OVARIAN CANCER OVERVIEW
Ninety percent of ovarian cancers represent a collection of “epithelial tumours” that increase in incidence with age, with patients diagnosed at a median age of 63 years. Stromal tumours represent less than 10% of malignant tumours arising in the ovary and typically present with symptoms related to sex hormone production. The remaining tumours are germ cell tumours that occur in adolescents and young adults.
Lifetime risk of epithelial ovarian cancer is approximately 1 in 85. Risks are lower in multiparous women and those who have taken oral contraceptives. Risks are significantly higher in women with germline mutations in BRCA1 or BRCA2 or other DNA mismatch repair genes.
Epithelial and stromal tumours spread primarily by exfoliation of cells into the peritoneal cavity whereas germ cell tumours tend to spread by lymphatics or haematogenously.
Patients should usually undergo surgical resection of ovarian tumours with comprehensive surgical staging. Most women with epithelial ovarian cancer present with advanced disease and aggressive surgical cytoreduction is recommended. Approximately 10% of these patients will also present with malignant pleural effusions. Comprehensive surgical staging is recommended for stromal and germ cell tumours although the role of lymphadenectomy is unclear when there is no gross lymphadenopathy.
Epithelial tumours are typically treated with carboplatin and paclitaxel as well as maximal surgical cytoreduction. A high percentage of women will experience a complete clinical remission; however, the majority who present with advanced disease will relapse within a few years. Median survivals for women with advanced disease are approaching 5 years. Germ cell tumours typically are treated with bleomycin, etoposide, and cisplatin in regimens initially described in the management of testicular carcinoma with the majority of women cured of disease.
Women with early-stage disease typically receive adjuvant therapy with regimens similar to those used for advanced disease.
Most women with epithelial cancer will develop recurrent intraperitoneal tumour. Tumors recurring greater than 6 to 12 months after the prior exposure to platinum are often retreated with platinum-based therapy. Patients with rapid recurrence after platinum therapy may be palliated with a variety of drugs, including liposomal doxorubicin, topotecan, and gemcitabine. In addition, bevacizumab has significant activity in the management of recurrent disease.
Most women with recurrent epithelial cancer will eventually have significant bowel dysfunction. Optimal management often requires a multidisciplinary approach.