Quantitative Analysis of the Spatial Distribution of Metastatic Brain Lesions.

Ted K Yanagihara,Tony J C Wang,Albert Lee

doi:10.18383/j.tom.2016.00268

Ted K Yanagihara, Tony J C Wang + Show 1 more

Open Access

https://doi.org/10.18383/j.tom.2016.00268

Copy DOI

Abstract

Brain metastases (BMs) are the most common intracranial malignancy and afflict ∼10%–20% of patients with cancer. BMs tend to present at the boundaries of gray and white matter because of the distribution of small vessels. In addition, metastases may not be randomly distributed across gross anatomical regions of the brain, but this has not previously been quantified. We retrospectively analyzed a series of 28 patients with recurrent BMs with a total of 150 lesions. Each lesion was manually defined based on T1 gadolinium-enhanced imaging. Standard brain atlases were used to identify the anatomical brain region affected by each BM and the frequency of metastases in each region was compared with the expected probability, which was assumed to be a random distribution based on the brain volume. After correction for multiple comparisons, the paracingulate gyrus was found to have a statistically significant increase (P = 4.731 × 10−9) in the rate of BMs relative to the random spatial distribution. A nonstochastic spatial distribution of metastases may be used to guide partial brain radiotherapy with risk-adapted dose delivery and reduce the risk of neurotoxicity due to overtreatment.

Highlights

Whole-brain radiotherapy (WBRT) for patients with brain metastases (BMs) is a commonly used technique to treat both visible and subclinical disease
Patients who have previously been treated for BMs or who are at an increased risk for developing BMs often undergo surveillance imaging with serial magnetic resonance imaging (MRI) scans, and treatment may involve focal radiotherapy, such as with stereotactic radiosurgery, or WBRT
WBRT remains the standard of care for many patients with BMs, improvements in systemic therapy have led to gains in survival for patients with metastatic disease, and the long-term neurocognitive toxicities associated with WBRT must be weighed against the benefits of treatment

Summary

Introduction

Whole-brain radiotherapy (WBRT) for patients with brain metastases (BMs) is a commonly used technique to treat both visible and subclinical disease. Accurate segmentation of the brain based on BM risk would permit the radiation dose to be spatially tailored to improve disease control in high-risk regions and spare neurotoxicity by reducing dose to low-risk regions. Patients who have previously been treated for BMs or who are at an increased risk for developing BMs often undergo surveillance imaging with serial magnetic resonance imaging (MRI) scans, and treatment may involve focal radiotherapy, such as with stereotactic radiosurgery, or WBRT. WBRT remains the standard of care for many patients with BMs, improvements in systemic therapy have led to gains in survival for patients with metastatic disease, and the long-term neurocognitive toxicities associated with WBRT must be weighed against the benefits of treatment. Several lines of investigation are directed toward mitigating long-term toxicities associated with full-dose irradiation to the entire brain

Methods

Results

Conclusion