Lymph nodal involvement by renal angiomyolipoma.

Angiomyolipoma of the kidney is a clonal neoplasm, apparently part of a family of neoplasms derived from perivascular epithelial cells. A 40-year-old woman presented with right flank pain and an otherwise non-significant medical history. An abdominal computed tomography scan revealed an 18 cm solid mass in the mid-portion of the right kidney and multiple perihilar lymph nodes. Presumptive diagnosis was renal cell carcinoma. Right radical nephrectomy and a perihilar lymph node dissection was performed through a Chevron incision for the anticipated diagnosis of renal adenocarcinoma. The renal tumor was diagnosed as angiomyolipoma and a component was identified pathologically in a dissected lymph node. There was no evidence of tumor recurrence in the follow-up period of eight years. The consensus from other studies suggests that this phenomenon is a manifestation of the multicentric nature of angiomyolipoma, rather than due to metastasis. Genetic studies may resolve this question in the future.