Colloid Carcinoma of the Uterine Cervix

Abstract

Colloid carcinoma, characterized by the presence of a large amount of extracellular mucin that results in the formation of mucous lakes with a relative paucity of neoplastic glandular cells within them, is extremely rare in the uterine cervix. Herein, we report an additional case of colloid carcinoma of the cervix and discuss the immunohistochemical characteristics and histogenesis of this extremely rare tumor. A 47-year-old Japanese female without any history of carcinomas was found to have a bulky mass in the cervix. Biopsy from the cervix revealed adenocarcinoma; subsequently, total hysterectomy was performed. Histopathologic study demonstrated that columnar or cuboidal neoplastic glandular cells forming cribriform or tubular structures floated within the mucous lakes involving almost the entire layer of the cervical wall. Adenocarcinoma in situ (AIS) component was also observed. Immunohistochemically, tumor cells of the colloid carcinoma were positive for cytokeratin 7, MUC5AC, MUC6, and p16 (diffuse), but negative for cytokeratin 20, MUC2, and cdx-2. In addition, human papillomavirus 16 was detected in both colloid carcinoma and AIS components. This is the first reported case of endocervical type colloid carcinoma, and the second documented case of cervical colloid carcinoma with immunohistochemical analyses of mucin. The present case had an endocervical type AIS component, which suggests that AIS may be a precursor lesion of colloid carcinoma. Moreover, this case clearly demonstrates that the occurrence of cervical colloid carcinoma correlates with high-risk human papillomavirus.

Colloid Carcinoma of the Uterine Cervix and Its Immunohistochemical Analysis: A Case Report

“…Colloid adenocarcinoma of the cervix is a very rare tumor and its histopathologic classification is not clear. In the literature, only two cases were reported as colloid carcinoma of the cervix [ 1 , 2 ]. It is a unique subtype due to the phenotype of contained mucus, and its prognosis is controversial.…”

“…Colloid carcinoma is a subgroup of the intestinal type [ 1 , 6 ]. On the other hand, colloid tumor is also considered as a heterogeneous group of tumors which might have intestinal and endocervical phenotypes [ 1 , 2 ].…”

“…MUC5AC is a gastric foveolar epithelial type of mucin. MUC6 is a pyloric gland type of mucin and both types were expressed by endocervical cells while MUC2 is an intestinal type of mucin and not expressed by endocervical cells [ 1 , 2 , 7 - 9 ]. When an epithelium undergoes malignant transformation, the mucin genes can undergo aberrant expression causing reduced production of an expected mucin and/or production of a structurally different and unexpected mucin within the transformed epithelium [ 8 ].…”

“…Immunohistochemical analyses on different types of mucins have been conducted in pancreatic, gastrointestinal and endocervical tumors. While MUC2 is not expressed in normal endocervical epithelial cells, it is expressed in endocervical adenocarcinomas [ 2 , 8 ]. It is observed that de novo MUC2 is expressed in neoplastic endocervical glands and postulated that MUC2 expression may accompany neoplastic transformation of endocervical glands [ 7 ].…”

“…In the literature, only two colloid carcinoma cases with immunohistochemical features have been reported [ 1 , 2 ]. One of the cases was reported as pure colloid carcinoma [ 2 ], while the second case was reported as colloid carcinoma with endocervical type adenocarcinoma in situ component [ 2 ].…”