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 = 47 days interval: 3.00 mm (1.90-5.00 mm) vs 3.00 mm (1.90-4.43 nom) (p = 0.402). Sentinel node tumor burden was significantly higher in patients operated >= 47 days (p = 0.005). Univariate survival was not significantly different for median time interval. Multivariable analysis confirmed that time interval was no independent prognostic factor for MSS. Conclusions: Time interval from primary melanoma excision until SNB was no prognostic factor for MSS in this SNB positive cohort. This information can be used to counsel patients. (C) 2016 Elsevier Ltd and British Association of Surgical Oncology/European Society of Surgical Oncology. All rights reserved