Endometrial carcinoma is commonly diagnosed as a consequence of abnormal uterine bleeding. In a study published in 1962, it was documented that endometrial cancer may be detected by vaginal pool smears in asymptomatic postmenopausal women.
As a consequence of these observations, a systematic search for occult endometrial carcinoma was initiated in 1979, supported by a contract from the National Cancer Institute. The techniques used in this sutdy and the problems encountered in the diagnosis of occult endometrial carcinoma will be a discussed.
Within 3 1/2 years of this sutdy encompassing 2,586 peri- or postmenopausal women, 16 occult endometiral carcinomas were discovered by direct endometrial sampling. Two carcinomas, missed on initial screening, were subsequently documented in this cohort, for a prevalence rate of 6.96 per 1,000. The incidence date based on follow-up examination of 1,754 women was 1.71 per 1,000 woman-years. An elaborate epidemiologic questionnnaire was evaluated. Contrary to some prevailing views, obesity, hypertension, and diabetes failed to reach statistical significance as risk factors. The only risk factor of statistical value was delay in the onset of menopause past age 49, observed in about 50% of the cohort. It was noted that the adminsitration of estrogens to women in Quetelet Index groups below mean was more likely to be associated with carcinoma than in women in higher Quetlet Index groups but, again, the differece was not statistically signficant.
It was noted that in spite of a active search for endometrial hyperplasias, the rate of these lesions was nearly identical to the prevalence and incidence rates for carcinoma. It was postulated that some, or perhaps most, endometrial carcinomas in postmenopausal women are not preceded by hyperplasia but originate ab initio in the endometrium.