VACUUM AND THERMOPLASTIC MOULD-BASED IMMOBILIZATION SYSTEMS USED IN PATIENT UNDERGOING PELVIC RADIATION THERAPY: A COMPARATIVE STUDY
Keywords:Rotational therapy; Radiotherapy; Systematic, random error; Thermoplastic mould; Vacuum cushion
Introduction: The aim of the present study was to compare two immobilization systems for comparison of setup errors in targeted radiotherapy.
Methods: Retrospective analysis was done for the patients undergoing radiotherapy from May 2012 to December 2018 at our institution. Immobilization was performed on 30 patients sessions (Vacuum cushion i.e., Vac-Lok™ = 15; Thermoplastic mould i.e., Pelvicast pelvic masks = 15). A total of 763 cone-beams were analysed. The target lesion location was verified by cone-beam computed tomography (CBCT) prior to each session, with displacements assessed by CBCT simulation prior to each treatment session. Systematic setup errors, random setup errors, isocenter deviations in the Medio-lateral (ML), Supero-inferior (SI), Antero-posterior (AP), Rotation (yaw) directions of the patient position was calculated.
Results: On comparing the Vac-Lok™ and Pelvicast pelvic masks group with respect to Systematic and random error in the lateral, longitudinal, vertical and YAW direction, no statistically significant difference was seen except the random error in YAW direction (P=0.037, Unpaired t-test). There was no difference observed in comparing the isocentric deviation.
Conclusion: It was inferred and concluded that using a vacuum cushion for pelvic radiotherapy provides no added benefit compared to using a thermoplastic mould. Thermoplastic mould is recommended for patients receiving pelvic radiotherapy to improve overall reproducibility.
Keywords: Rotational therapy; Radiotherapy; Systematic, random error; Thermoplastic mould; Vacuum cushion.
Zhang X, Penagaricano J, Moros EG, Corry PM, Yan Y, Ratanatharathorn V. Dosimetric comparison of helicon tomotherapy and linac-IMRT treatment plans for head and neck cancer patients. Med Dosim 2010;35:264–8.
Faiz MK. Treatment planning in radiation oncology. 2nd edn. Philadelphia, PA: Lippincott William & Wilkins; 2007;169.
Gilbeau L, Octave-Prignot M, Loncol T, Renard R, Scalliet P, Gregoire V. Comparison of setup accuracy of three different thermoplastic masks for the treatment of brain and head and neck tumours. Radiother Oncol 2001;58:155–62.
Kneebone A, Gebski V, Hogendoorn N, Turner S. A randomized trial evaluating rigid immobilisation for pelvic irradiation. Int J Radiat Oncol Biol Phys 2003;56:1105–11.
Rosenthal SA, Roche M, Goldsmith BJ, Doggett EC, Pickett B, Yuo HS, et al. Immobilisation improves the reproducibility of patient positioning during 6-field conformal radiation therapy for prostate carcinoma. Int J Radiat Oncol Bio Phys 1993; 27: 921–6.
Soffen EM, Hanks GE, Hwang CC, Chu JC. Conformal static field therapy for low volume, low grade prostate cancer with rigid immobilisation. Int J Radiat Oncol Biol Phys 1991;20:141–6.
Li H, Zhu XR, Zhang L, Dong L, Tung S, Ahamad A, et al. Comparison of 2D radiographic images and 3D cone beam computed tomotherapy for positioning head and neck radiotherapy patients. Int J Radiat Oncol Biol Phys 2008; 71: 916–25.
Bel A, Vos PH, Rodrigus PT, Creutzberg CL, Visser AG, Stroom JC, et al. High-precision prostate cancer irradiation by clinical application of an offline patient setup verification procedure, using portal imaging. Int J Radiat Oncol Biol Phys 1996;35: 321–32.
De Boer JCJ, van Sornsen de Koste JR, Senan S, Visser AG, Heijmen BJ. Analysis and reduction of 3D systematic and random setup errors during the simulation and treatment of lung cancer patients with CT-based external beam radiotherapy dose planning. Int Radiat Oncol Biol Phys 2001;50:1350–65.
Stroom JC, de Boer HC, Huizenga H, Visser AG. Inclusion of geometrical uncertainties in radiotherapy treatment planning by means of coverage probability. Int Radiat Oncol Biol Phys 1999; 43: 905–19.
Stroom JC, Koper PC, Korevaar GA, van Os M, Janssen M, de Boer HC, et al. Internal organ motion on prostate cancer patients treated in prone and supine treatment position. Int Radiat Oncol Biol Phys 1999;51:273–48.
Van Herk M, Bruce A, Kroes AP, Shouman T, Touw A, Lebesque JV. Quantification of organ motion during conformal radiotherapy of the prostate by three dimensional image registration. Int Radiat Oncol Biol Phys 1995; 33: 1311–20.
Boda-Heggemann J, Walter C, Rahn A, Wertz H, Loeb I, Lohr F, et al. Repositioning accuracy of two different mask systems-3D revisited: comparison using true 3D/3D matching with cone beam CT. Int J Radiat Oncol Biol Phys 2006; 66: 1568–75.
Rabinowitz I, Broomberg J, Goitein M, McCarthy K, Leong J. Accuracy of radiation field alignment in clinical practice. Int J Radiat Oncol Biol Phys 1985;11:1857-67.
Siebers JV, Keall PJ, Wu Q, Williamson JF, Schmidt-Ullrich RK. Effect of patient setup errors on simultaneously integrated boost head and neck IMRT treatment plans. Int J Radiat Oncol Biol Phys 2005;63:422-33.
Song S, Yenice KM, Kopec M, Liauw SL. Image-guided radiotherapy using surgical clips as fiducial markers after prostatectomy: A report of total setup error, required PTV expansion, and dosimetric implications. Radiother Oncol 2012;103:270-4.
Ahamad A, D′Souza W, Salehpour M, Iyer R, Tucker SL, Jhingran A, et al. Intensity-modulated radiation therapy after hysterectomy: Comparison with conventional treatment and sensitivity of the normal-tissue-sparing effect to margin size. Int J Radiat Oncol Biol Phys 2005;62:1117-24.
Kinzie JJ, Hanks GE, MacLean CJ, Kramer S. Patterns of care study: Hodgkin′s disease relapse rates and adequacy of portals. Cancer 1983;52:2223-6.
Senan S, Chapet O, Lagerwaard FJ, Ten Haken RK. Defining target volumes for non-small cell lung carcinoma. Semin Radiat Oncol 2004;14:308-14.
Song PY, Washington M, Vaida F, Hamilton R, Spelbring D, Wyman B, et al. A comparison of four patient immobilization devices in the treatment of prostate cancer patients with three dimensional conformal radiotherapy. Int J Radiat Oncol Biol Phys 1996;34:213-9.
Aggarwal A. A comparison between four immobilization systems for pelvic radiation therapy using CBCT and paired kilovoltage portals based image-guided radiotherapy. Journal of Cancer Research and Therapeutics. 2014;10(4):932-6.
Cheng K-F, Wu VWC. Comparison of the effectiveness of different immobilization systems in different body regions using daily megavoltage CT in helical tomotherapy. Br J Radiol 2014;87:20130494.
Saini G. A comparison between four immobilization systems for pelvic radiation therapy using CBCT and paired kilovoltage portals based image-guided radiotherapy. Journal of Cancer Research and Therapeutics 2014;10(4):10.
How to Cite
Copyright (c) 2020 Mayuresh Virkar, N Arul Kumar, Pranav Chadha, Reuben Jake Rodrigues, Anup Kharde
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
The journal allows the author(s) to hold the copyright without restrictions and will retain publishing rights without restrictions.