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Lafond C, Barateau A, N'Guessan J, Perichon N, Delaby N, Simon A, Haigron P, Mylona E, Acosta O, de Crevoisier R. Planning With Patient-Specific Rectal Sub-Region Constraints Decreases Probability of Toxicity in Prostate Cancer Radiotherapy. Front Oncol 2020; 10:1597. [PMID: 33042802 PMCID: PMC7517942 DOI: 10.3389/fonc.2020.01597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 07/23/2020] [Indexed: 11/27/2022] Open
Abstract
Background: A rectal sub-region (SRR) has been previously identified by voxel-wise analysis in the inferior-anterior part of the rectum as highly predictive of rectal bleeding (RB) in prostate cancer radiotherapy. Translating the SRR to patient-specific radiotherapy planning is challenging as new constraints have to be defined. A recent geometry-based model proposed to optimize the planning by determining the achievable mean doses (AMDs) to the organs at risk (OARs), taking into account the overlap between the planning target volume (PTV) and OAR. The aim of this study was to quantify the SRR dose sparing by using the AMD model in the planning, while preserving the dose to the prostate. Material and Methods: Three-dimensional volumetric modulated arc therapy (VMAT) planning dose distributions for 60 patients were computed following four different strategies, delivering 78 Gy to the prostate, while meeting the genitourinary group dose constraints to the OAR: (i) a standard plan corresponding to the standard practice for rectum sparing (STDpl), (ii) a plan adding constraints to SRR (SRRpl), (iii) a plan using the AMD model applied to the rectum only (AMD_RECTpl), and (iv) a final plan using the AMD model applied to both the rectum and the SRR (AMD_RECT_SRRpl). After PTV dose normalization, plans were compared with regard to dose distributions, quality, and estimated risk of RB using a normal tissue complication probability model. Results: AMD_RECT_SRRpl showed the largest SRR dose sparing, with significant mean dose reductions of 7.7, 3, and 2.3 Gy, with respect to the STDpl, SRRpl, and AMD_RECTpl, respectively. AMD_RECT_SRRpl also decreased the mean rectal dose by 3.6 Gy relative to STDpl and by 3.3 Gy relative to SRRpl. The absolute risk of grade ≥1 RB decreased from 22.8% using STDpl planning to 17.6% using AMD_RECT_SRRpl considering SRR volume. AMD_RECT_SRRpl plans, however, showed slightly less dose homogeneity and significant increase of the number of monitor units, compared to the three other strategies. Conclusion: Compared to a standard prostate planning, applying dose constraints to a patient-specific SRR by using the achievable mean dose model decreased the mean dose by 7.7 Gy to the SRR and may decrease the relative risk of RB by 22%.
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Affiliation(s)
- Caroline Lafond
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Anaïs Barateau
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Joël N'Guessan
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Nicolas Perichon
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Nolwenn Delaby
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Antoine Simon
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Pascal Haigron
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Eugenia Mylona
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Oscar Acosta
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
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Freeman AR, Roos DE, Kim L. Quality indicators for prostate radiotherapy: are patients disadvantaged by receiving treatment in a 'generalist' centre? J Med Imaging Radiat Oncol 2014; 59:255-64. [PMID: 25345594 DOI: 10.1111/1754-9485.12252] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 09/06/2014] [Indexed: 11/30/2022]
Abstract
INTRODUCTION The purpose of this retrospective review was to evaluate concordance with evidence-based quality indicator guidelines for prostate cancer patients treated radically in a 'generalist' (as distinct from 'sub-specialist') centre. We were concerned that the quality of treatment may be lower in a generalist centre. If so, the findings could have relevance for many radiotherapy departments that treat prostate cancer. METHODS Two hundred fifteen consecutive patients received external beam radiotherapy (EBRT) and/or brachytherapy between 1.10.11 and 30.9.12. Treatment was deemed to be in line with evidence-based guidelines if the dose was: (i) 73.8-81 Gy at 1.8-2.0 Gy/fraction for EBRT alone (eviQ guidelines); (ii) 40-50 Gy (EBRT) for EBRT plus high-dose rate (HDR) brachytherapy boost (National Comprehensive Cancer Network (NCCN) guidelines); and (iii) 145 Gy for low dose rate (LDR) I-125 monotherapy (NCCN). Additionally, EBRT beam energy should be ≥6 MV using three-dimensional conformal RT (3D-CRT) or intensity-modulated RT (IMRT), and high-risk patients should receive neo-adjuvant androgen-deprivation therapy (ADT) (eviQ/NCCN). Treatment of pelvic nodes was also assessed. RESULTS One hundred four high-risk, 84 intermediate-risk and 27 low-risk patients (NCCN criteria) were managed by eight of nine radiation oncologists. Concordance with guideline doses was confirmed in: (i) 125 of 136 patients (92%) treated with EBRT alone; (ii) 32 of 34 patients (94%) treated with EBRT + HDR BRT boost; and (iii) 45 of 45 patients (100%) treated with LDR BRT alone. All EBRT patients were treated with ≥6 MV beams using 3D-CRT (78%) or IMRT (22%). 84%, 21% and 0% of high-risk, intermediate-risk and low-risk patients received ADT, respectively. Overall treatment modality choice (including ADT use and duration where assessable) was concordant with guidelines for 176/207 (85%) of patients. CONCLUSION The vast majority of patients were treated concordant with evidence-based guidelines suggesting that, within the limits of the selected criteria, prostate cancer patients are unlikely to be disadvantaged by receiving radiotherapy in this 'generalist' centre.
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Park YK, Park S, Wu HG, Kim S. A new plan quality index for dose painting radiotherapy. J Appl Clin Med Phys 2014; 15:4941. [PMID: 25207424 PMCID: PMC5875497 DOI: 10.1120/jacmp.v15i4.4941] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/09/2014] [Accepted: 03/31/2014] [Indexed: 12/02/2022] Open
Abstract
Dose painting radiotherapy is considered a promising radiotherapy technology that enables more targeted dose delivery to tumor rich regions while saving critical normal tissues. Obviously, dose painting planning would be more complicated and hard to be evaluated with current plan quality index systems that were developed under the paradigm of uniform dose prescription. In this study, we introduce a new plan quality index, named “index of achievement (IOA)” that assesses how close the planned dose distribution is to the prescribed one in a dose painting radiotherapy plan. By using voxel‐based comparison between planned and prescribed dose distributions in its formulation, the index allows for a single‐value evaluation regardless of the number of prescribed dose levels, which cannot be achieved with the conventional indices such as conventional homogeneity index. Benchmark calculations using patient data demonstrated feasibility of the index not only for contour‐based dose painting plans, but also for dose painting by numbers plans. Also, it was shown that there is strong correlation between the new index and conventional indices, which indicates a potential of the new index as an alternative to conventional ones in general radiotherapy plan evaluation. PACS number: 87.55.D‐
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Healy B, Frantzis J, Murry R, Martin J, Plank A, Middleton M, Catton C, Kron T. Results from a multicenter prostate IMRT dosimetry intercomparison for an OCOG-TROG clinical trial. Med Phys 2014; 40:071706. [PMID: 23822410 DOI: 10.1118/1.4808151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE A multi-institution dosimetry intercomparison has been undertaken of prostate intensity modulated radiation therapy (IMRT) delivery. The dosimetry intercomparison was incorporated into the quality assurance for site credentialing for the Trans-Tasman Radiation Oncology Group Prostate Fractionated Irradiation Trial 08.01 clinical trial. METHODS An anthropomorphic pelvic phantom with realistic anatomy was used along with multiplanar dosimetry tools for the assessment. Nineteen centers across Australia and New Zealand participated in the study. RESULTS In comparing planned versus measured dose to the target at the isocenter within the phantom, all centers were able to achieve a total delivered dose within 3% of planned dose. In multiplanar analysis with radiochromic film using the gamma analysis method to compare delivered and planned dose, pass rates for a 5%/3 mm criterion were better than 90% for a coronal slice through the isocenter. Pass rates for an off-axis coronal slice were also better than 90% except for one instance with 84% pass rate. CONCLUSIONS Strengths of the dosimetry assessment procedure included the true anthropomorphic nature of the phantom used, the involvement of an expert from the reference center in carrying out the assessment at every site, and the ability of the assessment to detect and resolve dosimetry discrepancies.
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Affiliation(s)
- B Healy
- Radiation Oncology Queensland, Toowoomba, Queensland 4350, Australia.
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Albert JM, Das P. Quality indicators in radiation oncology. Int J Radiat Oncol Biol Phys 2012; 85:904-11. [PMID: 23040217 DOI: 10.1016/j.ijrobp.2012.08.038] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 08/28/2012] [Accepted: 08/29/2012] [Indexed: 11/28/2022]
Abstract
Oncologic specialty societies and multidisciplinary collaborative groups have dedicated considerable effort to developing evidence-based quality indicators (QIs) to facilitate quality improvement, accreditation, benchmarking, reimbursement, maintenance of certification, and regulatory reporting. In particular, the field of radiation oncology has a long history of organized quality assessment efforts and continues to work toward developing consensus quality standards in the face of continually evolving technologies and standards of care. This report provides a comprehensive review of the current state of quality assessment in radiation oncology. Specifically, this report highlights implications of the healthcare quality movement for radiation oncology and reviews existing efforts to define and measure quality in the field, with focus on dimensions of quality specific to radiation oncology within the "big picture" of oncologic quality assessment efforts.
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Affiliation(s)
- Jeffrey M Albert
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Batumalai V, Jameson MG, Forstner DF, Vial P, Holloway LC. How important is dosimetrist experience for intensity modulated radiation therapy? A comparative analysis of a head and neck case. Pract Radiat Oncol 2012; 3:e99-e106. [PMID: 24674377 DOI: 10.1016/j.prro.2012.06.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 06/04/2012] [Accepted: 06/22/2012] [Indexed: 02/07/2023]
Abstract
PURPOSE Treatment planning for IMRT is a complex process that requires additional training and expertise. The aim of this study was to compare and analyze IMRT plans generated by dosimetrists with varying levels of IMRT planning experience. METHODS AND MATERIALS The computed tomography (CT) data of a patient previously treated with IMRT for left tonsillar carcinoma were used. The patient's preexisting planning target volumes (PTVs) and all organs at risk were provided with the CT data set. Six dosimetrists with variable IMRT planning experience generated IMRT plans according to the department's protocol. Plan analysis included visual inspection and comparison of dose-volume histogram, conformity indices, treatment delivery efficiency, and dose delivery accuracy. RESULTS Visual review of the dose distribution showed that the 6 plans were comparable. However, only the 2 most experienced dosimetrists were able to meet the strict PTV aims and critical structure constraints. The least experienced dosimetrist had the worst planning outcome. Comparison of delivery efficiency showed that the number of segments, total monitor units, and treatment time increased as the IMRT planning experience decreased. CONCLUSIONS Dosimetrists with higher levels of IMRT planning experience produced a better quality head and neck IMRT plan. Different planning experience may need to be considered when organizing appropriate departmental resources.
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Affiliation(s)
- Vikneswary Batumalai
- Cancer Therapy Centre, Liverpool Hospital, Sydney, Australia; University of New South Wales, NSW, Australia.
| | - Michael G Jameson
- Cancer Therapy Centre, Liverpool Hospital, Sydney, Australia; Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - Dion F Forstner
- Cancer Therapy Centre, Liverpool Hospital, Sydney, Australia; Collaboration of Cancer Outcome Research and Evaluation (CCORE), Liverpool Hospital, Sydney, Australia
| | - Philip Vial
- Cancer Therapy Centre, Liverpool Hospital, Sydney, Australia; Institute of Medical Physics, School of Medical Physics, University of Sydney, Sydney, Australia
| | - Lois C Holloway
- Cancer Therapy Centre, Liverpool Hospital, Sydney, Australia; University of New South Wales, NSW, Australia; Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia; Institute of Medical Physics, School of Medical Physics, University of Sydney, Sydney, Australia
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Pahlajani N, Ruth KJ, Buyyounouski MK, Chen DYT, Horwitz EM, Hanks GE, Price RA, Pollack A. Radiotherapy doses of 80 Gy and higher are associated with lower mortality in men with Gleason score 8 to 10 prostate cancer. Int J Radiat Oncol Biol Phys 2012; 82:1949-56. [PMID: 21763081 PMCID: PMC3827957 DOI: 10.1016/j.ijrobp.2011.04.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 03/30/2011] [Accepted: 04/06/2011] [Indexed: 11/12/2022]
Abstract
PURPOSE Men with Gleason score (GS) 8-10 prostate cancer (PCa) are assumed to have a high risk of micrometastatic disease at presentation. However, local failure is also a major problem. We sought to establish the importance of more aggressive local radiotherapy (RT) to ≥80 Gy. METHODS AND MATERIALS There were 226 men treated consecutively with RT ± ADT from 1988 to 2002 for GS 8-10 PCa. Conventional, three-dimensional conformal or intensity-modulated (IM) RT was used. Radiation dose was divided into three groups: (1) <75 Gy (n = 50); (2) 75-79.9 Gy (n = 60); or (3) ≥80 Gy (n = 116). The endpoints examined included biochemical failure (BF; nadir + 2 definition), distant metastasis (DM), cause-specific mortality, and overall mortality (OM). RESULTS Median follow-up was 66, 71, and 58 months for Groups 1, 2, and 3. On Fine and Gray's competing risk regression analysis, significant predictors of reduced BF were RT dose ≥80 Gy (p = 0.011) and androgen deprivation therapy duration ≥24 months (p = 0.033). In a similar model of DM, only RT dose ≥80 Gy was significant (p = 0.007). On Cox regression analysis, significant predictors of reduced OM were RT dose ≥80 Gy (p = 0.035) and T category (T3/4 vs. T1, p = 0.041). Dose was not a significant determinant of cause-specific mortality. Results for RT dose were similar in a model with RT dose and ADT duration as continuous variables. CONCLUSION The results indicate that RT dose escalation to ≥80 Gy is associated with lower risks of BF, DM, and OM in men with GS 8-10 PCa, independently of androgen deprivation therapy.
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Affiliation(s)
- Niraj Pahlajani
- Department of Radiation Oncology, Cooper University Hospital, Camden, NJ
| | - Karen J Ruth
- Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA
| | | | - David Y T Chen
- Department of Urology, Fox Chase Cancer Center, Philadelphia, PA
| | - Eric M Horwitz
- Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA
| | - Gerald E. Hanks
- Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA
| | - Robert A. Price
- Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA
| | - Alan Pollack
- Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, FL
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