Abstract
Introduction Stage III melanoma is associated with poor outcomes. We studied the characteristics and outcomes of patients with resected Stage III melanoma before the routine use of adjuvant immunotherapy. Some of these patients received adjuvant nodal radiation with modern radiation techniques. Methods We retrieved data of patients with resected Stage III melanoma treated in Christchurch over 10 years. Overall survival (OS), melanoma-specific survival (MSS), recurrence-free survival (RFS) and nodal recurrence-free rate (NRFR) were determined, and the association of these outcomes with tumour and treatment factors was investigated. Results We identified 178 patients (110 male and 68 female), of whom 61 received adjuvant radiation. The median age was 66.6 years, and the median follow-up was 2.7 years. First recurrences occurred in 108 (61%) patients. There were 42 (24%) nodal field relapses and 103 (58%) distant relapses. One-half of nodal relapses in patients treated with adjuvant radiation were infield. The 5-year OS, RFS, MSS and NRFR were 46.4%, 26.8%, 53.7% and 69.6%, respectively. Adjuvant radiation was associated with improved RFS and no OS benefit. T4 disease and extranodal spread were associated with poorer OS, while extranodal spread and >3 involved nodes were associated with worse RFS. Conclusion Patients treated with adjuvant radiation remain at moderate risk of regional and high risk of distant relapse, despite the use of modern radiation techniques. Adjuvant radiation was associated with improved local control but infield recurrence rates remained a problem. The role of combined adjuvant radiation and immunotherapy in improving these outcomes requires further investigation.