acid-phosphatase and Adenocarcinoma--Clear-Cell

Clear cell adenocarcinoma of the lower urinary tract is a rare neoplasm whose histogenesis has not been thoroughly investigated. We have examined six specimens of clear cell adenocarcinomas collected from three institutions using histological, histochemical, and immunohistochemical techniques. Results indicate that almost all clear cell adenocarcinomas of this region express morphological and antigenic features, suggesting müllerian differentiation, and that müllerian differentiation is not a feature of either nonclear cell adenocarcinomas or normal female paraurethral glands. Including the authors' six specimens, 46 specimens have been reported in the available English literature. The accumulated experience confirms the initial impression that these tumors develop predominantly in the urethras of women and occur over a wide age range. Despite high stage at diagnosis, most patients have been alive with no evidence of disease when reported, a prognosis that seems to apply regardless of length of follow-up.

Topics: Acid Phosphatase; Adenocarcinoma, Clear Cell; Adult; Aged; CA-125 Antigen; Female; Humans; Immunoenzyme Techniques; Immunohistochemistry; Male; Middle Aged; Prostate-Specific Antigen; Urethra; Urethral Neoplasms; Urinary Bladder Neoplasms

Cytoplasmic clarity is a histological feature of normal prostatic secretory cells, but in this study, tissue fixation in strong (>2.5%) glutaraldehyde dramatically altered cytological staining. Secretory cytoplasm appeared red and granular on routine stains because of myriad intensely staining eosinophilic granules (PSG). Immunostaining for prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) showed their exclusive localization to the PSG. Electron microscopy confirmed these findings and also showed that after fixation in many agents, including formaldehyde, PSG appeared empty, accounting for the artefactual "clear cell" appearance on light microscopy. PSG were most densely concentrated apically in a bud-shaped luminal compartment in which cytokeratin was selectively absent. Normal exocrine secretion was visualized as detachment of apocrine buds or their in situ disintegration. Distinctively in dysplasia and almost all carcinomas, PSG were rare to absent, and proteases were free in the cytoplasm, often concentrated beneath the apical membrane. The apocrine compartment was absent, with no observed secretory mechanism. Tumor cells had dark amphiphilic cytoplasm after all fixatives. This provided a reliable method of distinguishing malignant from benign glands in tissues fixed in strong glutaraldehyde. Clear cell carcinomas, whose cytoplasm mimicked routinely fixed normal secretory cells, surprisingly had almost no PSG. Instead, their "granules" were lipid-filled vacuoles reflecting a secretory pathway not seen in normal cells, dysplasia, or the common "dark cell" carcinomas. These observations may define two distinctive biological pathways of prostate cancer evolution and may facilitate diagnostic decisions on needle biopsy samples.

Topics: Acid Phosphatase; Adenocarcinoma, Clear Cell; Cell Transformation, Neoplastic; Cytoplasmic Granules; Epithelial Cells; Humans; Immunoenzyme Techniques; Male; Precancerous Conditions; Prostate; Prostate-Specific Antigen; Prostatic Neoplasms

A case of clear cell adenocarcinoma arising from the female urethra is described. Histologically, solid and glandular areas consisted of clear cells. The tumor cells stained positively with antibodies to prostate-specific antigen and prostatic acid phosphatase, suggesting that the clear cell adenocarcinoma arises from the female paraurethral duct, rather than embryonic remnants.

Topics: Acid Phosphatase; Adenocarcinoma, Clear Cell; Antibodies; Female; Humans; Male; Middle Aged; Prostate; Prostate-Specific Antigen; Staining and Labeling; Urethral Neoplasms