AUTHOR=Aftahy Amir Kaywan , Barz Melanie , Lange Nicole , Baumgart Lea , Thunstedt Cem , Eller Mario Antonio , Wiestler Benedikt , Bernhardt Denise , Combs Stephanie E. , Jost Philipp J. , Delbridge Claire , Liesche-Starnecker Friederike , Meyer Bernhard , Gempt Jens 

TITLE=The Impact of Postoperative Tumor Burden on Patients With Brain Metastases

JOURNAL=Frontiers in Oncology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.869764

DOI=10.3389/fonc.2022.869764

ISSN=2234-943X

ABSTRACT=<sec><title>Background</title><p>Brain metastases were considered to be well-defined lesions, but recent research points to infiltrating behavior. Impact of postoperative residual tumor burden (RTB) and extent of resection are still not defined enough.</p></sec><sec><title>Patients and Methods</title><p>Adult patients with surgery of brain metastases between April 2007 and January 2020 were analyzed. Early postoperative MRI (&lt;72 h) was used to segment RTB. Survival analysis was performed and cutoff values for RTB were revealed. Separate (subgroup) analyses regarding postoperative radiotherapy, age, and histopathological entities were performed.</p></sec><sec><title>Results</title><p>A total of 704 patients were included. Complete cytoreduction was achieved in 487/704 (69.2%) patients, median preoperative tumor burden was 12.4 cm<sup>3</sup> (IQR 5.2–25.8 cm<sup>3</sup>), median RTB was 0.14 cm<sup>3</sup> (IQR 0.0–2.05 cm<sup>3</sup>), and median postoperative tumor volume of the targeted BM was 0.0 cm<sup>3</sup> (IQR 0.0–0.1 cm<sup>3</sup>). Median overall survival was 6 months (IQR 2–18). In multivariate analysis, preoperative KPSS (HR 0.981982, 95% CI, 0.9761–0.9873, <italic>p</italic> &lt; 0.001), age (HR 1.012363; 95% CI, 1.0043–1.0205, <italic>p</italic> = 0.0026), and preoperative (HR 1.004906; 95% CI, 1.0003–1.0095, <italic>p</italic> = 0.00362) and postoperative tumor burden (HR 1.017983; 95% CI; 1.0058–1.0303, <italic>p</italic> = 0.0036) were significant. Maximally selected log rank statistics showed a significant cutoff for RTB of 1.78 cm<sup>3</sup> (<italic>p</italic> = 0.0022) for all and 0.28 cm<sup>3</sup> (<italic>p</italic> = 0.0047) for targeted metastasis and cutoff for the age of 67 years (<italic>p</italic> &lt; 0.001). (Stereotactic) Radiotherapy had a significant impact on survival (<italic>p</italic> &lt; 0.001).</p></sec><sec><title>Conclusions</title><p>RTB is a strong predictor for survival. Maximal cytoreduction, as confirmed by postoperative MRI, should be achieved whenever possible, regardless of type of postoperative radiotherapy.</p></sec>