Diagnostic utility of CD117, CD133, SALL4, OCT4, TCL1 and glypican-3 in malignant germ cell tumors of the ovary

Aim: Primary ovarian malignant germ cell tumors (OMGCTs) are rare and difficult to diagnose. Immunohistochemistry can help in the diagnosis and development of new management strategies. The aim of this study was to investigate the frequency of CD117, CD133, SALL4, OCT4, TCL1 and glypican-3 marker expression in OMGCTs. Material and Methods: We examined the expression of six markers in 87 (85 pure and two mixed OMGCTs) cases of OMGCT using immunohistochemical staining. Staining was graded in a semiquantitative manner as follows: negative (no staining), 1+ (1-30% staining), 2+ (31-60% staining), or 3+ (>60% staining). Results: All 27 dysgerminomas and all 31 YSTs showed CD117 expression, with only nine (29%) positively stained in immature teratomas. SALL4 and glypican-3 were strongly positive in 100 and 79.3%, respectively, of YSTs. All dysgerminomas were positive for OCT4, whereas all YSTs and immature teratomas were negative. 100% of dysgerminomas were positive for TCL1, but all immature teratomas were negative. CD133 expression showed generally the same tendency in the 3 OMGCTs. Conclusion: CD117 can be used as a diagnostic marker for dysgerminoma and YST. SALL4 is a more sensitive and specific marker for YSTs than glypican-3. SALL4 and OCT4 are useful in distinguishing YST from dysgerminoma.