Type I and II Endometrial Cancers: Have They Different Risk Factors?

Abstract

A B S T R A C T PurposeEndometrial cancers have long been divided into estrogen-dependent type I and the less common clinically aggressive estrogen-independent type II. Little is known about risk factors for type II tumors because most studies lack sufficient cases to study these much less common tumors separately. We examined whether so-called classical endometrial cancer risk factors also influence the risk of type II tumors. Patients and MethodsIndividual-level data from 10 cohort and 14 case-control studies from the Epidemiology of Endometrial Cancer Consortium were pooled. A total of 14,069 endometrial cancer cases and 35,312 controls were included. We classified endometrioid (n ϭ 7,246), adenocarcinoma not otherwise specified (n ϭ 4,830), and adenocarcinoma with squamous differentiation (n ϭ 777) as type I tumors and serous (n ϭ 508) and mixed cell (n ϭ 346) as type II tumors. ResultsParity, oral contraceptive use, cigarette smoking, age at menarche, and diabetes were associated with type I and type II tumors to similar extents. Body mass index, however, had a greater effect on type I tumors than on type II tumors: odds ratio (OR) per 2 kg/m 2 increase was 1.20 (95% CI, 1.19 to 1.21) for type I and 1.12 (95% CI, 1.09 to 1.14) for type II tumors (P heterogeneity Ͻ .0001). Risk factor patterns for high-grade endometrioid tumors and type II tumors were similar. ConclusionThe results of this pooled analysis suggest that the two endometrial cancer types share many common etiologic factors. The etiology of type II tumors may, therefore, not be completely estrogen independent, as previously believed.

Insulin resistance and endometrial cancer risk: A systematic review and meta-analysis

“…We were unable to evaluate the association of insulin resistance in EC patients based on histopathological types due to lack of data stratification by EC type in the included studies. However, both EC types share common etiologic factors [66]. Secondly, data paucity restricted us from accounting for confounding factors such as comorbidities, anthropometry, previous hormone treatments, and lifestyle factors.…”

Prognostic importance of DNA ploidy in non-endometrioid, high-risk endometrial carcinomas

“…Non-endometrioid endometrial carcinomas have a significantly poorer prognosis than endometrioid carcinomas (2). Although the definition of high-risk carcinomas varies, the non-endometrioid histopathological subtypes (e.g., serous carcinoma, clear cell carcinoma and carcinosarcoma) are commonly included in this risk group (19).…”

“…The prognosis of endometrial carcinoma is generally thought to be favorable, predominantly due to detection and diagnosis in the early stages of disease. However, there are subtypes among endometrial carcinomas with poor prognosis and outcome after therapy (2).…”

Role of Laparoscopy in the Treatment of Endometrial Cancer in Women Over 70 Years of Age

“…Заболеваемость и биоло-гическая активность РЭ увеличиваются в течение жиз-ни [4,5], что связано с увеличением числа факторов риска.…”