Cytokeratin immunostaining in differentiating primary ovarian carcinoma from metastatic colonic adenocarcinoma.

The differentiation of ovarian metastases from colonic carcinoma and primary ovarian carcinoma can be difficult. To assess the utility of cytokeratin 7 and cytokeratin 20 immunostains in this setting, we studied routinely processed, formalin-fixed tissue from 165 ovarian tumors, including 45 serous carcinomas, 40 mucinous carcinomas, 64 endometrioid carcinomas, and 16 metastatic colonic adenocarcinomas with an avidin-biotin immunohistochemical technique. A cytokeratin 7+/cytokeratin 20- immunophenotype was seen in 86% of the endometrioid carcinomas, 27% of the mucinous carcinomas, 40% of the serous carcinomas, and none of the metastatic colorectal carcinomas. Conversely, a cytokeratin 7-/cytokeratin 20+ immunophenotype was seen in 94% of the metastatic colonic tumors, 5% of the mucinous carcinomas, and none of the endometrioid or serous tumors. We concluded that cytokeratin immunostains can be helpful in distinguishing metastatic colonic adenocarcinoma from primary ovarian carcinomas, particularly endometrioid carcinomas. Rare ovarian mucinous carcinomas may show the same immunophenotype as metastatic colonic carcinomas.

Hypoplastic left heart syndrome with male pseudohermaphroditism and bicornuate uterus bicollis.

A 39-week-old phenotypically female infant was born with hypoplastic left heart syndrome and expired on the third day of life. An autopsy revealed the patient to also have male pseudohermaphroditism and uterus bicornis bicollis. The association of hypoplastic left heart syndrome and male pseudohermaphroditism has been reported in only two previous patients.

Lewis X antigen immunostaining in the diagnosis of transitional cell carcinoma.

Immunodetection of the Lewis X antigen has been suggested as a useful adjunct in the diagnosis of transitional cell carcinoma. To determine the specificity of Lewis X antigen immunostaining in this setting, we studied routinely processed, formalin-fixed tissue from 38 transitional cell carcinomas and 42 nonneoplastic urothelial lesions using the P12 monoclonal antibody to Lewis X antigen and an avidin-biotin immunohistochemical technique. Because Lewis X immunostaining of occasional umbrella cells has previously been noted in normal urothelium, staining of umbrella cells was not considered sufficient for a positive reaction in our study. Immunoreactivity for Lewis X antigen was seen in 34 of 38 (89%) cases of transitional cell carcinoma, in three of three cases of urothelial dysplasia, and in 20 of 39 (51%) of the reactive urothelial lesions. We conclude that immunostaining for the Lewis X antigen is not specific in the diagnosis of transitional cell carcinoma.

Utility of cytokeratin immunostaining in separating pulmonary adenocarcinomas from colonic adenocarcinomas.

Adenocarcinomas of uncertain origin are a frequent problem for surgical pathologists. To determine the utility of immunostaining for cytokeratin 7 and cytokeratin 20 in the separation of pulmonary adenocarcinomas from colonic adenocarcinomas, we studied routinely processed, formalin-fixed tissue from 151 of these tumors using commercially available monoclonal antibodies and an avidin-biotin immunohistochemical technique. Used alone, neither cytokeratin 7 immunostaining or cytokeratin 20 immunostaining reliably separated these tumors. However, the immunophenotype of cytokeratin 7 positive/cytokeratin 20 negative was seen in 86% of the pulmonary adenocarcinomas, and in 0% of the colonic adenocarcinomas. Conversely, the cytokeratin 7-negative/cytokeratin 20-positive immunophenotype was seen in 77% of the colonic carcinomas, and in 0% of the pulmonary tumors. In conclusion, cytokeratin 7/cytokeratin 20 immunostaining patterns may be helpful in separating pulmonary adenocarcinomas from colonic adenocarcinomas.