Melanoma

Regarding imaging of melanoma,

1. Majority of the melanoma metastasis to brain are hyperdense on unenhanced CT scan
2. Melanoma metastasis in brain usually show high signal on both T1 and T2
3. Most of the intraocular melanomas are metastatic
4. Lung metastasis is relatively common
5. Most of the bone metastasis are osteolytic

Answers: T, F, F, T, T

Notes: Most of the melanoma metastasis to brain are multiple, occur at corticomedullary junction and 85% are hyperdense on unenhanced CT scan. Hemorrhage is found in nearly 20%. On MR, they are typically high signal on T1 and low on T2. Most of the intraocular melanomas are primary and ultrasound and MRI are used in the evaluation of the lesion. 40% of lung metastasis are multiple, 20% solitory, 7% adenopathy and 28% combination of these. Bone metastasis is also relatively common and seen in 23% of ocular melanomas. The most common site is spine and most are lytic.

Reference: Kalkman E et al. Melanoma. Clin Rad 59 (2004): 313-326