The prognostic value of FET PET at radiotherapy planning in newly diagnosed glioblastoma

TY - JOUR

T1 - The prognostic value of FET PET at radiotherapy planning in newly diagnosed glioblastoma

AU - Poulsen, Sidsel Højklint

AU - Urup, Thomas

AU - Grunnet, Kirsten

AU - Christensen, Ib Jarle

AU - Larsen, Vibeke Andrée

AU - Jensen, Michael Lundemann

AU - Af Rosenschöld, Per Munck

AU - Poulsen, Hans Skovgaard

AU - Law, Ian

PY - 2017/3/1

Y1 - 2017/3/1

N2 - Background: Glioblastoma patients show a great variability in progression free survival (PFS) and overall survival (OS). To gain additional pretherapeutic information, we explored the potential of O-(2-18F-fluoroethyl)-L-tyrosine (FET) PET as an independent prognostic biomarker. Methods: We retrospectively analyzed 146 consecutively treated, newly diagnosed glioblastoma patients. All patients were treated with temozolomide and radiation therapy (RT). CT/MR and FET PET scans were obtained postoperatively for RT planning. We used Cox proportional hazards models with OS and PFS as endpoints, to test the prognostic value of FET PET biological tumor volume (BTV). Results: Median follow-up time was 14 months, and median OS and PFS were 16.5 and 6.5 months, respectively. In the multivariate analysis, increasing BTV (HR = 1.17, P < 0.001), poor performance status (HR = 2.35, P < 0.001), O(6)-methylguanine-DNA methyltransferase protein status (HR = 1.61, P = 0.024) and higher age (HR = 1.32, P = 0.013) were independent prognostic factors of poor OS. For poor PFS, only increasing BTV (HR = 1.18; P = 0.002) was prognostic. A prognostic index for OS was created based on the identified prognostic factors. Conclusion: Large BTV on FET PET is an independent prognostic factor of poor OS and PFS in glioblastoma patients. With the introduction of FET PET, we obtain a prognostic index that can help in glioblastoma treatment planning.

AB - Background: Glioblastoma patients show a great variability in progression free survival (PFS) and overall survival (OS). To gain additional pretherapeutic information, we explored the potential of O-(2-18F-fluoroethyl)-L-tyrosine (FET) PET as an independent prognostic biomarker. Methods: We retrospectively analyzed 146 consecutively treated, newly diagnosed glioblastoma patients. All patients were treated with temozolomide and radiation therapy (RT). CT/MR and FET PET scans were obtained postoperatively for RT planning. We used Cox proportional hazards models with OS and PFS as endpoints, to test the prognostic value of FET PET biological tumor volume (BTV). Results: Median follow-up time was 14 months, and median OS and PFS were 16.5 and 6.5 months, respectively. In the multivariate analysis, increasing BTV (HR = 1.17, P < 0.001), poor performance status (HR = 2.35, P < 0.001), O(6)-methylguanine-DNA methyltransferase protein status (HR = 1.61, P = 0.024) and higher age (HR = 1.32, P = 0.013) were independent prognostic factors of poor OS. For poor PFS, only increasing BTV (HR = 1.18; P = 0.002) was prognostic. A prognostic index for OS was created based on the identified prognostic factors. Conclusion: Large BTV on FET PET is an independent prognostic factor of poor OS and PFS in glioblastoma patients. With the introduction of FET PET, we obtain a prognostic index that can help in glioblastoma treatment planning.

KW - Adult

KW - Aged

KW - Brain Neoplasms/diagnostic imaging

KW - Female

KW - Glioblastoma/diagnostic imaging

KW - Humans

KW - Magnetic Resonance Imaging

KW - Male

KW - Middle Aged

KW - Positron-Emission Tomography

KW - Predictive Value of Tests

KW - Radiopharmaceuticals

KW - Radiotherapy Planning, Computer-Assisted

KW - Tomography, X-Ray Computed

KW - Tyrosine/analogs & derivatives

U2 - 10.1007/s00259-016-3494-2

DO - 10.1007/s00259-016-3494-2

M3 - Journal article

C2 - 27554774

SN - 1619-7070

VL - 44

SP - 373

EP - 381

JO - European Journal of Nuclear Medicine and Molecular Imaging

JF - European Journal of Nuclear Medicine and Molecular Imaging

IS - 3

ER -