Abstract
Brain metastasis patients require granular surgical risk evaluation. The authors aimed to improve prognostication for brain metastasis patients by creating the Metastatic Brain Lesion Score (MBLS).
This is a retrospective cohort study of patients undergoing craniotomy for brain metastasis between Jan 1, 2014 and Sept 30, 2021 at a large tertiary referral center. Patients were excluded if they had craniotomy for non-metastatic lesions, radiation necrosis, or skull metastases only. The primary outcome was to define factors that predicted mortality at 90 days. Secondary measures were mFI-11 and RPA classifications. Multivariable logistic regression analyses were conducted to identify the clinically and statistically relevant predictors for the predicted mortality at 90 days with the creation cohort (n = 548). The metric developed was validated with the new data (validation cohort, n = 318), and was compared its prediction performance with secondary measures.
866 consecutive patients (n = 548 creation cohort, n = 318 validation cohort) were reviewed and analyzed. Score factors included in the MBLS were: age > 65 (OR 1.97 (95%CI 1.19-3.02)), presence of supra- and infratentorial metastases (OR 1.696 (1.04-2.78)); hemorrhagic metastasis (OR 1.699 (1.09-2.64)); chronic opiate use (OR 2.34 (1.43-3.84)); poor functional status (OR 1.90 (1.22-2.97)); and presence of deep brain/brainstem lesions (OR 2.01 (1.07-3.78)). 61/164 (37.2%) creation cohort patients and 51/116 (43.9%) validation cohort patients with MBLS score ≥ 3 were deceased at 3 months. High-risk patients in the creation cohort were significantly more likely to be deceased 3 months postoperatively (OR 3.699 (95%CI 2.41-5.682), P < 0.001). In the validation cohort, MBLS was highly predictive (OR 5.311 (95%CI 3.06-9.22), P < 0.001) with a c-statistic of 0.696.
The MBLS provides "high-risk" surgical categorization for brain metastasis patients. By using preoperative characteristics obtainable from imaging and chart review, it can be utilized in preoperative discussions, giving a clearer view of potential postoperative course and outcome.