Does waiting for surgery matter? How time from diagnostic MRI to resection affects outcomes in newly diagnosed glioblastoma

J Neurosurg 140:80–93, 2024

Maximal safe resection is the standard of care for patients presenting with lesions concerning for glioblastoma (GBM) on magnetic resonance imaging (MRI). Currently, there is no consensus on surgical urgency for patients with an excellent performance status, which complicates patient counseling and may increase patient anxiety. This study aims to assess the impact of time to surgery (TTS) on clinical and survival outcomes in patients with GBM.

METHODS This is a retrospective study of 145 consecutive patients with newly diagnosed IDH–wild-type GBM who underwent initial resection at the University of California, San Francisco, between 2014 and 2016. Patients were grouped according to the time from diagnostic MRI to surgery (i.e., TTS): ≤ 7, > 7–21, and > 21 days. Contrast-enhancing tumor volumes (CETVs) were measured using software. Initial CETV (CETV1) and preoperative CETV (CETV2) were used to evaluate tumor growth represented as percent change (ΔCETV) and specific growth rate (SPGR; % growth/day). Overall survival (OS) and progression-free survival (PFS) were measured from the date of resection and were analyzed using the Kaplan-Meier method and Cox regression analyses.

RESULTS Of the 145 patients (median TTS 10 days), 56 (39%), 53 (37%), and 36 (25%) underwent surgery ≤ 7, > 7–21, and > 21 days from initial imaging, respectively. Median OS and PFS among the study cohort were 15.5 and 10.3 months, respectively, and did not differ among the TTS groups (p = 0.81 and 0.17, respectively). Median CETV1 was 35.9, 15.7, and 10.2 cm 3 across the TTS groups, respectively (p < 0.001). Preoperative biopsy and presenting to an outside hospital emergency department were associated with an average 12.79-day increase and 9.09-day decrease in TTS, respectively. Distance from the treating facility (median 57.19 miles) did not affect TTS. In the growth cohort, TTS was associated with an average 2.21% increase in ΔCETV per day; however, there was no effect of TTS on SPGR, Karnofsky Performance Status (KPS), postoperative deficits, survival, discharge location, or hospital length of stay. Subgroup analyses did not identify any high-risk groups for which a shorter TTS may be beneficial.

CONCLUSIONS An increased TTS for patients with imaging concerning for GBM did not impact clinical outcomes, and while there was a significant association with ΔCETV, SPGR remained unaffected. However, SPGR was associated with a worse preoperative KPS, which highlights the importance of tumor growth speed over TTS. Therefore, while it is ill advised to wait an unnecessarily long time after initial imaging studies, these patients do not require urgent/emergency surgery and can seek tertiary care opinions and/or arrange for additional preoperative support/resources. Future studies are needed to explore subgroups for whom TTS may impact clinical outcomes.

Pineal cyst: results of long-term MRI surveillance and analysis of growth and shrinkage rates

J Neurosurg 138:113–119, 2023

OBJECTIVE Pineal cyst (PC) is a relatively common true cyst in the pineal gland. Its long-term natural course remains ill defined. This study aims to evaluate the long-term natural history of PC and examine MRI risk factors for cyst growth and shrinkage to help better define which patients might benefit from surgical intervention.

METHODS The records and MRI of 409 consecutive patients with PC were retrospectively examined (nonsurgical cohort). Cyst growth and shrinkage were defined as a ≥ 2-mm increase and decrease in cyst diameter in any direction, respectively. In addition to size, MRI signal intensity ratios were analyzed.

RESULTS The median radiological follow-up period was 10.7 years (interquartile range [IQR] 6.4–14.3 years). The median change in maximal diameter was −0.6 mm (IQR −1.5 to 1.3 mm). During the observation period, cyst growth was confirmed in 21 patients (5.1%). Multivariate logistic regression analysis revealed that only age (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.93–0.99, p < 0.01) was significantly associated with cyst growth. No patient required resection during the observation period. Cyst shrinkage was confirmed in 57 patients (13.9%). Multivariate analysis revealed that maximal diameter (OR 1.22, 95% CI 1.12–1.35, p < 0.01) and cyst CSF T2 signal intensity ratio (OR 9.06, 95% CI 1.38–6.62 × 101, p = 0.02) were significantly associated with cyst shrinkage.

CONCLUSIONS Only 5% of PCs, mainly in patients younger than 50 years of age, have the potential to grow, while cyst shrinkage is more likely to occur across all age groups. Younger age is associated with cyst growth, while larger diameter and higher signal intensity on T2-weighted imaging are associated with shrinkage. Surgery is rarely needed for PCs, despite the possibility of a certain degree of growth.

Decision Making in theWait-and-Scan Approach for Vestibular Schwannomas: Is There a Price to Pay in Terms of Hearing, Facial Nerve, and Overall Outcomes?

Neurosurgery 83:858–870, 2018

The wait-and-scan modality has emerged as an important strategy in the management of vestibular schwannoma (VS) as it has been demonstrated that many tumors grow slowly or do not show any growth over long periods.

OBJECTIVE: To analyze long-term outcomes of wait-and-scan in the treatment of patients with VS, discuss the factors contributing to the decision making, determine the inherent risks of the policy, and compare our results with literature.

METHODS: In total, 576 patients with sporadic unilateral VS who were managed with wait-and-scan were reviewed retrospectively. Of these, a subset of 154 patients with 5-yr follow-up was separately analyzed. The tumor characteristics including patterns of growth, rate of growth, hearing outcomes, and likely factors affecting the above parameters were analyzed.

RESULTS: The mean period of follow-up was 36.9 ± 30.2 mo. The mean age was 59.2 ± 11.6 yr. Thirteen different patterns of tumor growth were observed. Eighty-four (54.5%) of 154 tumors with 5-yr follow-up showed no growth throughout 5 yr. Fifty-six (36.4%) tumors showedmixed growth rates. Only 57 (37%) patients had serviceable hearing at the start of follow-up, but 32 (56.1%) maintained it at the end of follow-up. One hundred fifty (26%) of the 576 patients who failed wait-and-scan had to be taken up for surgery.

CONCLUSION: While there may be no price to pay in wait-and-scan as far as hearing is concerned, this may not be the case for facial nerve outcomes, wherein the results may be better if the patients are taken earlier for surgery.