Very late recurrence of renal cell carcinoma experiencing long-term response to sunitinib: a case report.

Renal cell carcinoma (RCC) is responsible for 4% of all neoplasms in adults and for 80% of all primary renal tumors. Metastatic RCC is resistant to all cytotoxic agents and generally prognosis is poor. However, the clinical behavior of RCC is unpredictable, and late recurrences of disease can occur even after several years from the initial surgical approach, so response to the currently available targeted agents is uncertain, due to the lack of reliable prognostic and predictive factors. We report the case of a patient who developed a metastatic recurrence of RCC 16 years after primary treatment, in spite of metastatic disease at diagnosis. At the time of relapse, the disease showed a surprisingly long-term response to Sunitinib, which is maintained after 74 months of treatment. This case report highlights the unpredictable behavior of RCC and underlines the presence of a subset of patients with metastatic RCC achieving long-term response to Sunitinib, despite poor clinical features. In this subset of patients, an important clinical question arises about the appropriate duration of treatment and the need to continue it indefinitely.