Local Tumor Bed Recurrence Following Partial Nephrectomy in Patients with Small Renal Masses

Purpose We examined the incidence, characteristics and treatment of patients with tumor bed recurrence after partial nephrectomy. Materials and Methods We retrospectively reviewed the charts of 2,256 patients with sporadic small renal masses treated with partial nephrectomy between 2000 and 2014. Local tumor bed recurrence was strictly defined as detection of a new enhancing lesion 1) specifically in the surgical defect or 2) in the same region (eg lower pole) as the partial nephrectomy site. To determine differences in multiple characteristics 44 patients (1.9%) with local recurrence were compared to 163 randomly selected patients who underwent partial nephrectomy with no recurrence. Results Patients with local tumor bed recurrence were more likely to have a solitary kidney (27% vs 4%, p <0.01) and bilateral disease at presentation (23% vs 10.4%, p = 0.02) compared to the group with no recurrence. Positive margins were found in 15.9% of local tumor bed recurrences compared to 3% of the control group (p <0.01). Median time between partial nephrectomy and the detection of local tumor bed recurrence was 23 months (range 2 to 107). Male gender, a solitary kidney at partial nephrectomy, positive surgical margins, multiple tumors, and higher nephrometry score and pathological stage were associated with local tumor bed recurrence. Conclusions Local tumor bed recurrence after partial nephrectomy is associated with several preoperative factors, including multiple tumors and a solitary kidney, as well as intraoperative and postoperative factors such as a positive surgical margin and higher pathological stage.