Timing of Definitive Surgical Management of Primary Cutaneous Melanoma: Association With Survival

INTRODUCTION: It is widely accepted that definitive surgical treatment for primary cutaneous melanoma should occur promptly, but the effects of a delay between initial diagnosis and definitive surgery remain unclear. In addition, high quality evidence is lacking for an optimal time-to-surgery from initial melanoma diagnosis. The aim of this study was to determine whether the timing of surgical treatment for Stage I & II melanoma was associated with survival outcome and whether there was an optimal time interval between melanoma diagnosis and definitive surgical treatment with respect to survival. METHODS: This was a retrospective cohort study of patients with primary cutaneous melanoma treated at a single institution between 1990 and 2015. The associations between time-to-surgery and clinical outcomes including overall survival (OS) and recurrence-free survival (RFS) were described using the Kaplan-Meier method. Multivariable Cox proportional hazard models were used to quantify the relationship between each time-to-surgery cohort and clinical outcome. RESULTS: In total 18, 242 patients were included in the analysis. Their average age was 57.5 years and 57% were male. The majority of primary melanomas were located on the trunk (32.5%) and upper limb (24.7%). Mean Breslow thickness was 1.8 mm (range 0.1-50 mm) and 64% were of superficial spreading subtype. Time to surgery was divided into ≤ 1 week, 1-4 weeks, 4-8 weeks, 8-12 weeks and > 12 weeks (n = 2453, 8882, 5906, 870 and 126, respectively). Increased delay of definitive surgical treatment was associated with poorer OS and RFS, with an OS HR of 1.23 for the 8-12 week group compared to the 1-4 week group. For RFS HR was 1.36 for the same cohorts. CONCLUSION: Definitive surgical treatment of patients with primary cutaneous melanoma between 1-4 weeks post-diagnosis with excision-biopsy was associated with improved OS & RFS compared to those treated within 1 week and greater than 4 weeks in this patient cohort treated prior to the use of adjuvant drug therapy.