Аннотация:Brain metastases (BM) are the most frequent tumorsof the central nervous system. Nowadays stereotacticradiosurgery (SRS) is treatment of choice for BM inmany situations. Local recurrences after radiosurgeryseriously complicate the course of cancer diseases andworse the prognosis of life duration, neurological statusand quality of life in patients with BM. Currently, thereare no standards of treatment for recurrent BM.The purpose of the study to evaluate the efficacyand safety of repeated radiosurgical (rRS) proceduresfor local relapses (LR) in patients with brain metastasesafter prior stereotaxic surgery.Materials and methods: An analysis of the reirradiationlocal treatment of 59 patients were carriedout. There were 110 lesions of LR detected after thepreviously performed SRS with Gamma Knife (GK).Primary cancer was: non-small cell lung cancer in 10(17%), breast cancer in 29 (49%), melanoma in 13(22%), renal cell carcinoma in 5 (8.5%) and colorectalcancer in 2 (3.5%) patients. All patients underwentrepeated radiosurgery with median marginal dose 22Gy (15 to 24 Gy).Results The local control of repeated irradiated BMfor the 6- and 12-month periods was 95.5% and83.9%, respectively. Statistically significant predictionfactors for lower risk of LR after rRS were: the volumeof the lesion ≤1 cc (p=0.0241) and dose >20Gy/D99% (p=0,031), according to multifactorial analysis.The frequency of local radionecrosis after repeatedradiosurgery was higher than after first SRS: 28.2%vs. 13.3%. The volume of LR ≤1 cc was a significantpredictor of lower risk of post-radiation edema(p=0.01) and radio necrosis (p=0.0224) according tomultifactorial analysis.Conclusions: The SRS of LR is an effective treatmentfor controlling tumor growth of repeated irradiatedBM with acceptable post-radiation toxicity. Repeatedstereotactic radiosurgery (SRS) of local recurrences(LR) of GM is designed to improve treatment outcomes,maintain quality of life and prolong it in patients withbrain metastases who relapse after prior radiosurgery.The volume of the LR focus can change the treatmenttactics: it is possible that with a metastasis recurrencesize of more than 1 cm3, it is preferable to usesurgical treatment or stereotactic radiation in thehypofractionation mode, which needs to be confirmedin further studies.
