Papillary renal cell carcinoma with lipocyte-like cells: a rare morphological variant or an indication of aggressiveness?

Papillary renal cell carcinoma (PRCC) is the second most common carcinoma of the kidney, which is classified into two types. Type 1 displays single layer of cells with scanty pale cytoplasm and type 2 has pseudostratified high-grade nuclei with eosinophilic cytoplasm. Recently, apart from these two types, oncocytic PRCC and clear-cell PRCC have been described. To the best of our knowledge, lipocyte-like cells have not yet been reported to accompany any subtypes of renal cell carcinoma. Herein, we report a case of PRCC with lipocyte-like cells and sarcomatoid features. Lipocyte-like cells might represent a special type of PRCC or this feature may be an indication of poor prognosis regarding its association with sarcomatoid change.