The interval between primary melanoma excision and sentinel node biopsy is not associated with survival in sentinel node positive patients - An EORTC Melanoma Group study

Background: Worldwide, sentinel node biopsy (SNB) is the recommended staging procedure for stage I/II melanoma. Most melanoma guidelines recommend re-excision plus SNB as soon as possible after primary excision. To date, there is no evidence to support this timeframe. Aim: To determine melanoma specific survival (MSS) for time intervals between excisional biopsy and SNB in SNB positive patients. Methods: Between 1993 and 2008, 1080 patients were diagnosed with a positive SNB in nine Melanoma Group centers. We selected 1015 patients (94%) with known excisional biopsy date. Time interval was calculated from primary excision until SNB. Kaplan-Meier estimated MSS was calculated for different cutoff values. Multivariable analysis was performed to correct for known prognostic factors. Results: Median age was 51 years (Inter Quartile Range (IQR) 40-62 years), 535 (53%) were men, 603 (59%) primary tumors were located on extremities. Median Breslow thickness was 3.00 mm (IQR 1.90-4.80 mm), 442 (44%) were ulcerated. Median follow-up was 36 months (IQR 20-62 months). Median time interval was 47 days (IQR 32-63 days). Median Breslow thickness was equal for both