Context: Immunohistochemistry (IHC) to differentiate germ cell tumors. Aims: The aim of the study is to differentiate seminomatous and nonseminomatous germ cell tumors (GCTs) with morphological overlap using a minimal and affordable panel of IHC markers. Settings and Design: This is a retrospective observational study. Subjects and Methods: All testicular GCTs (TGCT) which were diagnosed on biopsies and/or resection specimens (prechemotherapy) between January 2014 and June 2019. The demographic, clinical, and imaging findings were noted from the medical records. Hematoxylin and eosin (H and E)-stained sections were reviewed for morphology. The IHC markers constituted Octamer-binding transcription factor (OCT) 3/4, glypican 3 (GPC3), CD117, CD30, placental-like alkaline phosphatase, Sal-like protein 4, and β-human chorionic gonadotropin (HCG). IHC markers were performed in various combinations depending on the morphology, and a panel constituting OCT 3/4, CD117, GPC3, and CD30 was performed on cases with diagnostic dilemma and morphological overlaps. Statistical Analysis Used: Sensitivity, specificity, positive (PPV), and negative predictive value (NPV) were calculated for suggested panel of IHC OCT 3/4, CD117, GPC3, and CD30. Results: The study included 36 patients with TGCT with a mean age of 27 (15–58) years. Nonseminomatous tumors were the most common (86%). The concise panel was performed in 20/36 (56%) tumors to resolve the diagnosis. The sensitivity, specificity, PPV, and NPV for OCT3/4 were 80%, 55%, 31%, and 92% in seminomas and 65%, 100%, 100%, and 46% in embryonal carcinomas (EC), for CD117 was 89%, 82%, 73%, and 93% in seminomas and 60%, 77%, 60%, and 77% in yolk sac tumors (YST), for GPC3 was 95%, 90%, 95%, and 90% in YST, CD30 96%, 100%, 100%, and 91% in ECs, respectively. Conclusions: Designing a novel concise and affordable IHC panel constituting OCT 3/4, CD117, GPC3, and CD30 has good sensitivity and specificity in differentiating seminomas, YST, and EC, respectively. Additional markers, namely β-HCG, can be used in identifying the choriocarcinoma component.

Background: Breast sarcomas are extremely rare, can be primary or secondary, pose a high risk of recurrence with an overall poor prognosis. Primary breast sarcomas constitute < 1% of all primary breast malignancies and less than 5% of all sarcomas. Sarcomas arising in phyllodes tumors account for < 6 % of all phyllodes tumors. The most common subtype of both primary and secondary sarcoma is angiosarcoma. Methods: This was a retrospective study of patients diagnosed as sarcoma of breast (excluding malignant phyllodes and metaplastic carcinoma) during the period from January 2016 to July 2019. The demographic and clinical features were noted from the medical records. The details of gross specimens (grossed in strict accordance with CAP protocols) were noted. The haematoxylin and eosin-stained slides along with immunohistochemistry (IHC) (pan cytokeratin, calponin, vimentin, SMA, CD117, Ki 67, desmin, CD10, CK5/6, EMA, p63, CD34, CD56, myogenin, CD99, p16, S100, BCL2, CD31, caldesmon and CD68) were reviewed and categorized according to WHO (2019) criteria. Result: The median age of patients was fifty years. There were fourteen breast sarcomas including one arising in phyllodes tumor during the study period. These included undifferentiated pleomorphic sarcoma (4), liposarcoma (2), myxofibrosarcoma (2), angiosarcoma (2), one each of leiomyosarcoma, rhabdomyosarcoma, fibrosarcoma and stromal sarcoma. Despite using a wide panel of IHC markers, 4/14 (28.57%) sarcomas were classified as undifferentiated pleomorphic sarcoma. Conclusion: Primary breast sarcomas are rare tumors and pose diagnostic challenge. It is important to categorize these entities in view of the differing biologic behavior and molecular profiles. Morphology along with IHC is important for diagnosis, treatment and prognosis.