Lentigo Maligna Treated With Microscopically Controlled Surgery: A 194-Patient Retrospective Study

Area of Science:

• Dermatology and Surgical Oncology
• Cutaneous Oncology
• Surgical Pathology

Background:

• Further research is needed to establish the clinical significance of paraffin-embedded microscopically controlled surgery (MCS) for lentigo maligna (LM) and lentigo maligna melanoma (LMM).
• Accurate margin assessment is crucial for effective treatment and minimizing recurrence of these melanocytic neoplasms.

Purpose of the Study:

• To evaluate the efficacy of paraffin-embedded MCS in achieving negative margins and its association with local recurrence rates in patients with LM and LMM.
• To assess the clinical value of staged excision using paraffin-embedded MCS for LM and LMM.

Main Methods:

• Retrospective observational study of histologically confirmed LM and LMM cases treated exclusively with paraffin-embedded MCS (staged excision).
• Inclusion criteria required definitive treatment and a minimum follow-up of 6 months for recurrence-free cases.
• Data collected included patient demographics, tumor characteristics, surgical margins, and local recurrence (LR) rates.

Main Results:

• 194 patients were included, with a median age of 72.5 years; most were primary tumors (82%) located on the face.
• All patients achieved negative margins with paraffin-embedded MCS.
• A low local recurrence (LR) rate of 3.6% (7/194) was observed over a median follow-up of 34 months, with a trend towards higher LR in LMM (7.5%) versus LM (2.1%).

Conclusions:

• Paraffin-embedded MCS provides reliable margin control for LM and LMM.
• The technique is associated with a low local recurrence rate, indicating its clinical value in managing these conditions.
• Staged excision using paraffin-embedded MCS is an effective treatment modality for lentigo maligna and lentigo maligna melanoma.