INTRODUCTION
Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant disease characterized by susceptibility to the development of cutaneous leiomyomas, uterine leiomyomas, and renal cell carcinoma (RCC). HLRCC is caused by heterozygous germline mutations in thefumarate hydratase (FH ) gene, and the incidence of RCC inFH mutation carriers is estimated to be around 15%.1–3 RCC in HLRCC usually occurs in adolescents to middle-age adults, and the median age of RCC diagnosis is 40–44 years.2, 3 FH-deficient RCC is often diagnosed at an advanced stage with metastases even if the primary tumor size is small. There is no standard treatment for FH-deficient RCC with metastasis. The mean survival of individuals diagnosed with advanced-stage FH-deficient RCC was significantly shorter than that of individuals diagnosed with early-stage RCC (15.8 vs. 80.8 months).3 Since only diagnosis and early-stage intervention can improve disease-related mortality, regular abdominal magnetic resonance imaging (MRI) is recommended for carriers of FH mutations.1Based on the prior report of the then-youngest patient diagnosed to date, 4 it is recommended that screening start around age 8–10.1 Here, we report a male with HLRCC and very early onset RCC at seven years old. This report may affect the starting age for future RCC-surveillance programs for patients with HLRCC.