Hereditary ovarian cancer occurs in two forms:
(i) Hereditary breast ovarian cancer syndrome(BOC) is observed in 80–95 percent cases of all familial ovarian cancers. BRCA1 (chromosome 17q) and BRCA2 (chromosome 13q) gene mutations are observed in majority of such cases (serous not mucinous carcinoma). These patients present at an earlier age.
(ii) Hereditary nonpolyposis colorectal cancer (HNPCC)—is an autosomal dominant transmission. Women with HNPCC (Lynch II syndrome) have life time risk of about 50% for endometrial cancer and 12% for ovarian cancer. The risks of other cancers like genitourinary in addition to HNPCC are high. It is due to mutations in three DNA mismatch repair genes (MLH1, MSH2 and MSH6). However, majority of epithelial ovarian cancers are not familial or hereditary. Familial cancer account for less than 10 percent of all ovarian cancers.
PATHOLOGY OF OVARIAN TUMOURS: - general considerations: Malignant epithelial tumors constitute about 90 percent of all primary ovarian carcinomas. The nonepithelial malignant tumors such as gonadal stromal or germ cell tumors are indeed rare, present special problems in extremes of age and are of pathologist’s curiosity. These will be dealt separately. Thus, in the discussion to follow, only the malignant epithelial tumors will be described.
Primary epithelial: Malignant epithelial tumors include both cystic and solid types. These are bilateral in about 50 percent. Cystic is more common than solid. These may arise de novo as malignant or more commonly, they result from malignant changes of benign cystic tumors. Endometrioid carcinoma is associated with endometrial carcinoma in 20 percent and ovarian endometriosis in 10 percent cases. In less than 5 percent, it may arise from the endometrial cyst.
Naked eye appearances: The wall of the cystic tumor becomes shaggy. There may be papillary projection at places. Cut section shows solid areas with hemorrhage at places. The papillae become friable, the base becomes broad and indurated. In mucinous type, it is filled up with gelatinous material.
Solid: It attains a moderate size. The external surface is smooth and often lobulated. Subserous blood vessels may be prominent. Cut section shows greyish granular appearance, at times brain-like. There may be irregular cystic spaces due to necrosis. Microscopic appearance reveals adenocarcinoma or carcinoma without adenomatous pattern.
The medicines that can be thought of use are: -