Which radiotherapy technique is better for neoadjuvant treatment of rectal cancer: A dosimetric comparison
Objective: Our aim was to compare helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT) plans with 3-dimensional conformal radiotherapy (3D-CRT) considering the planning target volume (PTV) and organs at risk (OARs) in rectal cancer patients treated with neoadjuvant radiotherapy. Patients and Methods: Thirty patients, previously treated with intensity modulated radiotherapy (IMRT) or 3D-CRT from January 2014 to February 2020 were selected and 3 plans were generated for each patient using VMAT, HT and 3D-CRT. Dosimetric comparisons were made for each plan regarding PTV and OARs. Integral dose (ID) was calculated and beam on times were analyzed. Results: The homogeneity index (HI) was significantly better in HT plans compared with VMAT and 3D-CRT plans (p<0.001), conformity index (CI) was better in VMAT plans. For small bowel, high doses were higher in 3D-CRT plans (p <0.001). HT produced lower doses for the bladder as compared to VMAT and 3D-CRT (p<0.005). The mean and maximum doses of bilateral femoral heads were higher in 3D-CRT plans. Beam on times were longer and IDs were higher in HT plans (p<0.001). Conclusion: Both VMAT and HT improved target homogeneity and conformity and decreased OAR doses compared to 3D-CRT. Although, VMAT was the best method to decrease ID, HT produced better bladder sparing.
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- [1] Sung H, Ferlay J, Siegel RL, Laversanne M, et al. Global Cancer
Statistics 2020: GLOBOCAN Estimates of Incidence and
Mortality Worldwide for 36 Cancers in 185 Countries. CA
Cancer J Clin 2021;71:209-49. doi: 10.3322/caac.21660.
- [2] Sauer R, Sauer R, Liersch T, et al. Preoperative versus
postoperative chemoradiotherapy for rectal cancer. N Engl J
Med 2004. 351: 1731-40. doi: 10.1056/NEJMoa040694.
- [3] Bosset JF, Collette L, Calais G, et al. Chemotherapy with
preoperative radiotherapy in rectal cancer. N Engl J Med 2006;
355:1114-23. doi: 10.1056/NEJMoa060829.
- [4] Zorcolo L, Rosman AS, Restivo A, et al. Complete pathologic
response after combined modality treatment for rectal cancer
and long-term survival: a meta-analysis. Ann Surg Oncol
2012. 19:2822-32. doi: 10.1245/s10434.011.2209-y.
- [5] Clifford R, Govindarajah N, Parsons JL, Gollins S, West
NP, Vimalachandran D. Systematic review of treatment
intensification using novel agents for chemoradiotherapy
in rectal cancer. Br J Surg 2018 ;105:1553-72. doi: 10.1002/
bjs.10993.
- [6] Burbach JP, den Harder AM, Intven M, van Vulpen M,
Verkooijen HM, Reerink O. Impact of radiotherapy boost
on pathological complete response in patients with locally
advanced rectal cancer: a systematic review and metaanalysis.
Radiother Oncol 2014; 113:1-9. doi: 10.1016/j.radonc.2014.08.035.
- [7] Valentini V, Gambacorta MA, Cellini F, et al. The INTERACT
Trial: Long-term results of a randomised trial on preoperative
capecitabine-based radiochemotherapy intensified by
concomitant boost or oxaliplatin, for cT2 (distal)-cT3 rectal
cancer. Radiother Oncol 2019 ;134:110-8. doi: 10.1016/j.
radonc.2018.11.023.
- [8] Baglan KL, Frazier RC, Yan D, Huang RR, Martinez AA,
Robertson JM. The dose-volume relationship of acute small
bowel toxicity from concurrent 5-FU-based chemotherapy
and radiation therapy for rectal cancer. Int J Radiat Oncol Biol
Phys 2002;52:176-83. doi: 10.1016/s0360-3016(01)01820-x.
- [9] International Commission on Radiation Units and
Measurements. ICRU Report 62. Prescribing, recording, and
reporting photon beam therapy (Supplement to ICRU Report
50). Bethesda, MD: ICRU, 1999:1-20.
- [10] Theodore S Hong, Jennifer Moughan, Michael C Garofalo, et
al. NRG Oncology Radiation Therapy Oncology Group 0822:
A Phase 2 Study of Preoperative Chemoradiation Therapy
Using Intensity Modulated Radiation Therapy in Combination
With Capecitabine and Oxaliplatin for Patients With Locally
Advanced Rectal Cancer. Int J Radiat Oncol Biol Phys 2015
;93:29-36. doi: 10.1016/j.ijrobp.2015.05.005.
- [11] Aoyama H, Westerly DC, Mackie TR, et al. Integral radiation
dose to normal structures with conformal external beam
radiation. Int J Radiat Oncol Biol Phys 2006;64:962-7. doi:
10.1016/j.ijrobp.2005.11.005.
- [12] Marco D’Arienzo, Stefano G Masciullo, Vitaliana de Sanctis,
et al. Integral dose and radiation-induced secondary
malignancies: comparison between stereotactic body radiation
therapy and three-dimensional conformal radiotherapy Int
J Environ Res Public Health 2012; 9:4223-40. doi:10.3390/
ijerph9114223.
- [13] Onay Ö, Ünal Karabey A, Morgül Y, Karabey MS. A
comparative planning study of step – and – shoot IMRT
versus helical tomotherapy IMRT in the treatment of
craniospinal tumor. Turkish J Oncol 2014;29:46-52. doi:
10.5505/tjoncol.2014.1059
- [14] Arbea L, Ramos LI, Martínez-Monge R, Moreno M, Aristu
J: Intensity modulated radiation therapy (IMRT) vs. 3D
conformal radiotherapy (3DCRT) in locally advanced
rectal cancer (LARC): dosimetric comparison and clinical
implications. Radiat Oncol 2010;5:17. doi: 10.1186/1748-
717X-5-17.
- [15] Yu M, Jang HS, Jeon DM, et al. Dosimetric evaluation of
tomotherapy and four-box field conformal radiotherapy in
locally advanced rectal cancer. Radiat Oncol J 2013;31: 252-9.
doi: 10.3857/roj.2013.31.4.252.
- [16] Lin JC, Tsai JT, Chen LJ, Li MH, Liu WH. Compared planning
dosimetry of TOMO, VMAT and IMRT in rectal cancer with
different simulated positions. Oncotarget 2017;8: 42020-29.
doi: 10.18632/oncotarget.14923.
- [17] Wen G, Zhang J, Chi F, et al. Dosimetric comparison of
volumetric modulated arc therapy (VMAT), 5F intensity
modulated radiotherapy (IMRT) and 3D conformal
radiotherapy (3DCRT) in rectal carcinoma receiving
neoadjuvant chemoradiotherapy. Int J Med Phys Clin Eng and
Radiol Oncol 2015;4:54-63.doi: 10.4236/ijmpcero.2015.41008.
- [18] Simson DK, Mitra S, Ahlawat P, Sharma MK, Yadav G, Mishra
MB. Dosimetric comparison between intensity modulated
radiotherapy and 3 dimensional conformal radiotherapy in
the treatment of rectal cancer. Asian Pac J Cancer Prev 2016
;17:4935-7. doi: 10.22034/APJCP.2016.17.11.4935.
- [19] Bakkal BH, Elmas O. Dosimetric comparison of organs
at risk in 5 different radiotherapy plans in patients with
preoperatively irradiated rectal cancer. Medicine (Baltimore)
2021;100(1):e24266. doi: 10.1097/MD.000.000.0000024266.
- [20] Braendengen M, Tveit KM, Berglund A, et al. Randomized
phase III study comparing preoperative radiotherapy with
chemoradiotherapy in nonresectable rectal cancer. J Clin
Oncol 2008 ;26:3687-94. doi: 10.1200/JCO.2007.15.3858.
- [21] Tho LM, Glegg M, Paterson J, et al. Acute small bowel toxicity
and preoperative chemoradiotherapy for rectal cancer:
investigating dose-volume relationships and role for inverse
planning. Int J Radiat Oncol Biol Phys 2006;66:505-13. doi:
10.1016/j.ijrobp.2006.05.005.
- [22] Robertson JM, Lockman D, Yan D, Wallace M. The dosevolume
relationship of small bowel irradiation and acute
grade 3 diarrhea during chemoradiotherapy for rectal cancer.
Int J Radiat Oncol Biol Phys 2008;70:413-8. doi: 10.1016/j.
ijrobp.2007.06.066.
- [23] Holyoake DLP, Partridge M, Hawkins MA. Systematic
review and meta-analysis of small bowel dose-volume and
acute toxicity in conventionally-fractionated rectal cancer
radiotherapy. Radiother Oncol 2019;138:38-44. doi: 10.1016/j.
radonc.2019.05.001.
- [24] Temelli O, Demirtas M, Ugurlu BT, Bag HG. Integral dose
and dosimetric comparison of neoadjuvant simultaneous
integrated boost (SIB) radiotherapy technique for rectal cancer
using intensity-modulated radiotherapy (IMRT), volumetric
modulated arc therapy (VMAT), and helical tomotherapy
(HT). Int J Hematol Oncol 2019; 29: 147-56. doi: 10.4999/
uhod.193839.
- [25] Grigsby PW, Roberts HL, Perez CA. Femoral neck fracture
following groin irradiation. Int J Radiat Oncol Biol Phys 1995
;32::63-7. doi: 10.1016/0360-3016(95)00546-B.
- [26] Rasmusson E, Nilsson P, Kjellén E, Gunnlaugsson A. Longterm
risk of hip complications after radiation therapy for
prostate cancer: A dose-response study. Adv Radiat Oncol
2020;;6:100571. doi: 10.1016/j.adro.2020.09.011.