Patterns of Failure after Stereotactic Radiosurgery of the Resection Cavity Following Surgical Removal of Brain Metastases.
BACKGROUND
Whole brain radiation treatment (WBRT) is considered standard treatment for BM. However, exposing large volumes of normal brain tissue to irradiation can cause neurotoxicity. This study describes our experience with 100 consecutive patients with brain metastases who were managed with surgical extirpation followed by stereotactic radiosurgery (SRS) to the resection cavity.


METHODS
Patients with 1-3 brain metastases (BM), who underwent resection of 1-2 BM between June 2005 and December 2013, were treated with SRS directed to the tumor cavity and for any synchronous BM. Local and distant treatment failures were determined based on neuroimaging. Kaplan-Meier curves were generated for local and distant failure rates and overall survival.


RESULTS
One hundred and two resection cavities were treated with SRS in 100 consecutive patients. Thirty-two additional synchronous metastases were treated in 27 patients during the same session. The median overall survival was 18.9 months. Local control rate at 1 year was 84%. Longer delays between surgery and SRS were associated with increased risk of local failure (hazard ratio, -1.46; P = 0.02). Distant progression occurred in 44% of the patients at a mean of 8.8 ± 6.6 months after SRS treatment. Ten cases of leptomeningeal spread occurred around the resection cavities (9.8%). Central nervous system failure was not significantly associated with survival. Multivariate Cox regression analysis showed that recursive partitioning analysis and active systemic disease were significantly associated with survival.


CONCLUSIONS
The strategy described provides acceptable local disease control when compared with WBRT following surgery. This approach can delay and even annul WBRT in the majority of selected BM patients, especially recursive partitioning analysis class I patients. SRS should be scheduled as soon as possible after surgery.
Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel; Stereotactic Radiosurgery Unit, Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Ido
I
Strauss
Institute of Radiotherapy, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Benjamin W
BW
Corn
Department of Neurosurgery, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada.
Vibhor
V
Krishna
Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel; Stereotactic Radiosurgery Unit, Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Tal
T
Shahar
Institute of Radiotherapy, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Diana
D
Matceyevsky
Institute of Radiotherapy, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Elijahu
E
Gez
Institute of Radiotherapy, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Natan
N
Shtraus
Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel.
Zvi
Z
Ram
Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel; Stereotactic Radiosurgery Unit, Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel. Electronic address: andrewk@tlvmc.gov.il.
Andrew A
AA
Kanner
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D016634:Radiosurgery; D012189:Retrospective Studies; D017211:Treatment Failure
Brain metastases; Failure; Post-resection; Stereotactic radiosurgery