RESUMO
Chromophobe cell renal carcinoma is an uncommon variety of renal cell carcinoma first described in humans in 1985 by Thoenes and his colleagues. It is a distinct type of renal cancer presumably derived from the intercalated cells of the collecting duct system and exhibiting a better prognosis than other types of renal cell carcinoma. This type of renal cell carcinoma has not been reported in Korean literature. We experienced three cases of chromophobe cell renal carcinoma from surgical pathology files of Dong-A medical center. The patients were a 65-year-old female, a 54-year-old female, and a 50-year-old male who had 8.2x6 cm, 4x2.5 cm and 4.3x3.2 cm sized, yellowish gray, beige to tan colored masses in the kidneys, respectively. Microscopically, the tumor cells were arranged in sheets or nests with delicate intervening vasculature. The cells were voluminous, uniform in appearance and contained finely reticulated cytoplasms delineated by prominent cell borders. With Hale's iron colloid staining the cytoplasm showed positive reaction; with PAS staining the result was negative. Immunohistochemically, the tumor cells showed positive reaction for cytokeratin but negative for vimentin. Electron microscopy showed numerous small, round to oval cytoplasmic vesicles, 150-300nm in size. All the patients received only radical nephrectomy and survived without evidence of recurrence or metastasis during follow-up intervals ranging from 4 months to 5 years.