CYTOLOGIC DIAGNOSIS OF A PRIMARY PURE OAT-CELL CARCINOMA OF THE BLADDER IN VOIDED URINE - A CASE-REPORT

BACKGROUND: The urinary bladder is an uncommon site for primary oat ce ll carcinoma, with as few as 30 histologically diagnosed cases describ ed in the literature. The first reported cytologic diagnosis was made in 1991. CASE: A 76-year-old female presented with gross hematuria. Vo ided urine cytology showed small, dark cells with little visible cytop lasm and coarse chromatin. Subsequent histopathologic, immunopathologi c and electron microscopic studies confirmed the diagnosis of primary oat cell carcinoma. CONCLUSION: The diagnosis of oat cell carcinoma is well recognized in respiratory cytology. The same cells found in a ur inary specimen may suggest a primary oat cell tumor in conjunction wit h negative clinical and radiologic investigations for a primary tumor elsewhere.