Efficacy
The role of adjuvant radiation therapy following lymphadenectomy in melanoma patients identified as at high risk for further recurrence has been controversial. A number of studies have shown the use of adjuvant radiation therapy reduces the risk of further lymph-node field relapse after lymphadenectomy in patients at high risk of relapse, although no significant effect on overall survival has been demonstrated.rrr
Burmeister et al. reported on the TROG 02.01 phase III trial which randomised 250 patients with clinically positive lymph nodes (in the head and neck, axilla and groin) deemed to be at high risk for locoregional recurrence following surgical resection to either receive radiation therapy (48Gy in 20#) (n=109) or observation (n=108).r At a median follow up of 40 months, the risk of relapse in the regional lymph nodes was significantly reduced with adjuvant RT compared to observation, 20 relapses vs 34 relapses respectively (HR 0.56, 95% CI 0.32-0.98, p=0.041). However, there were no significant differences in relapse free survival (70 vs 73 relapses, HR 0.91) or overall survival (59 vs 47 deaths, HR 1.37).
Figure 1 - Kaplan Meier curves of time to lymph-node field relapse by treatment group in the eligible population (A) and the intention to treat population (B) hazard ratios are for adjuvant radiation therapy versus observation.
© Lancet Oncol Burmeister 2012r
A update of the TROG 02.01 trial by Henderson et al. with a median follow-up of 73 months reported that the lymph node in field recurrence was reduced in the adjuvant RT (ART) arm, with 23 (21%) relapses in the ART group vs 39 (36%) in the observation group (HR=0.52 (0.31- 0.88) p=0.023).r There was no difference in overall survival (HR=1.27; 0.89-1.79, p=0.21).