Trajectory modulated arc therapy using quasi-continuous couch motion layered on top of volumetric modulated arc therapy in left breast and chest wall irradiation: a feasibility study

AbstractAimTo investigate the dosimetric advantage of quasi-continuous couch motion-enabled trajectory modulated arc radiotherapy therapy (TMAT) over the coplanar tangential partial arcs volumetric modulated arc radiotherapy (VMAT) for treating left breast and chest wall patients.MethodTreatment plans of 43 patients who received radiotherapy for left breast (17) or for left chest wall (26) using coplanar partial tangential arcs VMAT (reference plan) were considered for this study. For each patient, in addition to the treatment plan, a TMAT plan was also generated using quasi-continuous couch rotation. The TMAT plan consisted of original two 30° tangential arc beams and two supplementary beams having a couch rotation of ±10°, ±20° and ±30°, respectively. The difference in PTV volume coverage (PTV V95%) between TMAT plan and VMAT plan was calculated for all the cases and normalised to the plan’s prescription dose. Similarly, differences in PTV_V105% and several dose-volume parameters related to organs at risk (OAR) were also computed and tabulated.ResultTMAT shows an increment in the PTV dose coverage V95% with respect to reference plan by 4·7±2·5% when averaged overall prescription dose levels. Mean PTV dose (averaged overall prescription levels) for reference and TMAT plan was 4638·6±423·8 and 4793·5±447·2 cGy, respectively, and statistically insignificant (p=0·06). However mean PTV_V105% values for TMAT and for reference plans were 6·7±4·8 and 7·2±5·2%, respectively, and were not statistically different (p=0·85). Mean heart dose in TMAT was less than in VMAT plans, but not significantly. As regarding D1% to heart, TMAT plan was again found to be better with a mean difference of 137·1 cGy over VMAT plan. Other parameters evaluated were: mean dose and D1% to contralateral breast, and V20 Gy and V5 Gy for lung.ConclusionTMAT plans were found to be better than VMAT plans in terms of PTV coverage and D1% for heart. For evaluated dose parameters apart from PTV coverage and D1% to the heart, no significant differences were observed. Thus, TMAT plans yielded better dose distribution in terms of PTV dose coverage, hot spots and OAR doses.

Download Full-text

Treatment planning study of Volumetric Modulated Arc Therapy and three dimensional field-in-field techniques for left chest-wall cancers with regional lymph nodes

Reports of Practical Oncology & Radiotherapy ◽

10.1016/j.rpor.2016.07.005 ◽

2016 ◽

Vol 21 (6) ◽

pp. 517-524 ◽

Cited By ~ 4

Author(s):

Heping Xu ◽

Gillian Hatcher

Keyword(s):

Lymph Nodes ◽

Treatment Planning ◽

Chest Wall ◽

Volumetric Modulated Arc Therapy ◽

Three Dimensional ◽

Planning Study ◽

Regional Lymph Nodes ◽

Left Chest ◽

Field Techniques ◽

Arc Therapy

Download Full-text

Dosimetric Comparison of Volumetric Modulated Arc Therapy, Static Field Intensity Modulated Radiation Therapy, and 3D Conformal Planning for the Treatment of a Right-Sided Reconstructed Chest Wall and Regional Nodal Case

Journal of Radiotherapy ◽

10.1155/2014/835179 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Vishruta A. Dumane ◽

Margie A. Hunt ◽

Sheryl Green ◽

Yeh-Chi Lo ◽

Richard L. Bakst

Keyword(s):

Chest Wall ◽

Treatment Time ◽

Treatment Plan ◽

Volumetric Modulated Arc Therapy ◽

Intensity Modulated Radiation Therapy ◽

Static Field ◽

Target Coverage ◽

Delivery Method ◽

Intensity Modulated ◽

Arc Therapy

We compared 3D conformal planning, static field intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT) to investigate the suitable treatment plan and delivery method for a right-sided reconstructed chest wall and nodal case. The dose prescribed for the reconstructed chest wall and regional nodes was 50.4 Gy. Plans were compared for target coverage and doses of the lungs, heart, contralateral breast, and healthy tissue. All plans achieved acceptable coverage of the target and IMNs. The best right lung sparing achieved with 3D was a V20 Gy of 31.09%. Compared to it, VMAT reduced the same by 10.85% and improved the CI and HI over 3D by 18.75% and 2%, respectively. The ipsilateral lung V5 Gy to V20 Gy decreased with VMAT over IMRT by as high as 17.1%. The contralateral lung V5 Gy was also lowered with VMAT compared to IMRT by 16.22%. The MU and treatment beams were lowered with VMAT over IMRT by 30% and 10, respectively, decreasing the treatment time by >50%. VMAT was the treatment plan and delivery method of choice for this case due to a combination of improved lung sparing and reduced treatment time without compromising target coverage.

Download Full-text

Dosimetric Evaluation of Photons Versus Protons in Postmastectomy Planning for Ultrahypofractionated Breast Radiotherapy

10.21203/rs.3.rs-1113856/v1 ◽

2021 ◽

Author(s):

Puntiwa Oonsiri ◽

Chonnipa Nantavithya ◽

Chawalit Lertbutsayanukul ◽

Thanaporn Sarsitthithum ◽

Mananchaya Vimolnoch ◽

...

Keyword(s):

Radiation Therapy ◽

Chest Wall ◽

Organs At Risk ◽

Skin Dose ◽

Proton Radiation ◽

Breast Radiotherapy ◽

Left Chest ◽

Ipsilateral Lung ◽

Heart Dose ◽

The Right

Abstract Background: Ultrahypofractionation can shorten the irradiation period. This study is the first dosimetric investigation comparing ultrahypofractionation using volumetric arc radiation therapy (VMAT) and intensity-modulated proton radiation therapy (IMPT) techniques in postmastectomy treatment planning. Materials and methods: Twenty postmastectomy patients (10-left and 10-right sided) were replanned with both VMAT and IMPT techniques. There were 4 scenarios: left chest wall, left chest wall including regional nodes, right chest wall, and right chest wall including regional nodes. The prescribed dose was 26 Gy (RBE) in 5 fractions. For VMAT, a 1-cm bolus was added for 2 in 5 fractions. For IMPT, robust optimization was performed on the CTV structure with a 3-mm setup uncertainty and a 3.5% range uncertainty. This study aimed to compare the dosimetric parameters of the PTV, ipsilateral lung, contralateral lung, heart, skin, esophageal, and thyroid doses. Results: The PTV-D95 was kept above 24.7 Gy in both VMAT and IMPT plans. The ipsilateral lung mean dose of the IMPT plans was comparable to that of the VMAT plans. In three of four scenarios, the V5 of the ipsilateral lung in IMPT plans was lower than in VMAT plans. The Dmean and V5 of heart dose were reduced by a factor of 4 in the IMPT plans of the left side. For the right side, the Dmean of the heart was less than 1 Gy for IMPT, while the VMAT delivered approximately 3 Gy. The IMPT plans showed a significantly higher skin dose owing to the lack of a skin-sparing effect in the proton beam. The IMPT plans provided lower esophageal and thyroid mean dose. Conclusion: Despite the higher skin dose with the proton plan, IMPT significantly reduced the dose to adjacent organs at risk, which might translate into the reduction of late toxicities when compared with the photon plan. Key words: proton therapy, ultrahypofractionation, postmastectomy, breast irradiation

Download Full-text

Dosimetric characteristics of VMAT plans with respect to a different increment of gantry angle size for Ca cervix

Journal of Radiotherapy in Practice ◽

10.1017/s146039692000093x ◽

2020 ◽

pp. 1-5

Author(s):

Munirathinam Natraj ◽

P. N. Pawaskar ◽

Arun Chairmadurai

Keyword(s):

Cervical Cancer ◽

Volumetric Modulated Arc Therapy ◽

Target Volume ◽

Cervical Cancer Patient ◽

Conformity Index ◽

Arc Therapy ◽

Prescription Dose ◽

The Difference ◽

Radiotherapy Treatment ◽

Gantry Angle

Abstract Aim: We have investigated the influence in volumetric-modulated arc therapy (VMAT) plans by a sequence of increment of gantry angle (IGA) in definitive radiotherapy treatment for cervical cancer. The plans are quantitatively analysed in terms of conformity index (CI), heterogeneity index (HI), dose–gradient index (DGI), target coverage (TC) by prescription dose, monitor unit (MU) usage, control points (CPs) and dose to organs. Materials and Methods: In this retrospective study, we selected 27 patients with cervical cancer having aged between 54 and 69. All the patients enrolled in this study were at T3N1M0 stage of cervical cancer. The prescription dose to planning target volume (PTV) was 50 Gy and was administered in 2 Gy/fraction through VMAT technique. VMAT plans were optimised by varying the parameter ‘IGA’ as 10, 20, 30 and 40°. Results: Homogenous dose distribution within PTV and TC by prescription dose was significantly enhanced (p < 0·05) with larger IGA. The difference between volume receiving 15 Gy (V15Gy) in bowel was up to 10% with larger IGA (30 and 40°) and V25Gy in femoral head was up to 3% with smaller IGA (10 and 20°). CPs were enhanced and MU usage was reduced with larger IGA (30 and 40°). IGA 40° had reduced the MU usage than IGA 30° but the CI and DGI were compromised due to large MLC field segments. Conclusion: This study recommends that the larger IGA could yield better results when the number of sectors is even, for a cervical cancer patient. However, more data from more patients need to be obtained and analysed to make this an evidence-based hypothesis.

Download Full-text

Feasibility of Left-sided Chest Wall Irradiation with Volumetric Modulated Arc Therapy

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2010.07.542 ◽

2010 ◽

Vol 78 (3) ◽

pp. S226-S227

Author(s):

S. Thirumalai Swamy ◽

V. Subramanian ◽

M. Kathirvel ◽

G. Arun ◽

S. Chilukuri ◽

...

Keyword(s):

Chest Wall ◽

Volumetric Modulated Arc Therapy ◽

Arc Therapy

Download Full-text

Tangent-based volumetric modulated arc therapy for advanced left breast cancer

Radiation Oncology ◽

10.1186/s13014-018-1167-y ◽

2018 ◽

Vol 13 (1) ◽

Cited By ~ 4

Author(s):

Pei-Chieh Yu ◽

Ching-Jung Wu ◽

Hsin-Hua Nien ◽

Louis Tak Lui ◽

Suzun Shaw ◽

...

Keyword(s):

Breast Cancer ◽

Volumetric Modulated Arc Therapy ◽

Left Breast ◽

Arc Therapy

Download Full-text

Hybrid volumetric-modulated arc therapy for postoperative breast cancer including regional lymph nodes: the advantage of dosimetric data and safety of toxicities

Journal of Radiation Research ◽

10.1093/jrr/rraa057 ◽

2020 ◽

Vol 61 (5) ◽

pp. 747-754

Author(s):

Yoshiko Doi ◽

Minoru Nakao ◽

Hideharu Miura ◽

Shuichi Ozawa ◽

Masahiro Kenjo ◽

...

Keyword(s):

Breast Cancer ◽

Lymph Nodes ◽

Irradiation Dose ◽

Organs At Risk ◽

Volumetric Modulated Arc Therapy ◽

Conformity Index ◽

Regional Lymph Nodes ◽

Dosimetric Data ◽

Arc Therapy

ABSTRACT To improve the homogeneity and conformity of the irradiation dose for postoperative breast cancer including regional lymph nodes, we planned Hybrid volumetric-modulated arc therapy (VMAT), which combines conventional tangential field mainly for the chest area and VMAT mainly for the supraclavicular area and marginal zone. In this study, we compared the dosimetric impact between traditional 3D conformal radiotherapy (3DCRT) and Hybrid VMAT and observed toxicities following Hybrid VMAT. A total of 70 patients indicated between October 2016 and December 2017 were included. The prescribed dose was 50 Gy/25 fractions. For the dosimetric impact, 3DCRT and Hybrid VMAT plans were compared in each patient with respect to the dosimetric parameters. Toxicities were followed using the Common Terminology Criteria for Adverse Events version 4.0. The median follow-up duration was 319 days. For the dosimetric impact, the homogeneity index (HI) and conformity index (CI) of PTV were significantly improved in the Hybrid VMAT plan compared with that in the 3DCRT plan (HI, 0.15 ± 0.07 in Hybrid VMAT vs 0.41 ± 0.19 in 3DCRT, P < 0.001; CI, 1.61 ± 0.44 in Hybrid VMAT vs 2.10 ± 0.56 in 3DCRT, P < 0.001). The mean irradiated ipsilateral lung dose was not significantly different in both plans (12.0 ± 2.4 Gy in Hybrid VMAT vs 11.8 ± 2.8 Gy in 3DCRT, P < 0.533). Regarding toxicity, there were no patients who developed ≥grade 3 acute toxicity and ≥grade 2 pneumonitis during the follow-up. Hybrid VMAT for postoperative breast cancer including regional lymph nodes was a reasonable technique that improved the homogeneity and conformity of the irradiation dose to the planning target volume while keeping the irradiation dose to organs at risk to a minimum.

Download Full-text

Modern Rotational Radiation Techniques with Volumetric Modulated Arc Therapy or Helical Tomotherapy for Optimal Sparing of the Lung and Heart in Left-Breast Cancer Radiotherapy Plus Regional Nodal Irradiation: A Comparative Dosimetric Analysis

Cancers ◽

10.3390/cancers13205043 ◽

2021 ◽

Vol 13 (20) ◽

pp. 5043

Author(s):

Pei-Yu Hou ◽

Chen-Hsi Hsieh ◽

Le-Jung Wu ◽

Chen-Xiong Hsu ◽

Deng-Yu Kuo ◽

...

Keyword(s):

Breast Cancer ◽

Subgroup Analysis ◽

Helical Tomotherapy ◽

Volumetric Modulated Arc Therapy ◽

Left Breast ◽

Contralateral Breast ◽

Normal Organ ◽

Regional Nodal Irradiation ◽

Optimal Technique ◽

Arc Therapy

Background: For advanced breast cancer with lymph node involvement, adjuvant radiotherapy (RT) with regional nodal irradiation (RNI) has been indicated to reduce cancer recurrence and mortality. However, an extensive RT volume is associated with normal organ exposure, which increases the toxicity and affects patient outcomes. Modern arc RT techniques can improve normal organ sparing compared with conventional techniques. The aim of this study was to explore the optimal technique for left-breast RT with RNI. Methods: We retrospectively reviewed patients receiving RT with RNI for left-breast cancer. We used modern arc RT techniques with either volumetric-modulated arc therapy (VMAT) or helical tomotherapy (HT) with a novel block technique, and compared differences in dosimetry parameters between the two groups. Subgroup analysis of RNI with or without internal mammary node (IMN) volume was also performed. Results: A total of 108 eligible patients were enrolled between 2017 and 2020, of whom 70 received VMAT and 38 received HT. The median RT dose was 55 Gy. No significant differences were found regarding the surgery, RT dose, number of fractions, target volume, and RNI volume between the VMAT and HT groups. VMAT reduced the heart mean dose more than HT (3.82 vs. 5.13 Gy, p < 0.001), as well as the cardiac parameters of V5-V20, whole-lung mean dose, lung parameters of V5-V20, and contralateral-breast and esophagus mean dose. In the subgroup analysis of RNI with IMNs, the advantage of VMAT persisted in protecting the heart, lung, contralateral breast, and esophagus. HT was beneficial for lowering the thyroid mean dose. For RNI without IMN, VMAT improved the low-dose exposure of the heart and lung, but HT was similar to VMAT in terms of heart, whole-lung, and contralateral-breast mean dose. Conclusions: For patients with left-breast cancer receiving adjuvant RT with RNI, VMAT reduced the exposure dose to the heart, lung, contralateral breast, and esophagus compared with HT. VMAT was superior to HT in terms of normal organ sparing in the patients who underwent RNI with IMN irradiation. Considering the reduction in normal organ exposure and potential toxicity, VMAT is the optimal technique for patients receiving RNI when deep inspiration breath-hold is not available.

Download Full-text