Open Access

Long-term survival of patients suffering from glioblastoma multiforme treated with tumor-treating fields

  • Aaron Michael Rulseh1,
  • Jiří Keller1, 2,
  • Jan Klener3,
  • Jan Šroubek3,
  • Vladimír Dbalý3,
  • Martin Syrůček4,
  • František Tovaryš3 and
  • Josef Vymazal1, 5Email author
World Journal of Surgical Oncology201210:220

DOI: 10.1186/1477-7819-10-220

Received: 22 February 2012

Accepted: 13 September 2012

Published: 24 October 2012

Abstract

Glioblastoma multiforme (GBM) is the most common and malignant primary intracranial tumor, and has a median survival of only 10 to 14 months with only 3 to 5% of patients surviving more than three years. Recurrence (RGBM) is nearly universal, and further decreases the median survival to only five to seven months with optimal therapy. Tumor-treating fields (TTField) therapy is a novel treatment technique that has recently received CE and FDA approval for the treatment of RGBM, and is based on the principle that low intensity, intermediate frequency electric fields (100 to 300 kHz) may induce apoptosis in specific cell types. Our center was the first to apply TTField treatment to histologically proven GBM in a small pilot study of 20 individuals in 2004 and 2005, and four of those original 20 patients are still alive today. We report two cases of GBM and two cases of RGBM treated by TTField therapy, all in good health and no longer receiving any treatment more than seven years after initiating TTField therapy, with no clinical or radiological evidence of recurrence.

Keywords

Glioblastoma multiforme Recurrent glioblastoma multiforme Tumor-treating fields Long-term survival

Background

Glioblastoma multiforme (GBM) is the most common and malignant primary intracranial tumor, representing as much as 30% of primary brain tumors with increasing incidence in some geographic regions[1]. Its incidence has been shown to increase with age[2]. Despite the introduction of aggressive treatment with temozolomide, the median survival time of adult patients remains approximately 10 months and as high as 14 months in patients receiving combined treatment with radiotherapy[3]. Only 3 to 5% of patients survive more than three years[4], and sporadic reports of survival exceeding five years are rare[5]. The exact clinical and molecular factors that contribute to such long-term survival are still unknown; however, younger age and a high Karnofsky performance scale (KPS) are considered prognostically favorable factors[4]. Recently, MGMT gene promoter methylation and IDH1 mutation have been shown to correlate with longer survival as well[6]. Recurrence of GBM is nearly universal, and patients with recurrent glioblastoma multiforme (RGBM) fare even worse, with a median survival of only five to seven months with optimal therapy[7].

Tumor-treating fields (TTField) therapy is a novel treatment technique with the potential to treat various forms of cancer. TTField therapy is based on the principle that low intensity, intermediate frequency electric fields (100 to 300 kHz) have an anti-mitotic effect which acts during late metaphase and anaphase, with specific frequencies affecting specific cell types[8]. The applied fields disrupt mitotic spindle microtubule assembly and the segregation of intracellular organelles during cell division, leading to apoptosis[9]. TTField therapy has been tested in patients with advanced non-small cell lung cancer[10] and has recently received CE and FDA approval for the treatment of RGBM based on the results of a phase III clinical trial[11].

Our center was the first in the world to apply TTField treatment to histologically proven GBM patients in a small pilot study of 20 individuals in 2004 and 2005 (Table1). The inclusion criteria of the study included a KPS ≥70% and age ≥18 years, and the patients were divided into two groups. The first group consisted of 10 patients diagnosed with RGBM after failing temozolomide treatment that were treated with TTField therapy alone[9]. The second group consisted of 10 newly diagnosed GBM patients at least four weeks post radiation therapy (with adjuvant temozolomide)[12] that received TTField therapy combined with maintenance temozolomide. The treatment duration in individual patients varied between one and one and a half years, and all histological samples were independently examined in two laboratories in two countries. We report two cases of GBM and two cases of RGBM treated by TTField therapy, all in good health and no longer receiving any treatment more than seven years after initiating TTField treatment, with no clinical or radiological evidence of recurrence.
Table 1

Participant baseline characteristics

Patient no.

Group

Date of birth

Date of inclusion

Age at inclusion

Gender

Weight (kg)

KPS (%)

Tumor location

1

RGBM

07/1950

05/2004

53.8

Male

70

100

R. Temporoparietal

2

RGBM

08/1945

05/2004

58.8

Male

83

100

R. Temporal

3*

RGBM

06/1952

08/2004

52.2

Female

65

70

R. Parietal

4*

RGBM

08/1961

08/2004

43.1

Male

85

100

L. Frontoparietal

5

RGBM

05/1937

10/2004

67.5

Male

83

80

R. Temporoparietal

6

RGBM

05/1953

01/2005

51.7

Male

103

70

R. Parietooccipital

7

RGBM

04/1950

01/2005

54.8

Male

85

90

R. Frontotemporal

8

RGBM

06/1966

06/2005

39

Male

72

100

R. Temporoparietal

9

RGBM

06/1977

08/2005

28

Female

70

90

L. Temporoparietooccipital

10

RGBM

08/1948

09/2005

57

Female

68

70

L. Temporal

11

GBM

11/1968

01/2005

36

Male

77

100

L. Frontal

12

GBM

04/1935

05/2005

70

Male

79

90

R. Temporal

13*

GBM

12/1973

10/2005

32

Male

85

100

R. Frontal

14

GBM

03/1948

01/2006

58

Male

81

100

R. Temporal

15

GBM

10/1963

01/2006

42

Male

96

90

R. Temporal

16

GBM

03/1961

01/2006

45

Female

50

100

R. Frontal

17*

GBM

08/1973

04/2006

33

Female

65

90

R. Frontal

18

GBM

07/1951

10/2006

55

Male

80

100

L. Occipital

19

GBM

05/1941

09/2006

65

Male

85

80

L. Frontotemporal

20

GBM

05/1951

01/2007

56

Male

82

90

R. Temporal

* case in present report.

Baseline characteristics of all 20 participants in the original pilot study. Dates are presented as month/year for simplicity, age calculations were performed on exact dates.

GBM, glioblastoma multiforme (newly diagnosed); KPS, Karnofsky performance scale; L., left; No., number; R., right; RGBM, recurrent glioblastoma multiforme.

Case presentation

Case 1

A 52-year-old woman with a history of epileptic seizures and left-sided hemiparesis was diagnosed with an intra-axial brain tumor, suspected to be a high-grade glioma based on the magnetic resonance imaging (MRI) findings (Figure1a). The tumor was resected with the help of functional blood oxygen level dependence (BOLD-fMRI) neuronavigation in April 2004. Gross total resection was performed and pathological analysis revealed clear evidence of glioblastoma. Standard radiotherapy (60 Gy) and chemotherapy with temozolomide followed. After radiotherapy and chemotherapy, a follow-up MRI in July 2004 showed two enhancing lesions that were highly suspected to be tumor recurrence (Figure1b). TTField therapy was initiated in August 2004 as monotherapy. In September 2004, one month after starting TTField therapy, one of the enhancing lesions increased in size (Figure1c); however, treatment with TTField therapy was continued since the progression was asymptomatic. By February 2005, both enhancing lesions had disappeared (Figure1d) and are no longer detectable (Figure1e). TTField treatment was discontinued after one year in August 2005, with no treatment administered after that time. The last MR examination from August 2011 shows no evidence of enhancing tumor. The patient has mild, residual left-sided hemiparesis, and otherwise feels completely healthy with no subjective complaints and a KPS of 90.
https://static-content.springer.com/image/art%3A10.1186%2F1477-7819-10-220/MediaObjects/12957_2012_Article_1142_Fig1_HTML.jpg
Figure 1

Serial MR imaging in Case 1. T1-weighted image after application of contrast agent. a) April 2004, before surgery. GBM located in the right central region. b) July 2004, post-operative radiotherapy and chemotherapy. Two enhancing lesions present. c) September 2004, one month after the start of TTField therapy. The dorsal enhancing lesion increased in size, highly suspicious of tumor recurrence. d) June 2005, TTField treatment. No enhancing lesion present. e) August 2011. No enhancing lesion present. GBM, glioblastoma multiforme; MR, magnetic resonance; TTField, tumor-treating fields.

Case 2

A 41-year-old male presented with pronunciation difficulties in December 2003. Neurological examination revealed slight right-sided hemiparesis, and MRI revealed an intra-axial tumor suspected to be high-grade glioma (Figure2a). Surgery was delayed due to intercurrent infection (influenza) until March 2004, and the tumor was then partially resected. Pathological analysis revealed histological characteristics of glioblastoma. Standard radiotherapy (60 Gy) and chemotherapy with temozolomide followed. A follow-up examination in August 2004 showed an enhancing lesion suspected to be a recurrent tumor (Figure2b). TTField therapy was initiated in August 2004. By March 2005 the enhancing tumor had progressed and become cystic (Figure2c). Again, treatment with TTField therapy was continued due to the asymptomatic nature of this progression. By October 2005 the tumor had regressed (Figure2d) while the patient was still receiving TTField therapy. TTField therapy was discontinued in February 2006. A discrete, enhancing lesion is still present (last MRI in November 2011, Figure2e). This small, enhancing lesion was examined with MR spectroscopy (Figure2f) and showed noise-signal only, while the spectra in neighboring voxels were practically normal (Figure2g). Positron emission tomography (PET) did not reveal any tumor-like patterns. The patient is in good health, has minor difficulties with speech, and is completely independent, with a KPS of 90 to 100.
https://static-content.springer.com/image/art%3A10.1186%2F1477-7819-10-220/MediaObjects/12957_2012_Article_1142_Fig2_HTML.jpg
Figure 2

Serial MR imaging in Case 2. T1-weighted image after application of contrast agent. a) January 2004, before surgery. GBM located in the left frontal region. b) August 2004, post-operative radiotherapy and chemotherapy. Start of TTField treatment. An enhancing lesion suspected to be recurrent or residual tumor. c) March 2005, TTF treatment. The enhancing lesion became partly cystic. d) June 2005, regression of the cystic part. A subtle enhancing lesion still present. e) November 2011. A subtle enhancing lesion without progression. f) Proton MR spectroscopy of the enhancing lesion with dominant noise signal, suggesting gliosis rather than tumor. g) Neighboring spectrum is practically normal, demonstrating that MR spectroscopy provided reliable data from the selected slice. GBM, Glioblastoma multiforme; MR, magnetic resonance; TTField, tumor-treating fields.

Case 3

A 31-year-old male presented with an epileptic seizure in January 2005. MRI examination revealed a tumor in the right frontal lobe that was suspected to be a high grade glioma (Figure3a). The tumor was totally resected macroscopically (gross total resection) and showed clear histopathological characteristics of glioblastoma (World Health Organization (WHO) grade IV). Standard radiotherapy (60 Gy) and chemotherapy with temozolomide followed. TTField treatment was started in October 2005 concomitant to maintenance temozolomide and both treatments were discontinued in October 2006. Since that time, no tumor recurrence has been detected (Figure3b). The patient is in good health, off all treatment and with a KPS of 100.
https://static-content.springer.com/image/art%3A10.1186%2F1477-7819-10-220/MediaObjects/12957_2012_Article_1142_Fig3_HTML.jpg
Figure 3

Serial MR imaging in case 3. T1-weighted image after application of contrast agent. a) January 2005 before surgery. GBM located in the right frontal region. b) December 2011. No tumor recurrence detected. GBM, glioblastoma multiforme; MR, magnetic resonance.

Case 4

A 33-year-old female underwent MRI of the brain following an epileptic seizure in November 2005. A tentative diagnosis of high-grade glioma was made based on MRI findings (Figure4a). The tumor was completely resected macroscopically (gross total resection) in February 2006 and showed clear histopathological characteristics of glioblastoma (WHO grade IV). Standard radiotherapy (60 Gy) and chemotherapy with temozolomide followed. No recurrence was noted on follow-up MRI in February 2007 (Figure4b). TTField treatment was started in April 2006 concomitant to maintenance temozolomide and both treatments were discontinued in April 2007. No tumor recurrence has been detected on a number of follow-up MRI examinations (Figure4c), the last of which was performed in September 2011. MR spectroscopy in a small volume of tissue with corresponding increased signal intensity on Fluid Attenuated Inversion Recovery (FLAIR) images did not show a tumor-like pattern (Figure4d). Currently the patient is off all treatment, in good health, with a KPS of 100.
https://static-content.springer.com/image/art%3A10.1186%2F1477-7819-10-220/MediaObjects/12957_2012_Article_1142_Fig4_HTML.jpg
Figure 4

Serial MR imaging in case 4. T1-weighted image after application of contrast agent. a) November 2005, before surgery. GBM located in the right frontal region. b) May 2006, a small, extra-axial enhancing lesion. c) September 2011, no change of the enhancing lesion. d) FLAIR and MR spectroscopy images, September 2011. The small volume of increased signal intensity on FLAIR images did not show a tumor-like pattern on MR spectroscopy. FLAIR, Fluid Attenuated Inversion Recovery; GBM, glioblastoma multiforme; MR, magnetic resonance.

Discussion

Despite multi-modal treatment, the prognosis of GBM remains poor. Recurrence is likely inevitable provided the patient survives long enough, and further reduces the median survival to only five to seven months[4, 7]. There have been documented cases of GBM patients surviving longer than three years, termed long-term survival (LTS), representing approximately three to five percent of GBM patients[4]. Survival of GBM patients longer than five years, however, is exceptional, representing as few as 0.5% of patients[5].

Twenty percent of the participants in our pilot study (4 out of 20) have survived until the time of this report, roughly seven years (Figure5). These individuals continue to undergo regular neurological and radiological examinations, and do not show any signs of recurrence. The data from standard MR imaging are further supported by MR spectroscopy that does not show any tumor-like patterns in regions with corresponding abnormal signal intensity.
https://static-content.springer.com/image/art%3A10.1186%2F1477-7819-10-220/MediaObjects/12957_2012_Article_1142_Fig5_HTML.jpg
Figure 5

Kaplan-Meier survival curves. Kaplan-Meier survival curves for all 20 participants in the original pilot study, both as a single group and divided into recurrent and newly diagnosed glioblastoma multiforme. Two patients were lost to follow-up in the newly diagnosed group and are represented by censor marks.

Younger age and a higher KPS have been proposed as prognostically favorable parameters for longer survival[4]. The mean age of our LTS-RGBM patients (Cases 1 and 2) was 47.5 years compared to 51.5 years for the rest of the RGBM group[9]. This difference is not striking. Although we cannot completely exclude pseudo-progression or radiation necrosis in these patients diagnosed without histological verification of the recurrent lesion, their continued survival is still remarkable. In the group of newly diagnosed GBM, the mean age of LTS-GBM patients (Cases 3 and 4) was 32 years compared to 51 years for the rest of the group. This was likely a contributing factor to their long term survival; however, this does not explain seven years of disease-free survival. All of the patients in the trial had a KPS ≥70 and the median KPS was 80.

TTField therapy has been shown to effectively inhibit glioma cell replication in vitro and in vivo[8, 9]. The published results of the pilot trial using TTField therapy in GBM patients were extremely promising and served as the basis for a phase III clinical trial comparing TTField therapy to the best available active chemotherapy in patients with RGBM[11]. The phase III trial showed that patients with RGBM had comparable overall survival to those receiving chemotherapy without the side effects of chemotherapy and with a better quality of life. In the present study, no serious, probable, treatment-related adverse events occurred, with only contact dermatitis treated by topical corticosteroid documented in 17 of 20 patients. In the phase III trial, 8% of TTField therapy patients survived for longer than three years[11]. The reasons for the smaller number of long term survival patients in the phase III trial compared to the pilot trial is likely related to the younger age of the patients presented in this report, the fact that they were at their first recurrence after temozolomide (versus second to third recurrence in the phase III trial) and, most importantly, continued TTField therapy for many months, despite initial growth of the contrast enhancing lesion while on therapy. Thus, we suggest that in order to increase the probability of response to TTField therapy and subsequent long term survival, TTField treatment should be continued even in the face of initial radiologic tumor growth.

Conclusions

In the present paper we report two cases of GBM and two cases of RGBM treated by TTField therapy, all in good health and no longer receiving any treatment more than seven years after initiating TTField therapy, with no clinical or radiological evidence of recurrence. Our results indicate that TTField treatment may be remarkably successful in a subgroup of GBM/RGBM patients, and further investigation is needed to identify any unique characteristics of this patient group.

Consent

Written informed consent was obtained from all patients for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Abbreviations

BOLD-fMRI: 

Blood oxygen level dependent functional magnetic resonance imaging

FLAIR: 

Fluid Attenuated Inversion Recovery

GBM: 

Glioblastoma multiforme

KPS: 

Karnofsky performance scale

LTS: 

Long-term survival

MRI: 

Magnetic resonance imaging

PET: 

Positron emission tomography

RGBM: 

Recurrent glioblastoma multiforme

TTField: 

Tumor-treating fields

WHO: 

World Health Organization.

Declarations

Acknowledgements

Manuscript preparation was supported by Research Grant IGA MZ CR NS9654-4/2008.

JV, AMR, JiK and JaK were supported by Na Homolce Hospital, Research Grant IGA MZ CR NS9654-4/2008.

JS, VD, MS and FT were supporrted by Na Homolce Hospital.

JK was supported by Research Project Charles University in Prague, PRVOUK P34 and Research Grant IGA MZCR NT11328-4/2010.

The funding body played no role in the collection, analysis and interpretation of data, in the writing of the manuscript or in the decision to submit the manuscript for publication.

Authors’ Affiliations

(1)
Department of Radiology, Na Homolce Hospital
(2)
3rd Medical Faculty, Charles University in Prague
(3)
Department of Neurosurgery, Na Homolce Hospital
(4)
Department of Pathology, Na Homolce Hospital
(5)
Department of Neurology, 1st Medical Faculty, Charles University in Prague

References

  1. Dobes M, Khurana VG, Shadbolt B, Jain S, Smith SF, Smee R, Dexter M, Cook R: Increasing incidence of glioblastoma multiforme and meningioma, and decreasing incidence of Schwannoma (2000–2008): findings of a multicenter Australian study. Surg Neurol Int. 2011, 2: 176-10.4103/2152-7806.90696.PubMed CentralView ArticlePubMed
  2. Dubrow R, Darefsky AS: Demographic variation in incidence of adult glioma by subtype, United States, 1992–2007. BMC Cancer. 2011, 11: 325-10.1186/1471-2407-11-325.PubMed CentralView ArticlePubMed
  3. Johnson DR, O’Neill BP: Glioblastoma survival in the United States before and during the temozolomide era. J Neurooncol. 2012, 107: 359-364. 10.1007/s11060-011-0749-4.View ArticlePubMed
  4. Krex D, Klink B, Hartmann C, von Deimling A, Pietsch T, Simon M, Sabel M, Steinbach JP, Heese O, Reifenberger G, Weller M, Schackert G: Long-term survival with glioblastoma multiforme. Brain. 2007, 130: 2596-2606. 10.1093/brain/awm204.View ArticlePubMed
  5. Deb P, Sharma MC, Mahapatra AK, Agarwal D, Sarkar C: Glioblastoma multiforme with long term survival. Neurol India. 2005, 53: 329-332. 10.4103/0028-3886.16934.View ArticlePubMed
  6. Weller M, Felsberg J, Hartmann C, Berger H, Steinbach JP, Schramm J, Westphal M, Schackert G, Simon M, Tonn JC, Heese O, Krex D, Nikkhah G, Pietsch T, Wiestler O, Reifenberger G, von Deimling A, Loeffler M: Molecular predictors of progression-free and overall survival in patients with newly diagnosed glioblastoma: a prospective translational study of the German Glioma Network. J Clin Oncol. 2009, 27: 5743-5750. 10.1200/JCO.2009.23.0805.View ArticlePubMed
  7. Henriksson R, Asklund T, Poulsen HS: Impact of therapy on quality of life, neurocognitive function and their correlates in glioblastoma multiforme: a review. J Neurooncol. 2011, 104: 639-646. 10.1007/s11060-011-0565-x.PubMed CentralView ArticlePubMed
  8. Kirson ED, Gurvich Z, Schneiderman R, Dekel E, Itzhaki A, Wasserman Y, Schatzberger R, Palti Y: Disruption of cancer cell replication by alternating electric fields. Cancer Res. 2004, 64: 3288-3295. 10.1158/0008-5472.CAN-04-0083.View ArticlePubMed
  9. Kirson ED, Dbalý V, Tovarys F, Vymazal J, Soustiel JF, Itzhaki A, Mordechovich D, Steinberg-Shapira S, Gurvich Z, Schneiderman R, Wasserman Y, Salzberg M, Ryffel B, Goldsher D, Dekel E, Palti Y: Alternating electric fields arrest cell proliferation in animal tumor models and human brain tumors. Proc Natl Acad Sci U S A. 2007, 104: 10152-10157. 10.1073/pnas.0702916104.PubMed CentralView ArticlePubMed
  10. Pless M, Weinberg U: Tumor treating fields: concept, evidence and future. Expert Opin Investig Drugs. 2011, 20: 1099-1106. 10.1517/13543784.2011.583236.View ArticlePubMed
  11. Wong ET, Ram Z, Gutin PH, Stupp R: Updated survival data of the Phase III clinical trial of Novottf-100a versus best standard chemotherapy for recurrent glioblastoma. Neuro-Oncol. 2011, 13: iii85-iii91. 10.1093/neuonc/nor154.
  12. Stupp R, Mason WP, van den Bent MJ, Weller M, Fisher B, Taphoorn MJB, Belanger K, Brandes AA, Marosi C, Bogdahn U, Curschmann J, Janzer RC, Ludwin SK, Gorlia T, Allgeier A, Lacombe D, Cairncross JG, Eisenhauer E, Mirimanoff RO: Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med. 2005, 352: 987-996. 10.1056/NEJMoa043330.View ArticlePubMed

Copyright

© Rulseh et al.; licensee BioMed Central Ltd. 2012

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://​creativecommons.​org/​licenses/​by/​2.​0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Advertisement