Solitary fibrous tumor of head and neck region; A clinicopathological study of 67 cases emphasizing the diversity of histological features and utility of various risk stratification models.

BACKGROUND: Head and neck SFT (HNSFT) exhibit diverse histological features and can mimic various neoplasms with different treatment and behavior. While risk stratification systems have been developed for this tumor at various anatomic sites, a specific scheme for head and neck tumors is lacking. Our aim was to describe the histologic patterns present in HNSFT cases as well as assess the utility of risk assessment models in this location. METHODS: A retrospective review of pathology reports and microscopy glass slides of HNSFT cases diagnosed between January 2010 and August 2022 was performed.STAT6 was additionally performed on selected cases if needed. Follow up was obtained and various risk stratification models were applied. RESULTS: Sixty seven cases of HNSFT were collected (age range from 11 to 87 years; median 42 years; M:F 1.6:1). Most common tumor sites were orbit (n = 21; 31.3 %), sinonasal tract (n = 18; 26.9 %), and oral cavity (n = 13; 19.4 %). Tumor size ranged from 1 to 16 cm (median 4cm). Apart from common histological features, tumor cells also showed focal epithelioid morphology, clear cell change and nuclear atypia in a subset of cases. Stromal findings included myxoid and lipomatous change, pseudoglandular spaces, pseudovascular spaces and multinucleated stromal giant cells. CD34 and STAT6 were expressed in 57/67 (85.1 %) and 56/56 (100 %) cases, respectively. Recurrence was observed in 4/26 (15.4 %) cases, while none (0/22) of the patients experienced distant metastasis (follow up 1-150 months; median 20.5 months). Clinical outcome was partially concordant with risk-categories of different risk stratification models. CONCLUSION: Knowledge about histological diversity of HNSFT is essential for establishing correct diagnosis. Current risk stratification models do not perfectly predict outcome, and larger studies are needed to develop more accurate criteria for aggressive behavior.

Prognostic factors, oncological treatment and outcomes of uterine sarcoma: 10 years' clinical experience from a tertiary care center in Pakistan.

BACKGROUND: Uterine sarcoma is an uncommon aggressive malignancy. Optimal management and prognostic factors have yet to be well recognized due to their rarity and various histological subtypes. This study aims to investigate these patients' prognostic factors, treatment modalities, and oncological outcomes. METHODS: A single-center retrospective cohort study was conducted on all patients diagnosed with uterine sarcoma and treated from January 2010 to December 2019 in a tertiary-care hospital in Pakistan. The data were analyzed using STATA software and stratified on the histological subtype. Survival rates were estimated using the Kaplan-Meier method. Crude and adjusted hazard ratios with 95% CI were estimated using univariate and multivariate analysis. RESULTS: Of the 40 patients, 16(40%) had uterine leiomyosarcoma (u-LMS), 10(25%) had high-grade endometrial stromal sarcoma (HGESS), 8(20%) had low-grade endometrial stromal sarcoma (LGESS) and 6(15%) had other histological subtypes. The median age of all patients was 49 (40-55.5). Thirty-seven (92.5%) patients underwent primary surgical resection, and 24 (60%) patients received adjuvant systemic chemotherapy. The survival plots showed the overall population's DFS of 64 months and the OS of 88 months (p-value = 0.001). The median DFS in all patients was 12 months, and the median OS was 14 months (p-value = 0.001). A small but significant DFS benefit was found in patients who received adjuvant systemic chemotherapy, 13.5 versus 11 months (p-value = 0.001). Multivariate Cox-regression analysis revealed that large tumor size and advanced FIGO stage were substantial factors associated with decreased survival. CONCLUSION: Uterine sarcomas are rare malignancies with poor prognosis. Multiple factors, including tumor size, mitotic count, stage of the disease, and myometrial invasion, impact survival outcomes. Adjuvant treatment may decrease the recurrence rate and improve DFS but do not affect OS.

Hepatic epithelioid hemangioendothelioma: case series of a rare vascular tumor mimicking metastases.

BACKGROUND: Hepatic epithelioid hemangioendothelioma is an extremely rare malignant vascular tumor which is often multifocal and, in many cases, discovered incidentally. Here, we describe the clinicopathological features of hepatic epithelioid hemangioendothelioma cases seen in our practice and present a detailed review of the published literature. METHODS: All cases of hepatic epithelioid hemangioendothelioma diagnosed in Department of Pathology and Laboratory Medicine, Aga Khan University Hospital between January 1, 2006 and December 31, 2019 were included in the study. Slides were reviewed and follow up was obtained. RESULTS: Seven cases were reported during the study period. There were 4 females and 3 males. Age range was 20 to 77 years, mean age was 45 years. Three patients presented with right upper abdominal pain; 1 patient presented with jaundice while 3 patients were asymptomatic. In all 7 cases, lesions were identified on imaging studies. In 5 cases, liver lesions were multifocal. Clinical differential diagnosis in all cases was metastatic carcinoma and multifocal hepatocellular carcinoma. Liver function tests were normal in 5 cases. In 1 patient, tumor had already metastasized to the right lung. On histological examination of liver core biopsies performed in all 7 cases, classic histological features of epithelioid hemangioendothelioma were seen. Tumor cells expressed positivity for vascular markers (CD 34, CD31 and ERG) and were negative for cytokeratins, Hep par 1 and Glypican 3. Surgical resection was not performed in any of the 7 cases and all patients were treated by chemotherapy. Follow up was available in 5 cases. Of these, 3 patients died of disease and another patient was alive with metastases in both lungs, omentum and colon. CONCLUSION: Clinicopathological features of the 7 cases in our series and detailed review of published literature is presented. Prognosis was bad in our cases most likely due to fact that surgical resection could not be performed in any of the cases owing to lack of surgical expertise for liver tumor surgery in most parts of the country.