Neoplasm to neoplasm metastasis. A renal oncocytoma with metastatic bronchogenic carcinoma

An unusual case of metastasis of neoplasm to a benign neoplasm is reported. The initial malignancy, a small-cell bronchogenic carcinoma, was found to have metastasis to a renal oncocytoma. A review of the literature indicates, according to our knowledge, no similar case.