Loading...
Minimal nodal disease is associated with minimal risk. The clinical implications of minimal nodal disease in the context of sentinel lymph node (SLN) sampling remain controversial. Is completion lymph node dissection (CLND) always required, and is prognosis different if only scattered cells are found in the SN? These questions were recently addressed in a European Organisation for Research and Treatment of Cancer (EORTC) observational study.
Between 1993 and 2008, 1080 patients (571 men) were diagnosed with positive SLNs, and 1009 patients (93%) underwent CLND. Mean and median Breslow thicknesses were 4.00 mm and 3.00 mm (range, 0.1 to 90 mm), respectively. The mean and median follow-up times were 46 and 37 months (range, 1 to 172 months), and the mean and median times to first recurrence were 38 and 27 months. At last follow-up, 336 (31%) patients had died. The SLNs were then reclassified by size (Rotterdam criteria), location within the lymph node (Dewar criteria), or a combination classification (Rotterdam-Dewar Combined criteria [RDC]).
Of patients who underwent a CLND, 212 (21%) had one or more positive nonsentinel lymph nodes (NSNs). Classified according to the RDC criteria, the subgroup with minimal metastases (<0.1 mm) in the subcapsular area had the lowest rate of NSN positivity: Positive NSNs were present in only 2% of patients in this subgroup. The melanoma-specific survival of these patients was 95% at 5 and 10 years. Outcomes worsened with increasing tumor burden in the SN and also with a location other than subcapsular. The authors suggest that for patients with <0.1 mm/subcapsular disease, no CLND is needed, as the NSN rate is only 2% and the overall survival approaches that of SLN biopsy–negative patients.
van der Ploeg APT et al. Prognosis in patients with sentinel node–positive melanoma is accurately defined by the Combined Rotterdam Tumor Load and Dewar Topography Criteria. J Clin Oncol 2011 Jun 1; 29:2206.
Comment
Because completion lymph node dissection often involves considerable morbidity, the ability to spare low-risk sentinel lymph node–positive patients a second procedure is welcome. This study builds upon previous findings of nodal tumor burden as a significant prognostic factor. However, this was a retrospective, reclassification study, not a prospective trial. Follow-up was short, and a case could be made that distant metastases may take longer to manifest in patients with limited nodal disease, as is the case with thickness of primary tumors. The ongoing MSLT-II trial directly addresses this issue, and unless it proves otherwise, I would still recommend CLND in all patients with positive sentinel lymph nodes.