Melanoma nodal management in Ontario following ASCO/SSO guidelines.

e21054 Background:Methods:Results: Conclusions:The American Society of Clinical Oncology and Society of Surgical Oncology (ASCO/SSO) published a joint guideline in 2012 regarding indications for sentinel lymph node biopsy (SLNB) in cutaneous melanoma. The guideline supported completion lymph node dissection (CLND) for all patients with a positive SLNB. We examined the rates and predictors of SLNB and CLND for melanoma patients in Ontario (population 13.6 million) following guideline publication. Methods: We used the Ontario Cancer Registry (OCR) to identify cutaneous melanoma patients diagnosed in 2013. Patient records were linked to prospectively maintained health administrative databases to obtain details for each patient including surgical procedures. Results: We identified 3298 melanoma patients from Ontario in 2013 of which 1,973 (59.8%) could be analyzed. The majority, 1,227 (62.2%) had a local excision alone, while 746 (37.8%) had a SLNB. SLNB was performed on T1, T2, T3 and T4 primary melanomas in 13.9%, 67.8%, 62.6% and 47.2% of cases respectively. Receipt of a SLNB was positively associated with a younger age (< 80), higher T stage, and non-head and neck primary in multivariate analysis. Of the patients who received a SLNB 136 (18.2%) were found to be node positive. A CLND was performed in 82 (60.3%) of these patients. Conclusions: In Ontario only two-thirds of intermediate thickness melanomas (T2, T3) received a SLNB as recommended by the ASCO/SSO guidelines. Utilization was lower for head and neck patients and higher for younger (< 80 years) patients. Use of CLND for positive SLNB was also low relative to the guidelines.