Differences in risk for type 1 and type 2 ovarian cancer in a large cancer screening trial / 부인종양

OBJECTIVE: To investigate the role of previous gynecologic surgery, hormone use, and use of non-steroidal anti-inflammatory drugs on the risk of type 1 and type 2 ovarian cancer. METHODS: We utilized data collected for the Prostate, Lung, Colorectal, and Ovarian cancer screening trial. All diagnosed ovarian cancers were divided into three groups: type 1, endometrioid, clear cell, mucinous, low grade serous, and low grade adenocarcinoma/not otherwise specified (NOS); type 2, high grade serous, undifferentiated, carcinosarcoma, and high grade adenocarcinoma/NOS; and other: adenocarcinoma with grade or histology not specified, borderline tumors, granulosa cell tumors. The odds ratios for type 1, type 2, and other ovarian cancers were assessed with regard to historical information for specific risk factors. RESULTS: Ibuprofen use was associated with a decrease in risk for type 1 ovarian cancer. Tubal ligation and oral contraceptive use were associated with a decrease in risk for type 2 ovarian cancer. A history of ectopic pregnancy was associated with a decreased risk for all ovarian cancers by almost 70%. CONCLUSION: These findings support the hypothesis that carcinogenic pathways for type 1 and type 2 ovarian cancer are different and distinct. The marked reduction in all ovarian cancer risk noted with a history of ectopic pregnancy and salpingectomy implies that the fallopian tube plays a key role in carcinogenesis for both type 1 and type 2 ovarian cancer.

Proliferation of the superficial epithelium of ovaries in senile female rats following oral administration of conjugated equine estrogens

OBJECTIVE: To evaluate the effect of different concentrations of estrogen on the ovarian superficial epithelium in senile female rats. Design: Fifty female rats at 15 months of age and with irregular estrous cycles were selected and randomly divided into five experimental groups containing equal numbers of animals in each: GPROP, control group receiving vehicle only; GE0.05mg, group receiving conjugated equine estrogens (CEE) at a dose of 50 µg/kg; GE0.5mg, group receiving CEE at 500 µg/kg; GE1mg, group receiving CEE at 1 mg/kg; and GE2mg, receiving CEE at 2 mg/kg. The length of treatment was 21 days. After this period, the animals were anesthetized and the ovaries were fixed in 10 percent formaldehyde and processed for routine histology. Histomorphology was analyzed by light microscopy, and histomorphometrics were evaluated using the Imagelab program. RESULTS: In the GPROP and GE0.05mg groups, the superficial epithelium of the ovary had a simple cuboidal shape, and as the estrogen dose increased, the epithelium thickened, with pseudo-stratified or stratified epithelium appearing in the GE2mg group. The animals in the group given the highest estrogen dose (GE2mg) showed the thickest ovarian epithelium and the largest perimeter and surface area of the surface ovarian epithelium (P < 0.01). However, the difference in epithelium thickness between the GE0.5mg and GE1mg groups was only slight. CONCLUSION: Our data suggest that CEE at a dose of 2 mg/kg may induce marked proliferation of rat ovarian epithelium.