Predictors and patterns of melanoma recurrence following a negative sentinel lymph node biopsy.

To analyse the patient demographics, tumour characteristics and follow-up data of patients with recurrence of melanoma following a negative sentinel lymph node biopsy. A retrospective review of a prospectively maintained melanoma database was conducted. Melanoma patients who had a negative sentinel lymph node were identified and we performed statistical analysis on their respective demographics, tumour histology characteristics and follow-up data. Of 164 patients studied, 40 (24%) had a recurrence of melanoma at a median of 39.5 months following diagnosis (range 1-92 months). Distant metastases were the most common form of disease recurrence (40% of all recurrences). Increasing tumour thickness was an independent predictor of recurrence on multivariate analysis while nodular histology approached significance. Median survival of 6 months was seen following disease recurrence (range 1-126 months). In the setting of a negative sentinel lymph node biopsy, there remains a risk of melanoma recurrence. Distant metastases were the most common form of recurrence. Disease recurrence occurred more frequently in those with thick primary tumours. Recurrences occurred at long intervals from diagnosis indicating the need to consider prolonged patient follow-up.