Endometrial adenocarcinoma histologic subtypes: clinical and pathologic profile.

All cases of endometrial adenocarcinoma treated at the Geisinger Medical Center from January 1970 to June 1980 were retrospectively reviewed in an attempt to elucidate the clinical and pathologic profiles of the various histologic subtypes. Complete clinical and pathologic data was available in 418 cases of stage I endometrial adenocarcinoma. The frequency of the histologic subtypes were adenocarcinoma 66%, adenoacanthoma 16%, adenosquamous 5%, papillary 8%, clear cell 3%, and secretory 2%. Absolute 5-year survival was adenocarcinoma 88%, adenoacanthoma 91%, adenosquamous 62%, papillary 63% (P less than 0.01), clear cell 43% (P less than 0.001), and secretory 89%. When comparing the clinical and pathologic profile of the various histologic subtypes, adenosquamous (52%, P less than 0.001) and clear cell (43%, P less than 0.05) were associated with the highest percentage of grade 3 differentiation. Adenosquamous (38%, P less than 0.05) and clear cell (36%) also had the highest percentage of deep myometrial invasion. Papillary subtype (46%, P less than 0.05) was associated with the highest percentage of nulliparity. There was no difference among the subtypes when comparing menopausal status, exogenous estrogen, obesity, hypertension, diabetes, or uterine size. In summary, (1) adenocarcinoma and adenoacanthoma are the most frequent subtypes; (2) adenosquamous, papillary, and clear cell have decreased 5-year survival; (3) the decreased 5-year survival in adenosquamous and clear cell subtypes appears to be associated with increased grade 3 differentiation and deep myometrial invasion while the poor prognosis associated with papillary subtype was not related to grade or myometrial invasion.