ENDOMETRIAL CANCER IN A COHORT SCREENED FOR BREAST-CANCER

In a cohort of 25,000 women aged 40-65 years at intake in a periodic s creening programme for breast cancer the occurrence of endometrial can cer was studied during a follow-up period of up to 18 years, The autho rs examined whether they could confirm the existence of a number of re lationships between this cancer and some reproductive and anthropometr ic factors which had been found in several case-control studies and in a few cohort studies, A comparison was made between 147 cases of endo metrial cancer occurring during the period of follow-up and a random s ample of 900 women taken from the cohort (334 being premenopausal and 566 postmenopausal on the day of intake), An inverse relationship betw een number of children and endometrial cancer risk was found in the ol der group; the excess risk among nulliparous women was stronger in mar ried than in single women, Late age at menopause (after age 52) was as sociated with increased risk, Use of oestrogenic drugs on day of intak e for alleviating perimenopausal complaints(reported in 8% of women) i ncreased risk, especially in the younger group, Body weight was positi vely associated with risk (with an odds ratio of 4 in those over 80 kg ) among postmenopausal women, Because there appeared to be a moderatel y strong risk associated with tall height, especially among postmenopa usal women, Quetelet's index performed less well. than body weight its elf, Nevertheless, subscapular and triceps skinfold thicknesses confir med an effect of fatness on risk, These results are discussed with ref erence to other epidemiological studies, in particular two cohort stud ies from Norway, The effect of height, convincingly shown by Tretli an d Magnus in 1990, is explained in a way which does not assume causal m echanisms operating at a young age: absolute fat mass rather than rela tive weight is regarded as the main determinant of risk in postmenopau sal women.