Sentinel node biopsy status is strongly predictive of survival in cutaneous melanoma: Extended follow-up of Oxford patients from 1998 to 2014

Abstract

Introduction Sentinel lymph node biopsy (SLNB) is widely used as a key investigatory tool for cutaneous melanoma, with results incorporated into the latest AJCC staging guidelines. We present the results of our extended follow-up of sentinel lymph node biopsy for melanoma over a sixteen-year period. Methods Data were collected prospectively from June 1998 to December 2014 from a single tertiary skin cancer referral centre. Chi-squared analysis was used to analyse patient demographics and primary tumour pathology. Survival analysis was conducted using Cox regression models and Kaplan–Meier survival curves. Results Over a sixteen-year period 1527 patients underwent SLNB in 1609 basins, with 2876 nodes harvested. 347 patients (23%) had a positive biopsy. The most common primary tumour sites for males was the back (32%); women had a significantly higher number of melanomas occurring on the lower and upper limbs (45% and 26% respectively) [all p < 0.0001, Chi-squared]. Mean follow-up time was 4.9 years. Patients with a positive SLNB at diagnosis were significantly more likely to die from melanoma (subhazard ratio 5.59, p = 0.000, 95% CI 3.59–8.69). Breslow thickness and ulceration were also significant predictors of melanoma-specific mortality. For patients with a primary Breslow >4.0 mm ten-year disease free survival was 52% for SLNB negative and 26% for SLNB positive patients. For Breslow thicknesses of 2.01–4 mm these values were 66% and 32% respectively. Conclusions Sentinel lymph node biopsy status is strongly predictive of survival across all thicknesses of primary cutaneous melanoma.