Mucinous borderline‐like tumor of the gastrointestinal type arising from mature cystic teratoma of the ovary and its immunohistochemical cytokeratin and mucin phenotype

Abstract

Malignant transformation is rarely seen in the disease course of mature cystic teratoma (MCT) of the ovary. Adenocarcinoma arising from MCT is especially rare. We herein present the case of a premenopausal woman with a mucinous borderline-like tumor arising from a MCT. Based on the histological transition between the borderline-like tumor and gastrointestinal elements of the MCT, we consider that the tumor derived from teratomatous gastrointestinal epithelium. Immunohistochemistry showed that the proliferating mucinous cells were diffusely positive for cytokeratin 20 and partially positive for cytokeratin 7. MUC5AC was partially positive, whereas MUC2 and MUC6 were positive in a small number of tumor cells. The immunophenotype of cytokeratins and mucins in the present case was compatible with malignant transformation of the teratomatous gastrointestinal epithelium.

Claudin‐18 overexpression in intestinal‐type mucinous borderline tumour of the ovary

“…These tumours have been given a variety of names in the literature, and there is a degree of confusion regarding their nomenclature. Some authors refer to IMBTs as ‘gastrointestinal’‐type mucinous borderline tumours . Terms such as ‘seromucinous’, ‘Müllerian type’ and ‘non‐gastrointestinal type’ are used frequently to refer to EMBTs .…”

“…Some authors refer to IMBTs as 'gastrointestinal'-type mucinous borderline tumours. [2][3][4][5] Terms such as 'seromucinous', 'M€ ullerian type' and 'non-gastrointestinal type' are used frequently to refer to EMBTs. 2,3,[5][6][7][8][9] The inconsistency in nomenclature is due primarily to the subjective interpretation of the morphological features of IMBTs and EMBTs by each author.…”

Low Grade Appendiceal Mucinous Neoplasm with Concomitant Ovarian Mucinous Tumor, Mature Cystic Teratoma and Pseudomyxoma Peritonei

“…Th e plethora of confl icting evidence in literature [7][8][9][10][11][12][13][14][15][16][17] and the reconciliation with the fact that both tumors appear similar in morphology and IHC expression regardless of origin raises important research questions. First; if these tumors are so mysteriously similar in morphology and IHC expression, do they have a similar biological behavior?…”