Sex cord stromal tumors account for about 10% of all ovarian tumors are a group of tumors derived from the stromal component of the ovary, which comprises the granulosa, thecal cells and fibrocytes.

Sertoli-Leydig tumors are  rare, accounting for only 0.5% of all ovarian tumors. They are composed of sex cord (Sertoli cells) and stromal (Leydig cells) elements and in 30% of cases they are hormonally active causing symptoms of virilization like hirsutism, hoarseness of the voice, defeminization of the figure and changes in behavior, menstrual disorders such as oligo-menorrhea or even secondary amenorrhea, acne, muscular hypertrophy, clitoral and labia majora hypertrophy. Otherwise the patients present with nonspecific symptoms such as abdominal distension or pain.

CT characteristics: nonspecific, usually unilateral, solid mass or cystic multilocular lesion with mural nodules with heterogeneous marked enhancement (Fig 1 and 2). 

Fibromas are the most common benign ovarian sex cord stromal tumors, they are formed from fibrous tissue and  are usually asymptomatic unless they reach a large size and are usually incidentally found. In some cases they can be associated with ascites and pleural effusion like in the case of Meigs syndrome or be part of the Gorlin-Goltz (nevoid basal cell carcinoma) syndrome.

CT characteristics: usually unilateral and without calcifications, slightly hypo or isoattenuating mass with slow homogeneous contrast enhancement and are associated in 40% of cases with ascites (Fig 3 and 4).

Granulosa theca cell tumors can be divided in two groups : adult type (Fig 5 and 6) and juvenile type(Fig 7 and 8). They arise from granulosa cells which produce sex steroids and peptides for folliculogenesis and ovulation which explains why some patients exhibit hormonal imbalances. Otherwise patients present with abdominal distension, pain and bloating. The evaluation of patients showing the before mentioned symptoms should include laboratory tests and imaging like ultrasound or CT.  

CT characteristics: varied from a solid mass to a multiloculated solid and cystic mass or completely cystic with usually strong and homogeneous enhancement, another key feature that could help with the diagnosis is that the tumor is confined to the ovary, does not have intracystic papillary projections, there is a low chance of peritoneal spread and a thickened endometrium is often seen.