A case of
alpha-fetoprotein (AFP) producing
endometrial carcinoma in a 60-year-old Japanese woman is presented. The patient complained of abnormal
vaginal bleeding of 10 days' duration. On admission a uterine corpus mass and high serum AFP concentration (31950 ng/mL) was noted. There was no tumorous lesion in any other organ radiographically and endoscopically. Histologically, the biopsy specimen taken from the uterine mass showed a poorly differentiated
endometrial carcinoma and a radical
hysterectomy was subsequently performed. The postoperative serum AFP value transiently decreased with
chemotherapy, however, lung
metastases were found and the patient died 12 months following surgery. The resected uterus had a necrotic
tumor, 6 x 5 x 4 cm in size, filling the endometrial cavity, characterized by exophytic growth with infiltration in the myometrium. Histologically, the
tumor was composed of the main
medullary carcinoma area with microcysts and admixed small areas of well-differentiated
endometrioid adenocarcinoma, accompanied by a smooth transition with one another. In both the areas, the
tumor cells had immunoreactive AFP, alpha-1-antitripsin,
albumin,
transferrin,
carcinoembryonic antigen, CA19-9, and
epithelial membrane antigen. There was no histologic evidence for a
germ cell tumor. Based on these findings, this uterine corpus
tumor was regarded as hepatoid variant of
endometrial carcinoma. Although the histogenesis remains controversial, we assume the hypothesis that the
tumor may arise in the endometrium per se in association with abnormal differentiation of muellerian duct elements.