학술논문

Prediction of new brain metastases after radiosurgery: validation and analysis of performance of a multi-institutional nomogram
Document Type
article
Source
Journal of Neuro-Oncology. 135(2)
Subject
Biomedical and Clinical Sciences
Oncology and Carcinogenesis
Brain Neoplasms
Female
Follow-Up Studies
Humans
Male
Middle Aged
Neoplasm Recurrence
Local
Nomograms
Radiosurgery
Retrospective Studies
Risk Factors
Survival Analysis
Brain metastases
Distant brain failure
Stereotactic radiosurgery
Multi-Institutional nomogram
Neurosciences
Oncology & Carcinogenesis
Oncology and carcinogenesis
Language
Abstract
Stereotactic radiosurgery (SRS) without whole brain radiotherapy (WBRT) for brain metastases can avoid WBRT toxicities, but with risk of subsequent distant brain failure (DBF). Sole use of number of metastases to triage patients may be an unrefined method. Data on 1354 patients treated with SRS monotherapy from 2000 to 2013 for new brain metastases was collected across eight academic centers. The cohort was divided into training and validation datasets and a prognostic model was developed for time to DBF. We then evaluated the discrimination and calibration of the model within the validation dataset, and confirmed its performance with an independent contemporary cohort. Number of metastases (≥8, HR 3.53 p = 0.0001), minimum margin dose (HR 1.07 p = 0.0033), and melanoma histology (HR 1.45, p = 0.0187) were associated with DBF. A prognostic index derived from the training dataset exhibited ability to discriminate patients' DBF risk within the validation dataset (c-index = 0.631) and Heller's explained relative risk (HERR) = 0.173 (SE = 0.048). Absolute number of metastases was evaluated for its ability to predict DBF in the derivation and validation datasets, and was inferior to the nomogram. A nomogram high-risk threshold yielding a 2.1-fold increased need for early WBRT was identified. Nomogram values also correlated to number of brain metastases at time of failure (r = 0.38, p