LIPOLEIOMYOMATOUS TUMORS OF THE UTERUS - A HETEROGENEOUS GROUP - HISTOPATHOLOGICAL STUDY OF 5 CASES

Five surgical cases of lipoleiomyomatous tumor of the uterus were stud ied histopathologically. All the patients were postmenopausal. Three t umors had arisen in the corpus, and the remaining two in the cervix. I n four of five cases, tumors consisted of smooth muscle tissue admired with varying amounts of mature adipose tissue, which did not show cyt ological atypism. In the remaining single case, the tumor contained, i n addition to smooth muscle tissue and fibro-adipose tissue, many anom alous arterial blood vessels, which showed an irregular, tortuous appe arance resembling that found in renal angiomyolipoma. From the histopa thological findings and a review of the relevant literature, it was co nsidered that lipoleiomyomatous tumor of the uterus is not a single hi stopathological entity but is composed of two distinct neoplasms with different histogenesis; that is, 'lipoleiomyoma' and 'angiolipoleiomyo ma'. While the latter tumor is most likely of a choristomatous nature, the former probably arises from 'lipomatous' metaplasia of a pre-exis ting leiomyoma.