Standardized treatment planning methodology for passively scattered proton craniospinal irradiation

Radiation Oncology

Rebecca M Howell¹  Kenneth Homann¹  Anita Mahajan³  Richard A Amos¹  Wayne D Newhauser⁴  Annelise Giebeler² 

[1] The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA;Current Address: Scripps Proton Therapy Center, San Diego, CA, USA;Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA;Current Address: Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA

关键词: Medulloblastoma;    CSI;    Craniospinal irradiation;    Proton;   

Others  :  1154610
DOI  :  10.1186/1748-717X-8-32

 received in 2012-08-16, accepted in 2013-01-04,  发布年份 2013

【 摘 要 】

Background

As the number of proton therapy centers increases, so does the need for studies which compare proton treatments between institutions and with photon therapy. However, results of such studies are highly dependent on target volume definition and treatment planning techniques. Thus, standardized methods of treatment planning are needed, particularly for proton treatment planning, in which special consideration is paid to the depth and sharp distal fall-off of the proton distribution. This study presents and evaluates a standardized method of proton treatment planning for craniospinal irradiation (CSI).

Methods

We applied our institution’s planning methodology for proton CSI, at the time of the study, to an anatomically diverse population of 18 pediatric patients. We evaluated our dosimetric results for the population as a whole and for the two subgroups having two different age-specific target volumes using the minimum, maximum, and mean dose values in 10 organs (i.e., the spinal cord, brain, eyes, lenses, esophagus, lungs, kidneys, thyroid, heart, and liver). We also report isodose distributions and dose-volume histograms (DVH) for 2 representative patients. Additionally we report population-averaged DVHs for various organs.

Results

The planning methodology here describes various techniques used to achieve normal tissue sparing. In particular, we found pronounced dose reductions in three radiosensitive organs (i.e., eyes, esophagus, and thyroid) which were identified for optimization. Mean doses to the thyroid, eyes, and esophagus were 0.2%, 69% and 0.2%, respectively, of the prescribed dose. In four organs not specifically identified for optimization (i.e., lungs, liver, kidneys, and heart) we found that organs lateral to the treatment field (lungs and kidneys) received relatively low mean doses (less than 8% of the prescribed dose), whereas the heart and liver, organs distal to the treatment field, received less than 1% of the prescribed dose.

Conclusions

This study described and evaluated a standardized method for proton treatment planning for CSI. Overall, the standardized planning methodology yielded consistently high quality treatment plans and perhaps most importantly, it did so for an anatomically diverse patient population.

【 授权许可】

   
2013 Giebeler et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

Figure 4.

Figure 5.

Figure 6.

Figure 7.

【 参考文献 】

• [1]Olsen DR: Proton therapy - a systematic review of clinical effectiveness. Radiother Oncol 2007, 83(2):123-132.
• [2]Goozner M: The proton beam debate: are facilities outstripping the evidence? J Natl Cancer Inst 2010, 102(7):450-453.
• [3]Brada M, Pijls-Johannesma M, De Ruysscher D: Current clinical evidence for proton therapy. Cancer J 2009, 15(4):319-324.
• [4]Hall EJ: Is there a place for quantitative risk assessment? J Radiol Prot 2009, 29(2A):A171-A184.
• [5]Merchant TE: Proton beam therapy in pediatric oncology. Cancer J 2009, 15(4):298-305.
• [6]Newhauser WD, Durante M: Assessing the risk of second malignancies after modern radiotherapy. Nat Rev Cancer 2011, 11(6):438-448.
• [7]St Clair WH: Advantage of protons compared to conventional X-ray or IMRT in the treatment of a pediatric patient with medulloblastoma. Int J Radiat Oncol Biol Phys 2004, 58(3):727-734.
• [8]Taddei PJ: Predicted risks of second malignant neoplasm incidence and mortality due to secondary neutrons in a girl and boy receiving proton craniospinal irradiation. Phys Med Biol 2010, 55(23):7067-7080.
• [9]Yoon M: Craniospinal irradiation techniques: a dosimetric comparison of proton beams with standard and advanced photon radiotherapy. Int J Radiat Oncol Biol Phys 2011, 81(3):637-646.
• [10]Yuh GE: Reducing toxicity from craniospinal irradiation: using proton beams to treat medulloblastoma in young children. Cancer J 2004, 10(6):386-390.
• [11]Hansen EK, Roach M: Handbook of evidence-based radiation oncology. New York: Springer; 2010.
• [12]Yock TI: Pediatric tumors. Philadelphia: Lippincott Williams and Wilkins; 2008.
• [13]Woo S: Rationale for Proton Therapy in Pediatric Malignancies. In Ion Beam Therapy. Edited by Linz U. Berlin Heidelberg: Springer; 2012:277-286.
• [14]Lee CT: Treatment planning with protons for pediatric retinoblastoma, medulloblastoma, and pelvic sarcoma: how do protons compare with other conformal techniques? Int J Radiat Oncol Biol Phys 2005, 63(2):362-372.
• [15]Inskip PD, Curtis RE: New malignancies following childhood cancer in the United States, 1973–2002. Int J Cancer 2007, 121(10):2233-2240.
• [16]Terasawa T: Systematic review: charged-particle radiation therapy for cancer. Ann Intern Med 2009, 151(8):556-565.
• [17]Lodge M: A systematic literature review of the clinical and cost-effectiveness of hadron therapy in cancer. Radiother Oncol 2007, 83(2):110-122.
• [18]Brada M, Pijls-Johannesma M, De Ruysscher D: Proton therapy in clinical practice: current clinical evidence. J Clin Oncol 2007, 25(8):965-970.
• [19]Durante M, Loeffler JS: Charged particles in radiation oncology. Nat Rev Clin Oncol 2010, 7(1):37-43.
• [20]Yom SS: Field-in-field technique with intrafractionally modulated junction shifts for craniospinal irradiation. Int J Radiat Oncol Biol Phys 2007, 69(4):1193-1198.
• [21]Bentel G: Radiation therapy planning: Including problems and solutions. New York: McGraw-Hill, Health Professions Division; 1996.
• [22]Vann A: Portal design in radiation therapy. Columbia: R.L. Bryan Co; 2006.
• [23]Newhauser W: Monte Carlo simulations for configuring and testing an analytical proton dose-calculation algorithm. Phys Med Biol 2007, 52(15):4569-4584.
• [24]Smith A: The M. D. Anderson proton therapy system. Med Phys 2009, 36(9):4068-4083.
• [25]Schaffner B: Proton dose calculation based on in-air fluence measurements. Phys Med Biol 2008, 53(6):1545-1562.
• [26]ICRU: ICRU report 78 - prescribing, recording, and reporting proton-beam therapy. Vol. 7(2). Bethesdam: International Commission on Radiation Units and Measurements; 2007.
• [27]Bussiere MR, Adams JA: Treatment planning for conformal proton radiation therapy. Technol Cancer Res Treat 2003, 2(5):389-399.
• [28]Dong L: A digital couch solution for treatment planning beams through the treatment couch PTCOG, Vol. 46. China: Wanjie; 2006.
• [29]Kim JS: Modeling of a digital couch for a proton treatment planning system. J Korean Phys Soc 2009, 55(4):1640-1648.
• [30]Newhauser WD: Can megavoltage computed tomography reduce proton range uncertainties in treatment plans for patients with large metal implants? Phys Med Biol 2008, 53(9):2327-2344.
• [31]Howell RM: Comparison of therapeutic dosimetric data from passively scattered proton and photon craniospinal irradiations for medulloblastoma. Radiat Oncol 2012, 7:116. BioMed Central Full Text
• [32]Brodin NP: Radiobiological risk estimates of adverse events and secondary cancer for proton and photon radiation therapy of pediatric medulloblastoma. Acta Oncol 2011, 50(6):806-816.
• [33]Zhang X: Effect of anatomic motion on proton therapy dose distributions in prostate cancer treatment. Int J Radiat Oncol Biol Phys 2007, 67(2):620-629.
• [34]Moyers MF, Miller DW: Range, range modulation, and field radius requirements for proton therapy of prostate cancer. Technol Cancer Res Treat 2003, 2(5):445-447.
• [35]Moyers MF: Methodologies and tools for proton beam design for lung tumors. Int J Radiat Oncol Biol Phys 2001, 49(5):1429-1438.
• [36]Urie M, Goitein M, Wagner M: Compensating for heterogeneities in proton radiation therapy. Phys Med Biol 1984, 29(5):553-566.
• [37]Lunsford TR, Lunsford BR: The research sample, part I: sampling. J Prosthetics Orthotics 1995, 7(3):105-112.
• [38]Miralbell R: Potential reduction of the incidence of radiation-induced second cancers by using proton beams in the treatment of pediatric tumors. Int J Radiat Oncol Biol Phys 2002, 54(3):824-829.
• [39]Newhauser WD: The risk of developing a second cancer after receiving craniospinal proton irradiation. Phys Med Biol 2009, 54(8):2277-2291.