Table 1

World Health Organization classification of ovarian sex cord-stromal tumors

Tumor type
Pure stromal tumors
 Fibroma4% of all ovarian tumors8
 Cellular fibroma
 Thecoma0.51% of all ovarian tumors16
 Luteinized thecoma associated with sclerosing peritonitis
 Signet ring stromal tumor
 Sclerosing stromal tumor5% of all sex cord stromal tumors7
 Microcystic stromal tumor
 Leydig cell tumor
 Steroid cell tumor
 Steroid cell tumor, malignant
Pure sex cord tumors
 Adult granulosa cell tumor95% of all granulosa cell tumors68
 Juvenile granulosa cell tumor5% of all granulosa cell tumors68
 Sertoli cell tumor
 Sex cord tumors with annular tubules1.4% of all sex cord-stromal tumors81
Mixed sex cord stromal tumors
 Sertoli–Leydig cell tumors<0.5% of all ovarian tumors84
 Well differentiated
 Moderately differentiated
  With heterologous elements
 Poorly differentiated
  With heterologous elements
  With heterologous elements
 Sex cord-stromal tumor, not otherwise specified