Retrospective Analysis of Radiological Recurrence Patterns in Glioblastoma, Their Prognostic Value And Association to Postoperative Infarct Volume

Recent studies suggested that postoperative hypoxia might trigger invasive tumor growth, resulting in diffuse/multifocal recurrence patterns. Aim of this study was to analyze distinct recurrence patterns and their association to postoperative infarct volume and outcome. 526 consecutive glioblastoma patients were analyzed, of which 129 met our inclusion criteria: initial tumor diagnosis, surgery, postoperative diffusion-weighted imaging and tumor recurrence during follow-up. Distinct patterns of contrast-enhancement at initial diagnosis and at first tumor recurrence (multifocal growth/progression, contact to dura/ventricle, ependymal spread, local/distant recurrence) were recorded by two blinded neuroradiologists. The association of radiological patterns to survival and postoperative infarct volume was analyzed by uni-/multivariate survival analyses and binary logistic regression analysis. With increasing postoperative infarct volume, patients were significantly more likely to develop multifocal recurrence, recurrence with contact to ventricle and contact to dura. Patients with multifocal recurrence (Hazard Ratio (HR) 1.99, P = 0.010) had significantly shorter OS, patients with recurrent tumor with contact to ventricle (HR 1.85, P = 0.036), ependymal spread (HR 2.97, P = 0.004) and distant recurrence (HR 1.75, P = 0.019) significantly shorter post-progression survival in multivariate analyses including well-established prognostic factors like age, Karnofsky Performance Score (KPS), therapy, extent of resection and patterns of primary tumors. Postoperative infarct volume might initiate hypoxia-mediated aggressive tumor growth resulting in multifocal and diffuse recurrence patterns and impaired survival

Prognostic value of tumour volume in patients with a poor Karnofsky performance status scale – a bicentric retrospective study

Backround: Median overall survival (OS) after diagnosis of glioblastoma (GBM) remains 15 months amongst patients receiving aggressive surgical resection, chemotherapy and irradiation. Treatment of patients with a poor preoperative Karnofsky Performance Status Scale (KPSS) is still controversial. Therefore, we retrospectively assessed the outcome after surgical treatment in patients with a KPSS of ≤60%. Methods: We retrospectively included patients with a de-novo glioblastoma WHO °IV and preoperative KPSS ≤60%, who underwent surgery at two neurosurgical centres between September 2006 and March 2016. We recorded pre- and postoperative tumour volume, pre- and postoperative KPSS, OS, age and MGMT promoter status. Results: One hundred twenty-three patients (58 females/65 males, mean age 67.4 ± 13.4 years) met the inclusion criteria. Seventy-five of the 123 patients (61%) underwent surgical resection. 48/123 patients (39%) received a biopsy. The median preoperative and postoperative tumour volume of all patients was 33.0 ± 31.3 cm3 (IR 15.0–56.5cm3) and 3.1 ± 23.8 cm3 (IR 0.2–15.0 cm3), respectively. The median KPSS was 60% (range 20–60%) preoperatively and 50% (range 0–80%) postoperatively. Patients who received a biopsy showed a median OS for patients who received a biopsy only was 3.0 months (95% CI 2.0–4.0 months), compared to patients who had a resection and had a median OS of 8 months (95% CI 3.1–12.9 months). Age (p < 0.001, HR: 1.045 [95% CI 1.022–1.068]), postoperative tumour volume (p = 0.02, HR: 1.016 [95% CI 1.002–1.029]) and MGMT promotor status (p = 0.016, HR: 0.473 [95% CI 0.257–0.871]) were statistically significant in multivariate analysis. In subgroup analyses only age was shown as a significant prognostic factor in multivariate analyses for patients receiving surgery (p < 0.001, HR: 1.046 [95% CI 1.022–1.072]). In the biopsy group no significant prognostic factors were shown in multivariate analysis. Conclusion: GBM patients with a preoperative KPSS of ≤60% might profit from surgical reduction of tumour burden

Adjuvant stereotactic fractionated radiotherapy to the resection cavity in recurrent glioblastoma – the GlioCave study (NOA 17 – ARO 2016/3 – DKTK ROG trial)

Abstract Background Glioblastoma relapses in the vast majority of cases within 1 year. Maximum safe resection of the recurrent glioblastoma can be offered in some cases. Re-irradiation has been established for the treatment of recurrent glioblastoma, too. In both cases, adjuvant treatment, mostly using temozolomide, can improve PFS and OS after these interventions. However, combining gross tumor resection and adjuvant re-radiotherapy to the resection cavity has not been tested so far. Methods/Design In the multicenter two-armed randomized Phase II GlioCave Study, fractionated stereotactic radiotherapy to the resection cavity, after gross tumor resection of recurrent glioblastoma, will be compared to observation. Depending on the size of the target volume, a total dose of 46 Gy in 2 Gy per fraction or a total dose if 36 Gy in 3 Gy per fraction will be applied. Progression free survival will be the primary endpoint of the study. Discussion Adjuvant treatment after gross tumor resection of recurrent glioblastoma is currently deemed to be limited to chemotherapy. However, re-irradiation has proven safety and tolerability in the treatment of macroscopic disease. Performing re-irradiation as an adjuvant measure after gross tumor resection has not been tested so far. The GlioCave Study will investigate the efficacy and the safety profile of this approach. Trial registration The trial was prospectively registered at clinicaltrials.gov ( NCT02715297 , registration date February 29th, 2016). The protocol presented hereby refers to the version 1.2 of the protocol (January 11th, 2017)

A trend towards a more intense adjuvant treatment of low-grade-gliomas in tertiary centers in Germany after RTOG 9802 – results from a multi-center survey

Abstract Background The treatment recommendations for Low-grade Gliomas (LGG) underwent profound changes due to results from RTOG 9802 published in April 2016. This work aims to investigate whether the results from the trial were already incorporated into the treatment recommendations at German oncology centers before an update of the official guidelines. Methods An online based questionnaire with questions covering all aspects of adjuvant treatments of LGGs was generated, including three cases with distinct clinical situations. We contacted all members of the neuro-oncologic working group (NOA) of the German Cancer Society (DKG) as well as all German-speaking members of the European Low-Grade Glioma Network via E-mail. Results We collected 38 responses. All responders were at least specialists; they predominantly worked at tertiary hospitals with a high volume of LGGs treated annually (75% with more than 10 cases per year). All responders stated to consent treatment recommendation for LGGs within interdisciplinary oncologic boards. The treatment recommendations for LGGs changed profoundly between 2015 and 12/2016. There is a trend towards PCV-based multimodal treatments, especially for oligodendroglial LGGs, as well as a trend away from watchful-waiting-policies for astrocytic LGGs. Conclusion Neurooncologists do adapt results from clinical trials quickly. None the less, there is still an immense heterogeneity within the treatment recommendations, predominantly for astrocytic LGGs. Well planned clinical trials and concise treatment recommendations are warranted; additionally, individual counseling of patients is essential

Does age really matter? Radiotherapy in elderly patients with glioblastoma, the Munich experience

Abstract Background Glioblastoma is usually diagnosed around the age of 60–70 years. Patients older than 65 years are frequently described as “elderly”. Several trials with monotherapy have established treatment regimens that offer therapies with reduced side effects but reduced efficacy. We analysed the outcome of elderly glioblastoma patients treated at our facility. Methods We performed a retrospective analysis of 62 consecutive patients older than 65 years treated for a primary glioblastoma at our facility from 2009 to 2015. Results Median age was 69.6 years (range 65.1–85.6 years); median OS of the entire cohort was 10.9 months. ECOG, MGMT and extent of resection but not age and the time from surgery to radiotherapy were associated with longer survival. Patients treated with adjuvant chemotherapy had a significantly longer survival (20.5 vs. 7.8 months). Furthermore, salvage therapies were associated with significant improved survival when compared to Best Supportive Care (22.3 vs. 8.8 months). Conclusion Also elderly patients are likely to benefit from an aggressive treatment after primary diagnosis of glioblastoma