The effect of delineation method and observer variability on bladder dose-volume histograms for prostate intensity modulated radiotherapy

AbstractBackgroundWe demonstrated that our proposed planning target volume (PTV) dose–volume factor (PDVF) can be used to evaluate the PTV dose coverage between the intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans based on 90 prostate patients.PurposePDVF were determined from the prostate IMRT and VMAT plans to compare their variation of PTV dose coverage. Comparisons of the PDVF with other plan evaluation parameters such as D5%, D95%, D99%, Dmean, conformity index (CI), homogeneity index (HI), gradient index (GI) and prostate tumour control probability (TCP) were carried out.Methods and materialsProstate IMRT and VMAT plans using the 6 MV photon beams were created from 40 and 50 patients, respectively. Dosimetric indices (CI, HI and GI), dose–volume points (D5%, D95%, D99% and Dmean) and prostate TCP were calculated according to the PTV dose–volume histograms (DVHs) of the plans. All PTV DVH curves were fitted using the Gaussian error function (GEF) model. The PDVF were calculated based on the GEF parameters.ResultsFrom the PTV DVHs of the prostate IMRT and VMAT plans, the average D99% of the PTV for IMRT and VMAT were 74·1 and 74·5 Gy, respectively. The average prostate TCP were 0·956 and 0·958 for the IMRT and VMAT plans, respectively. The average PDVF of the IMRT and VMAT plans were 0·970 and 0·983, respectively. Although both the IMRT and VMAT plans showed very similar prostate TCP, the dosimetric and radiobiological results of the VMAT technique were slightly better than IMRT.ConclusionThe calculated PDVF for the prostate IMRT and VMAT plans agreed well with other dosimetric and radiobiological parameters in this study. PDVF was verified as an alternative of evaluation parameter in the quality assurance of prostate treatment planning.

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Predictors of Mastoiditis after Intensity-Modulated Radiotherapy in Nasopharyngeal Carcinoma: A Dose-Volume Analysis

Journal of Cancer ◽

10.7150/jca.13183 ◽

2016 ◽

Vol 7 (3) ◽

pp. 276-282 ◽

Cited By ~ 1

Author(s):

Ji-Jin Yao ◽

Guan-Qun Zhou ◽

Ya-Nan Jin ◽

Wang-Jian Zhang ◽

Li Lin ◽

...

Keyword(s):

Nasopharyngeal Carcinoma ◽

Intensity Modulated Radiotherapy ◽

Volume Analysis ◽

Intensity Modulated ◽

Dose Volume

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Incidental Dose to Pelvic Nodal Regions in Prostate-Only Radiotherapy

Technology in Cancer Research & Treatment ◽

10.1177/1533034616661447 ◽

2016 ◽

Vol 16 (2) ◽

pp. 211-217 ◽

Cited By ~ 3

Author(s):

Vedang Murthy ◽

Shirley Lewis ◽

Mayur Sawant ◽

Siji N. Paul ◽

Umesh Mahantshetty ◽

...

Keyword(s):

Intensity Modulated Radiotherapy ◽

Conventional Radiotherapy ◽

Prostate Radiotherapy ◽

3 Dimensional ◽

Intensity Modulated ◽

Treatment Techniques ◽

Dose Volume ◽

Internal Iliac ◽

The Mean ◽

Conformal Treatment

Objectives: Pelvic lymph nodal regions receive an incidental dose from conformal treatment of the prostate. This study was conducted to investigate the doses received by the different pelvic nodal regions with varying techniques used for prostate radiotherapy. Methods and Materials: Twenty patients of high-risk node-negative prostate cancer treated with intensity-modulated radiotherapy to the prostate alone were studied. Replanning was done for intensity-modulated radiotherapy, 3-dimensional conformal treatment, and 2-dimensional conventional radiotherapy with additional delineation of the pelvic nodal regions, namely, common iliac (upper and lower), presacral, internal iliac, obturator, and external iliac. Dose–volume parameters such as Dmean, D100%, D66%, D33%, V40, and V50 to each of the nodal regions were estimated for all patients. Results: The obturator nodes received the highest dose among all nodal regions. The mean dose received by obturator nodal region was 44, 29, and 22 Gy from 2-dimensional conventional radiotherapy, 3-dimensional conformal treatment, and intensity-modulated radiotherapy, respectively. The mean dose was significantly higher when compared between 2-dimensional conventional radiotherapy and 3-dimensional conformal treatment ( P < .001), 2-dimensional conventional radiotherapy and intensity-modulated radiotherapy ( P < .001), and 3-dimensional conformal treatment and intensity-modulated radiotherapy ( P < .001). The D33% of the obturator region was 64, 39, and 37 Gy from 2-dimensional conventional radiotherapy, 3-dimensional conformal treatment, and intensity-modulated radiotherapy, respectively. The dose received by all other pelvic nodal regions was low and not clinically relevant. Conclusion: The incidental dose received by obturator regions is significant especially with 2-dimensional conventional radiotherapy and 3-dimensional conformal treatment techniques as used in the trials studying elective pelvic nodal irradiation. However, with intensity-modulated radiotherapy, this dose is lower, making elective pelvic irradiation more relevant. Advances in Knowledge: This study highlights that incidental dose received by obturator regions is significant especially with 2-dimensional conventional radiotherapy and 3-dimensional conformal treatment techniques.

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Intensity-modulated Radiotherapy for Anal Cancer: Dose–Volume Relationship of Acute Gastrointestinal Toxicity and Disease Outcomes

Clinical Oncology ◽

10.1016/j.clon.2018.07.020 ◽

2018 ◽

Vol 30 (10) ◽

pp. 634-641 ◽

Cited By ~ 6

Author(s):

M. Ng ◽

H. Ho ◽

J. Skelton ◽

M. Guerrieri ◽

M. Guiney ◽

...

Keyword(s):

Anal Cancer ◽

Intensity Modulated Radiotherapy ◽

Gastrointestinal Toxicity ◽

Intensity Modulated ◽

Disease Outcomes ◽

Dose Volume ◽

Volume Relationship ◽

Relationship Of

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Cardiac radiation dose predicts survival in esophageal squamous cell carcinoma treated by definitive concurrent chemotherapy and intensity modulated radiotherapy

Radiation Oncology ◽

10.1186/s13014-020-01664-7 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Tzu-Hui Pao ◽

Wei-Lun Chang ◽

Nai-Jung Chiang ◽

Jeffrey Shu-Ming Chang ◽

Chia-Ying Lin ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Radiation Dose ◽

Adverse Events ◽

Esophageal Squamous Cell Carcinoma ◽

Cumulative Incidence ◽

Prognostic Significance ◽

Intensity Modulated Radiotherapy ◽

Intensity Modulated ◽

Dose Volume ◽

Cardiac Dose

Abstract Background The prognostic significance of cardiac radiation dose in esophageal cancer after definitive concurrent chemoradiotherapy (CCRT) remains largely unknown. We aimed to investigate the association between cardiac dose-volume parameters and overall survival (OS) in esophageal squamous cell carcinoma (ESCC) after definitive CCRT. Methods One hundred and twenty-one ESCC patients undergoing definitive CCRT with intensity modulated radiotherapy technique between 2008 and 2018 were reviewed. Cardiac dose-volume parameters were calculated. Survival of patients and cumulative incidence of adverse events were estimated by the Kaplan–Meier method and compared between groups by the log-rank test. The prognostic significance of cardiac dose-volume parameters was determined with multivariate Cox proportional hazards regression analysis. Results Median follow-up was 16.2 months (range, 4.3–109.3). Median OS was 18.4 months. Heart V5, V10, and V20 were independent prognostic factors of OS. Median OS was longer for patients with heart V5 ≤ 94.3% (24.7 vs. 16.3 months, p = 0.0025), heart V10 ≤ 86.4% (24.8 vs. 16.9 months, p = 0.0041), and heart V20 ≤ 76.9% (20.0 vs. 17.2 months, p = 0.047). Lower cumulative incidence of symptomatic cardiac adverse events was observed among patients with heart V5 ≤ 94.3% (p = 0.017), heart V10 ≤ 86.4% (p = 0.02), and heart V20 ≤ 76.9% (p = 0.0057). Patients without symptomatic cardiac adverse events had a higher 3-year OS rate (33.8% vs. 0%, p = 0.03). Conclusions Cardiac radiation dose inversely correlated with survival in ESCC after definitive CCRT. Radiation dose to the heart should be minimized.

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