Adjuvant nodal radiation therapy for malignant melanoma with single region nodal metastasis

• DOI: 10.1007/s13566-012-0063-6
• Publication Date: 2012-08-28T17:48:31Z
• Authors: Jennifer Sherriff; Agustin Martin-Cl...; Peter Nightingale; Anjali Zarkar
• Keywords: Surgical oncology; Adjuvant Therapy

Adjuvant radiation therapy (RT) is increasingly used following lymph node block dissection for regional recurrence/metastasis of malignant melanoma. The purpose of this retrospective study is to document the prognostic factors including different radiotherapy techniques in predicting outcome after lymph node block dissection and adjuvant RT in malignant melanoma patients with lymph node metastasis to a single nodal region. Patients receiving adjuvant radiotherapy following nodal block dissection between 1999 and 2011 were identified. The radiotherapy techniques used were reviewed. Outcome data collected for each technique identified included the rate of local recurrence, the site of local recurrence and the time to local recurrence. Progression-free and overall survival rates were calculated. Forty-nine patients were identified. Seventeen were planned with conventional simulation and 32 with CT-planned radiotherapy either using virtual simulation or a planned volume technique. The majority of patients received either 50 or 48 Gy in 20 fractions over 4 weeks for disease with a high risk of post-operative local recurrence. The median follow-up was 35 (range 3–140) months in surviving patients. Local recurrence occurred in five (29.4 %), four (25.0 %) and two (12.5 %) of those treated with simulated, virtually simulated and conformal techniques, respectively. The median overall survival for all patients was 38.3 months, and the median progression-free survival was 26.6 months. Univariable analyses revealed that metastasis to 4 or more regional lymph node was a significant predictive factor for local recurrence (p = 0.004). Presence of extracapsular extension, involved or close margins or size of the largest nodes were not significant in predicting local recurrence. Although the difference between the local control rates did not reach statistical significance with the different radiation techniques, local control is maintained using conformal radiotherapy. As metastases to 4 or more regional lymph nodes were significantly associated with reduced control, improved strategy and techniques in radiation therapy to further improve local control are needed and require further investigation.