Histological classification in 10 288 cases of ovarian malignant tumors in China
Objective: The histological types of ovarian tumors were investigated and analyzed in China in order to compare with those in other countries, which will benefit to the prevention and treatment of ovarian carcinoma.
Methods: The pathological data from 42 197 cases of ovarian tumors in ten years during 1980 to 1989 were registered according to the WHO classification for ovarian tumors. Some unsure cases pathologically in the previous diagnosis should be reconfirmed according to the WHO classification.
Results: Forty-two thousand one hundred and ninety seven cases of ovarian tumors were selected from all tumors in 21 provinces and 3 major regional cities in China. There were 10 288 (24.4%) malignant tumors in all cases. They were composed by 5 650 (54.9%) cases of epithelial tumors, 1 871 (18.2%) cases of germ cell tumors, 873 (8.5%) cases of sex cord tumors, 1 003 (9.7%) cases of secondary tumors, and 891 (8.7%) cases of other tumors. The malignant tumors constituent ratios were 52.8% and 47.2% respectively in the north and south of the Yangtze River. The histological types of ovarian tumors were about the same ratios, but the malignant tumors were different in Chinese 6 major administrative region and also in the region both north and south of the Yangtze River. The ratio of borderline epithelial ovarian tumors to epithelial carcinoma was 1.0:5.9. Borderline serous cystadenocarcinoma appeared to be similar to borderline mucinous cystadenocarcinoma in frequency. Serous cystadenocarcinoma was found to be the most frequent one in malignant epithelial tumors.
Conclusions: Compared with reports abroad, the different types of malignant ovarian tumors in China represent a different distributive pattern. The malignant epithelial ovarian tumors were lower than that in other countries, while the malignant germ cell tumors and sex cord stromal tumors were 6 and 3 times higher than those abroad, the main metastasizing tumors come from gastroenteric carcinoma.