Prospective study of patterns of surgical management in adults with primary cutaneous melanoma at high risk of spread, in Queensland, Australia

Background Knowledge of variation in diagnosis and surgery in high-risk primary melanoma patients is limited. We assessed frequency and determinants of diagnostic procedures, wide local excision (WLE) and sentinel lymph node biopsy (SLNB). Methods People in Queensland newly diagnosed with melanoma, clinical stage 1b or 2, were recruited prospectively. Patient information was collected from questionnaires and pathology records. Differences in surgical procedures in relation to host and tumor characteristics were assessed. Results In 787 participants, primary melanoma was diagnosed by surgical excision (74%), shave (14%), punch (12%) or incisional (1%) biopsy. General practitioners (GPs) diagnosed 80%. Diagnostic procedure differed by remoteness of residence, health sector, treating doctor's specialty and melanoma site and thickness. 766 patients had WLE, 86% by surgeons. Of 134 residual melanomas, 13 (10%) were ≤ 1 mm at diagnosis but > 1 mm at WLE, mostly after shave biopsy. SLNB was performed in 261 (33%) patients. SLNB was more common in those under 50, in remoter locations or treated by GP initially, and less common with head and neck melanoma. Conclusion Diagnostic and surgical procedures for primary melanoma vary substantially and partial biopsy can influence initial tumor microstaging. Patient, tumor and doctor characteristics influence SLNB practice.