Recurrence behavior in early-stage cutaneous melanoma: pattern, timing, survival, and influencing factors.

Nearly one-third of all melanoma patients will experience disease recurrence and the majority of the relapses eventually develop metastatic disease as a consequence of disease progression in the early-stage melanoma patients. As very few number of studies have investigated the natural recurrence history of early-stage cutaneous melanoma at the first relapse, we analyzed the time until recurrence along with the patterns and outcomes of the relapses in this retrospective study. A total of 332 patients who were initially diagnosed with nonmetastatic melanoma and developed recurrence during the disease course and/or follow-up were included in the analysis. Locoregional relapse alone defined regional lymph node metastases, distant skin, subcutaneous, and satellite/in-transit metastases. Nearly half of the primary recurrences were locoregional metastasis alone (50.6%), followed by mixed locoregional and distant metastases (25.9%), and distant metastases alone (23.5%). In terms of distant metastasis, the lung was the most frequently affected site (30.7%), followed by bone (15.7%), liver (13.9%), and brain (10.8%). The time intervals for each of the recurrence patterns and distant metastasis sites were identical and nearly 16 months. Nearly two-thirds of the relapses occurred within the first 2 years of diagnosis. A significant survival advantage was observed in locoregional relapse alone compared with other relapse patterns (P<0.0001). In conclusion, about half of the melanoma patients developed locoregional relapse alone and it was found to be associated with a favorable prognosis for outcome. Because nearly two-thirds of the relapses occurred within the first 2 years of diagnosis, we suggest that all early-stage melanoma patients should be kept under a strict, thorough, and close follow-up program for at least 2 years following the diagnosis.