Endometrial ca, acute myeloid leukemia: activity, obesity linked to cancer risk in women.(Gynecology)

ORLANDO, FLA. -- A reduced risk for endometrial cancer was linked to increased physical activity in two separate reports at the annual meeting of the American Association for Cancer Research.

A third report linked obesity to an increased risk of acute myeloid leukemia in women.

Higher physical activity and lower body mass index (BMI) are markers for people with relatively little insulin resistance and hyperinsulinemia. Hyperinsulinemia has been hypothesized to promote the appearance and growth of certain cancers through effects on hormones and growth factors, Charles E. Matthews, Ph.D., said while presenting a poster at the meeting.

Hormones that may increase with inactivity and obesity include insulin-like growth factor and leptin, which may support the growth of myeloid cells, Julie A. Ross, Ph.D., said while presenting a different poster.

The study by Dr. Matthews analyzed physical activity information collected by interviews with 832 women with endometrial cancer and 846 matched controls during 1997-2001 in Shanghai, China. The interviews collected information on regular exercise during adolescence and as adults. Among the 1,678 women in the study, 614 were premenopausal and 1,064 were postmenopausal.

Women who reported having regular exercise both as adolescents and as adults had a 37% lower incidence of endometrial cancer, compared with women who had no regular exercise during either period--a statistically significant difference. The risk reduction was similar regardless of menopausal status, reported Dr. Matthews, an epidemiologist at Vanderbilt University in Nashville, Tenn.

Women who regularly exercised either during adolescence or as adults also had a reduced risk of endometrial cancer, but the size of the reduction was much less than that in the women who were active during both stages of life.