Abstract
Brain metastases (BMs) are currently managed with stereotactic radiosurgery (SRS), whole brain radiotherapy (WBRT), or surgical resection. For ineligible or refractory patients, the laser interstitial thermal therapy (LITT) offers a promising alternative. There is limited consensus regarding the radiographic evolution of ablated lesions. This study aims to systematically review the literature and conduct an exploratory volumetric analysis of BMs treated with LITT.
A comprehensive literature search was performed using PubMed/Medline, Scopus, Web of Science, Cochrane (OvidSP), Embase, and Google Scholar until February 17, 2025. Eligible studies included randomized and non-randomized clinical trials, cohorts, case-control studies, case-series, and real-world studies. Volumetric data for individual lesions were extracted using WebPlotDigitizer software and temporal trends in post-LITT volume were visualized. Kaplan-Meier survival analysis, log-rank testing, and Receiver Operating Characteristics (ROC)curves were used to evaluate the association between volume changes and local progression.
Sixteen studies met inclusion criteria, encompassing 271 patients with 282 BMs. The majority were female (60.15%) with a mean age range of 51 to 65 years. Lung cancer was the most common primary source (29.08%), with lesions most frequently located in the frontal lobe (26.60%). Seven studies provided data for volumetric analysis, capturing post-LITT changes overall for several months. A ≥ 25% increase in lesion volume after 120-180 days post-LITT strongly predicted local progression (p = 0.00184). By contrast, early expansion within the first 90 days did not correlate with progression (p = 0.6321); specifically, < 25% volume increase at this interval was not associated with local progression.
LITT is an effective treatment option for patients with BMs who are refractory to conventional therapies. Our findings underscore the importance of differentiating between transient post-ablation volumetric expansion and true tumor progression. Specifically, a ≥ 25% volume increase after 120-180 days is a robust predictor of tumor recurrence, whereas early expansion within 90 days could reflect treatment-related changes.
Not applicable.