Is there increased risk of local and in-transit recurrence following sentinel lymph node biopsy?

Recent publications have suggested that sentinel lymph node biopsy (SLNB) and completion lymphadenectomy (CLND) increase the rate of local and in-transit disease up to 23% in sentinel node positive group of patients with cutaneous melanoma. This retrospective study combined the data from two national centres on local and in-transit disease in 972 melanoma patients who underwent SLNB procedure over 6.5 years period. In total, 77 patients (7.9%) developed loco-regional recurrence: 41 (4.2%) local recurrence only and 36 patients (3.7%) in-transit metastases during a mean follow-up of 42 months. Patients with positive sentinel lymph node were three times more likely to develop loco-regional metastases than those with no nodal disease (17 vs. 5.6%). Over one third of all recurrences developed following excision of thick (Breslow thickness over 4mm) primary tumours. In both centres age and Breslow thickness were found to be significantly higher in the recurrence group (p<0.001 for both). This study revealed a strong association between increased risk of loco-regional metastases and aggressive tumour biology and adverse patients factors. No conclusive evidence was found to support an increased incidence in patients undergoing SLNB and CLND compared to that published for patients undergoing wide local excision alone.