CHICAGO — Radiation therapy significantly reduced the risk of recurrence in melanoma patients at high risk of relapse after lymphadenectomy, according to a phase III intergroup trial.
Among 217 fully evaluable patients, 68% of patients treated with external beam radiation after surgery had lymph node field recurrence at 2 years, compared with 80% of those observed after surgery. In an intent-to-treat analysis in 248 patients, recurrence rates were 65% vs. 82%, respectively. Median follow-up was 39 months.
Early radiotherapy toxicity appears minimal, Dr. Bryan Burmeister reported on behalf of the Trans Tasman Radiation Oncology Group 02.01/Australia and New Zealand Melanoma Trial Group 01.02 at the annual meeting of the American Society for Radiation Oncology (ASTRO).
“I believe this is the only real advance in the management of melanoma to happen in the last 15 years, since the interferon data came out,” Dr. Burmeister said in a press briefing. He urged physicians to discuss radiation therapy as an option with their melanoma patients.
Dr. Matthew Ballo, who was invited to discuss the results during the plenary presentation, said that the value of adjuvant radiotherapy in melanoma has been debated for years, and that as recently as 2004 it was viewed as a management approach of undetermined potential that should not be considered in routine practice.
“We now have high-level evidence supporting radiation therapy in selected patients with lymph node disease from malignant melanoma,” he said.
He cautioned that the lack of overall survival benefit observed in the trial may impede rapid acceptance of the data. Median survival times were 31 months with radiotherapy and 34 months with observation (P= .14). There were 120 deaths, 2 of which were not melanoma related.
Dr. Ballo suggested that radiologists in the clinical arena stress the importance of regional control, and remind colleagues in the academic arena that improvements in outcome occur in small steps. Relapse rates in patients with high-risk features, such as those in the study, are 30%–50%, he noted.
Patients were eligible if they had involvement of at least one parotid, at least two cervical or axillary, or at least three groin nodes; or extranodal spread; or a minimum metastatic node diameter of 3 cm in the neck or axilla or 4 cm in the groin. Patients randomized to radiation received 48 Gy in 20 fractions. Radiotherapy compliance was 79%.
Grade 3 toxicities 2 weeks post radiation included 18 cases of dermatitis and 2 of pain. At 6 weeks, there were five cases of dermatitis, two of pain, and one of fatigue, said Dr. Burmeister, director of radiation oncology at Princess Alexandra Hospital in Brisbane, Australia. No grade 4 early toxicities were reported.
Longer-term results are needed to assess fibrosis, lymphedema, and brachial plexopathy, as well as recurrence-related morbidity in the control arm, said Dr. Ballo, head of radiation oncology at the M.D. Anderson Clinical Care Center in Nassau Bay, Tex.
'I believe this is the only real advance in the management of melanoma to happen in the last 15 years.'
Source DR. BURMEISTER
Vitals
Major Finding: Radiation therapy after lymphadenectomy reduces melanoma recurrence in patients at high risk.
Source of Data: Phase III intergroup trial of 217 fully evaluable patients.
Disclosures: The study was supported by the Australia and New Zealand Melanoma Trial Group, National Health and Medical Research Council of Australia, and Cancer Council Victoria. Dr. Burmeister and Dr. Ballo reported no conflicts of interest.