KLK4 was highly expressed in all of the SER ovarian carcinoma cell lines (eight of eight), SER epithelial carcinomas (11 of 11), and two adenomas, whereas it was expressed at a lower level (or not at all) in normal ovaries (four of six), mucinous epithelial tumors (three of four), endometrioid carcinomas (four of five), clear cell carcinomas (two of three), or granulosa cell tumors (three of six).
Estrogen receptor alpha and PR were frequently expressed in adult granulosa cell tumors (66% and 98%, respectively) and Sertoli-Leydig cell tumors (79% and 86%, respectively).
FOXL2 immunostaining was present in 95 of 119 (80%) SCSTs, including >95% of aGCTs, juvenile granulosa cell tumors, fibromas, and sclerosing stromal tumors.
FOXL2 mutation analysis is a useful adjunct in distinguishing between diffuse adult granulosa cell tumor (mutation present) and cellular fibroma (mutation absent).
FOXL2 mutation was present in 44 out of 47 adult granulosa cell tumors (94%), in 3 out of 8 Thecomas (37%), in 1 out of 10 Sertoli-Leydig cell tumors (SLSTs) (10%) and in 3 out of 5 undifferentiated-SCSTs (Und-SCSTs) (60%).
FOXL2 immunoexpression has recently been found in sex cord stromal tumors of the ovary, including granulosa cell tumors, Sertoli-Leydig cell tumors, thecomas, and fibromas, but mutations have been identified mostly in adult granulosa cell tumors.
FOXL2 ctDNA mutations were detected in the plasma of 12 of 33 AGCT patients (36%), with both primary (6 of 17, 35%) and recurrent (6 of 31, 19%) tumors.
CA125 levels were above 35IU/l in 25% of AGCT patients and 47.5% of ENDO patients, whereas inhibin B and AMH levels were elevated only in patients with AGCTs.
AMH can be used as a marker of sertoli/granulosa cell tumors and primary ovarian insufficiency in girls with delayed puberty, Turner Syndrome and after treatment with gonadotoxic agents.
APC2-deficiency in these mice resulted in predisposition to granulosa cell tumour (GCT) formation, accompanied by acute tumour-associated WNT-signalling activation and a histologic pattern and molecular signature seen in human adult GCTs.