Lentigo maligna and malignant melanoma

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Lentigo maligna is a precancerous lesion often found on the face of elderly individuals.
• It presents as a brown-black, irregularly pigmented freckle.
• Malignant melanoma can develop from lentigo maligna.

Purpose of the Study:

• To review clinical and histological findings of lentigo maligna.
• To analyze the progression of lentigo maligna to malignant melanoma.
• To assess the prognostic implications of melanoma developing from lentigo maligna.

Main Methods:

• Review of clinical and histological data from 99 patients with malignant melanoma.
• Analysis of cases where lentigo maligna was the pre-existing lesion (21 patients).
• Literature review on lentigo maligna and malignant melanoma development.

Main Results:

• Lentigo maligna was the precursor lesion in 21 out of 99 malignant melanoma cases.
• Eight of these 21 patients developed metastatic disease after melanoma development.
• Prognosis for malignant melanoma appears consistent whether it arises from lentigo maligna or de novo.
• A diagnostic challenge exists during the indefinite period of melanoma development from lentigo maligna.

Conclusions:

• Malignant melanoma arising from lentigo maligna shares a similar prognosis to melanoma developing de novo.
• The indeterminate histological phase complicates accurate diagnosis and treatment outcome reporting.
• Early identification and management of lentigo maligna are crucial to potentially prevent melanoma progression.