The impact of the time to start radiation therapy on overall survival in newly diagnosed glioblastoma

Timing of radiotherapy in glioblastoma based on IMRT and STUPP chemo-radiation: may be no need to rush

OBJECTIVE

To investigate the effect of surgery to radiotherapy interval (SRI) on the prognosis of patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma.

METHODS

Retrospective analysis of the relationship between SRI and prognosis of patients with IDH wild-type glioblastoma who received postoperative intensity modulated radiotherapy (IMRT) in our center from July 2013 to July 2019. The patients were divided into SRI ≤ 42 days (regular group) and SRI > 42 days (delay group). Kaplan-Meier univariate analysis and Cox proportional hazard model were used to analyze whether SRI was an independent factor influencing the prognosis.

RESULTS

A total of 102 IDH wild-type glioblastoma were enrolled. Median follow-up was 35.9 months. The 1-, 2- and 3-year OS of "regular group" were 69.5%, 34.8%, 19.1%, and "delay group" were 69.8%, 26.1% and 13.4% respectively. Multivariate analysis showed that extent of resection (p = 0.041) was an independent prognostic factor for OS. SRI (p = 0.347), gender (p = 0.159), age (p = 0. 921), maximum diameter (p = 0.637) MGMT promoter methylation status (P = 0.630) and ki-67 expression (P = 0.974) had no effect on OS. Univariate analysis (p = 0.483) and multivariate analysis (p = 0.373) also showed that SRI had no effect on OS in glioblastoma who received gross total resection.

CONCLUSION

Appropriate extension in SRI has no negative effect on the OS of IDH wild-type glioblastoma. It is suggested that radiotherapy should be started after a good recovery from surgery. This conclusion needs further confirmed by long-term follow-up of a large sample.

Mini-craniotomy for intra-axial brain tumors: a comparison with conventional craniotomy in 306 patients harboring non-dural based lesions

The use of a mini-craniotomy approach involving linear skin incision and a bone flap of about 3 cm has been reported for several neurosurgical diseases, such as aneurysms or cranial base tumors. More superficial lesions, including intra-axial tumors, may occasionally raise concerns due to insufficient control of the tumor boundaries. The convenience of a minimally invasive approach to intrinsic brain tumors was evaluated by comparing 161 patients who underwent mini-craniotomy (MC) for intra-axial brain tumors with a group of 145 patients operated on by the same surgical team through a conventional craniotomy (CC). Groups were propensity-matched for age, preoperative condition, size and location of the tumor, and pathological diagnosis. Results were analyzed focusing on operative time, the extent of resection, clinical outcome, hospitalization time, and time to start adjuvant therapy. Mini-craniotomy was equally effective in terms of extent of resection (GTR: 70.9% in the MC group vs 70.5% in the CC group) but had shorter operative time (average: 165 min in the MC group vs 205 min in the CC group p < 0.001) and lower rate of postoperative complications both superficial (1.03% vs 6.5% in the CC group p = 0.009) and deep (4% in the MC group vs 5.5% in the CC group p = 0,47). No relationship was found between the size or location of the tumor and resection rate. The MC group had reduced hospitalization time (average: 5.8 days vs 7.6 in CC group p < 0.001) and faster access to adjuvant therapies. 92.5% of the MC patients, which were scheduled for treatment, started radiotherapy within 8 weeks after surgery as opposed to 84.1% in the CC group (p = 0.04). These findings support the increasing use of mini-craniotomy for intra-axial brain tumors.

The Role of Delayed Radiotherapy Initiation in Patients with Newly Diagnosed Glioblastoma with Residual Tumor Mass

OBJECTIVE

 Treatment for newly diagnosed isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) includes maximum safe resection, followed by adjuvant radio(chemo)therapy (RCx) with temozolomide. There is evidence that it is safe for GBM patients to prolong time to irradiation over 4 weeks after surgery. This study aimed at evaluating whether this applies to GBM patients with different levels of residual tumor volume (RV).

METHODS

 Medical records of all patients with newly diagnosed GBM at our department between 2014 and 2018 were reviewed. Patients who received adjuvant radio (chemo) therapy, aged older than 18 years, and with adequate perioperative imaging were included. Initial and residual tumor volumes were determined. Time to irradiation was dichotomized into two groups (≤28 and >28 days). Univariate analysis with Kaplan-Meier estimate and log-rank test was performed. Survival prediction and multivariate analysis were performed employing Cox proportional hazard regression.

RESULTS

 One hundred and twelve patients were included. Adjuvant treatment regimen, extent of resection, residual tumor volume, and O⁶-methylguanine DNA methyltransferase (MGMT) promoter methylation were statistically significant factors for overall survival (OS). Time to irradiation had no impact on progression-free survival (p = 0.946) or OS (p = 0.757). When stratified for different thresholds of residual tumor volume, survival predication via Cox regression favored time to irradiation below 28 days for patients with residual tumor volume above 2 mL, but statistical significance was not reached.

CONCLUSION

 Time to irradiation had no significant influence on OS of the entire cohort. Nevertheless, a statistically nonsignificant survival prolongation could be observed in patients with residual tumor volume > 2 mL when admitted to radiotherapy within 28 days after surgery.

Social determinants of health and survival on Brazilian patients with glioblastoma: a retrospective analysis of a large populational database

Background

The majority of patients diagnosed with glioblastoma develop recurrent disease resulting in poor prognoses. The current study aimed to determine the survival rates of patients diagnosed with glioblastoma in Brazil accounting for the influence of age, treatment modalities, public and private practices, and educational level using a population-based national database.

Methods

Patients diagnosed with glioblastoma from 1999-2020 were identified from The Fundação Oncocentro de São Paulo database to create a retrospective cohort. Patients were described according to age, education level treatment modalities and medical practice. In a Cox proportional hazards model, controlled for confounding factors for overall survival, the hazard ratio and 95% CI of overall survival in adults was evaluated.

Findings

A total of 4,511 patients were included. The median lengths of survival for patients treated in the public and private settings were 8 and 17 months (p<0.001), respectively. Young patients had longer median overall survival (OS: 18 to 40 years, 41 to 60 years, 61 to 65 years, 66 to 70 years and over than 70 years was 22 months, 10 months, 6 months, 5 months, 4 months, respectively (p<0.001). In general, combined treatments were associated with higher median survival compared to monotherapy. The higher educational level, the higher median survival was observed (4 months for illiterate versus 14 months for university degree). In the multivariable analyses, the significant independent predictors for overall survival were practice setting, educational level, age and treatment modalities.

Interpretation

Public practice, older patients, less intensive treatment, and lower educational level were associated with worse survival outcomes in Brazilian glioblastoma patients.

Timing of glioblastoma surgery and patient outcomes: a multicenter cohort study

Background

The impact of time-to-surgery on clinical outcome for patients with glioblastoma has not been determined. Any delay in treatment is perceived as detrimental, but guidelines do not specify acceptable timings. In this study, we relate the time to glioblastoma surgery with the extent of resection and residual tumor volume, performance change, and survival, and we explore the identification of patients for urgent surgery.

Methods

Adults with first-time surgery in 2012–2013 treated by 12 neuro-oncological teams were included in this study. We defined time-to-surgery as the number of days between the diagnostic MR scan and surgery. The relation between time-to-surgery and patient and tumor characteristics was explored in time-to-event analysis and proportional hazard models. Outcome according to time-to-surgery was analyzed by volumetric measurements, changes in performance status, and survival analysis with patient and tumor characteristics as modifiers.

Results

Included were 1033 patients of whom 729 had a resection and 304 a biopsy. The overall median time-to-surgery was 13 days. Surgery was within 3 days for 235 (23%) patients, and within a month for 889 (86%). The median volumetric doubling time was 22 days. Lower performance status (hazard ratio [HR] 0.942, 95% confidence interval [CI] 0.893–0.994) and larger tumor volume (HR 1.012, 95% CI 1.010–1.014) were independently associated with a shorter time-to-surgery. Extent of resection, residual tumor volume, postoperative performance change, and overall survival were not associated with time-to-surgery.

Conclusions

With current decision-making for urgent surgery in selected patients with glioblastoma and surgery typically within 1 month, we found equal extent of resection, residual tumor volume, performance status, and survival after longer times-to-surgery.