Expression of cytokeratin 7 in simultaneous mucinous tumors of the ovary and appendix

Mod Pathol. 1995 Jun;8(5):573-6.


Cytokeratin 7 (CK-7) is a simple epithelial keratin that may be used to investigate the site of origin of adenocarcinomas. In fact, CK-7 is present in ovarian epithelial neoplasms but is generally absent in colonic carcinomas. This pattern of CK-7 expression may aid in elucidating the genesis of mucinous tumors occurring simultaneously in the ovary and appendix, accompanied by psuedomyxoma peritonei. Five such cases were immunostained with anti-CK-7, and all showed a concordant staining pattern of the appendiceal, ovarian, and peritoneal lesions. Two cases showed a negative reaction for CK-7 and thus would appear to represent ovarian and peritoneal metastases from an appendiceal primary tumor. Three cases were CK-7 positive, and the nature of these mucinous lesions remains open to debate; they may either represent independent primary tumors or originate from the appendix. For comparison, five Stage I mucinous borderline tumors of the ovary and their normal appendices were also stained with anti-CK-7. These ovarian tumors were all CK-7 positive, whereas the appendices were negative. It is concluded that CK-7 is capable of distinguishing a group of tumors that can reliably be classified as primary appendiceal neoplasms metastatic to the ovaries and peritoneum.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Appendiceal Neoplasms / chemistry
  • Appendiceal Neoplasms / pathology*
  • Cystadenocarcinoma, Mucinous / chemistry
  • Cystadenocarcinoma, Mucinous / pathology*
  • Female
  • Humans
  • Immunohistochemistry
  • Keratins / analysis*
  • Middle Aged
  • Ovarian Neoplasms / chemistry
  • Ovarian Neoplasms / pathology*
  • Peritoneal Neoplasms / pathology*
  • Pseudomyxoma Peritonei / metabolism
  • Pseudomyxoma Peritonei / pathology*


  • Keratins