Obesity and prognosis in endometrial cancer

OBJECTIVE: We tested the null hypothesis that morbid obesity as measured by the Quetelet index has no influence on survival in endometrial cancer. STUDY DESIGN: A retrospective study of 492 women with endometrial carcinoma was performed. Age, height, weight, Quetelet index, stage, cell type, grade, node status, peritoneal cytologic findings, and depth of myometrial invasion were analyzed for influence on survival. RESULTS: Mean Quetelet index was 34 (range 16 to 89). Quetelet index was <30 in 45% of patients, 30 to 40 in 33%, and >40 in 22%. Five percent of those with a Quetelet index >40 had positive nodes, but 64% of patients with a Quetelet index >40 did not have lymph node sampling done. Lack of sampling of lymph nodes in the entire group had no adverse effect on survival. In a proportional hazards regression model for time from diagnosis to death from disease, grade, node status, myometrial invasion, and stage had highly significant effects. When Quetelet index was analyzed as a continuous variable, as Quetelet index increased, time to recurrence was significantly increased (p = 0.0136), and significance was approached for survival (p = 0.0645). Quetelet index was strongly related to grade (p = 0.013), depth of myometrial invasion (p = 0.031), negative cytologic findings (p = 0.004), and stage (p = 0.011) with obese patients having better differentiated, less invasive tumors of lower stage with negative washings. CONCLUSIONS: Morbid obesity positively affects survival in endometrial carcinoma. This effect is accounted for by the association of obesity with less aggressive disease. Morbid obesity is not associated with increased death from other causes. Lack of sampling of negative lymph nodes does not adversely affect survival.