Clinicopathological features in endometrial carcinoma associated with Lynch syndrome in China.

Objective: To study the clinicopathological characteristics of Lynch syndrome-associated endometrial carcinoma in China. Methods: Twenty-seven patients who fulfilled Amsterdam criteria II were classified as having Lynch syndrome-associated endometrial carcinoma (group A), and 331 patients without a family history of cancer were classified as having sporadic endometrial carcinoma (group B). Results: There were 81 malignancies in 27 families with Lynch syndrome-associated endometrial carcinoma, including colorectal cancer (24.7%), endometrial carcinoma (21.0%), and liver (12.3%), stomach (9.9%), lung (6.2%), and breast (6.2%) cancers. Mean age at the time of diagnosis was 49.7 years in group A and 56.3 years in group B ( P = 0.004). Second primary cancers occurred in 33.3% of patients in group A and 5.1% in group B ( P = 0.000). The most common second primary cancers were colorectal cancer (44%) and ovarian cancer (22%). The percentage of obese patients was higher in group A ( P = 0.013). There was no difference between the 2 groups in incidence of diabetes mellitus or hypertension or in histological type and International Federation of Gynecology and Obstetrics stage. The 5-year survival rates for groups A and B were 96.2% and 79.6%, respectively. Prognosis for group A was better than for group B ( P = 0.045). Conclusions: Some clinicopathological features of Lynch syndrome-associated endometrial carcinoma, such as early onset and multiple primary carcinomas are similar in the Chinese and American/European populations. However, the Chinese population had a unique family cancer distribution that included lung and breast cancers. Well-differentiated grade and good prognosis imply better biobehavior of Lynch syndrome-associated endometrial carcinoma in the Chinese population.