Craniospinal Irradiation Using Three-Dimensional Conformal Radiotherapy with Two Different Planning Techniques: A Comparative Analysis in Supine and Prone Positions
Asian Oncology Research Journal,
Objectives: Craniospinal Irradiation (CSI) requires radiotherapy delivery to the entire neuraxis. It is accomplished by using multiple overlapping beams covering the large target volume, which are then matched to one another using collimation, couch rotation or beam modifications. Although modern radiotherapy techniques like Intensity Modulated Radiotherapy (IMRT) and Proton Beam Therapy (PBT) offer significant advantages in delivering CSI, yet 3-Dimensional Conformal Radiotherapy (3DCRT) remains the primarily used technique- more so in resource constrained settings.
Materials and Methods: The CT simulation datasets of six patients (3 supine and 3 prone positions) were used for planning two different techniques for CSI: A) Two isocenter plan with half beam block and no collimator rotation (2iso-HB-WOC) and B) Three isocenter plan with half beam block and collimator rotation (3iso-HB-WC). Plans were compared using Dose Volume Histogram (DVH) parameters for Planning Target Volume (PTV) and Organs at Risk (OARs).
Results: Considering dosimetric parameters, the 2iso-HB-WOC technique was found to be equivalent to 3iso-HB-WC technique in terms of PTV coverage and OAR doses. However, on evaluating treatment positions, the volume of hotspots (V107%) was significantly lesser [Mean: 141.83cc vs 243.50cc, p=0.02] with improved minimum dose (Dmin) in PTV [Mean: 29.68Gy vs 14.49Gy, p=0.03] for supine than in prone position. Also, the maximum point dose (Dmax) to the mandible was significantly lower in patients treated in supine position [37.0Gy vs 31.31Gy, p=0.01].
Conclusion: We suggest 2iso-HB-WOC technique for delivering CSI with 3DCRT. Also, supine positioning of patients in CSI appears to be dosimetrically advantageous.
- Craniospinal irradiation
- half-beam block
How to Cite
Shibamoto Y. Management of central nervous system germinoma: proposal for a modern strategy. Prog Neurol Surg. 2009; 23:119-129.
Massimino M, Gandola L, Biassoni V, et al. Evolving of therapeutic strategies for CNS-PNET. Pediatr Blood Cancer. 2013; 60(12):2031-2035.
Tsang DS, Murray L, Ramaswamy V, et al. Craniospinal irradiation as part of re-irradiation for children with recurrent intracranial ependymoma. Neuro Oncol. 2019;21(4):547-557.
Safia K. Ahmed, Jon J. Kruse, Thomas B. Bradley, Chris J Beltran,Nadia N Issa Laack. Clinical efficacy and safety of a highly conformal, supine, hybrid forward and inverse planned intensity modulated radiation therapy technique for craniospinal irradiation, Acta Oncologica. 2018; 57(5):629-636.
Van Dyk J, Jenkin RD, Leung PM, et al. Medulloblastoma: Treatment technique and radiation dosimetry. Int J Radiat Oncol Biol Phys. 1977;2:993–1005.
Grabenbauer GG, Beck JD, Erhardt J, et al. Postoperative radiotherapy of medulloblastoma. Impact of radiation quality on treatment outcome. Am J Clin Oncol. 1996;19(1):73-77.
Parker WA, Freeman CR. A simple technique for craniospinal radiotherapy in the supine position. Radiother Oncol. 2006;78:217–22.
Thomadsen B, Mehta M, Howard S, et al. Craniospinal treatment with the patient supine. Med Dosim. 2003;28:35–8.
Hawkins RB. A simple method of radiation treatment of craniospinal fields with the patient supine. Int J Radiat Oncol Biol Phys. 2001;49:261–4.
Holupka EJ, Humm JL, Tarbell NJ, Svensson GK. Effect of set-up error on the dose across the junction of matching cranial-spinal fields in the treatment of medulloblastoma. Int J Radiat Oncol Biol Phys. 1993;27(2):345-352.
Studenski MT, Shen X, Yu Y, et al. Intensity-modulated radiation therapy and volumetric-modulated arc therapy for adult craniospinal irradiation-- A comparison with traditional techniques. Med Dosim. 2013; 38(1):48-54.
Schiopu SR, Habl G, Häfner M, et al. Craniospinal irradiation using helical tomotherapy for central nervous system tumors. J Radiat Res. 2017;58(2):238-246.
Sharma DS, Gupta T, Jalali R, Master Z, Phurailatpam RD, Sarin R. High-precision radiotherapy for craniospinal irradiation: evaluation of three-dimensional conformal radiotherapy, intensity-modulated radiation therapy and helical TomoTherapy. Br J Radiol. 2009;82(984):1000-1009.
Mahajan A. Proton craniospinal radiation therapy: Rationale and clinical evidence. International Journal of Particle Therapy. 2014;1(2):399-407.
DeLaney TF. Proton therapy in the clinic. Front Radiat Ther Oncol. 2011;43: 465-485.
Lee S, Kim YB, Kwon S II, Chu SS, Suh CO. CT Simulation TECHNIQUE for craniospinal irradiation in supine position. Radiat Oncol J. 2002;20(2):165-171.
Ajithkumar T, Horan G, Padovani L, et al. SIOPE - Brain tumor group consensus guideline on craniospinal target volume delineation for high-precision radiotherapy. Radiother Oncol. 2018;128(2):192-197.
da Silveira MA, Pavoni JF, Bruno AC, Arruda GV, Baffa O. Three-Dimensional Dosimetry by Optical-CT and Radiochromic Gel Dosimeter of a Multiple Isocenter Craniospinal Radiation Therapy Procedure. Gels. 2022;8(9):582.
Published 2022 Sep 13.
Ahmed SK, Kruse JJ, Bradley TB, Beltran CJ, Laack NNI. Clinical efficacy and safety of a highly conformal, supine, hybrid forward and inverse planned intensity modulated radiation therapy technique for craniospinal irradiation. Acta Oncologica. 2018;57(5):629-636.
Biltekin F, Yazici G, Ozyigit G. A novel inverse optimization based three-dimensional conformal radiotherapy technique in craniospinal irradiation. Phys Eng Sci Med. 2021;44(1):265-275.
Munshi A, Jalali R. A simple technique of supine craniospinal irradiation. Med Dosim. 2008;33(1):1-5.
Abstract View: 157 times
PDF Download: 21 times