Accelerated radiotherapy with concomitant ACNU/Ara-C for the treatment of malignant glioma

Short Course Radiotherapy Concomitant with Temozolomide in GBM Patients: A Phase II Study

Purpose

Despite recent advances, the prognosis of glioblastoma (GBM) remains poor. The aim of this study was to assess the efficacy and tolerability of multiple daily fraction radiotherapy performed with multiple temozolomide (TMZ) administrations in newly diagnosed patients with GBM.

Methods

This trial was a prospective, open-label, monocentric, nonrandomized, single arm, phase II study. The primary endpoint was the proportion of progression-free patients at 12 months, and the secondary endpoints were overall survival (OS) and toxicity. Thirty-five patients underwent two radiotherapy courses concomitant with TMZ after surgery. At each course, radiation was delivered 3 times daily, 2 Gy/fraction, for 5 consecutive days, and the total dose was 60 Gy; concurrent TMZ was administered in a total dose of 150-200 mg/m2/day.

Results

The primary endpoint failed to be applied; Macdonald criteria could be used in 16 (46%) patients with local or intracerebral recurrence (group A). In 12 patients, due to suspicion of radiation necrosis vs recurrence, Macdonald criteria were not applied (group B). The OS was 22 months, and OS probabilities at 12, 18, and 24 months were 82%, 59%, and 44%, respectively. Hematologic toxicities generally did not exceed grade 2. The quality of life and cognitive functioning did not significantly change between baseline and the first follow-up. In the multivariate analysis, necrosis and pseudoprogression were significant prognostic factors of OS.

Conclusions

To improve local control and OS, a more aggressive treatment schedule should be explored. The related higher necrosis risk and its implications regarding local control deserve further investigation.

Sustained delivery of cytarabine-loaded vesicular phospholipid gels for treatment of xenografted glioma

This study described the development of vesicular phospholipid gels (VPGs) for sustained delivery of cytarabine (Ara-C) for the treatment of xenografted glioma. Ara-C-loaded VPGs in the state of a semisolid phospholipid dispersion looked like numerous vesicles tightly packing together under the freeze-fracture electron microscopy (FF-TEM), their release profiles displayed sustained drug release up to 384 h in vitro. The biodistribution of Ara-C in the rat brain showed that Ara-C-loaded VPGs could maintain therapeutic concentrations up to 5mm distance from the implantation site in brain tissue within 28 days. At the same time, fluorescence micrograph confirmed drug distribution in brain tissue visually. Furthermore, after single administration, Ara-C-loaded VPGs group significantly inhibited the U87-MG glioma growth in right flank in comparison with Ara-C solution (p<0.01). It was explained that the entrapped drug in VPGs could avoid degradation from cytidine deaminase and sustained release of drug from Ara-C-loaded VPGs could maintain the effective therapeutic levels for a long time around the tumor. In conclusion, Ara-C-loaded VPGs, with the properties of sustained release, high penetration capacity, nontoxicity and no shape restriction of the surgical cavity, are promising local delivery systems for post-surgical sustained chemotherapy against glioma.

Sterilization stability of vesicular phospholipid gels loaded with cytarabine for brain implant

The aim of this study was to investigate the sterilization stability of cytarabine (Ara-C) loaded vesicular phospholipid gels (VPGs). VPGs were prepared by high pressure homogenization method intended for the treatment of glioblastoma multiforme (GBM) in brain as injectable implant. The particle size of VPGs after redispersion was 119.6 ± 66.24 nm, and entrapment efficiency (EE) was 32.6 ± 2.1%. Drug release in vitro from VPGs sustained for 80 h with 48.1% initial release within 1h, and rheological studies demonstrated a gel-like behavior. Comparatively, after autoclaved sterilization, increased particle size and EE were obtained as 165.6 ± 71.89 nm and 62.6 ± 2.3%, respectively. Additionally, characteristics of drug release were significantly altered with obviously prolonged release time to 450 h and remarkable reduced initial release to 24.7%. Also, the viscoelasticity was reinforced with clearly decreased fluidity. This result could be explained by the fusion of small vesicles witnessed in TEM observation, which resulted in percentages change of vesicle groups with different size. However, reduced Ara-C and increased lysophosphatidylcholine (LPC) were observed. Among the stabilizers, addition of sodium sulfite showed best effects with high stability of Ara-C and phospholipids. This may be explained by the presence of SO(3)(-), free radicals produced by sodium sulfite. Being an hydroxyl radical scavenger, it can reduce the generation of HO free radicals. These results show that, with addition of appropriate stabilizers, VPGs can be autoclaved with high stability, and it is a promising dosage form for treatment of GBM after injection into resectable or nonresectable neoplasms with sustained release properties.

Concurrent chemoradiotherapy and adjuvant chemotherapy with Topotecan for patients with glioblastoma multiforme

PURPOSE

The prognosis for patients with glioblastoma multiforme remains poor. Phase II studies, meta-analyses and a phase III study show that concurrent chemoradiotherapy has an advantage over irradiation alone. In this study the effectiveness of concurrent chemoradiotherapy with Topotecan and an adjuvant chemotherapy with Topotecan was investigated.

PATIENTS AND METHOD

Forty-two patients with predominantly unfavourable prognosis factors were included in the study and treated as follows: hyperfractionated accelerated radiotherapy (2x1.75Gy to 45.5 + 12.25 Gy (RP)) with a concurrent, continuous infusion of Topotecan (0.5 mg/m(2)/d, days 1-21). On day 28 the adjuvant chemotherapy (three courses) was begun according to the same scheme.

RESULT

Haematological toxicities were 13/42 (30%) grade III leucopenia, 2/42 (4%) grade IV, as well as 5/42 (10%) grade III thrombopenias and 1/42 (2%) grade IV. 30/42 (71%) patients showed improvement or stabilisation of an existing neurological symptomatic complex. The median time to progression was 7.2 (+/- 0.8) months, the median total survival was 10 (+/- 1.2) months, the 2 year survival rate 4.7 (+/- 0.3)%. Prognostic factors were age, surgical radicality, performance status and the tumour volume before therapy.

SUMMARY

Concurrent chemoradiotherapy and an adjuvant chemotherapy with Topotecan is feasible at acceptable toxicity levels also for patients with a moderate performance status. The patients benefit from the improvement of the clinical symptomatic complex and, even with unfavourable prognosis factors, have a higher median survival in comparison to data published on similar groups of patients given only radiotherapy.

Prolonged infusional topotecan and accelerated hyperfractionated 3d-conformal radiation in patients with newly diagnosed glioblastoma--a phase I study

PURPOSE

Topotecan has demonstrated exceptional central nervous system penetration as well as radiosensitizing properties in glioblastoma xenografts [Chastagner et al., Int J Radiat Oncol Biol Phy 50: 777-782, 2001]. This phase I trial was performed to determine the maximum tolerated dose and the recommended dose of topotecan continuous infusion administered together with concomitant radiotherapy in patients with glioblastoma.

PATIENTS AND METHODS

A total of 20 patients were treated in this trial. Twenty one day topotecan continuous infusion was escalated from 0.3 mg/m2/d in increments of 0.1 mg/m2/d and cohorts of 3-6 patients until maximum tolerated dose was reached; Three-dimensional (3d) conformal radiotherapy was applied concurrently twice daily with a fraction size of 1.75 Gy up to 57.75 Gy total dose. Three additional cycles of maintenance topotecan chemotherapy were scheduled.

RESULTS

Fifty-three courses were performed in 5 dose levels (0.3 mg/m2/d: 12 cycles, 0.4 mg/m2/d: 6 cycles, 0.5 mg/m2/d: 10 cycles, 0.6 mg/m2/d: 6 cycles, 0.7 mg/m2/d: 19 cycles). Maximum tolerated dose was reached at dose level 5 (0.7 mg/m2/d), because 3/7 patients suffered from dose limiting toxicity. These were febrile sinusitis, bacterial sepsis and grade 4 thrombocytopenia. Neutropenia of grade 4 was encountered in 2 cycles (0.5 and 0.7 mg/m2/d). Response data were available in 17 patients, 3 of which (18%) achieved partial remission, 12 (71%) stable disease throughout the observation period and 2 (11%) progressive disease.

CONCLUSION

The recommended dose for further trials will be 0.6 mg/m2/d topotecan administered as 21 days continuous infusion in combination with accelerated 3d conformal radiation.

Validation of the Medical Research Council and a newly developed prognostic index in patients with malignant glioma: how useful are prognostic indices in routine clinical practice?

Although different prognostic indices for malignant gliomas have been developed, their validity outside of clinical trials has not been widely tested. The aim of this study was to determine whether the Medical Research Council (MRC) brain tumour prognostic index was able to stratify patients for survival managed in routine practice, and secondly to compare the results with our newly developed prognostic score which included tumour grade and only 3 prognostic groups. The MRC and the new prognostic index were calculated for a group of 119 adult patients with malignant glioma managed by surgical resection/biopsy and post-operative radiotherapy. For the MRC and new score, 6 and 3 prognostic groups were defined, respectively. For all patients median survival was 11 (2-66) months. The overall survival rate at 12 and 24 months were 43% and 18%, respectively. The MRC median and two-year survival rates were 14 months and 26% for a score of 1-10, 14 months and 27% for a score of 11-15, 13 months and 22% for a score of 16-20, 8 months and 10% for a score of 21-25, 8 months and 0% for those scoring 26-33. There was only one patient in the 34-38 group. For the new prognostic index, median and two-year survival rates were respectively 16 and 26%; 12 and 23%; 8 and 7% for the good, intermediate and poor prognostic groups. Both indices were significant factors for survival in univariate analysis (MRC index, p = 0.0089, new index p = 0.0002), but not in multivariate analysis. Both the MRC and our newly devised prognostic score were able to separate patients into good and poor prognostic groups, which may aid in treatment decisions, although there was less differentiation between the MRC groups especially over the first year. Both scores use routinely available factors. However, inclusion of tumour grade in the new score may be an advantage over the MRC index.

Safety of thrice-daily hyperfractionated radiation and BCNU for high-grade gliomas

PURPOSE

To investigate the safety of thrice-daily hyperfractionated radiotherapy (RT) given in conjunction with BCNU (carmustine) in high-grade gliomas.

METHODS AND MATERIALS

Patients >18 years old with newly diagnosed high-grade gliomas were eligible. The dose of radiation was 5040 cGy, with a 1440-cGy boost in 180 cGy fractions delivered thrice daily in two 6-day periods with a 2-week interval. BCNU (200 mg/m(2)) was administered on the first day of radiation, then every 7 weeks for 1 year and every 10 weeks for another year.

RESULTS

Eighteen patients were enrolled. The mean age was 49.6 years. Sixteen patients had astrocytomas (Grade 3 or 4 in 5 and 11 patients, respectively) and 2 had oligoastrocytomas (Grade 3 and 4 in 1 patient each). One underwent total resection, 9 subtotal resection, and 8 biopsy only. Thirteen patients had stable disease, 4 regression, and 1 progression. The median time to progression was 37.8 weeks. The median overall survival was 44.4 weeks. Nine patients had neurologic toxicities, including 2 deaths at 69 and 139 weeks.

CONCLUSION

This regimen is unacceptably toxic. Factors that could have contributed to the toxicity may include the total radiation dose, thrice-daily hyperfractionation, and the concurrent use of i.v. BCNU.