March 2023 at our Institution were analyzed. Response rate, progression-free survival (PFS) periods, overall survival (OS) period, and adverse event (AE) profiles were retrospectively investigated. RESULTS: The median age of patients was 69.5 years. Best responses to doxorubicin were as follows: complete response, 0 patients (0.0%); partial response, 3 (18.8%); stable disease, 9 (56.3%); and progressive disease, 4 (25.0%). The objective response rate and disease control rate were 18.8 and 75.0%, respectively. During the observation period (median, 22 months, range=2-53 months), median PFS and OS periods were 8.0 and 24.0 months, respectively. The following AEs Grade ≥3 occurred: neutropenia in 14 patients (87.5%), febrile neutropenia in 5 (31.3%), leukopenia in 2 (12.5%), thrombocytopenia in 1 (6.3%), and heart failure in 1 (6.3%). Grade ≥3 nausea and vomiting did not occur and there was no treatment-related death. CONCLUSION: The oncological outcomes of doxorubicin monotherapy for RPS in real-world clinical practice were not inferior to those of the EORTC trial. The incidence of hematological AEs was higher; however, severe gastrointestinal AEs were prevented by prophylactic antiemetics and there were no treatment-related deaths. Collectively, doxorubicin monotherapy with appropriate prophylactic agents is a valid option for patients with advanced or metastatic RPS.

Mesna, Doxorubicin, Ifosfamide and Dacarbazine (MAID) Combination Chemotherapy for Retroperitoneal Sarcoma: A Single-center Experience.

BACKGROUND/AIM: There is limited evidence regarding the systemic treatment of retroperitoneal soft-tissue sarcoma, and the current Japanese guidelines fail to make definitive suggestions. Here, we report our experience with combination chemotherapy of mesna, doxorubicin, ifosfamide, and dacarbazine (MAID) in this population. PATIENTS AND METHODS: We retrospectively reviewed the records of eight patients (three male and five female) who received MAID for pathologically diagnosed metastatic unresectable retroperitoneal sarcoma (either leiomyosarcoma or pleomorphic sarcoma) between October 2019 and January 2022. Treatment efficacy, tolerability (need for dose reduction), and safety profiles were evaluated and summarized. RESULTS: At initiation, the median age was 56.0 years, and the body mass index was 20.0 kg/cm2 Six patients had Eastern Cooperative Oncology Group performance status scores of 0. The net clinical benefit was a partial response in three (37.5%) patients, stable disease in four (50.0%), and progressive disease in one (12.5%). During the median 90.8 weeks of follow-up, disease in five patients progressed, resulting in a median progression-free survival of 48.4 weeks, and five deaths occurred, resulting in an overall survival of 95.1 weeks. Commonly observed adverse events were neutropenia (eight patients), anemia (eight patients), and decreased platelet count (seven patients), which led to dose reduction (60-80%) in six patients. CONCLUSION: MAID combination therapy may be an acceptable option for advanced retroperitoneal sarcoma; however, its benefits must be carefully assessed owing to its not insignificant toxicity.

Retroperitoneal dermoid cyst complicated with uterine adenomyoma: a case report and literature review.

Pelvic masses frequently originate from the pelvic cavity and are often associated with uterine, ovarian, or intestinal disorders. This report describes the case of a patient with a pelvic mass diagnosed as a retroperitoneal dermoid cyst at our hospital. We analyzed this case and conducted a literature review, to mitigate the risk of misdiagnosis and enhance the treatment of retroperitoneal masses.

Prognostic value of tumour-related factors associated with canine retroperitoneal hemangiosarcoma in comparison with other anatomic presentations: A retrospective observational study.

BACKGROUND: Dogs with retroperitoneal hemangiosarcoma (HSA) exhibit variable postoperative median survival times (MST). OBJECTIVE: To retrospectively evaluate the prognostic value of selected tumour-related factors, such as tumour size, rupture, invasion into adjacent tissue, involvement of lymph node and distant metastasis, they were analysed in dogs with retroperitoneal HSA. METHODS: Ten dogs with retroperitoneal HSA managed solely with surgical excision were reviewed and compared with spleen (71) and liver (9) HSA. The Kaplan-Meier method and log-rank analysis were used compare MSTs between factors. Multivariable Cox proportional-hazard analysis was used to compare differences between arising sites. RESULTS: Retroperitoneal HSA showed comparatively longer postoperative MST compared with that of spleen and liver HSA and demonstrated significantly longer MST (p = 0.003) for tumours ≥5 cm (195 days) than <5 cm (70 days). Spleen HSA revealed significantly shorter MSTs in involvement of distant lymph nodes (23 days) and distant metastasis (39 days) than those in negative (83 days, p = 0.002 and 110 days, p < 0.001, respectively). Liver HSA also revealed significantly shorter MST (16.5 days compared with 98 days, p = 0.003) for distant metastasis. Additionally, hazard ratios (HRs) and their forest plot for overall HSA revealed as poor prognostic factors, arising sites (spleen; HR 2.78, p = 0.016 and liver; HR 3.62, p = 0.019), involvement of distant lymph nodes (HR 2.43, p = 0.014), and distant metastasis (HR 2.86, p < 0.001), and as better prognostic factor of tumour size ≥5 cm (HR 0.53, p = 0.037). CONCLUSION: In combination with overall HSA, retroperitoneal HSA shows comparatively longer postoperative MST compared to spleen and liver HSA, associated with tumour size ≥5 cm suggesting better prognostic factor.

Analysis of clinical and pathological characteristics of retroperitoneal paraganglioma and associated prognostic factors.

BACKGROUND AND OBJECTIVES: The aim of this study is to explore the long-term prognostic risk factors associated with patients diagnosed with retroperitoneal paraganglioma (RPGL) and examine their clinical and pathological characteristics. METHODS: Expressions of biomarkers were identified using immunohistochemistry (IHC) and case databases were retrospectively searched. Survival analysis was performed using Kaplan-Meier and Cox risk regression to identify the factors that influence the postoperative progression-free survival of patients with RPGL. RESULTS: A total of 105 patients, most of whom had tumors situated in the paraaortic region, and whose average tumor size was 8.6 cm, were enrolled in this study. The average follow-up duration was 51 months, with a mortality rate of 19% and a recurrence and metastasis rate of 41.9%. Tumors were assessed using the modified Grading system for Adrenal Pheochromocytoma and Paraganglioma (GAPP), and SDHB, S-100, and Ki-67 were stained using IHC in all cases. Out of the total cases examined, negative in SDHB expression were observed in 18.1% of cases, S-100 expression was negative in 36.2% of cases, and endovascular tumor enboluswas present in approximately 25.7% of cases. The results of the univariate analysis indicated that several factors significantly influenced the progression-free survival of patients with PGL as follow: maximum tumor diameter (>5.5 cm), tumor morphological features, tumor grading (modified GAPP score > 6), SDHB negative, S-100 negative, and expression of proliferation index Ki-67 (>3%) (X2 = 4.217-27.420, p < 0.05). The results of the multivariate analysis indicated that negative of S-100 (p = 0.021) and SDHB (p = 0.038), as well as intravascular tumor thrombus (p = 0.047) expression were independent risk factors for progression-free survival in patients. CONCLUSION: RPGL is characterized by diverse biological features and an elevated susceptibility to both recurrence and metastasis. Both SDHB and S-100 can be employed as traditional IHC indicators to predict the metastatic risk of PGL, whereas the tumor histomorphology-endovascular tumor enbolus assists in determining the metastasis risk of RPGL.

The association between CD34 expression status and the clinicopathological behavior of dedifferentiated liposarcoma.

Lipogenic and fibrous tumors are thought to originate from CD34-positive stromal fibroblastic/fibrocystic cells. Well-differentiated lipogenic tumors typically express CD34, whereas dedifferentiated liposarcoma (DDLPS) often loses it. We conducted survival analyses involving 59 patients with DDLPS. Males comprised 53% of the cohort, and the median age at the time of wide resection of primary DDLPS was 60 years. Loss of CD34 expression was defined as when ≥50% of the dedifferentiated area was immunohistochemically negative for CD34. As a result, 39 of the 59 patients showed loss of CD34 expression during the initial operation for DDLPS. In the univariate analyses, the tumor site in the retroperitoneum/abdominal cavity and loss of CD34 expression were significantly associated with poor overall survival. In the multivariate analyses, loss of CD34 expression (HR = 2.26; 95% CI = 1.02-5.02; p = 0.04) and the tumor site in the retroperitoneum/abdominal cavity (HR = 3.11; 95% CI = 1.09-8.86; p = 0.03) were retained as independent prognostic factors. Six CD34-positive cases lost CD34 expression when they developed metastasis and/or local recurrence, suggesting that the loss was associated with the later stage of the tumor. Therefore, an association existed between the loss of CD34 expression and clinicopathological behaviors such as poorer prognoses and recurrence.