Extremely well-differentiated adenocarcinoma ("adenoma malignum") of the cervix.

Eight cases of extremely well-differentiated adenocarcinoma of the cervix were collected for clinicohistopathologic study. The tumors, despite having an innocuous histologic appearance, were characterized by irregular shapes and various sizes of the glands, with intraluminal papillary projections supported by thin connective tissue cores. They showed, in addition, sharp outpouching and distension of the malignant glands by mucin, as well as leakage into stroma. Clinically, such tumors were highly malignant and the prognosis was poor. Six patients died within 3 years following surgical treatment. In six of the eight cases, Feulgen microspectrophotometric DNA measurements disclosed patterns similar to those of normal endocervical glands, except for 4c to 6c aneuploid cells.