BACKGROUND: Pigmented renal cell carcinoma is very rare, and there hav
e been no reports on its cytologic findings. CASE: A 40-year-old femal
e with pigmented renal cell carcinoma had cytologic findings similar t
o those of clear cell type renal cell carcinoma except for the presenc
e of melaninlike brown pigment. CONCLUSION: It is important to recogni
ze that renal cell carcinoma may contain melaninlike brown pigment see
n on cytologic examination of renal aspirates.