Objective: To ascertain and clarify the effectiveness and advantages of the geometric staged excision technique for the removal of lentigo maligna (LM) and lentigo maligna melanoma (LMM).
Design: This was a retrospective review of a patient database composed of 293 cases of LM and LMM.
Setting: The Laser and Dermatologic Surgery Center in St Louis, Missouri, an academic-affiliated, private dermatologic surgery center.
Patients: All patients with a diagnosis of LM and LMM treated by staged excision from 1999 to 2007.
Main outcome measures: The overall rate of recrudescence, margins required for clearance, stages required for clearance, and lesional characteristics were examined.
Results: The rate of recrudescence after geometric staged excision was 1.7% (4/239), with a mean of 32.3 months of follow-up. The mean margin to clearance after excision was 6.6 mm for LM and 8.2 mm for LMM. A total of 11.7% of LMM was initially diagnosed as LM on biopsy, with the invasive component discovered during the excision.
Conclusions: Geometric staged excision is an optimal method of removal of LM and LMM given its low rate of recrudescence and ability for complete examination of the peripheral and deep margins of the specimens.