GATA4 is diagnostically useful for distinguishing primary ovarian mucinous carcinomas from metastatic colorectal adenocarcinomas to the ovary.

Determining the primary origin of an ovarian mucin-producing carcinoma can be challenging at times because some metastases of primary colorectal origin may exhibit gross, microscopic, and/or immunohistochemical features that overlap with those of primary ovarian mucinous carcinomas (OMCs). We hypothesized that GATA binding protein 4 (GATA4) might be a novel, useful marker for differentiating primary OMCs from metastatic colorectal adenocarcinomas to the ovary.