CNS tumours

3436 - Low grade glioma patients with IDH mutation and 1p19q codeletion: what to do after surgery?

Date

08 Sep 2017

Session

CNS tumours

Presenters

Enrico Franceschi

Citation

Annals of Oncology (2017) 28 (suppl_5): v109-v121. 10.1093/annonc/mdx366

Authors

E. Franceschi¹, A. Mura¹, A. Mandrioli¹, S. Minichillo¹, A. Tosoni¹, A. Pession², D. De Biase², D. Danieli³, S. Pizzolitto⁴, A. Fioravanti⁵, L. Volpin⁶, R. Agati⁷, S. Bartolini¹, A. Paccapelo¹, A.A. Brandes¹

Author affiliations

¹ Medical Oncology, Ausl / Irccs Institute Of Neurological Sciences, Bellaria Hospital, 40139 - Bologna/IT
² Department Of Pharmacy And Biotechnology (dipartimento Di Farmacia E Biotecnologie) - Molecular Diagnostic Unit, Azienda USL di Bologna, University of Bologna, Bologna/IT
³ Departments Of Pathology, ULSS Vicenza, Vicenza/IT
⁴ Department Of Pathology, Santa Maria della Misericordia Hospital, Udine/IT
⁵ Neurosurgery, Ausl / Irccs Institute Of Neurological Sciences, Bellaria Hospital, 40139 - Bologna/IT
⁶ Neuroscience And Neurosurgery, San Bortolo Hospital, Vicenza/IT
⁷ Department Of Neuroradiology, Bellaria Hospital, IRCCS Institute of Neurological Sciences, Bologna/IT

Resources

Abstract 3436

Background

Molecular characterization of low grade gliomas (LGG) is essential for diagnosis and treatment of these diseases. LGG patients (pts) with IDH mutation and 1p19q codeletion (codel) are characterized by a median OS (mOS) longer than 10 years. Thus, the role of treatments and side effects should be carefully evaluated.

Methods

We evaluated LGG pts from our data warehouse (n = 679 pts) who received surgery and had sufficient tissue to assess biomarkers characterization. Pts with gliomatosis were excluded. IDH1/2 assessment was performed on formalin-fixed paraffin-embedded samples by qPCR. In wild type cases we performed NGS. 1p/19 codel analysis was performed by FISH.

Results

93 consecutive LGG with IDH mutation and codel were included. The median follow up (FU) was 96.1 months. Mean age was 40 yrs (range: 25-66); 8 pts (8.6%) underwent biopsy, 61 pts (65.6%) partial resection, 24 pts (25.8%) complete resection. 84 pts (90.3%) were considered high risk using RTOG criteria (> 40 years and/or incomplete resection). Fifty pts (53.7%) received only FU, 17 pts (18.3%) received chemotherapy (CT), 18 pts (19.4%) received radiotherapy (RT), 8 pts (8.6%) received RT + CT. Median PFS (mPFS) was 59.6 months (95%CI: 41.8-77.4) and was significantly longer in pts who received postsurgical treatments (79.5 months, 95%CI: 66.4-92.7) than pts who received FU (46.3 months, 95%CI: 36.0-56.5; P = 0.001). mPFS was 50.8 months (95%CI: 17.4-84.3), 103.6 months (95%CI: 11.7-195.6) and 120.2 months (95%CI: 40.5-199.8) in pts treated with CT alone, RT alone and RT + CT, respectively. Multivariate analysis showed that receiving a post-surgical treatment (P

Conclusions

Our study evaluated the role of treatments in LGG pts assessed with NGS and FISH. Post-surgical treatments are crucial to extend PFS in pts with IDH mutation and codel. The choice of post-surgical treatments seems to have a role, being CT alone less effective than RT and RT+CT. Longer FU is needed to provide information about OS.

Clinical trial identification

Legal entity responsible for the study

N/A

Funding

None

Disclosure

All authors have declared no conflicts of interest.