The epithelial cells of ovarian
mucinous carcinomas may sometimes appear similar to those of gastrointestinal or endocervical
mucinous carcinomas, but most are composed of cells that do not suggest any particular derivation. We report four cases of mucinous ovarian
carcinoma in which the cells were entirely or almost entirely endocervical-like. The patients' ages were 34, 43, 44, and 50 years. Two patients had bilateral
tumors confined to the ovaries at initial staging; both also had synchronous
endometrial carcinomas of the mucinous type. The two other patients had unilateral
tumors, both with invasive
metastases in the pelvis and abdomen at initial staging. In one of the latter cases a mullerian (endocervical-like) mucinous borderline
tumor (
MMBT) of the opposite ovary had been removed 5 years earlier, and in this case and two other cases the ovarian
carcinomas had foci resembling
MMBT, suggesting that they may be an invasive counterpart to these
tumors. The six
tumors ranged from 4 to 19 cm; five were grossly cystic with papillary or solid areas, and one was entirely solid. They were composed of closely packed glands,
cysts, and
cysts containing complex papillae. There was abundant intraglandular and intracystic
mucin. The epithelial cells were well differentiated with infrequent mitoses and most were tall with mucinous cytoplasm resembling normal endocervical glandular cells. In three
tumors there also were round to polygonal cells with eosinophilic cytoplasm; endometrioid foci were present in three
tumors and a squamous focus was present in one. One
tumor had a focally infiltrative growth pattern with a desmoplastic stromal reaction; the remaining five
tumors had an exclusively confluent (expansile) pattern of invasion.
Endometriosis was present in residual ovarian tissue adjacent to four
tumors in three patients and had marked epithelial proliferation in three. All patients were treated postoperatively with
chemotherapy and were without clinical recurrence with follow-up intervals of 8 months, 1.2 years, 2.9 years, and 3.8 years. By immunohistochemical analysis the neoplastic epithelium was positive for
estrogen and
progesterone receptor proteins,
vimentin, and
cytokeratin 7, and negative or only focally positive for
carcinoembryonic antigen and
cytokeratin 20, a profile that differs from that of the usual mucinous ovarian
carcinoma and is supportive of a mullerian derivation. As with MMBTs, there was a strong association with
endometriosis, and these
tumors likely arise from
endometriosis, possibly through an
MMBT precursor in some cases. To better understand their clinicopathologic features and pathogenesis, this uncommon variant should be separated from the usual type in future studies of
mucinous carcinomas of the ovary.