Endometrioid adenocarcinoma arising in uteri with incomplete fusion of Mullerian ducts. Report of three cases

The most common developmental abnormality of the uterus results from failure of fusion of a portion or of the entire length of the lower Mullerian ducts. The incidence of congenital malformations of the upper part of the female genital system in less than 0.2% of the female population. In a selective series such as a hysterosalpingography study, 8.6% of individuals were discovered to have a uterine malformation [1, 2]. If a uterine malformation is identified in childhood it may be part of a polyphenotypic syndrome with genito-urinary tract anomalies [3]. In women without chromosomal abnormalities the most usual malformations consist of incomplete fusion of the Mullerian ducts [4-7]. Etiologic factors include fetal exposure to diethylstil-bestrole or thalidomide, environmental factors and excessive hormonal stimulation during the 10-12th week of fetal development [4-7]. Usually these malformations are not recognized until the reproductive years, when problems of fertility, abortions, fetal deformities, abnormal birth presentations or uterine perforation arise as adverse consequences of these malformations [2]. A number of classifications have been proposed for mullerian anomalies, [8, 9] but the most simple is one presented by Buttram and Gibbons (Table 1). In the case of didelphys uterus the two structures may not be of equal size. Development of a neoplasm in one of the uterine endometrial cavities is an extremely rare event and few reports are encountered in the literature [10-15].