Intensity modulated radiotherapy versus volumetric modulated arc therapy in breast cancer: A comparative dosimetric analysis

KR Muralidhar, Bhudevi Soubhagya, Shabbir Ahmed

Abstract


Purpose: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) has the capacity to optimize the dose distribution. We analyzed the dosimetric differences of plans in treatment planning system (TPS) between VMAT and IMRT in treating breast cancer.

Methods: Fourteen patients were simulated, planned, and treated with VMAT using single, double or partial arcs. IMRT treatments were generated using 4 to 5 tangential IMRT fields for the same patients. All treatment plans were planned for 50 Gy in 25 fractions. The VMAT and IMRT plans were compared using the planning target volume (PTV) dose and doses to the other organs at risk (OARs).

Results: For the PTV, comparable minimum, mean, maximum, median, and modal dose as well equivalent sphere diameter of the structure (Equis) were observed between VMAT and IMRT plans and found that these values were significantly equal in both techniques. The right lung mean and modal doses were considerably higher in VMAT plans while maximum value was considerably lower when compared with IMRT plans. The left lung mean and modal doses were higher with VMAT while maximum doses were higher in IMRT plans. The mean dose to the heart and maximum dose to the spinal cord was lower with IMRT. The mean dose to the body was higher in VMAT plans while the maximum dose was higher in IMRT plans.

Conclusion: Four field tangential IMRT delivered comparable PTV dose with generally less dose to normal tissues in our breast cancer treatment study. The IMRT plans typically had more favourable dose characteristics to the lung, heart, and spinal cord and body dose when compared with VMAT. The only minor advantage of VMAT for breast cases was slightly better PTV coverage.


Keywords


Breast Cancer; IMRT; VMAT

Full Text:

PDF

References


Hurkmans CW, Borger JH, Bos LJ, et al. Cardiac and lung complication probabilities after breast cancer irradiation. Radiother Oncol 2000; 55:145-51.

Favourable and unfavourable effects on long-term survival of radiotherapy for early breast cancer: an overview of the randomised trials. Early Breast Cancer Trialists' Collaborative Group. Lancet 2000; 355:1757-70.

Potters L, Steinberg M, Wallner P, Hevezi J. How one defines intensity-modulated radiation therapy. Int J Radiat Oncol Biol Phys 2003; 56:609-10.

Glatstein E. The return of the snake oil salesmen. Int J Radiat Oncol Biol Phys 2003; 55:561-2.

Glatstein E. Intensity-modulated radiation therapy: the inverse, the converse, and the perverse. Semin Radiat Oncol 2002; 12:272-81.

Clarke DH, Le MG, Sarrazin D, et al. Analysis of local-regional relapses in patients with early breast cancers treated by excision and radiotherapy: experience of the Institut Gustave-Roussy. Int J Radiat Oncol Biol Phys 1985; 11:137-45.

Kestin LL, Sharpe MB, Frazier RC, et al. Intensity modulation to improve dose uniformity with tangential breast radiotherapy: initial clinical experience. Int J Radiat Oncol Biol Phys 2000; 48:1559-68.

Lo YC, Yasuda G, Fitzgerald TJ, Urie MM. Intensity modulation for breast treatment using static multi-leaf collimators. Int J Radiat Oncol Biol Phys 2000; 46:187-94.

Evans PM, Donovan EM, Partridge M, et al. The delivery of intensity modulated radiotherapy to the breast using multiple static fields. Radiother Oncol 2000; 57:79-89.

Li JG, Williams SS, Goffinet DR, et al. Breast-conserving radiation therapy using combined electron and intensity-modulated radiotherapy technique. Radiother Oncol 2000; 56:65-71.

Zackrisson B, Arevaran M, Karlsson M. Optimized MLC-beam arrangements for tangential breast irradiation. Radiother Oncol 2000; 54:209-212.

Donovan EM, Johnson U, Shentall G, et al. Evaluation of compensation in breast radiotherapy: A planning study sing multiple static fields. Int J Radiat Oncol Biol Phys 2000; 46:671-9.

Chang SX, Deschesne KM, Cullip TJ, et al. A comparison of different intensity modulation treatment techniques for tangential breast irradiation. Int J Radiat Oncol Biol Phys 1999; 45:1305-14.

Smith MC, Li SD, Shostak CA, et al. Breast –conserving radiation therapy: Potential of inverse planning with intensity modulation. Radiology 1997; 203:871-6.

Hansen VN, Evans PM, Shentall GS, et al, Dosimetric evaluation of compensation in radiotherapy of the breast: MLC intensity modulation and physical compensators. Radiother Oncol 1997; 42:249-256.

Hong L, Hunt M, Chui C, et al. Intensity-modulated tangential beam irradiation of the intact breast. Int J Radiat Oncol Biol Phys 1999; 44:1155-64.

Carruther LJ, Redpath AT, Kunkler IH. The use of compensators to optimise the three dimensional dose distribution in radiotherapy of the intact breast. Radiother Oncol 1999; 50:291-300.

Kiricuta IC, Gotz U, Schwab F, et al. Target volume definition and target conformal irradiation technique for breast cancer patients. Acta Oncol 2000; 39:429-36.

Lee B, Lee S, Sung J, Yoon M. Radiotherapy-induced secondary cancer risk for breast cancer: 3D conformal therapy versus IMRT versus VMAT. J Radiol Prot 2014; 34:325-31.

Abo-Madyan Y, Aziz MH, Aly MM, et al. Second cancer risk after 3D-CRT, IMRT and VMAT for breast cancer. Radiother Oncol 2014; 110:471-6.

Jin GH, Chen LX, Deng XW, et al. A comparative dosimetric study for treating left-sided breast cancer for small breast size using five different radiotherapy techniques: conventional tangential field, filed-in-filed, tangential-IMRT, multi-beam IMRT and VMAT. Radiat Oncol 2013; 8:89.

Ashraf M, Janardhan N, Bhavani P, et al. Dosimetric comparison of 3DCRT versus IMRT in whole breast irradiation of early stage breast cancer. Int J Cancer Ther Oncol 2014; 2:020318.

Moorthy S, Sakr H, Hasan S, et al. Dosimetric study of SIB-IMRT versus SIB-3DCRT for breast cancer with breath-hold gated technique. Int J Cancer Ther Oncol 2013; 1:010110.

Popescu CC, Olivotto IA, Beckham WA, et al. Volumetric modulated arc therapy improves dosimetry and reduces treatment time compared to conventional intensity-modulated radiotherapy for locoregional radiotherapy of left-sided breast cancer and internal mammary nodes. Int J Radiat Oncol Biol Phys 2010; 76:287-95.

Johansen S, Cozzi L, Olsen DR. A planning comparison of dose patterns in organs at risk and predicted risk for radiation induced malignancy in the contralateral breast following radiation therapy of primary breast using conventional, IMRT and volumetric modulated arc treatment techniques. Acta Oncol 2009; 48:495-503.

Oliver M, Ansbacher W, Beckham WA. Comparing planning time, delivery time and plan quality for IMRT, RapidArc and Tomotherapy. J Appl Clin Med Phys 2009; 10:3068.

Nicolini G, Clivio A, Fogliata A, et al. Simultaneous integrated boost radiotherapy for bilateral breast: a treatment planning and dosimetric comparison for volumetric modulated arc and fixed field intensity modulated therapy. Radiat Oncol 2009; 4:27.




DOI: http://dx.doi.org/10.14319/ijcto.32.10

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.

------------------------------------------------------------

International Journal of Cancer Therapy and Oncology (ISSN 2330-4049)

© International Journal of Cancer Therapy and Oncology (IJCTO)

To make sure that you can receive messages from us, please add the 'ijcto.org' domain to your e-mail 'safe list'. If you do not receive e-mail in your 'inbox', check your 'bulk mail' or 'junk mail' folders.

------------------------------------------------------------

Number of visits since October, 2013
AmazingCounters.com