We have thoroughly read the study by Schwartz et al. on the impact of surgeon experience on postoperative outcomes of glioblastoma surgery in elderly patients. We agree with the authors that age is a significant risk factor for worse overall survival of glioblastoma surgery, and adjuvant therapy is crucial for postoperative survival. However, significant patient frailty, in addition to increased age, should be accounted for in the comparison of surgical brain tumor patients at high risk for post operative complications.

Huq et al. state that elderly patients tend to have increased frailty as age increases [1]. Additionally, elderly patients often require additional considerations in surgery, such as sacrificing greater extent of resection in order to decrease risk of postoperative complications and allow for adjuvant treatment [2]. However, increased age does not directly predict increased patient frailty and associated postoperative complications.

A large retrospective study examining the predictive value of the 5-factor modified frailty index (mFI-5) in 1692 patients that received primary surgery for brain tumor resection showed that an increased mFI-5 score was significantly associated with increased odds of various postoperative complications upon multivariate analysis that included adjustment for patient age. Additionally, a notable portion (19%) of the patients in this study had significant frailty (mFI-5 ≥ 2) despite the mean age of the patients in this group being only 64.1 ± 12.7 [1]. These results demonstrate that age alone is not a sufficient factor to consider in determining which patients are at high risk for poor postoperative outcomes, and it is crucial to account for frailty when including patients in this group.

We recognize the importance of the multi-center study conducted by Schwartz et al. investigating the impact of surgeon experience on outcomes of glioblastoma surgery in elderly patients since increased age can affect surgical decision making to optimize postoperative outcomes. Nonetheless, it is crucial to note there are other prognostic factors, such as those included in the mFI-5, that have been shown to predict postoperative outcomes. Comparison of patients considered high risk for postoperative complications based on age is incomplete, and frailty should be included in this comparison as it is significantly predictive of postoperative outcomes independent of patient age.