Purpose: Renal angiomyolipoma (AML) is a benign neoplasm that may grow massive in tuberous sclerosis (TS) patients. The aim of this study was to document the characteristics of renal AML in Japanese TS patients.
Methods: Medical records of 29 TS patients followed up at the authors' center were reviewed for the presence, size, symptom, and treatment of renal AML.
Results: Twenty-four patients screened for renal AML were subdivided into 4 groups: group 0 (n = 8), no mass; group 1 (n = 5), AML less than 1 cm in diameter; group 2 (n = 4), AML 1 to 4 cm in diameter; group 3 (n = 7), AML greater than 4 cm in diameter. When present, AML always affected both kidneys and were multiple. All patients in groups 1 and 2 were symptom free, and the tumors seemed stable in size. All tumors in group 3 grew progressively causing various symptoms. Total or partial nephrectomy or transarterial embolization was performed in 5 patients with limited success.
Conclusions: AML in TS patients can be stable or aggressive. Pediatric surgeons aware of this problem should be involved in a follow-up program.