Seeded Biopsy Tract Recurrence After Extirpative Surgery for Renal Cell Carcinoma.

Background: Renal mass biopsy (RMB) is an increasingly utilized modality in the work-up of patients with suspicious renal masses. Recurrence of renal cell carcinoma (RCC) from biopsy tract seeding is exceedingly rare in the literature. We report a case of such a phenomenon. Case Presentation: Our patient is a 75-year-old Caucasian man and former smoker with a functionally solitary left kidney, initially worked up for gross hematuria and left flank pain. Imaging revealed hydronephrosis and a left renal mass, which was biopsied. Pathology analysis demonstrated clear cell RCC, and a left robotic radical nephrectomy was performed with negative surgical margins. Sixteen months postoperatively, imaging revealed multiple small masses along the biopsy tract, suspicious for recurrence. These were biopsied and pathology analysis confirmed recurrent clear cell RCC. Conclusion: Despite its rarity, biopsy tract seeding is a serious complication of RMB. This warrants thorough counseling and shared decision making between providers and all patients with renal masses planning to undergo a RMB.