Dataset Information

Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

ABSTRACT: PURPOSE:This work proposes a theoretical framework that enables comparative risk predictions for second cancer incidence after particle beam therapy for different ion species for individual patients, accounting for differences in relative biological effectiveness (RBE) for the competing processes of tumor initiation and cell inactivation. Our working hypothesis was that use of carbon-ion therapy instead of proton therapy would show a difference in the predicted risk of second cancer incidence in the breast for a sample of Hodgkin lymphoma (HL) patients. METHODS AND MATERIALS:We generated biologic treatment plans and calculated relative predicted risks of second cancer in the breast by using two proposed methods: a full model derived from the linear quadratic model and a simpler linear-no-threshold model. RESULTS:For our reference calculation, we found the predicted risk of breast cancer incidence for carbon-ion plans-to-proton plan ratio, , to be 0.75 ± 0.07 but not significantly smaller than 1 (P=.180). CONCLUSIONS:Our findings suggest that second cancer risks are, on average, comparable between proton therapy and carbon-ion therapy.

SUBMITTER: Eley JG

PROVIDER: S-EPMC4844193 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

Eley John G JG Friedrich Thomas T Homann Kenneth L KL Howell Rebecca M RM Scholz Michael M Durante Marco M Newhauser Wayne D WD

International journal of radiation oncology, biology, physics 20160216 1

<h4>Purpose</h4>This work proposes a theoretical framework that enables comparative risk predictions for second cancer incidence after particle beam therapy for different ion species for individual patients, accounting for differences in relative biological effectiveness (RBE) for the competing processes of tumor initiation and cell inactivation. Our working hypothesis was that use of carbon-ion therapy instead of proton therapy would show a difference in the predicted risk of second cancer inci ...[more]

PMID: 27084647

Similar Datasets

Project description:To compare the efficacy and toxicity of adjuvant proton beam vs. carbon-ion beam radiotherapy for head and neck cancers after radical resection and to explore the value of particle beam radiotherapy (PBRT) in postoperative radiotherapy for head and neck cancers. Data from 38 head and neck cancer patients who received adjuvant PBRT after complete surgical resection at the Shanghai Proton and Heavy Ion Center (SPHIC) between October 2015 and March 2019 were retrospectively analyzed. In total, 18 patients received adjuvant proton beam therapy (54-60 GyE/27-30 fractions) and 20 received adjuvant carbon-ion radiotherapy (CIRT) (54-60 GyE/18-20 fractions). Survival rates were calculated using Kaplan-Meier analysis. Toxicity was evaluated according to the Common Terminology Criteria for Adverse Effects (version 4.03). With a median follow-up time of 21 (range, 3-45) months, the 2-year overall survival (OS), progression-free survival (PFS), local-regional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) rates were 93.3%, 87.4%, 94.1%, and 90.7%, respectively, for the entire cohort. The rates after proton beam therapy vs. CIRT were 94.1% vs. 91.7% (P=0.96), 88.1% vs. 86.2% (P=0.96), 94.4% vs. 93.3% (P=0.97), and 88.1% vs. 92.9% (P=0.57), respectively. Furthermore, 16 of the 18 (88.9%) patients developed acute grade I/II dermatitis (13 grade I; 3 grade II) after proton beam therapy, and only 7 of the 20 (35%) patients developed acute grade I dermatitis after CIRT (P=0.001). The incidence of acute grade I/II mucositis and xerostomia in proton and carbon ion cases were 45% vs. 55% (P=0.75) and 56% vs. 50% (P=0.87) respectively. Adjuvant proton beam therapy and CIRT after radical surgical resection for head and neck cancers provided satisfactory therapeutic effectiveness, but no significant difference was observed between the two radiotherapy technologies. However, adjuvant CIRT was associated with a more favorable acute toxicity profile as compared to proton beam therapy with significantly lower frequency and severity of acute dermatitis observed.

Project description:Chordomas are relatively rare lesions of the bones. About 30% occur in the sacrococcygeal region. Surgical resection is still the standard treatment. Due to the size, proximity to neurovascular structures and the complex anatomy of the pelvis, a complete resection with adequate safety margin is difficult to perform. A radical resection with safety margins often leads to the loss of bladder and rectal function as well as motoric/sensoric dysfunction. The recurrence rate after surgery alone is comparatively high, such that adjuvant radiation therapy is very important for improving local control rates. Proton therapy is still the international standard in the treatment of chordomas. High-LET beams such as carbon ions theoretically offer biologic advantages in slow-growing tumors. Data of a Japanese study of patients with unresectable sacral chordoma showed comparable high control rates after hypofractionated carbon ion therapy only.This clinical study is a prospective randomized, monocentric phase II trial. Patients with histologically confirmed sacrococcygeal chordoma will be randomized to either proton or carbon ion radiation therapy stratified regarding the clinical target volume. Target volume delineation will be carried out based on CT and MRI data. In each arm the PTV will receive 64 GyE in 16 fractions. The primary objective of this trial is safety and feasibility of hypofractionated irradiation in patients with sacrococygeal chordoma using protons or carbon ions in raster scan technique for primary or additive treatment after R2 resection. The evaluation is therefore based on the proportion of treatments without Grade 3-5 toxicity (CTCAE, version 4.0) up to 12 months after treatment and/or discontinuation of the treatment for any reason as primary endpoint. Local-progression free survival, overall survival and quality of life will be analyzed as secondary end points.The aim of this study is to confirm the toxicity results of the Japanese data in raster scan technique and to compare it with the toxicity analysis of proton therapy given in the same fractionation. Using this data, a further randomized phase III trial is planned, comparing hypofractionated proton and carbon ion irradiation.ClinicalTrials.gov Identifier: NCT01811394.

Project description:Pretreatment computed tomography (CT) imaging is an essential component of the particle therapy treatment planning chain. Treatment planning and optimization with charged particles require accurate and precise estimations of ion beam range in tissues, characterized by the stopping power ratio (SPR). Reduction of range uncertainties arising from conventional CT-number-to-SPR conversion based on single-energy CT (SECT) imaging is of importance for improving clinical practice. Here, the application of a novel imaging and computational methodology using dual-layer spectral CT (DLCT) was performed toward refining patient-specific SPR estimates. A workflow for DLCT-based treatment planning was devised to evaluate SPR prediction for proton, helium, and carbon ion beam therapy planning in the brain. DLCT- and SECT-based SPR predictions were compared in homogeneous and heterogeneous anatomical regions. This study included eight patients scanned for diagnostic purposes with a DLCT scanner. For each patient, four different treatment plans were created, simulating tumors in different parts of the brain. For homogeneous anatomical regions, mean SPR differences of about 1% between the DLCT- and SECT-based approaches were found. In plans of heterogeneous anatomies, relative (absolute) proton range shifts of 0.6% (0.4 mm) in the mean and up to 4.4% (2.1 mm) at the distal fall-off were observed. In the investigated cohort, 12% of the evaluated organs-at-risk (OARs) presented differences in mean or maximum dose of more than 0.5 Gy (RBE) and up to 6.8 Gy (RBE) over the entire treatment. Range shifts and dose differences in OARs between DLCT and SECT in helium and carbon ion treatment plans were similar to protons. In the majority of investigated cases (75th percentile), SECT- and DLCT-based range estimations were within 0.6 mm. Nonetheless, the magnitude of patient-specific range deviations between SECT and DLCT was clinically relevant in heterogeneous anatomical sites, suggesting further study in larger, more diverse cohorts. Results indicate that patients with brain tumors may benefit from DLCT-based treatment planning.

Dataset Information

Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

Publications

Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets