Epworth Radiation Oncology

Transcription

1 Epworth HealthCare Epworth Radiation Oncology Intensity-Modulated Radiotherapy versus Three- Dimensional Conformal Radiotherapy; a retrospective study Emma Fitzgerald

2 Overview Literature search into Breast Intensity-Modulated Radiation Therapy (IMRT) Challenging Planning Target Volumes (PTV) Breast IMRT solution Critical review of technique Identify the clinical indicators Future direction of technique

3 History Radiation Therapy remains integral to the management of Breast Cancer (1-6) Dosimetric Improvements from Two-Dimensional to Three-Dimensional Conformal Radiation Therapy (3DCRT) Are further improvements possible? Does IMRT have a role to play? If so, what are the indicators?

4 Literature Breast IMRT Retrospective studies question feasibility (1-3, 6, 8, 9, 10, 11) Positives Improved Homogeneity Better PTV conformity index Ipsilateral Lung V20 Gy Integral Dose Negatives Heart Mean Dose Contralateral Breast Dose Increased trend to use IMRT for breast but no detailed specific clinical scenarios (Lisa, A 2011) IMRT is dependent upon technique (2, 6-7, 12)

5 Clinical Example Comparison of 2 different IMRT plans 6 FLDs Tan Approach Vs 9 FLDs ~30⁰ apart

6 Background Field-In-Field PTV based approach is standard Acknowledge IMRT is resource intensive Limited benefit to replace as standard (11) However, real role to specific clinical scenarios (7, 9, 13, 10) Internal Mammary Chain (IMC) Complex volumes close to Organs At Risk (OARs)

7 PTV & OAR

8 PTV & OAR

9 PTV & OAR Right Coronary Artery (RCA) Planning Risk Volume (PRV)

10 PTV & OAR 4.2cm

11 PTV & OAR Left Anterior Descending (LAD) Coronary Artery Delineation

12 The Clinical Decision Radiation Oncologist Driven Higher concern for IMC recurrence than Chronic toxicity LAD dose <30 Gy (14) RCA dose <35 Gy Application of Evidence Based Dose Constraints (14, 16) Extensive IMRT planning and treatment experience Collaboration with other sites

13 Method 9 field Beam Arrangement:

14 Method Supraclavicular Fossa (SCF) and Axilla Beam Arrangement:

15 Method SCF/Axilla Beam Arrangement:

16 Method Target Structures for IMRT Optimisation:

17 Method Target Structures for IMRT Optimisation:

18 Method Target Structures for IMRT Optimisation:

19 Method Target Structures for IMRT Optimisation:

20 Method 3DCRT - Wide Field Tangents & SCF/Axilla:

21 Results Isodose Range 47.5 Gy IMRT Vs 3DCRT

22 Results Isodose Range 47.5 Gy IMRT Vs 3DCRT

23 Results Isodose Range 25 Gy IMRT Vs 3DCRT

24 Results Isodose Range 5 Gy IMRT Vs 3DCRT

25 Results Dose Volume Comparison IMRT Vs 3DCRT IMRT (Gy) 3DCRT (Gy) Goal (Gy) PTV D 98% PTV D 2 % Right Lung V < 15% (7.5) Heart Mean < 5 Heart Max < 50 PRV RCA Max < 35 LAD N/A N/A < 30 Max Brachial Plexus < 52 Max Contra Breast Max < 5 *** Contra Lung Mean < 5

26 Results Dose Volume Comparison IMRT Vs 3DCRT IMRT (Gy) 3DCRT (Gy) Goal (Gy) PTV D 98% PTV D 2 % Right Lung V < 15% (7.5) Heart Mean < 5 Heart Max < 50 PRV RCA Max < 35 LAD N/A N/A < 30 Max Brachial Plexus < 52 Max Contra Breast Max < 5 *** Contra Lung Mean < 5

27 Discussion PTV depth to cover IMC is a challenge IMRT advantages over 3DCRT; Improved Conformity of dose to PTV Lower dose to most OARs. IMRT disadvantages over 3DCRT; Increased mean dose to heart and contralat lung Higher integral dose Accurate delineation of OAR required Pre & Post Contrast CT for LAD (RO)

28 Discussion Limitations of this study Comparison of only one 3DCRT approach???junctional electron technique Future Direction 11 patients treated with IMRT for breast cancer to date RapidArc and Respiratory Gating IGRT match results trend review Clinical use of breast drapes

29 Conclusion IMRT improves PTV coverage IMRT reduces OAR dose at expense of higher integral dose Wide field 3DCRT cannot achieve comparable results Careful selection of suitable cases is recommended IMRT has become the standard of care for complex breast cancer cases

30 Acknowledgements Jim Frantzis Paul Fenton Professor Chris Hamilton Robert Lumsden Staff at Epworth Radiation Oncology

31 References 1. Hurkmans W, Cho B, Damen E, Zijp L, Mijnheer B. Reduction of cardiac and lung complication probabilities after breast irradiation using conformal radiotherapy with or without intensity modulation. J of Radiotherapy & Oncology 2002; 62: Landau D, Adams E, Webb S, Ross G. Cardiac avoidance in breast radiotherapy: a comparison of simple shielding techniques with intensitymodulated radiotherapy. J of Radiotherapy & Oncology 2001; 60: Lohr F, El-Haddad M, Dobler B, Grau R, Wertz H-J, Kraus-Tiefenbacher U, Steil V, Madyan Y, Wenz F. Potential effect of robust and simple IMRT approach for left-sided breast cancer on cardiac mortality. Int. J Radiation Oncology Biol. Phys. 2008; 74: Meei The A, Walsh L, Purdie T, Mosseri A, Xu W, Levin W, Koch C, Fyles A, Liu F-F, Cho B. Concomitant intensity modulated boost during whole breast hypofractionated radiotherapy A feasibiity and toxicity study. J of Radiotherapy & Onocology 2012; 102: Toscas J, Linero D, Rubio I, Hidalgo A, Arnalte R, Escude L, Cozzi L, Fogliata A, Miralbell R. Boosting the tumor bed from deep-seated tumors in early-stage breast cancer: A planning study between electron, photon and proton beams. J of Radiotherapy & Oncology 2010; 96: Stille A, Kron T, Herschtal A, Hornby C, Cramb J, Sullivan K, Chua B. Does inverse-planned intenstiy-modulated radiation therapy have a role in the treatment of patients with left-sided breast cancer? J of Medical Imaging and Radiation Oncology 2011; 55: Beckham W, Popescu C, Patenaude V, Wai E, Olivotto I. Is multibeam IMRT better than standard treatment for patients with left-sided breast cancer? Int. J. Radiation Oncology Biol. Phys. 2007; 69:

32 References 8. Abeyaratne D. Can intensity modulated radiation therapy reduce cardiac dose in left-sided breast patients? The Radiographer 2010; 57: Thilmann C, Sroka-Perez G, Krempien R, Hoess A, Wannenmacher M, Debus J. Inversely planned intensity modulated radiotherapy of the breast including the internal mammary chain: a plan comparison study. Technol Cancer Res Treat 2004; 3: Dogan N. Cuttino L. Lloyd R. Bump E. Arthur D. Optimized Dose Coverage of Regional Lymph Nodes in Breast Cancer: The Role of Intensity- Modulated Radiotherapy. Int. J. of Radiation Oncology Biol. Phys. 2007; 68: Dayes I, Rumble R, Bowen J, Dixon P, Warde P. Intensity-Modulated Radiotherapy in the Treatment of Breast Cancer. Clinical Oncology 2012; 24: Jagsi R, Moran J, Marsh R, Masi K, Griffith K, Pierce L. Evaluation of Four Techniques Using Intensity-Modualted Radiation Therapy for Comprehensive Locoregional Irradiation of Breast Cancer. Int. J of Radiation Oncology Biol. Phys. 2010; 78: Jin JY, Klein EE, Kong FM, Li Z. An improved internal mammary irradiation technique in radiation treatment of locally advanced breast cancers. J Appl Clin Med Phys 2005; 6: Taylor C, Povall J. McGale P. Nisbet A. Dodwell D. Smith J. Darby S. Cardiac Dose From Tangential Breast Cancer Radiotherapy in the year Int. J. of Radiation Oncology. Biol. Phys. 2008; 72: Louise Richter. Dose to the LAD associated with 3DCRT vs IMRT for Left sided breast irradiation. Powerpoint Presentation ICRU 83 Report.

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