Dose mimicking based strategies for online adaptive proton therapy of head and neck cancer

Villarroel, Elena Lucia Borderias; Fredriksson, Albin; Cvilic, Sophie; Perri, Dario Di; Longton, E.; Pierrard, Julien; Geets, Xavier; Sterpin, Edmond

doi:10.1088/1361-6560/accb38

Cited by 3 publications

References 44 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

A fast and robust constraint-based online re-optimization approach for automated online adaptive intensity modulated proton therapy in head and neck cancer

Oud,

Breedveld,

Rojo-Santiago

et al. 2024

Phys. Med. Biol.

View full text Add to dashboard Cite

Objective – In head-and-neck cancer intensity modulated proton therapy (IMPT), adaptive radiotherapy is currently restricted to offline re-planning, mitigating the effect of slow changes in patient anatomies. Daily online adaptations can potentially improve dosimetry. Here, a new, fully automated online re-optimization strategy is presented. In a retrospective study, this online re-optimization approach was compared to our trigger-based offline re-planning (offlineTB re-planning) schedule, including extensive robustness analyses.Approach – The online re-optimization method employs automated multi-criterial re-optimization, using robust optimization with 1 mm setup-robustness settings (in contrast to 3 mm for offlineTB re-planning). Hard planning constraints and spot addition are used to enforce adequate target coverage, avoid prohibitively large maximum doses and minimize organ-at-risk doses. For 67 repeat-CTs from 15 patients, fraction doses of the two strategies were compared for the CTVs and organs-at-risk. Per repeat-CT, 10.000 fractions with different setup and range robustness settings were simulated using Polynomial Chaos Expansion for fast and accurate dose calculations. Main results – For 14/67 repeat-CTs, offlineTB re-planning resulted in <50% probability of D98%≥95% of the prescribed dose (Dpres) in one or both CTVs, which never happened with online re-optimization. With offlineTB re-planning, eight repeat-CTs had zero probability of obtaining D98%≥95%Dpres for CTV7000, while the minimum probability with online re-optimization was 81%. Risks of xerostomia and dysphagia grade ≥ II were reduced by 3.5 ± 1.7 and 3.9 ± 2.8 percentage point [mean ± SD] (p<10-5 for both). In online re-optimization, adjustment of spot configuration followed by spot-intensity re-optimization took 3.4 minutes on average. Significance – The fast online re-optimization strategy always prevented substantial losses of target coverage caused by day-to-day anatomical variations, as opposed to the clinical trigger-based offline re-planning schedule. On top of this, online re-optimization could be performed with smaller setup robustness settings, contributing to improved organs-at-risk sparing.

show abstract

A fast and robust constraint-based online re-optimization approach for automated online adaptive intensity modulated proton therapy in head and neck cancer

Oud,

Breedveld,

Rojo-Santiago

et al. 2024

Phys. Med. Biol.

View full text Add to dashboard Cite

show abstract

Adaptive intensity modulated proton therapy using 4D robust planning: a proof-of-concept for the application of dose mimicking approach

Kaushik,

Stützer,

Ödén

et al. 2024

Phys. Med. Biol.

View full text Add to dashboard Cite

Objective. A four-dimensional robust optimisation (4DRO) is usually employed when the tumour respiratory motion needs to be addressed. However, it is computationally demanding, and an automated method is preferable for adaptive planning to avoid manual trial-and-error. This study proposes a 4DRO technique based on dose mimicking for automated adaptive planning. Approach. Initial plans for 4DRO intensity modulated proton therapy were created on an average CT for four patients with clinical target volume (CTV) in the lung, oesophagus, or pancreas, respectively. These plans were robustly optimised using three phases of four-dimensional computed tomography (4DCT) and accounting for setup and density uncertainties. Weekly 4DCTs were used for adaptive replanning, using a constant relative biological effectiveness (cRBE) of 1.1. Two methods were used: (1) template-based adaptive (TA) planning and (2) dose-mimicking-based adaptive (MA) planning. The plans were evaluated using variable RBE (vRBE) weighted doses and biologically consistent dose accumulation (BCDA). Main results. MA and TA plans had comparable CTV coverage except for one patient where the MA plan had a higher D98 and lower D2 but with an increased D2 in few organs at risk (OARs). CTV D98 deviations in non-adaptive plans from the initial plans were up to −7.2 percentage points (p.p.) in individual cases and −1.8 p.p. when using BCDA. For the OARs, MA plans showed a reduced mean dose and D2 compared to the TA plans, with few exceptions. The vRBE-weighted accumulated doses had a mean dose and D2 difference of up to 0.3 Gy and 0.5 Gy, respectively, in the OARs with respect to cRBE-weighted doses. Significance. MA plans indicate better performance in target coverage and OAR dose sparing compared to the TA plans in 4DRO adaptive planning. Moreover, MA method is capable of handling both forms of anatomical variation, namely, changes in density and relative shifts in the position of OARs.

show abstract

Dosimetric Advantages of Adaptive Impt vs. Enhanced Workload and Treatment Time – a Need for Automation

Oud,

Breedveld,

Giżyńska

et al. 2024

Preprint

View full text Add to dashboard Cite

Dose mimicking based strategies for online adaptive proton therapy of head and neck cancer

Cited by 3 publications

References 44 publications

A fast and robust constraint-based online re-optimization approach for automated online adaptive intensity modulated proton therapy in head and neck cancer

A fast and robust constraint-based online re-optimization approach for automated online adaptive intensity modulated proton therapy in head and neck cancer

Adaptive intensity modulated proton therapy using 4D robust planning: a proof-of-concept for the application of dose mimicking approach

Dosimetric Advantages of Adaptive Impt vs. Enhanced Workload and Treatment Time – a Need for Automation

Contact Info

Product

Resources

About