Melanoma metastasis

Diagnosis: Melanoma metastasis

Clinical History

Changing pigmented lesion: growth, color change, asymmetry, irregular borders. Personal/family history of melanoma. History of blistering sunburns, tanning bed use. Fair skin, many nevi, dysplastic nevi.

Treatment

Wide local excision with margins based on Breslow thickness (0.5cm for in situ, 1cm for ≤1mm, 1-2cm for >1mm). SLNB for ≥0.8mm. Adjuvant immunotherapy for stage III+. Advanced: nivolumab, pembrolizumab, ipilimumab, dabrafenib+trametinib (BRAF+).

Differential Diagnosis

• Dysplastic (atypical) nevus • Seborrheic keratosis • Blue nevus • Pigmented basal cell carcinoma • Pigmented dermatofibroma • Thrombosed hemangioma • Solar lentigo

Key Learnings

• ABCDE criteria: Asymmetry, Border irregularity, Color variation, Diameter >6mm, Evolving • "Ugly duckling sign" — the lesion that looks different from the patient's other moles • Breslow thickness is the single most important prognostic factor • Sentinel lymph node biopsy recommended for lesions ≥0.8mm or with ulceration • Subtypes: superficial spreading (most common), nodular, lentigo maligna, acral lentiginous • Acral lentiginous melanoma: most common type in dark-skinned individuals — check palms, soles, nails • Hutchinson sign in subungual melanoma: pigment extending to nail fold • Immunotherapy (anti-PD-1, anti-CTLA-4) and targeted therapy (BRAF/MEK inhibitors) revolutionized treatment of advanced melanoma

Tags: Melanoma metastasis, mri