DETECTION OF PROSTATE-SPECIFIC ANTIGEN IN PANCREAS AND SALIVARY-GLANDS - A POTENTIAL IMPACT ON PROSTATE-CANCER OVERESTIMATION

Purpose: We explored the immunohistochemical expression of prostate sp ecific antigen (PSA) in pancreas and salivary glands. Materials and Me thods: We investigated 62 specimens from male and female subjects, rep resenting normal cases and several pathological conditions of pancreas and salivary glands. Two commercially available monoclonal antisera f or PSA and 1 for prostatic acid phosphatase were used. Results: A cons istently positive reaction for PSA and prostatic acid phosphatase, ind ependent of patient sex, was noted in ductal cells of normal pancreas and normal salivary glands, as well as pleomorphic adenoma, adenocarci noma and all oncocytic epithelial cells of Warthin's tumor. Reaction w as absent in normal stromal and acinar cells, and squamous carcinoma. Conclusions: PSA is detectable in normal and cancer tissues far from t he prostate. Therefore, we may not entirely rely on specificity of PSA alone to diagnose metastatic prostate cancer.