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Impact of adjuvant treatments on survival in Korean patients with WHO grade II gliomas: KNOG 15-02 and KROG 16-04 intergroup study

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Abstract

Introduction

Optimal treatment strategies for low-grade glioma (LGG) remain controversial. We analyzed treatment outcomes and evaluated prognostic factors of adult LGG patients in Korea.

Methods

We reviewed the medical records of 555 patients diagnosed with WHO grade II LGG (astrocytoma 37.8%, oligoastrocytoma 15.3%, and oligodendroglioma 46.8%) at 14 institutions between 2000 and 2010. Primary and secondary endpoints were progression-free survival (PFS) and overall survival (OS). Propensity-score matching (PSM) analyses were performed to correct imbalances in patient/tumor characteristics among adjuvant treatment groups.

Results

The median follow-up time was 83.4 months, and the 5-year PFS and OS rates were 52.2% and 83.0%, respectively. Male, older age, poorer performance status, multiple lobe involvement, and astrocytoma histology were associated with poorer survival. Among the treatment factors, gross total resection (GTR) was associated with better PFS and OS, and adjuvant chemotherapy with improved PFS. Interestingly, adjuvant radiotherapy (RT) did not improve PFS; rather, it was related with poorer OS. Regarding patient/tumor characteristics, the RT group had poorer characteristics than the non-RT group. After PSM, we detected a tendency for improved PFS in the matched RT group, and no significant difference in OS compared with the matched non-RT group.

Conclusions

The achievement of GTR is important to improve survival in LGG patients. Adjuvant chemotherapy may enhance PFS, but adjuvant RT did not improve survival outcomes. After PSM, we observed potential impacts of adjuvant RT on PFS. Our results may reflect real-world practice and consequently may help to optimize treatment strategies for LGG.

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Authors and Affiliations

  1. Department of Radiation Oncology, Hallym University Sacred Heart Hospital, Anyang, South Korea

    Taeryool Koo

  2. Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Ilwon-Ro, Gangnam-Gu, Seoul, 06351, South Korea

    Do Hoon Lim

  3. Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea

    Ho Jun Seol

  4. Department of Neurosurgery, Seoul National University College of Medicine, Seoul, South Korea

    Yun-Sik Dho

  5. Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, South Korea

    Il Han Kim

  6. Department of Neurosurgery, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea

    Jong Hee Chang

  7. Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea

    Jeongshim Lee

  8. Department of Neurosurgery, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, Hwasun, South Korea

    Tae-Young Jung

  9. Department of System Cancer Science, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, South Korea

    Ho-Shin Gwak

  10. Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, South Korea

    Kwan Ho Cho

  11. Department of Neurosurgery, Brain Tumor Center, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea

    Chang-Ki Hong

  12. Department of Radiation Oncology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea

    Ik Jae Lee

  13. Department of Neurosurgery, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea

    El Kim

  14. Department of Radiation Oncology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, South Korea

    Jin Hee Kim

  15. Department of Neurosurgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea

    Yong-Kil Hong

  16. Department of Radiation Oncology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea

    Hong Seok Jang

  17. Department of Neurosurgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea

    Chae-Yong Kim

  18. Department of Radiation Oncology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea

    In Ah Kim

  19. Department of Radiation Oncology, St. Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, South Korea

    Sung Hwan Kim

  20. Department of Radiation Oncology, Chungnam National University School of Medicine, Daejeon, South Korea

    Young Il Kim

  21. Department of Neurosurgery, Inha University Hospital, Inha University of Medicine, Inchon, South Korea

    Eun-Young Kim

  22. Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, South Korea

    Woo Chul Kim

  23. Department of Radiation Oncology, Konkuk University Medical Center, School of Medicine, Konkuk University, Seoul, South Korea

    Semie Hong

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  1. Taeryool Koo
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  2. Do Hoon Lim
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  3. Ho Jun Seol
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  13. El Kim
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  18. In Ah Kim
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  19. Sung Hwan Kim
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  20. Young Il Kim
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  21. Eun-Young Kim
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  23. Semie Hong
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Correspondence to Do Hoon Lim.

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All procedures performed in studies involving human data were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

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Koo, T., Lim, D.H., Seol, H.J. et al. Impact of adjuvant treatments on survival in Korean patients with WHO grade II gliomas: KNOG 15-02 and KROG 16-04 intergroup study. J Neurooncol 140, 445–455 (2018). https://doi.org/10.1007/s11060-018-2972-8

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