Computed tomography in staging of patients with melanoma metastatic to the regional nodes

Background: This study addresses the yield and clinical impact of computed tomography (CT) imaging in otherwise asymptomatic patients with stage III melanoma metastatic to the regional nodes. Methods: The database from the University of Michigan Mutlidisciplinary Melanoma Clinic was reviewed and identified 127 asymptomatic patients with stage III melanoma (regional nodal disease) who received CT scans of the head, chest, abdomen, and/or pelvis. Scans were confirmed as true positive, false positive, and normal. Results: Four hundred twenty-six head and body CT scans were performed at the time of presentation of stage III disease. Twenty patients had a true-positive CT scan revealing unsuspected metastases. Fifteen patients had abnormal CT scans subsequently shown to be a benign process or second malignancy. The incidence of true-positive CT scans was not different between the groups of patients who had clinically apparent versus occult nodal disease. There was a significantly higher incidence of abdominal and pelvic metastatic sites identified by CT scan in patients with inguinal nodal disease compared with axillary or head and neck node-positive patients. Conclusions: The yield of detection of unsuspected metastases by CT scans in asymptomatic patients with stage III melanoma was not insignificant. Because patients with resected stage III disease are recommended to have adjuvant interferon-α for 1 year, CT staging plays an important role in identifying appropriate candidates for treatment. The toxicity of interferon-α therapy is not insignificant. The value of routine CT in asymptomatic patients with nodal metastasis deserves further prospective study.