FLASH radiotherapy treatment planning and models for electron beams

Rahman, Mahbubur; Trigilio, Antonio; Franciosini, G.; Moeckli, Raphaël; Zhang, Rongxiao; Böhlen, Till Tobias

doi:10.1016/j.radonc.2022.08.009

Cited by 23 publications

(20 citation statements)

References 114 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hyper-radiosensitive patients are usually denied radiotherapy. Due to a lack of evidence-based data in moderately radiosensitive patients (group 2 in ATM studies) with molecularly detected iRS, no specific fractionation or technique recommendation has yet been proposed in radiosensitive patients [ 158 ]. While they should still undergo RT if RT is a mainstay of treatment for their cancer, a precautionary message may be to limit the irradiated volume and avoid severe hypofractionation.…”

Section: Practical Consequences Of a Priori Knowledge Of Irs For Prec...mentioning

confidence: 99%

The Normal, the Radiosensitive, and the Ataxic in the Era of Precision Radiotherapy: A Narrative Review

Pereira

Orlandi

Deneuve

et al. 2022

Cancers

View full text Add to dashboard Cite

(1) Background: radiotherapy is a cornerstone of cancer treatment. When delivering a tumoricidal dose, the risk of severe late toxicities is usually kept below 5% using dose-volume constraints. However, individual radiation sensitivity (iRS) is responsible (with other technical factors) for unexpected toxicities after exposure to a dose that induces no toxicity in the general population. Diagnosing iRS before radiotherapy could avoid unnecessary toxicities in patients with a grossly normal phenotype. Thus, we reviewed iRS diagnostic data and their impact on decision-making processes and the RT workflow; (2) Methods: following a description of radiation toxicities, we conducted a critical review of the current state of the knowledge on individual determinants of cellular/tissue radiation; (3) Results: tremendous advances in technology now allow minimally-invasive genomic, epigenetic and functional testing and a better understanding of iRS. Ongoing large translational studies implement various tests and enriched NTCP models designed to improve the prediction of toxicities. iRS testing could better support informed radiotherapy decisions for individuals with a normal phenotype who experience unusual toxicities. Ethics of medical decisions with an accurate prediction of personalized radiotherapy’s risk/benefits and its health economics impact are at stake; (4) Conclusions: iRS testing represents a critical unmet need to design personalized radiotherapy protocols relying on extended NTCP models integrating iRS.

show abstract

Section: Practical Consequences Of a Priori Knowledge Of Irs For Prec...mentioning

confidence: 99%

The Normal, the Radiosensitive, and the Ataxic in the Era of Precision Radiotherapy: A Narrative Review

Pereira

Orlandi

Deneuve

et al. 2022

Cancers

View full text Add to dashboard Cite

show abstract

“…The last aspect covered in this special issue is related to treatment planning considerations, two reviews by Rahman at al. [14] and Rothwell at al. [15] respectively cover electron and proton beams.…”

mentioning

confidence: 93%

FLASH Radiotherapy & Particle Therapy conference, FRPT2021

Vozenin¹,

Schüller²,

Dutreix³

et al. 2022

Radiotherapy and Oncology

View full text Add to dashboard Cite

“…[20][21][22][23][24][25][26][27] The design and optimization of such devices are further complicated by the fact that the mechanisms of action for the FLASH effect are still being debated 2,28 and precise temporal dose delivery conditions to obtain and optimize the FLASH effect are still being investigated. 29 Preclinical studies suggest that the whole treatment dose needs to be delivered in time scales of 100 ms to obtain an optimized FLASH effect. 5,30 This poses a demanding technical requirement for the delivery of conformal dose distributions in depth.…”

Section: Introductionmentioning

confidence: 99%

“…Multiple comparative VHEE treatment planning studies have unanimously concluded that VHEE RT may deliver conformal dose distributions that are superior to those from state-of -the-art intensity modulated photon RT (IMRT) techniques. [22][23][24]29,[32][33][34] For these studies, inversely optimized VHEE treatment plans were created assuming VHEE RT devices that deliver multiple (mostly seven or more) coplanar fields using small beamlets with full-width-at-half -maximum sizes of a few millimeters. However, a large amount of FBL and small scanned beamlets may not be compatible with the temporal dosedelivery requirements producing an optimized FLASH effect with a UHDR VHEE device and may result in a disproportionate size, cost, and technical complexity of the device.…”

Section: Introductionmentioning

confidence: 99%

“…UHDR RT devices proposed for the delivery of FLASH‐RT to deep‐seated targets encompass multiple beam modalities and associated delivery techniques including MV photon beams, 11 transmission (“shoot‐through”) protons, 12–16 3D patient‐specific range modulated proton and ion beams, 16–19 and very‐high energy electron (VHEE, 50−250 MeV) beams 20–27 . The design and optimization of such devices are further complicated by the fact that the mechanisms of action for the FLASH effect are still being debated 2,28 and precise temporal dose delivery conditions to obtain and optimize the FLASH effect are still being investigated 29 . Preclinical studies suggest that the whole treatment dose needs to be delivered in time scales of 100 ms to obtain an optimized FLASH effect 5,30 .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

3D‐conformal very‐high energy electron therapy as candidate modality for FLASH‐RT: A treatment planning study for glioblastoma and lung cancer

et al. 2023

Self Cite

View full text Add to dashboard Cite

BackgroundPre‐clinical ultra‐high dose rate (UHDR) electron irradiations on time scales of 100 ms have demonstrated a remarkable sparing of brain and lung tissues while retaining tumor efficacy when compared to conventional dose rate irradiations. While clinically‐used gantries and intensity modulation techniques are too slow to match such time scales, novel very‐high energy electron (VHEE, 50–250 MeV) radiotherapy (RT) devices using 3D‐conformed broad VHEE beams are designed to deliver UHDR treatments that fulfill these timing requirements.PurposeTo assess the dosimetric plan quality obtained using VHEE‐based 3D‐conformal RT (3D‐CRT) for treatments of glioblastoma and lung cancer patients and compare the resulting treatment plans to those delivered by standard‐of‐care intensity modulated photon RT (IMRT) techniques.MethodsSeven glioblastoma patients and seven lung cancer patients were planned with VHEE‐based 3D‐CRT using 3 to 16 coplanar beams with equidistant angular spacing and energies of 100 and 200 MeV using a forward planning approach. Dose distributions, dose‐volume histograms, coverage (V95%) and homogeneity (HI98%) for the planning target volume (PTV), as well as near‐maximum doses (D2%) and mean doses (Dmean) for organs‐at‐risk (OAR) were evaluated and compared to clinical IMRT plans.ResultsMean differences of V95% and HI98% of all VHEE plans were within 2% or better of the IMRT reference plans. Glioblastoma plan dose metrics obtained with VHEE configurations of 200 MeV and 3–16 beams were either not significantly different or were significantly improved compared to the clinical IMRT reference plans. All OAR plan dose metrics evaluated for VHEE plans created using 5 beams of 100 MeV were either not significantly different or within 3% on average, except for Dmean for the body, Dmean for the brain, D2% for the brain stem, and D2% for the chiasm, which were significantly increased by 1, 2, 6, and 8 Gy, respectively (however below clinical constraints). Similarly, the dose metrics for lung cancer patients were also either not significantly different or were significantly improved compared to the reference plans for VHEE configurations with 200 MeV and 5 to 16 beams with the exception of D2% and Dmean to the spinal canal (however below clinical constraints). For the lung cancer cases, the VHEE configurations using 100 MeV or only 3 beams resulted in significantly worse dose metrics for some OAR. Differences in dose metrics were, however, strongly patient‐specific and similar for some patient cases.ConclusionsVHEE‐based 3D‐CRT may deliver conformal treatments to simple, mostly convex target shapes in the brain and the thorax with a limited number of critical adjacent OAR using a limited number of beams (as low as 3 to 7). Using such treatment techniques, a dosimetric plan quality comparable to that of standard‐of‐care IMRT can be achieved. Hence, from a treatment planning perspective, 3D‐conformal UHDR VHEE treatments delivered on time scales of 100 ms represent a promising candidate technique for the clinical transfer of the FLASH effect.

show abstract

FLASH radiotherapy treatment planning and models for electron beams

Cited by 23 publications

References 114 publications

The Normal, the Radiosensitive, and the Ataxic in the Era of Precision Radiotherapy: A Narrative Review

The Normal, the Radiosensitive, and the Ataxic in the Era of Precision Radiotherapy: A Narrative Review

FLASH Radiotherapy & Particle Therapy conference, FRPT2021

3D‐conformal very‐high energy electron therapy as candidate modality for FLASH‐RT: A treatment planning study for glioblastoma and lung cancer

Contact Info

Product

Resources

About