Asymptomatic brain metastases in patients with cutaneous metastatic malignant melanoma

The aim of the study was to identify the frequency of asymptomatic brain metastases detected by computed tomography (CT) scans in patients with metastatic cutaneous melanoma referred to first-line systemic treatment. Between 1995 and 2009, 697 Danish patients were screened with a contrast-enhanced CT scan of the brain before the start of interleukin-2 (IL-2)-based immunotherapy. Among the 697 patients, 80 had asymptomatic brain metastases (12%). Patients' characteristics did not differ significantly between groups with and without brain metastases. Patients received systemic treatment (IL-2-based or cytotoxic chemotherapy), local treatment (stereotactic radiotherapy, whole-brain radiotherapy or surgery), or best supportive care only. The survival was significantly shorter for patients with asymptomatic brain metastases compared with patients without brain metastases (P<0.0001). The median survival was 4.5 versus 9.2 months; 1-year survival was 12.5 versus 38.4% for patients with or without asymptomatic brain metastases, respectively. We conclude that 12% of patients with metastatic cutaneous melanoma who qualified clinically for IL-2 treatment had asymptomatic brain metastases, detected by CT scans with contrast. Proper staging of metastatic cutaneous melanoma including contrast-enhanced CT of neck, thorax, and abdomen and contrast-enhanced MRI of the brain is mandatory, as systemic treatment options with comparable safety and efficacy in patients with and without brain metastases have emerged.