Role for cytotoxic chemotherapy in patients with recurrent glioblastoma progressing on bevacizumab: a retrospective case series

Salvage stereotactic radiosurgery for recurrent gliomas with prior radiation therapy

This study aims to assess the viability of salvage stereotactic radiosurgery (SRS) for recurrent malignant gliomas through assessing overall survival, local control and toxicity. We performed a retrospective review of 65 patients with 76 lesions (55 high-grade, 21 low-grade) treated with salvage SRS between 2002 and   2012. Median follow-up from salvage SRS was 14.9 months (IQR: 0.9-28.1), 8.3 months (IQR: 4.0-13.3) and 8.5 months (IQR: 3.9-15.8) for low-grade, high-grade, and combined, respectively. A 12-month overall survival from salvage SRS was 68.4, 38.7 and 47.3% for low-grade, high-grade and combined respectively. A total of 6-month local control was 86.2, 53.8 and 65.3% for low-grade, high-grade and combined, respectively. Our results indicate salvage SRS can provide acceptable survival and local control with minimal toxicity.

The future of high-grade glioma: Where we are and where are we going

High-grade glioma (HGG) are optimally treated with maximum safe surgery, followed by radiotherapy (RT) and/or systemic chemotherapy (CT). Recently, the treatment of newly diagnosed anaplastic glioma (AG) has changed, particularly in patients with 1p19q codeleted tumors. Results of trials currenlty ongoing are likely to determine the best standard of care for patients with noncodeleted AG tumors. Trials in AG illustrate the importance of molecular characterization, which are germane to both prognosis and treatment. In contrast, efforts to improve the current standard of care of newly diagnosed glioblastoma (GB) with, for example, the addition of bevacizumab (BEV), have been largely disappointing and furthermore molecular characterization has not changed therapy except in elderly patients. Novel approaches, such as vaccine-based immunotherapy, for newly diagnosed GB are currently being pursued in multiple clinical trials. Recurrent disease, an event inevitable in nearly all patients with HGG, continues to be a challenge. Both recurrent GB and AG are managed in similar manner and when feasible re-resection is often suggested notwithstanding limited data to suggest benefit from repeat surgery. Occassional patients may be candidates for re-irradiation but again there is a paucity of data to commend this therapy and only a minority of selected patients are eligible for this approach. Consequently systemic therapy continues to be the most often utilized treatment in recurrent HGG. Choice of therapy, however, varies and revolves around re-challenge with temozolomide (TMZ), use of a nitrosourea (most often lomustine; CCNU) or BEV, the most frequently used angiogenic inhibitor. Nevertheless, no clear standard recommendation regarding the prefered agent or combination of agents is avaliable. Prognosis after progression of a HGG remains poor, with an unmet need to improve therapy.

Retrospective study of carmustine or lomustine with bevacizumab in recurrent glioblastoma patients who have failed prior bevacizumab

BACKGROUND

Currently, there are no known effective treatments for recurrent glioblastoma once patients have progressed on a bevacizumab-containing regimen. We examined the efficacy of adding nitrosoureas to bevacizumab in patients who progressed while on an initial bevacizumab-containing regimen.

METHODS

In this retrospective study, we identified adult patients with histologically confirmed glioblastoma (WHO grade IV) who were treated with lomustine or carmustine in combination with bevacizumab as a second or third regimen after failing an alternative initial bevacizumab-containing regimen. Response rate (RR), 6-month progression free survival (PFS6), and progression-free survival (PFS) were assessed for each treatment.

RESULTS

Forty-two patients were identified (28 males) with a median age of 49 years (range, 24-78 y). Of 42 patients, 28 received lomustine (n = 22) or carmustine (n = 6) with bevacizumab as their second bevacizumab-containing regimen, and 14 received lomustine (n = 11) or carmustine (n = 3) as their third bevacizumab-containing regimen. While the median PFS for the initial bevacizumab-containing regimen was 16.3 weeks, the median PFS for the nitrosourea-containing bevacizumab regimen was 6.3 weeks. Patients had an RR of 44% and a PFS6 rate of 26% during the initial bevacizumab regimen and an RR of 0% and a PFS6 rate of 3% during the nitrosourea-containing bevacizumab regimen. There was increased grade 3-4 toxicity (45% vs 19%, P = .010) during the nitrosourea-containing bevacizumab regimen relative to the initial bevacizumab regimen. Median overall survival was 18.7 weeks from initiation of the nitrosourea-containing bevacizumab regimen.

CONCLUSION

The addition of lomustine or carmustine to bevacizumab after a patient has already progressed on a bevacizumab-containing regimen does not appear to provide benefit for most patients and is associated with additional toxicity with the doses used in this cohort.

Deferred use of bevacizumab for recurrent glioblastoma is not associated with diminished efficacy

BACKGROUND

The optimal timing to initiate bevacizumab (BV) therapy for recurrent glioblastoma (GBM) is currently unclear. To address this issue, we examined progression-free survival (PFS) and survival time (ST) in a large retrospective cohort of GBM patients treated with BV at different recurrences.

METHODS

We identified 468 primary GBM patients who underwent biopsy or surgery followed by radiation therapy and temozolomide (RT/TMZ), and then received BV. PFS and ST were compared between patients stratified by the recurrence that BV was initiated (upfront, first recurrence, second recurrence, or 3+ recurrences). We also examined the effect on PFS and ST of the addition of chemotherapy to BV. In a larger cohort of GBM patients, we determined overall treatment continuation rates at each recurrence and identified variables predictive of inability to continue treatment.

RESULTS

BV PFS was similar for all 3 recurrence groups (median, 4.1 months). There were no differences in BV ST (median, 9.8 months). The addition of chemotherapy to BV improved PFS but not ST. Analysis of treatment continuation rates indicated that the number of patients unable to undergo further treatments is modest, and that patients unable to tolerate BV delay can be identified by age ≥60 years and low extent of resection.

CONCLUSIONS

Deferred use of bevacizumab is not associated with diminished efficacy. Analysis of treatment continuation rates identified patients who may be unable to delay BV therapy. Our findings suggest that there is a fixed survival after BV initiation and that delayed BV treatment is preferable for most patients.

The Methanol Extract of Angelica sinensis Induces Cell Apoptosis and Suppresses Tumor Growth in Human Malignant Brain Tumors

Glioblastoma multiforme (GBM) is a highly vascularized and invasive neoplasm. The methanol extract of Angelica sinensis (AS-M) is commonly used in traditional Chinese medicine to treat several diseases, such as gastric mucosal damage, hepatic injury, menopausal symptoms, and chronic glomerulonephritis. AS-M also displays potency in suppressing the growth of malignant brain tumor cells. The growth suppression of malignant brain tumor cells by AS-M results from cell cycle arrest and apoptosis. AS-M upregulates expression of cyclin kinase inhibitors, including p16, to decrease the phosphorylation of Rb proteins, resulting in arrest at the G₀-G₁ phase. The expression of the p53 protein is increased by AS-M and correlates with activation of apoptosis-associated proteins. Therefore, the apoptosis of cancer cells induced by AS-M may be triggered through the p53 pathway. In in vivo studies, AS-M not only suppresses the growth of human malignant brain tumors but also significantly prolongs patient survival. In addition, AS-M has potent anticancer effects involving cell cycle arrest, apoptosis, and antiangiogenesis. The in vitro and in vivo anticancer effects of AS-M indicate that this extract warrants further investigation and potential development as a new antibrain tumor agent, providing new hope for the chemotherapy of malignant brain cancer.