Incomplete Excision Rate for Lentigo Maligna and Associated Risk Factors

Area of Science:

• Dermatology
• Surgical Oncology
• Pathology

Background:

• Standard treatment for lentigo maligna (LM) is surgical excision.
• Limited data exists on the frequency and risk factors for incomplete LM excisions.

Purpose of the Study:

• To determine the incomplete excision rate (IER) in primary LM.
• To identify risk factors associated with incomplete LM excisions.

Main Methods:

• Retrospective analysis of 395 histopathologically confirmed LMs (2014-2020).
• Descriptive statistics for LM characteristics and IER.
• Univariate and multivariate analyses to identify risk factors.

Main Results:

• The overall IER was 16.7%.
• Risk factors for incomplete excision included head and neck lesions (p=0.0014), clinical margins <5 mm (p=0.040), and preoperative biopsies (p=0.023).
• Plastic surgeons had higher IERs than dermatologists (p=0.036). LMs ≥20 mm had higher IERs (23.2%) than those <10 mm (12.9%).

Conclusions:

• LM excision requires careful planning, especially for head and neck lesions.
• At least 5-mm clinical margins are recommended.
• Larger lesions (≥20 mm), preoperative biopsies, and plastic surgeon involvement may indicate increased surgical complexity.