JAMA Oncol: Comparison of the advantages and disadvantages of whole brain radiotherapy or stereotactic radiotherapy for brain metastases

The long-term outcomes of radiation therapy are critical
to understanding the risks and benefits of treatment for patients with brain metastases.
The study aimed to clarify the association
between postoperative whole-brain radiotherapy (WBRT) or stereotactic radiotherapy (SRS) and quality of life (QOL), cognitive function, and intracranial tumor control in long-term survivors of 1-4 brain metastases.

This is a secondary analysis of a randomized phase 3 clinical trial that recruited adult patients with 1-4 brain metastases from 48 institutions in the United States and Canada, allowing one brain metastases to be removed and unremoved brain metastases to be treated
with SRS.
Primary endpoints were intracranial tumor control rate, toxicity, cognitive deterioration, and QOL.

A total of 54 patients (65% women) were included in this analysis, with a median follow-up of 23.
8 months
.
Patients treated with SRS had lower rates of cognitive deterioration at all time points (37 to 60 versus 75 to 91 percent)
compared with those receiving WBRT.
At months 3, 6, and 9, patients receiving WBRT decreased by 2 or more standard deviations (70 versus 22 percent, 46 versus 19 percent, and 50 versus 20 percent)
on one or more cognitive tests compared with SRS.
A 2 standard deviation decrease in at least 2 cognitive tests was associated with
poorer 12-month emotional well-being, functional well-being, general/additional worry, and overall scores.
At 12 months, the total control rate of intracranial tumors was 40.
7% in the SRS alone group and 81.
5% in the WBRT group (poor: -40.
7%)
.

Overall, stereotactic radiotherapy alone reduces cognitive decline
in long-term survivors of malignancy with brain metastases compared with whole-brain radiotherapy.
The association between advanced cognitive decline and whole-brain radiotherapy is clinically significant
.
Significant cognitive decline (2SD) is associated
with overall quality of life.
However, whole-brain radiation therapy improves control of
intracranial tumors.

Original source:

Palmer JD, Klamer BG, Ballman KV, et al.
Association of Long-term Outcomes With Stereotactic Radiosurgery vs Whole-Brain Radiotherapy for Resected Brain Metastasis: A Secondary Analysis of The N107C/CEC.
3 (Alliance for Clinical Trials in Oncology/Canadian Cancer Trials Group) Randomized Clinical Trial.
JAMA Oncol.
Published online October 20, 2022.
doi:10.
1001/jamaoncol.
2022.
5049