MELANOMA METASTASES TO THE NECK NODES: ROLE OF ADJUVANT IRRADIATION

Purpose: To review experiences in the treatment of regionally advanced melanoma to the neck and/or parotid with emphasis on the role of adjuvant radiotherapy. Patients and Methods: Clinical and histopathologic data, treatment details, and outcomes in patients treated during the period 2000-2006 at the Institute of Oncology, Ljubljana, Slovenia, were reviewed. Results: A total of 40 patients with 42 dissections underwent surgery, and 43 patients with 45 dissections received irradiation postoperatively to a median equivalent dose (eqTD(2): 2 Gy/fraction, 1 fraction/day, 5 fractions/week) of 60 Gy (range, 47.8-78.8). Regional control 2 years after surgery was 56% (95% confidence interval [CI] 40-72%) and after postoperative radiotherapy 78% (CI 63-92%) (p = 0.015). On multivariate analysis, postoperative radiotherapy (yes vs. no: hazard ratio [HR] 6.3, CI 2.0-20.6) and sum of the risk factors present (i.e., risk factor score; HR 1.7 per score point, CI 1.2-2.6) were predictive for regional control. On logistic regression testing, the number of involved nodes was associated with the probability of distant metastases (p = 0.021). The incidence of late toxicity did not correlate with the mode of therapy, eqTD(2), or fractionation pattern. Conclusions: Adjuvant radiotherapy has the potential to compensate effectively for the negative impact of adverse histopatologic features to disease control in a dissected nodal basin. More conventionally fractionated radiotherapy regimens using fraction doses of 2-2.5 Gy, with cumulative eqTD(2)>= 60 Gy, are recommended. The number of involved lymph nodes is proposed as an additional criterion for limiting the implementation of adjuvant irradiation. (C) 2010 Elsevier Inc.