Cdx2, cytokeratin 20, thyroid transcription factor 1, and prostate-specific antigen expression in unusual subtypes of prostate cancer

Leite, Katia Ramos Moreira; Mitteldorf, Cristina A.T.S.; Srougi, Miguel; Dall'Oglio, Marcos F.; Antunes, Alberto A.; Pontes, José; Camara-Lopes, Luiz Heraldo

doi:10.1016/j.anndiagpath.2007.11.001

« Previous Next »Annals of Diagnostic Pathology
Volume 12, Issue 4 , Pages 260-266, August 2008

Cdx2, cytokeratin 20, thyroid transcription factor 1, and prostate-specific antigen expression in unusual subtypes of prostate cancer

Katia Ramos Moreira Leite, MD
- Laboratory of Surgical and Molecular Pathology, Hospital Sirio Libanes, São Paulo 01308-050, Brazil
- Laboratory of Medical Investigation, Urology—LIM 55, Medical School USP, São Paulo 01246-903, Brazil
- Corresponding author. Rua Adma Jafet, 91, 01308-050 São Paulo, Brazil. Tel.: +55 11 3155 0249; fax: +55 11 3231 2249.
Cristina A.T.S. Mitteldorf, MD
- Laboratory of Surgical and Molecular Pathology, Hospital Sirio Libanes, São Paulo 01308-050, Brazil
Miguel Srougi, MD
- Laboratory of Medical Investigation, Urology—LIM 55, Medical School USP, São Paulo 01246-903, Brazil
Marcos F. Dall'Oglio, MD
- Laboratory of Medical Investigation, Urology—LIM 55, Medical School USP, São Paulo 01246-903, Brazil
Alberto A. Antunes, MD
- Laboratory of Medical Investigation, Urology—LIM 55, Medical School USP, São Paulo 01246-903, Brazil
José Pontes Jr, MD
- Laboratory of Medical Investigation, Urology—LIM 55, Medical School USP, São Paulo 01246-903, Brazil
Luiz Heraldo Camara-Lopes, MD
- Laboratory of Surgical and Molecular Pathology, Hospital Sirio Libanes, São Paulo 01308-050, Brazil

published online 07 April 2008.

Abstract

There are some unusual histologic variants of prostate carcinoma, including mucinous, signet-ring cells, and ductal carcinomas that can metastasize in a problematic way and simulate lung, colorectal, or bladder primaries. Currently, antibodies that are organ-specific have been used in the routine surgical pathology practice. Our aim is to study the profile of expression of Cdx2, thyroid transcription factor 1 (TTF1), and cytokeratin 20 (CK20) in prostate cancer with unusual histologic finding. Twenty-nine prostate adenocarcinomas with unusual histologic findings were submitted to immunohistochemistry with prostate-specific antigen (PSA), CK20, Cdx2, and TTF1 antibodies. There were 7 mucinous, 5 ductal, 2 signet-ring cells, and 15 usual acinar adenocarcinomas with focal mucinous differentiation. To compare the results with usual acinar adenocarcinomas, we studied 10 primary and their respective lymph node metastases in a tissue microarray, 2 unusual metastatic adenocarcinomas, and 6 usual acinar high-grade carcinomas. For tumors with special histologic finding, Cdx2 was expressed by 9 (31.0%) mucinous, signet-cell, or with focal mucinous differentiation. Thyroid transcription factor 1 was moderately positive in mucinous differentiation areas of 2 (6.9%) adenocarcinomas. Cytokeratin 20 was expressed by 9 (31.0%) tumors, among them, 3 ductal adenocarcinomas. Prostate-specific antigen was positive in 28 (96.6%) cases and negative in 1 ductal adenocarcinoma. There was only 1 worrisome ductal adenocarcinoma that was strongly CK20 positive and PSA negative. Almost one third of mucinous prostate carcinomas express Cdx2. Cytokeratin 20 can be positive also in one third of prostate carcinomas, especially the ductal type. Pathologist should be alert when evaluating immunohistochemical profiles of unusual histologic findings of prostate cancer, mostly in distant sites.

Keywords: Cdx2, Cytokeratin, Immunohistochemistry, Prostate cancer, PSA, TTF1