Recurrent Central Nervous System (CNS) lesions:
Post-radiotherapy primary CNS tumor recurrences
(
38,
39) and recurrent brain metastases (
40) have been safely retreated with radiosurgery (
38,
40) or fractionated stereotactic radiotherapy (
39). In the case of recurrent gliomas, median survival extensions of 7 and 7.8 months have been reported with single fraction radiosurgery and fractionated stereotactic radiotherapy, respectively, with no significant complications, and occasional long-term survivals in patients with small volume recurrences
(
38,
39). The retreatment result has been more durable with linac-based radiosurgery for brain metastases, with an 84% rate of local control 2 years following radiosurgical retreatment (
40). In the case of metastatic lesions, the 84% 2 year local control rate and 57% overall brain disease-free rate appears to significantly exceed the result reported with standard radiotherapy retreatment (
11).
Image adapted from
"Robotic Radiosurgery" - First Edition