Procarbazine, Lomustine And Vincristine Research Articles

PCV ALONE IN GRADE 2 AND GRADE 3 OLIGODENDROGLIOMA – LONG-TERM RESULTS FROM A UK TERTIARY CARE CENTRE

Abstract AIMS Oligodendroglioma is a subgroup of gliomas which affects young adults and has a favourable overall survival (OS) ranging between 31.5 to 56.6.% at 10 years. Standard management of these tumours is maximal safe resection followed by adjuvant radiotherapy and systemic chemotherapy with Procarbazine, Lomustine and Vincristine (PCV), or surveillance where appropriate. PCV alone is an option that helps defer or avoid radiotherapy and its neurocognitive side effects in a selected group of patients. Our retrospective study analyses outcomes with PCV alone in Oligodendroglioma. METHOD We screened patient records between 1999 to 2021 and identified 31 patients who had a histological diagnosis of grade 2/3 oligodendroglioma (with confirmation of 1p19qcodeletion on molecular testing) and received PCV alone after surgery (biopsy/ tumour resection). RESULTS Out of 31 patients, twenty-six patients were grade 2 and five patients were grade 3 oligodendroglioma. Median age was 44 years and male: female was 15:16. Median follow up was 9.5 years. Twenty-five patients (80%) presented with seizures. 80% of patients had tumour resection & twenty four patients received 5 or more cycles of PCV alone as first-line oncological treatment. There was no significant difference in outcomes for grade2/3 tumours. Eighteen patients (58%) had local tumour relapse. Fourteen patients (45%) underwent salvage radiotherapy. Median time to radiotherapy was 7 years. Median OS was 19.4 years and median progression free survival (PFS) was 13.3 years. 9 deaths were reported. CONCLUSION PCV chemotherapy alone is an effective adjuvant treatment option for selected patients with oligodendroglioma, with a favourable PFS and OS shown in our series. Its use may allow deferral of radiotherapy and avoidance of associated neurocognitive side effects which can have a detrimental effect of quality of life for these young patients.

Nimodipine Used with Vincristine: Protects Schwann Cells and Neuronal Cells from Vincristine-Induced Cell Death but Increases Tumor Cell Susceptibility.

The chemotherapeutic agent vincristine is commonly used for a variety of hematologic cancers, as well as solid tumors of the head and neck, bronchial carcinoma, as part of the procarbazine, lomustine and vincristine (PCV) regimen, for glioma. Damage to nerve tissue (neuropathy) is often dose-limiting and restricts treatment. Nimodipine is a calcium antagonist that has also shown neuroprotective properties in preliminary studies. In this approach here, we investigated the effects of the combination of vincristine and nimodipine on three cancer cell lines (A549, SAS and LN229) and neuronal cells (RN33B, SW10). Fluorescence microscopy, lactate dehydrogenase (LDH) assays and Western blot analyses were used. Nimodipine was able to enhance the cell death effects of vincristine in all tumor cells, while neuronal cells were protected and showed less cell death. There was an opposite change in the protein levels of Ak strain transforming/protein kinase B (AKT) in tumor cells (down) and neuronal cells (up), with simultaneous increased protein levels of cyclic adenosine monophosphate response element-binding protein (CREB) in all cell lines. In the future, this approach may improve tumor response to chemotherapy and reduce unwanted side effects such as neuropathy.

P07.03.A COMPLETE LONG-LASTING RESPONSE TO MULTIMODAL THIRD LINE TREATMENT WITH NEUROSURGICAL RESECTION, CARMUSTINE WAFER IMPLANTATION AND DABRAFENIB PLUS TRAMETINIB IN A BRAFV600E MUTATED HIGH-GRADE GLIOMA

Abstract BACKGROUND BRAF mutations are drivers of oncogenesis in a variety of tumors and they can be successfully targeted with small molecule inhibitors. In primary central nervous system tumors, BRAFV600E mutations are most frequently found in pleomorphic xanthoastrocytoma, ganglioglioma, pilocytic astrocytoma and epithelioid glioblastoma. Dabrafenib is a potent and selective inhibitor of BRAF-mutant kinase that was approved, as monotherapy or in combination with trametinib (mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor), for unresectable or metastatic BRAF-mutated melanoma, advanced non-small cell lung cancer and anaplastic thyroid cancer harboring BRAFV600E mutation. MATERIAL AND METHODS In February 2016, a 21-year-old female was admitted to our Unit for seizures. A brain magnetic resonance imaging (MRI) revealed a frontal contrast enhanced lesion. Neurosurgical resection was performed. The histological analysis diagnosed anaplastic pleomorphic xanthoastrocytoma (PXA) WHO grade III. A volumetric modulated radiotherapy course was delivered for a total dose of 59,4 Gy in 33 fractions with concomitant and adjuvant temozolomide therapy (Stupp protocol). In October 2017, a brain MRI showed relapsing disease. Six courses of chemotherapy with procarbazine, lomustine and vincristine (PCV) were administered, and then neurosurgical partial removal and carmustine wafer implantation were performed. The histological analysis confirmed BRAF V600E mutated anaplastic PXA. RESULTS In April 2019 the 24-year-old female patient with BRAF mutated anaplastic PXA started her third-line therapy with dabrafenib. The well-known tumor residue was less evident on the subsequent MRIs performed every three/four months. Given the literature data of the most effectiveness and the best control of the side effects, in August 2020 the patient was put on combined treatment with dabrafenib plus trametinib. Since December 2021 the residual tumor has not been longer visible. Last MRI evaluation, performed on January 26th 2023, showed no recurrence of the disease, four years after BRAF inhibitor treatment beginning. CONCLUSION Dabrafenib plus trametinib is a promising new therapy for patients affected by BRAFV600E-mutant glioma, with high overall response and manageable toxicity. Due to very poor prognosis, there are a few described cases of high-grade glioma (HGG) patients in third-line therapy, showing complete response and for such a long time. The emergence of optimized sequencing strategies and targeted agents, including multimodal treatment and systemic therapy with dabrafenib plus trametinib, will continue to broaden personalized therapy in HGG and to improve patient outcomes.

T2-Fluid-attenuated inversion recovery (FLAIR) pseudoprogression in patients with anaplastic oligodendrogliomas treated with procarbazine, lomustine and vincristine (PCV) chemotherapy alone.

Pseudoprogression in gliomas has been extensively described after radiotherapy with or without chemotherapy, but not after chemotherapy alone. Here we describe the occurrence of pseudoprogression in patients with anaplastic oligodendrogliomas treated with postoperative procarbazine, lomustine and vincristine (PCV) chemotherapy alone. We retrospectively reviewed the medical and radiological files of patients with 1p/19q codeleted, IDH-mutant anaplastic oligodendrogliomas treated with PCV chemotherapy alone who presented magnetic resonance imaging (MRI) modifications suggestive of tumour progression and in whom the final diagnosis was a pseudoprogression. We identified six patients. All patients underwent a surgical resection and were treated with PCV chemotherapy without radiotherapy. After a median of 11 months following the initiation of chemotherapy (range: 3-49 months), the patients developed asymptomatic white matter MRI modifications around the surgical cavity leading to the suspicion of a tumour progression. These modifications appeared as hyperintense on T2-fluid-attenuated inversion recovery (FLAIR) sequence, hypointense on T1 sequence, and lacked mass effect (0/6), contrast enhancement (0/6), restriction on diffusion-weighted imaging (0/4), relative cerebral blood volume (rCBV) increase on perfusion MRI (0/4), and hypermetabolism on 18 F-fluoro-L-dopa positron emission tomography (18 F-DOPA PET) scan (0/3). One patient underwent a surgical resection demonstrating no tumour recurrence; the five other patients were considered as having post-therapeutic modifications based on imaging characteristics. After a median follow-up of 4 years all patients were progression-free. Anaplastic oligodendroglioma patients treated with postoperative PCV chemotherapy alone occasionally develop T2/FLAIR hyperintensities around the surgical cavity that can wrongly suggest tumour progression. Multimodal imaging and close follow-up should be considered in this situation.

Current and Future Frontiers of Molecularly Defined Oligodendrogliomas.

Oligodendrogliomas are a subtype of adult diffuse glioma characterized by their better responsiveness to systemic chemotherapy than other high-grade glial tumors. The World Health Organization (WHO) 2021 brain tumor classification highlighted defining molecular markers, including 1p19q codeletion and IDH mutations which have become key in diagnosing and treating oligodendrogliomas. The management for patients with oligodendrogliomas includes observation or surgical resection potentially followed by radiation and chemotherapy with PCV (Procarbazine, Lomustine, and Vincristine) or Temozolomide. However, most of the available research about oligodendrogliomas includes a mix of histologically and molecularly diagnosed tumors. Even data driving our current management guidelines are based on post-hoc subgroup analyses of the 1p19q codeleted population in landmark prospective trials. Therefore, the optimal treatment paradigm for molecularly defined oligodendrogliomas is incompletely understood. Many questions remain open, such as the optimal timing of radiation and chemotherapy, the response to different chemotherapeutic agents, or what genetic factors influence responsiveness to these agents. Ultimately, oligodendrogliomas are still incurable and new therapies, such as targeting IDH mutations, are necessary. In this opinion piece, we present relevant literature in the field, discuss current challenges, and propose some studies that we think are necessary to answer these critical questions.

Clinical feasibility of modified procarbazine and lomustine chemotherapy without vincristine as a salvage treatment for recurrent adult glioma.

Procarbazine, lomustine and vincristine (PCV) chemotherapy is considered a salvage option for adult glioma; however, its significant toxicities frequently lead to dose reduction or discontinuation in patients with recurrent glioma. The current study evaluated the safety and efficacy of modified procarbazine and lomustine (PC) chemotherapy that omits vincristine and reduces the lomustine dose compared with those of conventional PCV chemotherapy. Using electronic medical records, all patients with adult recurrent glioma who received PC or PCV chemotherapy between 2009 and 2020 at Seoul St. Mary's Hospital or St. Vincent's Hospital were examined retrospectively. A total of 59 patients met the eligibility criteria. Among them, 15 patients received modified PC chemotherapy (PC group) and 44 patients received PCV chemotherapy (PCV group). The PC group presented a significantly lower hematology toxicity (anemia, 6.7 vs. 45.5%, P=0.02; thrombocytopenia 20.0 vs. 70.4%, P<0.001). Additionally, the clinical impacts of PC chemotherapy, including delay of a cycle, dose reduction, discontinuation of drug(s) or total cessation of chemotherapy, were significantly less frequent compared with the PCV group (26.7 vs. 68.2%, P=0.012). The overall survival of the PC group was also significantly longer than that of PCV group (396 vs. 232 days, P=0.042), while there was no significant difference in progression-free survival between the two groups (284.5 vs. 131 days, P=0.077). The results suggested that modified PC chemotherapy may be an alternative chemotherapeutic regimen with tolerable toxicity and without loss of clinical efficacy in patients with recurrent adult glioma. Further prospective and larger studies are required to validate our findings.

P14.14 Adjuvant treatment versus initial observation in newly diagnosed WHO grade II and grade III oligodendroglioma: real-life data from two academic, tertiary care centers in Austria

Abstract BACKGROUND Oligodendrogliomas are rare, slow-growing brain tumors with a survival prognosis of &amp;gt;10 years. Although adjuvant radio-chemotherapy has been shown to prolong survival, aggressive treatment comes at the cost of increased toxicity. Systematic data on the optimal timing of adjuvant treatment in oligodendroglioma are lacking. MATERIAL AND METHODS Patients treated for a newly diagnosed IDH-mutated, 1p/19q-codeleted oligodendroglioma (WHO grades II/III) in 2000 - 2018 at the Medical University of Vienna or the Kepler University Hospital Linz (Austria) were included in this retrospective study. Adjuvant treatment was defined as radiotherapy (RT), chemotherapy (CHT) or radio-chemotherapy (R-CHT) within 6 months after resection in the absence of progression. “Wait and see” was defined as regular follow up with magnetic resonance imaging and treatment at progression. RESULTS 185 patients were identified, comprising 123/185 (66.5%) WHO grade II and 62/185 (33.5%) WHO grade III oligodendrogliomas. Median age at diagnosis was 42 years (range: 20–82). Gross total resection (GTR) could be achieved in 77/178 (42.3%) evaluable patients. Adjuvant treatment was applied in 63/185 (38.2%) patients, of whom 43/63 (68.3%) underwent R-CHT, 9/63 (14.3%) CHT only and 11/63 (17.5%) RT only. 43/52 (82.7%) received temozolomide-based treatment, 1/52 (1.9%) procarbazine, lomustine and vincristine (PCV), 1/52 dacarbazine/fotemustine and in 7/52 (13.5%) patients, no data on used regimens was available. Adjuvant treatment was more frequently applied in WHO grade 3 tumors (p&amp;lt;0.001), while there was no association of adjuvant treatment with extent of resection (p=0.24). Patients after GTR who underwent adjuvant therapy presented with longer progression-free survival (PFS) compared to patients initially managed with observation (median: 150 months, 95%CI: 100 - not reached (n.r.) vs. median: 101 months, 95%CI: 73.2–115; p=0.053). In non-GTR tumors, patients with adjuvant therapy presented with a significantly longer median PFS of 107.5 months (95%CI: 62.8-n.r.) as compared to patients initially managed with observation (45.3 months, 95%CI: 41.2–78.8; p=0.025). CONCLUSION The application of adjuvant therapy was associated with favorable PFS in patients who underwent resection of newly diagnosed oligodendroglioma in this retrospective study. Prospective clinical trials should investigate the risks and benefits of adjuvant treatment versus initial observation in patients with oligodendroglioma.

One year of procarbazine lomustine and vincristine is poorly tolerated in low grade glioma: a real world experience in a national neuro-oncology centre

BackgroundFollowing optimal local therapy, adjuvant Procarbazine, Lomustine and Vincristine (PCV) improves overall survival (OS) in low-grade glioma (LGG). However, 1 year of PCV is associated with significant toxicities. In the pivotal RTOG 9802 randomised control trial, approximately half of the patients discontinued treatment after 6 months. As patients on clinical trials may be fitter, we aimed to further explore the tolerability of PCV chemotherapy in routine clinical practice.MethodsWe conducted a retrospective study between 2014 and 2018 at a National Neuro-Oncology centre. Patients who had received PCV during this time period were included. The primary objective was to assess tolerability of treatment. Secondary objectives included evaluation of treatment delays, dose modifications and toxicities.ResultsOverall, 41 patients were included, 24 (58%) were male and 21 (51%) aged ≥40 years. 38 (93%) underwent surgical resection and all patients received adjuvant radiotherapy prior to chemotherapy. The median number of cycles completed was 3,2,4 for procarbazine, lomustine and vincristine respectively. Only 4 (10%) completed all 6 cycles of PCV without dose modifications. There was a universal decline in dose intensity as cycles of chemotherapy progressed. Dose intensity for cycle 1 versus cycle 6 respectively: procarbazine (98% versus 46%), lomustine (94% versus 48%) and vincristine (93% versus 50%). Haematological toxicities were common. Six (14%) patients experienced Grade III-IV thrombocytopaenia and 13 (31%) experienced Grade III-IV neutropaenia.ConclusionToxicities are frequently observed with the PCV regimen in clinical practice. It might be preferable to adjust doses from the start of chemotherapy to improve tolerability or consider alternative chemotherapy, particularly in older patients with LGG.

Toxicity Profile of Procarbazine Lomustine and Vincristine Chemotherapy in Low-Grade Glioma - Retrospective Review.

BackgroundThe role of Procarbazine Lomustine and Vincristine (PCV) chemotherapy is already established in terms of improving survival in low-grade glioma (LGG). This improved survival has led to the increasing administration of PCV to LGG patients over the past years. However, like other chemotherapies, serious hematological and non-hematological toxicities may occur. The purpose of this study was to evaluate the toxicity profile of PCV and its clinical relevance in our practice. Materials and MethodsWe reviewed 63 patients of LGG retrospectively who received chemotherapy PCV between January 2015 and January 2018 at Shaukat Khanum Memorial Cancer Hospital & Research Centre, Lahore.ResultsSignificant hematological toxicity as grade 3 anemia, thrombocytopenia, and neutropenia occurred in 19%, 27%, and 46% respectively with PCV. Other toxicities such as neurotoxicity, vomiting and derangement of liver enzymes occurred in 3.2%, 19%, and 19% respectively. Patients who were on concurrent anticonvulsants had no increase in PCV toxicity. Survival was not impacted by hematological toxicities up to grade 3.ConclusionPCV chemotherapy is associated with major hematological, hepatic, and clinical toxicities (vomiting, constipation, and neuropathy). Hematological toxicities influenced the course of treatment in terms of delays and interruptions.

Abstract 1236: In vitro association of chloroquine with alkylating and antimicrotubule agents in patient derived cell lines of glioblastoma

Abstract Autophagy is an important mechanism for cell survival after chemotherapy treatment. Many preclinical and clinical trials have tried to achieve tumor remission combining alkylating agents with autophagy inhibition. Chloroquine (CQ) has a long record as an autophagy inhibitor. In previous studies it was administered in vitro with mixed effects on central nervous system cell lines: while high doses of CQ were cytotoxic, low doses were neuroprotective. Preclinical studies showed that CQ could be used to treat glioblastoma, tumors derived from glial cells in the brain. In a phase I/II clinical trial combining CQ with the standard alkylating agent (temozolomide) plus radiotherapy treating patients with glioblastoma, a dose-limiting toxicity was observed at high doses. Although the authors reported that autophagy inhibition could not be achieved, they did not describe if this mechanism was involved in tumor resistance in that cohort of patients. In order to clarify if CQ can be used to block autophagy, we performed long term treatment combining low doses of CQ with chemotherapeutic agents. We used patient derived cell lines (PDCL) from glioblastoma tumors and treated them with therapeutic agents, using the reported plasma concentration of each drug. We measured acidic organelles with acridine orange incorporation 3, 5 and 7 days after addition of the treatment with flow cytometry. Additionally, 7 days after treatment surviving cells were counted. We did not observe significant increase in autophagy levels or decrease in cell number after temozolomide treatment. On the contrary, paclitaxel induced autophagy and decreased cell survival. Interestingly the combination of procarbazine, lomustine and vincristine (PCV), induced a broad range of results, ranging from high autophagy to increased cell death. We decided to combine PCV with CQ and perform long term analysis in order to evaluate the ability of cells undergoing or escaping apoptosis, senescence or mitotic catastrophe. After 5 days nuclear morphometric analysis demonstrated that out of 6 PDCL tested, only one presented an increase in senescence. The same PDCL also presented a decrease in total number of cells and increase in p62, although combining CQ with PCV was not better than PCV alone. Our results in vitro, using low concentrations of CQ corroborate the finding in clinical trials that chloroquine does not eliminate malignant cells in glioblastoma and better autophagy inhibitors need to be developed to achieve this goal. Citation Format: Franciele C. Kipper, Ajith Thomas, Guido Lenz. In vitro association of chloroquine with alkylating and antimicrotubule agents in patient derived cell lines of glioblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1236.

HOUT-28. FIRST-LINE TEMOZOLOMIDE VS PCV FOR LOW GRADE GLIOMAS: A 11 YEARS REAL-WORLD DATA FROM CHUM, UNIVERSITY CENTER

Abstract BACKGROUND Before 2012, Temozolomide (TMZ) was used for low-grade gliomas (LGG) to avoid Lomustine toxicity. After 2012 RTOG data, Procarbazine, Lomustine and Vincristine (PCV) given sequentially with radiotherapy became standard treatment with the side effects burden associated. METHODS We retrospectively reviewed our SARDO clinical database of patients with low-grade glioma LGG grades 2 and 3 between 2006 and 2017 at CHUM University Health Center. Molecular profile for these tumors is reflex and standard in our institution since 2016. RESULTS A total of 123 patients were identified with grade 2 and grade 3 LGG; 37 (30%) treated with PCV and 86 (70%) received TMZ. Median follow up was 11mo for PCV 11mo vs 22mo TMZ. Both groups were balanced in terms of median age, sex, neurologic symptoms and surgery rate. 53% patients had tumor untested for IDH1-2 and codeletion1p19q because of diagnostic before 2016. Disparities were noted with a predominance of grade 3 in the TMZ group (74% vs 27%, p&lt; 0.01). TMZ was the preferred regimen before 2012 (100% vs 43%) and PCV became the standard of care after 2012 (0% vs 57%). Radiation use as first line treatment was 90%. The 4y OS was not significantly longer for PCV 50% compared with TMZ 47% with mOS between both groups (PCV NR vs TMZ 39.9mo, p=0.158). When controlled for tumor grade, the 2y OS was 80% for PCV vs 64% for TMZ,p=0.542. The 4y PFS was trendly longer for PCV group 78% than TMZ group 45%, p=0.148. CONCLUSION As we are still waiting for the prospective ongoing prospective trials comparing these 2 regimens, PCV and radiation are still standard of care regimens for grade 2 and 3 LGG. This retrospective data is not reassuring for a replacement for PCV with TMZ.

The Korean Society for Neuro-Oncology (KSNO) Guideline for WHO Grade III Cerebral Gliomas in Adults: Version 2019.01.

BackgroundThere was no practical guideline for the management of patients with central nervous system tumor in Korea in the past. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, developed the guideline for glioblastoma successfully and published it in Brain Tumor Research and Treatment, the official journal of KSNO, in April 2019. Recently, the KSNO guideline for World Health Organization (WHO) grade III cerebral glioma in adults has been established.MethodsThe Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searches in PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords. Scope of the disease was confined to cerebral anaplastic astrocytoma and oligodendroglioma in adults.ResultsWhenever radiological feature suggests high grade glioma, maximal safe resection if feasible is globally recommended. After molecular and histological examinations, patients with anaplastic astrocytoma, isocitrate dehydrogenase (IDH)-mutant should be primary treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy whereas those with anaplastic astrocytoma, NOS, and anaplastic astrocytoma, IDH-wildtype should be treated following the protocol for glioblastomas. In terms of anaplastic oligodendroglioma, IDH-mutant and 1p19q-codeletion, and anaplastic oligodendroglioma, NOS should be primary treated by standard brain radiotherapy and neoadjuvant or adjuvant PCV (procarbazine, lomustine, and vincristine) combination chemotherapy.ConclusionThe KSNO's guideline recommends that WHO grade III cerebral glioma of adults should be treated by maximal safe resection if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors.

Abstract CT136: STELLAR: A phase 3, randomized, open-label study to evaluate the efficacy and safety of eflornithine with lomustine compared to lomustine alone in patients with anaplastic astrocytoma that progress/recur after irradiation and adjuvant temozolomide chemotherapy

Abstract Background: Eflornithine, a novel cytostatic agent, irreversibly inhibits ornithine decarboxylase, the enzyme that catalyzes the first step in the biosynthesis of putrescine that, in conjunction with, spermidine and spermine, constitute the major polyamines of mammalian cells. More than 390 patients with high-grade gliomas have been treated with eflornithine alone or in combination with a nitrosourea or PCV (procarbazine, lomustine, and vincristine) in prior US clinical trials. In a Phase 3 randomized study of adjuvant PCV compared to PCV plus eflornithine in a total of 228 evaluable patients with anaplastic glioma (AG), overall survival (OS) was improved from a median of 61.1 months for patients on PCV to 75.8 months for patients on PCV plus eflornithine (Levin, et al., 2003). The objective of the STELLAR study (NCT02796261) is to evaluate the efficacy and safety of eflornithine with lomustine vs. lomustine in patients with anaplastic astrocytoma (AA; WHO Grade 3 glioma) who progressed/recurred after surgery, irradiation and adjuvant temozolomide chemotherapy. Methods: To be eligible for STELLAR, patients must have histologically proven AA with unequivocal evidence of first AA tumor progression or recurrence ≤ 3 months prior to randomization following surgical resection or biopsy, irradiation and temozolomide chemotherapy. Radiation therapy must have been completed ≥ 6 months prior to randomization and KPS &amp;gt; 70 is required. Approximately 280 patients will be randomized 1:1 and stratified per age (≤ 45 yrs vs &amp;gt; 45 yrs), US vs Ex-US, IDH1 status (wild type vs mutant), and number of prior surgeries (biopsy only vs 1 or 2 surgical resections). Patients will receive either eflornithine 2.8 g/m2 administered orally every 8 hours on a 2 week on, 1 week off schedule, and lomustine 110 mg/m2 administered orally once every 6 weeks, or lomustine alone dosed at 110 mg/m2 administered orally once every 6 weeks. In both arms, lomustine will be limited to a maximum of 6 cycles or 12 months of therapy. in the combination arm, eflornithine therapy can be given up to 24 months. Radiologic tumor assessment will be performed per institutional standard of care. The primary endpoint will be overall survival (OS). Secondary objectives include progression free survival (PFS) and objective response rate (ORR). The study sample size was calculated by assuming true median OS of 12 months for the treatment arm receiving lomustine monotherapy. It is hypothesized true median OS will be at least 18 months for the eflornithine plus lomustine arm. Under the assumption that OS follows an exponential probability distribution for each treatment arm, such an improvement represents a true hazard ratio of 0.667 (investigational arm/control arm). Inferential comparisons of OS will be performed using a stratified log-rank test, stratifying on the randomization stratification factors. Total accrual of approximately 274 patients (137 per treatment arm), and total information of 194 deaths is estimated to provide 80% power to detect a 33% reduction in the OS failure hazard rate. The STELLAR study is currently enrolling patients in the US, Germany and Italy and is anticipated to remain open for enrollment through the first half of 2018. Citation Format: Victor A. Levin, Scott Cruickshank. STELLAR: A phase 3, randomized, open-label study to evaluate the efficacy and safety of eflornithine with lomustine compared to lomustine alone in patients with anaplastic astrocytoma that progress/recur after irradiation and adjuvant temozolomide chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT136. doi:10.1158/1538-7445.AM2017-CT136

Re-evaluating the Efficacy and Toxicity of Procarbazine, Lomustine and Vincristine (PCV) in Relapsed Glioblastoma in the Concurrent/Adjuvant Temozolamide Era

Background: Publication of the Stupp Trial in 2005 led to adoption of concurrent/adjuvant Temozolomide(TMZ) with radiotherapy as the standard of care for fit patients with newly diagnosed Glioblastoma. No accepted standard treatment exists for relapsed disease. However, nitrosurea based regimens are commonly used. Little published evidence exists for the use of such nitrosurea based regimens in the post-Stupp era. Patients and Method: We present a retrospective study of a cohort of patients between 2009 and 2014 treated with procarbazine, lomustine and vincristine (PCV) for disease progression after completing treatment with the Stupp regime. Result: 33 patients received PCV chemotherapy having previously been treated with the Stupp regime. Median age was 47 (range 23 to 74). The median number of cycles received was 2 (range 1 to 6). Patients underwent magnetic resonance imaging (MRI) to assess response: 19%, 23% & 58% showed Partial Response, Stable, and Progressive Disease respectively. The Median Overall Survival (OS) was 26 weeks. Median Progression Free Survival (PFS) was 17 weeks with Progression Free Survival at 6 months (PFS 6) of 20%. Grade 3/4 haematological toxicity was observed in 31% of patients, of these, 18% developed grade 3/4 thrombocytopenia. Non haematological toxicities included venous thromboembolism in 13% of cases. Treatment discontinuation due to toxicities occurred in 6% of patients. Conclusion: Our experience in this cohort of patients suggests that PCV in relapsed GBM following the Stupp regimen provides modest survival benefit but is relatively well tolerated with a low risk of serious toxicity.

A multicenter study of anaplastic oligodendroglioma: the Korean Radiation Oncology Group Study 13-12.

Although some existing evidence supports the addition of chemotherapy (CT) to radiation therapy (RT) for anaplastic oligodendroglioma treatment, controversy about both the criteria for suitable candidates and the optimal treatment schedule remains. We reviewed data from 376 newly diagnosed anaplastic oliogodendroglial tumor patients from nine Korean institutes were reviewed from 2000 to 2010. Total tumor removal was performed in 146 patients. More than 85% of the entire patients received postoperative RT, and 59% received CT. Approximately 50% (n = 189) received CT in addition to RT and 9% (n = 32) received CT only. A multivariate analysis revealed that younger age, frontal lobe location of the tumor, gross total removal, 1p/19q codeletion, and initial RT were associated with longer progression-free and overall survival rates. No difference was observed in outcomes from the treatment that included either temozolomide or PCV (procarbazine, lomustine, and vincristine) in addition to RT regardless of the 1p/19q deletion status. A clear improvement in progression-free and overall survival was observed for RT and combined CT/RT in compared with CT only. Postoperative RT appears to improve survival for entire group thus total removal and 1p/19q codeletion may not be sufficient criteria to omit RT as a treatment option. These results suggest that RT should continue to be offered as the standard treatment option for patients with anaplastic oligodendroglial tumors.

P15 * COMPARATIVE OUTCOMES OF BEVACIZUMAB AND PCV CHEMOTHERAPY IN PATIENTS WITH RECURRENT AND PROGRESSIVE GLIOBLASTOMA: A RETROSPECTIVE STUDY

INTRODUCTION: Bevacizumab (Bev)is used in patients with recurrent high grade glioma in many countries; however, its efficacy has not been compared with a combination of procarbazine, lomustine and vincristine (PCV), a commonly used chemotherapy regimen in the UK. We present comparative outcomes in patients treated with Bev and PCV. METHOD: During January 2011 and March 2013, 40 patients receiving PCV and 35 patients receiving bev for recurrent and progressive glioblastoma (GBM)and anaplastic glioma (AA) were analysed for progression free survival (PFS,overall survival,and duration of neurological improvement. PFS is calculated from date of first cycle to the last cycles before radiological or neurological deterioration. RESULTS: PCV group had significantly younger patients with a median age 51 years compared to 56 in Bev group. Bev was used as I and II or III salvage line 49 and 51%, respectively. PCV was used I and II or III salvage line in 67 and 23% of patients, respectively. 6-month PFS was 38% (95%, CI 22-55%) with Bev and 22% (95%, CI 10-35%) with PCV (not significant). Similarly, superior but not significant increase in median PFS (4.7 vs. 3.3 months) and median overall survival (8.8 vs.5.4 months) were observed in Bev and PCV group, respectively. The number of patients experiencing neurological improvement was higher (57% vs.10%) and mean number of weeks of neurologically improvement compared to the mean number of weeks chemotherapy exposure were significantly longer in Bev group Bev:12/20weeks, PCV:2/1 weeks. CONCLUSION: Although statistically not significant, patients receiving Bev had better 6-month PFS and over survival . Also patients in Bev group experienced longer duration of neurological improvement.

Adjuvant treatment of anaplastic oligodendrogliomas and oligoastrocytomas.

Standard care of adjuvant treatment for anaplastic oligodendrogliomas (AO) and anaplastic oligoastrocytomas (AOA) is not yet well defined. The benefit of adjuvant chemotherapy and radiotherapy (RT), given as single modalities or sequentially, is still unclear. Furthermore, insight into the predictive and prognostic impact of various biomarkers is surging. To compare postoperative sequential RT and chemotherapy to RT alone in adults with newly diagnosed AO or mixed AOA. To evaluate the predictive and prognostic impact of the following biomarkers: codeletion of chromosomes 1p and 19q, O(6)-methylguanine-DNA methyltransferase (MGMT) promotor methylation and isocitrate dehydrogenase (IDH)-1 and -2 mutations. We searched the Cochrane Central Register for Controlled Trials (CENTRAL, Issue 1, 2014), MEDLINE (2006 to March week 2, 2014) and EMBASE (2006 to week 11, 2014). We scanned reference lists from relevant studies for any additional articles. We included randomized controlled trials (RCTs) of adults with AO, AOA or anaplastic astrocytoma (AA) comparing adjuvant treatment of chemotherapy, RT, or sequential chemotherapy and RT. We excluded no specific chemotherapy regimens. We critically appraised and extracted data from relevant studies. Based on the differences in participant selection with respect to the definition of AO (two versus three high-risk anaplastic features), the inclusion of AA and sequence of treatment (RT and chemotherapy), we could not consider the results from the three RCTs for meta-analysis. Three RCTs, with 931 participants, tested different neoadjuvant treatments: RT alone; sequential RT and procarbazine, lomustine and vincristine (PCV) chemotherapy; PCV chemotherapy alone; and temozolomide chemotherapy alone. None of the studies blinded participants or personnel, and, therefore, are considered at high risk of performance and detection bias. The studies were otherwise at low risk of bias. One study, the European Organisation for Research and Treatment of Cancer (EORTC) trial, demonstrated a statistically significant overall survival (OS) benefit for RT plus PCV, with a median OS of 3.5 years compared with 2.6 years in the RT alone arm (P value = 0.018). This result was reported 10 years after the conclusion of the enrolment, and was not apparent in the original 2008 Cochrane review. Furthermore, with retrospective evaluation of biomarkers, codeletion of complete chromosome arms 1p and 19q and IDH-1 or -2 mutation were independent prognostic factors for OS in two of the RCTs (Radiation Therapy Oncology Group (RTOG) and EORTC), and were predictive for OS in one trial (RTOG). The third trial (NOA-04) evaluated these biomarkers prospectively and found them prognostic for progression-free survival. Early PCV, either before or after RT, appears to improve OS of participants with AO or AOA. Use of biomarkers including codeletion of chromosomes 1p and 19q with or without IDH-1 or -2 mutation identify a subset of people with increased sensitivity to combined PCV and RT. The important role of biomarkers was supported in all of the RCTs examined, and prospective evaluation should be undertaken in future studies. However, PCV was associated with significant grade 3 and 4 toxicities, and whether temozolomide can be substituted for this remains unclear.

Clinical discussion of the management of anaplastic oligodendroglioma/oligoastrocytoma (both codeleted and nondeleted).

Anaplastic oligodendroglioma (AO) and anaplastic oligoastrocytoma (AOA) are uncommon malignant tumors occurring in adults, but have garnered attention because of a high rate of response to chemotherapy in early studies. However, no clinical trial had demonstrated benefit with the addition of chemotherapy to radiotherapy alone until the long-term results of RTOG 9402 and EORTC 26951. These studies revealed prolonged survival in patients with anaplastic gliomas harboring the 1p/19q codeletion when treated with PCV (procarbazine, lomustine, and vincristine) and radiation therapy compared with radiation alone. These studies validated the use of 1p/19q codeletion status as a predictive biomarker in these tumors. Additional molecular characterization of these tumors may provide additional insight into treatment decisions, although these characterizations have yet to be fully elucidated. Even with the strength of the data advocating the use of combination therapy (PCV and radiotherapy), the incorporation of newer, less-toxic drugs such as temozolomide into many practices in the past decade raises important questions regarding the optimal chemotherapy regimen. Unfortunately, additional definitive phase III trials will take several years to answer remaining questions. Regardless, it is clear that patients with 1p/19q codeleted AO or AOA who can tolerate chemotherapy should not receive radiotherapy alone.

Current and Investigational Drug Strategies for Glioblastoma

Medical treatments for glioblastoma face several challenges. Lipophilic alkylators remain the mainstay of treatment, emphasising the primacy of good blood–brain barrier penetration. Temozolomide has emerged as a major contributor to improved patient survival. The roles of procarbazine and vincristine in the procarbazine, lomustine and vincristine (PCV) schedule have attracted scrutiny and several lines of evidence now support the use of lomustine as effective single-agent therapy. Bevacizumab has had a convoluted development history, but clearly now has no major role in first-line treatment, and may even be detrimental to quality of life in this setting. In later disease, clinically meaningful benefits are achievable in some patients, but more impressively the combination of bevacizumab and lomustine shows early promise. Over the last decade, investigational strategies in glioblastoma have largely subscribed to the targeted kinase inhibitor paradigm and have mostly failed. Low prevalence dominant driver lesions such as the FGFR-TACC fusion may represent a niche role for this agent class. Immunological, metabolic and radiosensitising approaches are being pursued and offer more generalised efficacy. Finally, trial design is a crucial consideration. Progress in clinical glioblastoma research would be greatly facilitated by improved methodologies incorporating: (i) routine pharmacokinetic and pharmacodynamic assessments by preoperative dosing; and (ii) multi-stage, multi-arm protocols incorporating new therapy approaches and high-resolution biology in order to guide necessary improvements in science.

Effect of the Addition of Chemotherapy to Radiotherapy on Cognitive Function in Patients With Low-Grade Glioma: Secondary Analysis of RTOG 98-02

The addition of PCV (procarbazine, lomustine, and vincristine) chemotherapy to radiotherapy (RT) for patients with WHO grade 2 glioma improves progression-free survival (PFS). The effect of therapy intensification on cognitive function (CF) remains a concern in this population with substantial long-term survival. A total of 251 patients with WHO grade 2 glioma age ≥ 40 years with any extent of resection or age < 40 years with subtotal resection/biopsy were randomly assigned to RT (54 Gy) or RT plus PCV. We observed 111 patients age < 40 years with gross total resection. CF was assessed by Mini-Mental State Examination (MMSE) at baseline and years 1, 2, 3, and 5. Overall, few patients experienced significant decline in MMSE score. There were no significant differences in the proportion of patients experiencing MMSE score decline between the randomized study arms at any time point. Both study arms experienced a significant gain in average MMSE score longitudinally over time, with no difference between arms. The MMSE is a relatively insensitive tool, and subtle changes in CF may have been missed. However, the addition of PCV to RT did not result in significantly higher rates of MMSE score decline than RT alone through 5 years of follow-up. Patients in both randomly assigned arms experienced a statistically significant average MMSE score increase over time, with no difference between arms. The addition of PCV chemotherapy to RT improves PFS without excessive CF detriment over RT alone for patients with low-grade glioma.