Patterns of relapse and late toxicity after resection and whole-brain radiotherapy for solitary brain metastases

Background: This retrospective analysis was performed in order to evaluate the pattern of relapse and the risk of late toxicity for solitary brain metastases treated with surgery and whole-brain radiotherapy and to correlate the results with those from radiosurgical trials. Patients and Methods: From a total of 66 patients, 52 received 10 x 3 Gy and 10 were treated with 20 x 2 Gy whole-brain radiotherapy after resection of their brain metastases. Results: The actuarial probability of relapse was 27% and 55% after 1 and 2 year(s), respectively. The local relapse rate (at the original site of resected brain metastases) was rather high for melanoma, non-breast adenocarcinoma, and squamous-cell carcinoma. No local relapse occurred in breast cancer and small-cell carcinoma. Failure elsewhere in the brain seemed to be influenced by extracranial disease activity. Size of brain metastases and total dose showed no correlation with relapse rate. Occurrence of brain relapse was not associated with a reduced survival time, because 10/15 patients who developed a relapse received salvage therapy. Of the patients, 11 had symptoms of late radiation toxicity (the actuarial probability was 42% after 2 years). Conclusions: Most results of surgical and radiosurgical studies are comparable to ours. Several randomized trials investigate surgical resection versus radiosurgery, as well as the effects of additional whole-brain radiotherapy in order to define the treatment of choice. Some data support the adjuvant application of 10 x 3 Gy over 2 weeks as a reasonable compromise when local control, toxicity, and treatment time have to be considered.