Human WT1 blocking peptide

Tubo-ovarian transitional cell carcinoma (TCC) is grouped with high-grade serous carcinoma (HGSC) in the current World Health Organization classification. TCC is associated with BRCA mutations and a better prognosis compared with HGSC. Previous papers examining the immunohistochemical features of TCC have studied limited numbers of samples. No marker reflecting the biological difference between TCC and HGSC is known. We collected a large cohort of TCC to determine whether TCC and HGSC could be distinguished by immunohistochemistry. A tissue microarray was built from 89 TCC and a control cohort of 232 conventional HGSC. Immunohistochemistry was performed, scored, and statistically analyzed for routine markers of HGSC and urothelial tumors: PAX8, WT1, p53, p16, ER, p63, and GATA3. Using scoring cutoffs commonly employed in clinical practice, the immunohistochemical profile of TCC was indistinguishable from HGSC for all markers. However, more detailed scoring criteria revealed statistically significant differences between the 2 groups of tumors with respect to ER, PAX8, and WT1. HGSC showed more diffuse and intense staining for PAX8 (P=0.004 and 0.001, respectively) and WT1 (P=0.002 and 0.002, respectively); conversely, TCC showed more intense staining for ER (P=0.007). TCC and HGSC therefore show subtle differences in their immunohistochemical profiles which might reflect underlying (epi)genetic differences. Further studies using proteomic analysis will focus on the identification of differentially expressed proteins that might serve as markers of TCC-like differentiation, which could help explain biologic differences between TCC and HGSC and might identify other cases of HGSC with a better prognosis.

Objectives. Desmoplastic small round cell tumor (DSRCT) is an aggressive round cell sarcoma that arises in the abdominal cavity/pelvis of young males. We sought to expand its clinicopathologic spectrum. Methods. Cases of DSRCT presenting in patients >30 years of age or tumors arising outside of the abdominal cavity/pelvis were retrieved. Results. Thirty-four cases were identified. Sixteen tumors arose at atypical sites (head/neck, intracranial, thigh, axilla/shoulder, inguinal/paratesticular, intraosseous, and uterine corpus). The remaining 18 patients were older than 30 years, and their tumors involved the abdomen or pelvis. The majority of cases showed areas with classic histology, while 6 cases exhibited solid growth and 5 showed macronodular architecture. Cytologic appearance included round cell, rhabdoid, epithelioid, and small cell. Conclusion. DSRCT may arise at nonabdominal locations in both pediatric and adult populations, as well as intra-abdominally in older adults, and these tumors exhibit high rates of metastasis and morbidity.