95. Imaging Findings in Melanoma

Cutaneous melanoma, the most serious type of skin cancer, may spread almost to any organ of the body. Early detection and accurate staging are of critical value for the appropriate treatment and patient’s prognosis. Imaging modalities as ultrasound, computed tomography, magnetic tomography, lymphoscintigraphy, bone scan, and PET-CT play an essential role in staging of patients with melanoma. Computed tomography (CT) is the method of choice for staging of patients with melanoma, especially in TNM stage III or in recurrence of the disease. Ultrasound (US) has not been widely used and may have a complementary role in selected cases. Magnetic resonance imaging (MRI) is superior compared to CT for the evaluation of the brain, the spinal canal, the musculoskeletal system, and the parenchymatous abdominal organs. Lymphoscintigraphy and sentinel lymph node (SLN) biopsy are indicated for the initial staging of clinically node-negative cases of melanoma and also for the patients being at risk for regional node spread. SLN biopsy is recommended for stage IA disease with adverse histological characteristics, stage IB and stage II disease. PET-CT has turned out to be more accurate than CT in N and in M initial staging and can replace conventional imaging in stage III and IV metastatic melanoma.