Spontaneous regression of bilateral hilar lymphadenopathy in renal cell carcinoma

A 26-year-old woman presented with a spontaneous regression of bilateral hilar lymphadenopathy, simulating the natural course of acute sarcoidosis. Several months later the lymph nodes reappeared and finally a metastatic renal cell carcinoma was found. The need for histological confirmation in the diagnosis of sarcoidosis is discussed.