Prolonged natural progression from localized to symptomatic renal cell carcinoma.

Surgical excision is the gold standard therapy for clinically localized renal masses. Nevertheless, prognostication of the natural history of untreated renal cell carcinoma (RCC) remains a clinical challenge. While active surveillance (AS) has emerged as a viable treatment option in select patients with localized tumors and significant competing mortality risks, long term follow up data to assess the risk of disease progression are limited. We present a case of a localized, clinical stage T2 renal mass progressing to regional and systemic disease over 6 years, demonstrating that kinetics of disease progression may be prolonged and are yet to be fully understood.