Diagnostic accuracy of imaging studies for initial staging of T2b to T4b melanoma patients: A cross-sectional study.

BACKGROUND: There is no consensus on the imaging tests that should be performed at the initial staging of melanoma patients. OBJECTIVE: To evaluate the diagnostic accuracy of 4 imaging studies for the initial staging of melanoma patients. METHODS: Cross-sectional study with prospectively collected data, from January 2011 to April 2017, including patients with clinical stage T2b to T4b according to 2009 American Joint Committee on Cancer, without evidence of metastasis. RESULTS: Initial staging of 308 patients detected 16.6% of metastases and 5.8% false-positive results, overall. Regional lymph node ultrasonography showed a metastasis detection rate (MDR) of 12.8%, false-positive rate of 0.8%, and accuracy of 96.0%. Computed tomography (CT) and positron emission tomography-CT had the highest detection rates at stage T4b: MDR, 13.3%; false-positive rate, 8.9%; accuracy, 91.1%; and MDR, 6.9%; false-positive rate, 0%; and accuracy, 93.1%, respectively. Brain magnetic resonance imaging showed a MDR of 2.0% in T4b. LIMITATIONS: Single-center study. CONCLUSION: Performing ultrasound scans for assessing lymph node metastasis in patients with American Joint Committee on Cancer T2b stage and above is advisable. In patients with stage T4b, CT or positron emission tomography-CT are suitable for the detection of metastasis. Brain magnetic resonance imaging at T4b deserves further discussion, considering the ultimate clinical benefit in management and therapeutic options for asymptomatic patients.