Positive Surgical Margins After Nephron-sparing Surgery

Context: Little is known on the natural history of positive surgical margins (PSMs) in partial nephrectomy (PN). Accumulating data suggest that secondary nephrectomy might not be necessary in all patients with PSMs after PN.

Objective: Provide an overview on incidence and risk factors for PSMs after partial nephrectomy and on the rate of local and distant disease recurrence related to PSMs. We also provide recommendations on how to avoid and how to treat PSMs after PN.

Evidence Acquisition: A nonsystematic literature research was based on Medline, Scopus, and Web of Science queries on these keywords: nephron-sparing surgery, partial nephrectomy/ies, and margin. Only human studies (original research) published in English were included.

Evidence Synthesis: PSMs are present in 0-7% of patients after open PN, in 0.7-4% after laparoscopic PN, and in 3.9-5.7% after robot-assisted PN. The thickness of healthy parenchyma surrounding the tumour is irrelevant as long as complete tumour removal is achieved. The coincidence of a highly malignant tumour and PSM increases the risk of local recurrence. Intermediate follow-up data indicate that the vast majority of patients with PSMs will not experience local or distant tumour recurrence. Frozen-section analysis for evaluation of resection margins during PN is of minor clinical significance, as the surgeon's gross assessment of macroscopically negative margins provides reliable results.

Conclusions: PSMs in PN are rare. As indicated by intermediate follow-up data, the majority of patients with PSMs after PN remain without disease recurrence, and a surveillance strategy seems preferable to surgical reintervention.