Gliomas are primary brain tumors derived from the neuro-epithelial tissue. According to their biological behavior and pathological appearance, the World Health Organization classified gliomas into four grades [
The current medical approach for these gliomas relies on a multimodal therapy that consists of maximal safe surgery to obtain symptomatic relief and collect brain tissue necessary for pathological diagnosis, followed by radiotherapy and/or chemotherapy to induce local control [
Stimulating the patient’s immune system to help eradicate a tumor is an approach that has been envisaged for long. There are several ways of stimulating the immune system, vaccination with mature autologous dendritic cells (DCs) being one of them. This treatment modality has already proven its safety and benefit in preclinical models [
This retrospective study focuses on the survival benefit of immunotherapy in patients with relapsed grade III gliomas included in the HGG-IMMUNO-2003 study. We aimed to compare progression-free survival (PFS), overall survival (OS), and toxicity with current data from studies in which TMZ was used. In addition, individual survival data of recurrent AA and AOD were analyzed in order to detect potential glioma subtype-specific efficiency.
Patients presenting between 2002 and 2010 with first or subsequent recurrent grade III glioma were included in this study. Relapse was defined as an increase of the tumor mass and/or augmented contrast enhancement on magnetic resonance imaging (MRI), with or without neurological symptoms. Once recurrence was confirmed, all patients underwent maximal safe surgery. None of our patients received chemotherapy thereafter. Patients were included if (1) a first or subsequent recurrent grade III glioma was documented, (2) they were between 3 and 70 years of age, (3) Karnofsky performance scale (KPS) equaled or exceeded 70 before the operation, (4) resection resulted in absent or minimal tumor volume (<2 cm³) and enough sterile and dry tumor tissue could be obtained to produce the vaccine, and (5) corticosteroids could be aborted shortly after the operation. Exclusion criteria were mentioned earlier [
Total resection required both perioperative confirmation of the neurosurgeon and absence of any residual tumor mass on MRI or computed tomography scan without contrast performed within 72 h after the intervention. All other situations were classified as subtotal.
After resection, tumor tissue was immediately transported to the laboratory where it was snap-frozen into liquid N2 without additives. To prepare tumor lysate, thawed tissue was homogenized mechanically in NaCl 0.9% containing 1% human serum albumin (HSA). After six freeze-thaw cycles, the homogenate was filtered through a Falcon filter (0.70
Peripheral blood mononuclear cells (PBMCs) were isolated from leukapheresis samples taken during the week following cessation of corticosteroids. Isolated PBMCs were kept frozen until use. Immature monocyte-derived DCs were generated out of monocytes which were obtained by adherence and loaded with autologous tumor lysate according to the procedure previously described [
Vaccines were administrated intradermally in the upper arms. After the injection, patients were kept in the hospital for observation during 30 minutes. There were four vaccination cohorts with slight modifications as described previously [
All patients underwent clinical examination and analysis by imaging. A first MRI scan was performed 12 weeks postoperatively and then every three months or earlier if patients exhibited symptoms suggesting tumor progression.
We consulted the Medline and Cochrane databases to find studies in which patients with recurrent grade III glioma were treated with TMZ and who could be used as control for our patients treated by immunotherapy. Different combinations of the following terms were used for the search: “anaplastic glioma, anaplastic astrocytoma, anaplastic oligodendroglioma, recurrence, TMZ, Temozolomide, survival” and we focused on prospective studies performed after 2000. We also included related articles. Relevant publications were critically appraised (
Statistics were calculated with Prism software (version 5.02; Graphpad Software Inc., San Diego, CA, USA). Results were represented as Kaplan-Meier survival curves and analyzed using the LogRank test.
Thirty-nine patients (median age = 43 years, ranging from 7 to 69 with 6 patients below 18 years) were included in the study. Patient data are summarized in Table
Patient characteristics.
AA | AOD | AOA | |
---|---|---|---|
18 | 13 | 8 | |
Male/female (%) | 10 (55)/8 (45) | 9 (69)/4 (31) | 7 (88)/1 (12) |
Registration period | 2004–2010 | 2004–2009 | 2002–2010 |
Median age (range) | 30 (7–62) | 42 (38–69) | 32 (11–56) |
Median | 2 | 3 | 2 |
1 event/>1 event (%) | 9 (50)/9 (50) | 5 (38)/8 (62) | 5 (63)/3 (37) |
Total/subtotal resection (%) | 11 (61)/7 (39) | 3 (23)/10 (77) | 3 (37)/5 (63) |
Initial grade III/dedifferentiation (%) | 17 (94)/1 (6) | 8 (62)/5 (38) | 3 (37)/5 (63) |
Patients alive (%) | 7 (38) | 7 (53) | 2 (25) |
AA: anaplastic astrocytoma; AOD: anaplastic oligodendroglioma; AOA: anaplastic oligoastrocytoma.
*: number of events prior to surgery and immunotherapy.
A median number of 8 (range 4–16), 8 (range 4–14), and 7 (range 4–12) vaccines were administered to the patients presenting with AA, AOD, and AOA, respectively. A median number of 5 × 106 (range 0.88–23.3 × 106) DCs was injected per vaccination.
Survival data of AA, AOD, and AOA are represented in Table
AA, AOD, and AOA characteristics.
AA | AOD | AOA | |
---|---|---|---|
Median medical history prior to immunotherapy (m) | 39.5 | 118.4 | 72 |
Median OS (m) | 20.5 | 18.8 | 13.3 |
Median PFS (m) | 4.6 | 3.4 | 7.8 |
Median interval PFS/death (m) | 15.9 | 15.4 | 5.5 |
6 months PFS (%) | 37.5 | 33.3 | 66 |
12 months PFS (%) | 37.5 | 25 | 50 |
24 months PFS (%) | 30 | 25 | 25 |
6 months OS (%) | 94.2 | 92.3 | 75 |
12 months OS (%) | 76.5 | 77 | 62.5 |
24 months OS (%) | 41.2 | 39.6 | 46.9 |
OS: Overall survival, PFS: progression free survival, AA: anaplastic astrocytoma, AOD: anaplastic oligodendroglioma, AOA: anaplastic oligoastrocytoma.
The on-line search yielded seven studies that used TMZ treatment [
Features of present and literature studies.
Immunotherapy | Yung et al. [ |
van den Bent et al. [ | Chinot et al. [ | Balmaceda et al. [ | van den Bent et al. [ | van den Bent et al. [ | Chang et al. [ | |
Year of publication | Present study | 1999 | 2003 | 2001 | 2008 | 2001 | 2003 | 2004 |
Study design | Retrospective | Prospective | Prospective | Prospective | Prospective | Prospective | Prospective | Single centre |
Study population | AA + AOA + AOD | AA+AOA | AOD | AOD + AOA | HGG | AOD + AOA | AOD + AOA | HGG |
39 (18 AA, 13 AOD, | 162 (AA = 111) | 28 | 48 (AOD = 39) | 120 (AA = 28, | 30 (AOD = 22) | 39 (AOD = 24) | 213 (AA = 53, AOA = 17) | |
TMZ protocol | / | 150–200 mg/m² | 150 mg/m² | 150–200 mg/m² | 1 × 200 mg/m² | 150–200 mg/m² | 200 mg/m² | 150–200 mg/m² |
N events | 2 or more | 2 | NS | NS | Max 3 | NS | NS | Any |
Surgery at relapse | All patients | NA | +§ | NA | NA | +§ | +§ | NA |
6 months PFS (%) | AA = 37.5 | AA = 49 | AOD = 29 | 51* | AA = 50/AOD = 58 | Responding = 44* | 71°* | 41* |
12 months PFS (%) | AA = 37.5 | AA = 24 | AOD = 11 | 25* | AA = 33/AOD = 42 | Responding = 27* | 40°* | NA |
median PFS (m) | AA = 4.45 | AA = 5.5 | AOD = 8 | NA | AA = 6/AOD = 8 | NA | Total = 10.4* Responding = 13.2* | 5.3* |
6 months OS (%) | AA = 94.2 | AA = 78 | NA | 77* | AA = 86/AOD = 75 | NA | NA | 75* |
12 months OS (%) | AA = 76.5 | AA = 56 | NA | 46* | AA = 59/AOD = 71 | NA | NA | NA |
median OS (m) | AA = 20.5 | AA = 14.2 | AOD = 12 | 10* | AA = 14.6/AOD = 18 | Responding = 7* | Not yet reached* | 12.3* |
Grade III-IV toxicity | ||||||||
Hematological (%) | No | Lymphopenia: 6 | Granulopenia and/or thrombocytopenia: 7.1 | Thrombocytopenia: 6.4 | 18 | Lymphopenia: 13.3 | Granulopenia and/or thrombocytopenia: 25.6 | 25 |
Infection (%) | No | NA | NA | NA | NA | NA | 2.6 | NA |
Nausea/vomiting (%) | no | 12 | 10.7 | NA | NA | 6.7 | 5.1 | 4 |
Hepatotoxicity (%) | No | NA | NA | NA | NA | 3.3 | NA | 1 |
Fatigue (%) | No | 6 | NA | 17 | NA | NA | NA | 4 |
Others | No | Edema (1%) | Dysphagia | NA | 2 deaths | NA | NA | Allergy |
AA: anaplastic astrocytoma; AOD: anaplastic oligodendroglioma; AOA: anaplastic oligoastrocytoma; NS: nonspecified; NA: not available; PFS: progression-free survival; OS: overall survival;
*: no subgroup details; °: not clarified whether results are from total or responding group; §: % patients that underwent surgery and % of total resection not available.
For AOD, the median OS observed in our patients was similar to the range of 10–18 months obtained with TMZ. With immunotherapy, 12 month OS concerned 77% while it ranged from 46 to 71% in patients with TMZ. Nearly forty percent of patients had an OS survival longer than 24 months when treated with immunotherapy at time of relapse.
In our study, the medical history of patients with AA was in median 78.9 months shorter than that of patients with AOD. While patients with AOD had a longer survival when measured from the moment of diagnosis, OS of AA and AOD after immunotherapy evolved similarly. Figure
Column analysis presenting median medical history for AA and AOD before and after immunotherapy. The medical history of patients with AA was in median 78.9 months shorter than that of patients with AOD while the OS after immunotherapy evolves similar. AA: anaplastic astrocytoma, AOD: anaplastic oligodendroglioma.
Since total tumor resection was previously reported to correlate with longer survival [
Kaplan-Meyer overall survival curves after immunotherapy following total or subtotal resection for all glioma grade III patients together (a), and for separate glioma subtypes; AA (b), AOD (c), and AOA (d). Survival curves were statistically compared with the LogRank test: in (a)
Dedifferentiation was defined as a grade III tumor on pathological examination of tumor tissue with previous histological diagnosis of a grade II glioma. In the case of dedifferentiated glioma grade IV (secondary GBM), earlier publications mentioned a better prognosis of dedifferentiated tumors as compared with primary glioma [
We evaluated the toxicity of immunotherapy in our patient cohort according to the CTC criteria [
This study summarizes our experiences with immunotherapy in 39 patients presenting with recurrent grade III glioma. After resection of the recurrent tumor, the patients were vaccinated with autologous mature DC loaded with autologous tumor lysate. This type of immunotherapeutic treatment has already been successfully applied in the case of grade IV gliomas [
Immunotherapy is not a stand-alone procedure but is adjuvant to tumor resection. Resection has two long-term objectives: it provides tumor tissue for preparing the lysate and it also reduces the tumor burden prior to immunotherapy. The latter point is crucial, as we have observed that the extent of resection has a prognostic effect on survival, which is in line with our earlier series of patients with grade IV relapsed glioma treated with surgery and subsequent immunotherapy [
In addition to the extent of resection, we explored in our patient group some other potential risk factors that can be associated with the immunotherapeutic treatment. In contrast with previous reports, we did not observe any survival benefit related to age, [
In the frame of our evaluation of immunotherapy as a new therapeutic opportunity for grade III gliomas, we compared our data with data on TMZ treatment. Since our study was a single-arm study, we could only compare it with literature data. The first parameter that we compared was the toxicity of the two treatments. There were no cases of grade III to IV toxicity during and after immunotherapy. TMZ, on the contrary, induced well-known grade III to IV toxicities, as described in the reference group [
PCV chemotherapy has been applied in recurrent grade III oligodendroglioma as described earlier [
Concerning survival data, our analysis showed a trend towards longer survival with immunotherapy as compared to TMZ, but inherent weaknesses of this observational study are apparent. The number of patients in both our patient and the reference group is low. In addition, although exact data are not reported, most patients in the reference group were presumably not reoperated at the time of recurrence. When analyzing data on recurrent malignancies, the medical history of the patients is very heterogeneous concerning number of events, previous surgical procedures, and radio- and/or chemotherapy. Other points of diversity include the wide range in age and vaccination details. Based on empirical observations throughout the years, preparation and administration schedule of the injections were modified [
Overall, the data presented in this study add knowledge to the growing experience about immunotherapy as a treatment for patients with malignant glioma at time of relapse. While most studies include patients with grade IV tumors, this study summarizes the results that we obtained on immunotherapy for patients with relapsed AA, AOD, and AOA. The treatment is feasible without major toxicity. The data on OS suggest that further work should be initiated on immunotherapy for recurrent grade III gliomas, particularly in those patients in whom a substantial resection can be performed.
Anapastic astrocytoma
Anaplastic oligoastrocytoma
Anaplastic oligodendroglioma
Blood-brain-barrier
Dendritic cells
Glioblastoma multiforme
Overall survival
Peripheral blood mononuclear cells
Procarbazine, lomustine, vincristine
Progression free survival
Temozolomide.
The authors would like to thank the members of the GMP laboratory facility: Goedele Stegen, Anaïs Van Hoylandt, Elke Nackers, Katja Vandenbrande, and Vallentina Schaiko. Fundings were provided by the Olivia Hendrickx Research Fund, the Herman Memorial Research Fund, the James E. Kearney Memorial Fund, FWO-V, IWT (TBM Program) and Stichting tegen Kanker. The authors are very grateful to the neuro-oncology team in the hospital for the fruitful patient discussion, and the staff of the Laboratory of Experimental Immunology for basic scientific discussions.