The FLASH effect depends on oxygen concentration

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

OBJECTIVE: Recent in vivo results have shown prominent tissue sparing effect of radiotherapy with ultra-high dose rates (FLASH) compared to conventional dose rates (CONV). Oxygen depletion has been proposed as the underlying mechanism, but in vitro data to support this have been lacking. The aim of the current study was to compare FLASH to CONV irradiation under different oxygen concentrations in vitro. METHODS: Prostate cancer cells were irradiated at different oxygen concentrations (relative partial pressure ranging between 1.6 and 20%) with a 10 MeV electron beam at a dose rate of either 600 Gy/s (FLASH) or 14 Gy/min (CONV), using a modified clinical linear accelerator. We evaluated the surviving fraction of cells using clonogenic assays after irradiation with doses ranging from 0 to 25 Gy. RESULTS: Under normoxic conditions, no differences between FLASH and CONV irradiation were found. For hypoxic cells (1.6%), the radiation response was similar up to a dose of about 5-10 Gy, above which increased survival was shown for FLASH compared to CONV irradiation. The increased survival was shown to be significant at 18 Gy, and the effect was shown to depend on oxygen concentration. CONCLUSION: The in vitro FLASH effect depends on oxygen concentration. Further studies to characterize and optimize the use of FLASH in order to widen the therapeutic window are indicated. ADVANCES IN KNOWLEDGE: This paper shows in vitro evidence for the role of oxygen concentration underlying the difference between FLASH and CONV irradiation.

Detaljer

Författare
Enheter & grupper
Externa organisationer
  • Skåne University Hospital
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Biomedicinsk laboratorievetenskap/teknologi
Originalspråkengelska
Artikelnummer20190702
TidskriftBritish Journal of Radiology
Volym93
Utgåva nummer1106
StatusPublished - 2019 dec 20
PublikationskategoriForskning
Peer review utfördJa

Related projects

Gabriel Adrian, Claus E Andersen, Mattias Belting, Karl Butterworth, Sven Bäck, Crister Ceberg, Silke Engelholm, Jacob Engellau, Anders Hansen, Elise Konradsson, Michael Lempart, Stephen McMahon, Roger Olsson, Kristoffer Petersson & Per Munck af Rosenschöld

2019/01/01 → …

Projekt: ForskningInternationellt samarbete

Visa alla (1)