The Response Assessment in Neuro-Oncology for Brain Metastases (RANO-BM) criteria are the gold standard for assessing brain metastases (BMs) treatment response. However, they are limited by their reliance on one dimension, despite the routine use of high-resolution T1-weighted MRI scans for BMs, which allows for 3D measurements.

MOLAB researchers together with neuro-radiologists and neuro-oncologists from Hospital 12 de Octubre, Instituto Valenciano de Oncología, Hospital Universitario de Salamanca, Hospital de San Chinarro and Hospital Regional Universitario de Málaga developed a study to compare the performance of RANO-BM with criteria based on fractional variations of the total volumes. 

The investigators retrospectively evaluated a dataset comprising 783 BMs and analyzed the response of 185 of them from 132 patients who underwent stereotactic radiotherapy between 2007 and 2021 at the five hospitals.

The study showed that the proposed volumetric criteria outperformed the RANO-BM criteria in several aspects. First, the volumetric criteria allowed to evaluating every lesion considered in the study, while RANO-BM failed to evaluate 71.9% of them. They classified response effectively in 140 lesions, compared to only 72 lesions classified by RANO-BM. BM recurrences where identified a median of 3.3 months earlier using volumetric criteria than RANO-BM criteria. 

Thus, the study demonstrated the superiority of volumetric criteria in improving the response assessment of BMs compared to the RANO-BM criteria. The new proposed criteria allow for evaluation of every lesion, regardless of its size or shape, better classification, and enable earlier identification of recurrent lesions. Thus, volumetric criteria may provide a standardized, reliable, and objective tool for assessing treatment response.

Journals website

Paper reference:

B Ocaña-Tienda, J Pérez-Beteta, JA Romero-Rosales, B Asenjo, A Ortiz, LA Pérez Romasanta, JD Albillo, F Nagib, M Vidal Denis, B. Luque, E. Arana, VM Pérez-García. Volumetric Analysis: Rethinking Brain Metastases Response Assessment.

Neuro-Oncoloy Advances 6(1), 1-9 (2024)