Dr. Deborah C. Marshall recently presented her research findings on radiosurgery during the 83rd American Association of Neurological Surgeons (AANS) Annual Scientific Meeting held from May 2 to 6, 2015 in Washington, D.C. According to an AANS press release, the presentation was entitled “Survival Patterns of Patients with Cerebral Metastases after Multiple Rounds of Stereotactic Radiosurgery (SRS).” Dr. Marshall received this year’s Leksell Radiosurgery Award, an award given to the best paper on stereotactic radiosurgery (SRS) related to brain tumors.
SRS is a highly precise, non-surgical procedure of radiation therapy developed to treat small, localized brain tumors. It focuses the x-ray beams more closely to the tumor than conventional radiation therapy so it can deliver a higher, more effective dose of treatment to the tumor site while minimizing damage to the surrounding healthy tissue. SRS is often employed in cases where the risk for surgery is too high or because the tumor is in an important and delicate brain area.
SRS is an expensive procedure and with the increasing focus on cost containment, the practice of multiple SRS rounds in patients with brain metastases distant from the initial tumor site is under evaluation. The main concern is that these brain metastases or tumor recurrence can represent a poor survival prognostic.
In the study, Dr. Marshall and colleagues retrospectively evaluated the clinical outcome of 801 patients treated at the University of California, San Diego/San Diego Gamma Knife Center (UCSD/SDGKC) who had 3,683 brain metastases from primary breast, lung, melanoma, renal and colorectal cancers. The team compared patients who were submitted to a single SRS round (643 patients) and patients who underwent multiple SRS rounds (158 patients) for brain metastases.
Researchers observed that patients submitted to multiple SRS rounds tended to be younger, have systemic disease control, a lower cumulative tumor volume and an increased number of metastases. Interestingly, the team found that the median survival from the time of the final SRS round did not differ between patients submitted to one or multiple rounds.
The team concluded that additional rounds of SRS did not significantly improved the patient’s overall survival rate, and suggests that the decision of the physician between whole brain radiation therapy and multi-round SRS should be made individually according to the patient’s clinical condition.