Radiation-Induced Toxicity Risks in Photon Versus Proton Therapy for Synchronous Bilateral Breast Cancer.
Author
Stick, Line BjerregaardJensen, Maria Fuglsang
Bentzen, Søren M
Kamby, Claus
Lundgaard, Anni Young
Maraldo, Maja Vestmø
Offersen, Birgitte Vrou
Yu, Jen
Vogelius, Ivan Richter
Date
2021-11-11Journal
International Journal of Particle Therapy,Publisher
Particle Therapy Co-Operative GroupType
Article
Metadata
Show full item recordAbstract
PURPOSE: This study compares photon and proton therapy plans for patients with synchronous bilateral early breast cancer and estimates risks of early and late radiation-induced toxicities. MATERIALS AND METHODS: Twenty-four patients with synchronous bilateral early breast cancer receiving adjuvant radiation therapy using photons, 3-dimensional conformal radiation therapy or volumetric modulated arc therapy, were included and competing pencil beam scanning proton therapy plans were created. Risks of dermatitis, pneumonitis, acute esophageal toxicity, lung and breast fibrosis, hypothyroidism, secondary lung and esophageal cancer and coronary artery events were estimated using published dose-response relationships and normal tissue complication probability (NTCP) models. RESULTS: The primary clinical target volume V95% and/or nodal clinical target volume V90% were less than 95% in 17 photon therapy plans and none of the proton plans. Median NTCP of radiation dermatitis ≥ grade 2 was 18.3% (range, 5.4-41.7) with photon therapy and 58.4% (range, 31.4-69.7) with proton therapy. Median excess absolute risk (EAR) of secondary lung cancer at age 80 for current and former smokers was 4.8% (range, 0.0-17.0) using photons and 2.7% (range, 0.0-13.6) using protons. Median EAR of coronary event at age 80, assuming all patients have preexisting cardiac risk factors, was 1.0% (range, 0.0-5.6) with photons and 0.2% (range, 0.0-1.3) with protons. CONCLUSION: Proton therapy plans improved target coverage and reduced risk of coronary artery event and secondary lung cancer while increasing the risk of radiation dermatitis.Rights/Terms
©Copyright 2021 The Author(s).Keyword
bilateral breast cancerbioeffect modeling
normal tissue complication probability
proton therapy
treatment planning
Identifier to cite or link to this item
http://hdl.handle.net/10713/18805ae974a485f413a2113503eed53cd6c53
10.14338/IJPT-21-00023.1