Granulosa celltumor of the ovary is a rare type of ovarian cancer that accounts for approximately 2% of all ovarian tumors. This type of tumor is known as a sex cord-stromal tumor and usually occurs in adults. Granulosa cell tumors of the ovary cause higher than normal levels of estrogen in a woman's body. The symptoms of this excess estrogen depend on the woman's menstrual status; the most common symptoms include early puberty for affected young girls, an increase in abdomen size or irregularities of menstrual cycles in premenopausal women, and abnormal uterine bleeding in postmenopausal women. The exact cause of granulosa cell tumors is unknown. Treatment consists of surgery to remove the tumor, and additional treatments may also be used depending on the extent of the tumor.

Surgery is the first step of treating a granulosa celltumor of the ovary and aims to remove as much of the tumor as possible. Additional treatments - such as radiation therapy, chemotherapy, or hormone therapy - may follow surgery depending on the severity and extent of the original tumor, or if the tumor regrows after surgery (a recurrence). These treatments may improve survival or increase the length of disease-free time before a recurrence. After treatments are complete, individuals should continue to have regular visits with their physicians to check for recurrences. These visits should include updating the medical history, a pelvic examination, and possibly blood testing to look for chemicals produced by cancer cells (tumor markers). If there are any suspicious findings during these visits, an imaging test such as a CT scan may be done.

The prognosis is dependent on the severity and extent (stage) of the tumor at the time of diagnosis. The majority of cases of granulosa cell tumor of the ovary are stage I at diagnosis (cancer is still contained within the ovary and has not spread). Stage I granulosa cell tumors of the ovary have been found to have a good prognosis with a 5 year survival rate ranging from 90-100% and a 10 year survival rate ranging from 84-95%.