Purpose: Pathologic stage II melanoma patients have variable outcomes when divided by substage. We hypothesized that an understanding of the patterns of initial relapse by substage will better inform follow-up guidelines.
Methods: We performed a retrospective review of 738 adult patients with pathologic stage II cutaneous melanoma treated at Memorial Sloan Kettering Cancer Center between 1993 and 2013. Clinical records were reviewed to determine time, location, and method of detection of initial relapse.
Results: At a median follow-up of 52 months, 219 patients relapsed. Relapses were detected more frequently in higher substages. Initial relapses were most commonly local/in-transit for IIA and IIB and systemic for IIC. Lung and brain were the most frequent sites of systemic relapse. Patient-detection was the most common method of relapse detection (59%) in all substages. The 5-year cumulative incidence for patient-detected relapse was 13.6% for IIA, 18.9% for IIB, and 23.3% for IIC and for image-detected relapse was 3.4, 7.9, and 16.6%, respectively. The 5-year cumulative incidence for physician-detected relapse was less than 10% across all substages and leveled off at 3 years for stage IIA and IIB and 2 years for stage IIC.
Conclusions: Relapses were most frequently patient-detected in all stage II substages, highlighting the importance of patient education and self-examination. The highest yield for routine imaging is in stage IIC patients during the first 4 years. Physician examination is unlikely to detect relapses beyond 3 years for stage IIA and IIB and beyond 2 years for stage IIC patients.