TomoDirect Plans Research Articles

Influence of the Planning Parameters of a New Algorithm on the Dosimetric Quality, Beam-on Time and Delivery Accuracy of Tomotherapy Plans

Background: This work aimed to determine the optimum VOLOTM Ultra algorithm parameters for tomotherapy treatments. Methods: 1056 treatment plans were generated with VOLOTM Ultra for 36 patients and six anatomical locations. The impact of varying four parameters was studied: the accelerated treatment (AT), leaf open/close time (LOT) cutoff, normal tissue objective (NTO) weight, and number of iterations. The beam-on time and dosimetric metrics were quantified for the target volumes and organs at risk (OARs). Delivery quality assurance measurements were obtained for 36 plans to assess the delivery accuracy. Results: The mean beam-on time for the helical tomotherapy and TomoDirect (TD) plans decreased by 26.6 ± 2.8% and 17.4 ± 4.3%, respectively, when the accelerated treatment parameter was increased from 0 to 10, at the expense of the planning target volume (PTV) coverage (2% lower D98%) and OAR dose (up to 15% increase). For TD plans, it seems preferable to systematically use an AT value of 10. Increasing the number of iterations beyond six seems unnecessary. In this study, an NTO weight of approximately 10 appears to be ideal and eliminates the need to use rings in the treatment plan. Finally, no correlation was found between the leaf open/close time cutoff and the delivery accuracy, while a leaf open/close cutoff of 60 ms seemed to degrade dosimetry quality. Conclusion: Optimal values for the AT, LOT cutoff, NTO weight, and number of optimization rounds were identified and should help improve the management of patients whose tomotherapy treatments are planned with VOLOTM Ultra.

A Comparative Analysis of Implant-sparing Plan Versus Conventional Plans Utilizing Helical Tomotherapy in Breast Cancer Patients Undergoing Breast Reconstruction.

To compare implant sparing irradiation with conventional radiotherapy (RT) using helical (H) and TomoDirect (TD) techniques in breast cancer patients undergoing immediate breast reconstruction (IBR). The dosimetric parameters of 40 patients with retropectoral implants receiving 50.4 Gy delivered in 28 fractions were analyzed. Three plans were created: H plan using conventional planning target volume (PTV) that included the chest wall, skin, and implant; TD plan using conventional PTV; and Hs plan using implant-sparing PTV. The H, TD, and Hs plans were compared for PTV doses, organ-at-risk (OAR) doses, and treatment times. Dose distribution in the Hs plan was less homogeneous and uniform than that in the H and TD plans. The TD plan had lower lung, heart, contralateral breast, spinal cord, liver, and esophagus doses than the Hs plan. Compared to the Hs plan, the H plan had lower lung volume receiving 5Gy (V5) (39.1±3.9 vs. 41.2±3.9 Gy; p<0.001), higher V20 (12.3±1.3 vs. 11.5±2.6 Gy; p=0.02), and higher V30 (7.5±1.6 vs. 4.4±1.7 Gy; p<0.001). H plan outperformed Hs plan in heart dosimetric parameters except V20. The Hs plan had significantly lower mean implant doses (43.4±2.1 Gy) than the H plan (51.4±0.5 Gy; p<0.001) and the TD plan (51.9±0.6 Gy; p<0.001). Implementing an implant sparing technique for silicone dose reduction decreases lung doses. Conventional H and TD plans outperform the implant sparing helical plan dosimetrically. Because capsular contracture during RT is unpredictable, long-term clinical outcomes are required to determine whether silicon should be spared.

Comparison of helical and TomoDirect techniques with simultaneous integrated boost in early breast cancer patients.

The aim of the study was to perform dosimetric comparisons of helical (H) and TomoDirect (TD) plans for whole-breast irradiation (WBI) with simultaneous integrated boost (SIB) in early-stage breast cancer patients undergoing breast conserving surgery. Fifty patients, 25 with left-side and 25 with right-side tumors, were determined for a treatment planning system for a total dose of 50.4Gy in 1.8Gy per fraction to WBI, with a SIB of 2.3Gy per fraction delivered to the tumor bed. The planning target volume (PTV) doses and the conformity (CI) and homogeneity indices (HI) for PTVbreast and PTVboost, as well as organ-at-risk (OAR) doses and treatment times, were compared between the H and TD plans. All plans met the PTV coverage criteria for the H plan, except for mean V107 of PTVbreast for TD plan. The H plan yielded better homogeneity and conformity of dose distribution compared to the TD plan. The ipsilateral mean lung doses were not significantly different between the two plans. The TD plans is advantageous for mean doses to the heart, contralateral breast and lung, spinal cord, and esophagus than the H plans. In both the H and TD plans, the right-sided breast patients had lower heart dose parameters than the left-sided breast patients. The TD plan is superior to the H plan in sparing the contralateral breast and lung by decreasing low-dose volumes. While the OAR dose advantages of TD are appealing, shorter treatment times or improved dose homogeneity and conformity for target volume may be advantageous for H plan.

Hybrid Tomo-Helical and Tomo-Direct radiotherapy for localized prostate cancer.

PurposeThe aim of the study is to present a new planning approach to provide better planning target volume (PTV) coverage and reduce bladder and rectum dose with hybrid Tomo‐Helical (TH)/Tomo‐Direct (TD) radiotherapy (RT) for localized prostate cancer (LPC).MethodsTwenty‐five LPC patients were included in this retrospective study. TH plans, TD plans, and hybrid TH/TD plans were created. Lateral beams were used for the hybrid TD plan and the prescribed dose was 70 Gy in 28 fractions (hybrid plans were combined 45 Gy/ 18 fxs for TH and 25 Gy/10 fxs for TD). Doses of PTV (D2%, D98%, D50%, homogeneity index (HI), conformity index (CI), coverage) and organs at risk (OARs) (V50%, V35%, V25%, V5%, and V95%) were analyzed. The Wilcoxon signed‐rank test was used to analyze the difference in dosimetric parameters. p‐Value < 0.05 was considered statistically significant.ResultsTH plans showed better CI, and target coverage (p < 0.01) than TD and hybrid plans in all patient plan evaluations. However, TD plans D2%, D98%, and D50% doses were better than TH and hybrid plans. The HI values were similar between the three plans. Significant reductions in bladder and rectum V50%, V35%, and V25% doses (p < 0.001) were observed with hybrid plans compared to TH and TD. Penile bulb V95% and bowel V5% doses were better in the hybrid plans. Left and right femoral head V5% doses were higher in the hybrid plan compared to others (p < 0.001).ConclusionConcurrently hybrid TH/TD RT plan can be a good option to reduce the doses of the rectum and bladder in the RT of LPC.

Dosimetric comparison of TomoDirect, helical tomotherapy, and volumetric modulated arc therapy for postmastectomy treatment.

PurposeTo compare dose to the targets and organs at risk (OARs) in different situations for postmastectomy patients who require radiation to the chest wall with or without regional nodal irradiation when using three treatment techniques.Methods and materialsThirty postmastectomy radiotherapy (PMRT) patients previously treated by helical tomotherapy (HT) at our institution were identified for the study. The treatment targets were classified in three situations which consisted of, the chest wall (CW) only, the chest wall plus supraclavicular lymph nodes (CW + SPC), and the chest wall plus supraclavicular and whole axillary lymph nodes irradiation (CW + SPC+AXLN). The volumetric modulated arc therapy (VMAT) plans and Tomodirect (TD) plans were created for each patient and compared with HT treatment plans which had been treated. The target coverage, dose homogeneity index (HI), conformity index (CI), and dose to OARs were analyzed. The quality scores were used to evaluate the appropriate technique for each situation from multiparameter results.ResultsThe HT and VMAT plans showed the advantage of target coverage and OARs sparing for the chest wall with regional nodal irradiation with the higher plan quality scores when compared with TD plans. However, TD plans demonstrated superiority to contralateral breast sparing for the chest wall without regional nodal situation reaching the highest of planned quality scores. HT plans showed better HI, CI, and target coverage (P < 0.01) than TD and VMAT plans for all patient situations. Volumetric modulated arc therapy plans generated better contralateral breast and heart sparing at a lower dose than HT.ConclusionThe arc‐based techniques, HT and VMAT plans, provided an advantage for complex targets in terms of target coverage and OARs sparing. However, the static beam TD plan was superior for contralateral organ sparing meanwhile achieving good target coverage for the chest wall without regional node situations.

Dosimetric and Radiobiological Comparison of Five Techniques for Postmastectomy Radiotherapy with Simultaneous Integrated Boost.

Purpose To compare five techniques for the postmastectomy radiotherapy (PMRT) with simultaneous integrated boost (SIB). Materials and Methods Twenty patients with left-sided breast cancer were retrospectively selected. Five treatment plans were created for each patient: TomoDirect (TD), unblocked helical TomoTherapy (unb-HT), blocked HT (b-HT), hybrid intensity-modulated radiotherapy (hy-IMRT), and fixed-field IMRT (ff-IMRT). A dose of 50.4 Gy in 28 fractions to PTVtotal and 60.2 Gy in 28 fractions to PTVboost were prescribed. The dosimetric parameters for targets and organs at risk (OARs), the normal tissue complication probability (NTCP), the second cancer complication probability (SCCP) for OARs, and the treatment efficiency were assessed and compared. Results TD plans and hy-IMRT plans had similar good dose coverage and homogeneity for both PTVboost and PTVtotal and superior dose sparing for the lungs and heart. The ff-IMRT plans had similar dosimetric results for the target volumes compared with the TD and hy-IMRT plans, but gave a relatively higher NTCP and SCCP for the lungs. The unb-HT plans exhibited the highest OAR mean dose, highest NTCP for the lungs (0.97 ± 1.25‰) and heart (4.58 ± 3.62%), and highest SCCP for the lungs (3.57 ± 0.05%) and contralateral breast (2.75 ± 0.29%) among all techniques. The b-HT plans significantly outperformed unb-HT plans with respect to the sparing of the lungs and heart. This technique also showed the best conformity index (0.73 ± 0.08) for PTVboost and the optimal NTCP for the lungs (0.03 ± 0.03‰) and heart (0.61 ± 0.73%). Concerning the delivery efficiency, the hy-IMRT and ff-IMRT achieved much higher delivery efficiency compared with TomoTherapy plans. Conclusion Of the five techniques studied, TD and hy-IMRT are considered the preferable options for PMRT with SIB for left-sided breast cancer treatment and can be routinely applied in clinical practice.

Dosimetric comparison of TomoDirect, helical tomotherapy, VMAT, and ff-IMRT for upper thoracic esophageal carcinoma

The new TomoDirect (TD) modality offers a nonrotational option with discrete beam angles. We aim to compare dosimetric parameters of TD, helical tomotherapy (HT), volumetric-modulated arc therapy (VMAT), and fixed-field intensity-modulated radiotherapy (ff-IMRT) for upper thoracic esophageal carcinoma (EC). Twenty patients with cT2-4N0-1M0 upper thoracic esophageal squamous cell carcinoma (ESCC) were enrolled. Four plans were generated using the same dose objectives for each patient: TD, HT, VMAT with a single arc, and ff-IMRT with 5 fields (5F). The prescribed doses were used to deliver 50.4 Gy/28F to the planning target volume (PTV50.4) and then provided a 9 Gy/5F boost to PTV59.4. Dose-volume histogram (DVH) statistics, dose uniformity, and dose homogeneity were analyzed to compare treatment plans. For PTV59.4, the D2, D98, Dmean, and V100% values in HT were significantly lower than other plans (all p < 0.05), and those in TD were significantly lower than VMAT and ff-IMRT (all p < 0.05). However, there was no significant difference in the D2 and Dmean values between VMAT and ff-IMRT techniques (p > 0.05). The homogeneity index (HI) differed significantly for the 4 techniques of TD, HT, VMAT, and ff-IMRT (0.03 ± 0.01, 0.02 ± 0.01, 0.06 ± 0.02, and 0.05 ± 0.01, respectively; p < 0.001). The HI for TD was similar to HT (p = 0.166), and had statistically significant improvement compared to VMAT (p < 0.001) and ff-IMRT (p = 0.003). In comparison with the 4 conformity indices (CIs), there was no significant difference (p > 0.05). For PTV50.4, the D2 and Dmean values in HT were significantly lower than other plans (all p < 0.05), and those in TD were significantly lower than VMAT and ff-IMRT (all p < 0.05). However, there was no significant difference in the D2 and Dmean values between VMAT and ff-IMRT techniques (p > 0.05). No D98 and V100% parameters differed significantly among the 4 treatment types (p > 0.05). HT plans were provided for statistically significant improvement in HI (0.03 ± 0.01) compared to TD plans (0.05 ± 0.01, p = 0.003), VMAT (0.08 ± 0.03, p < 0.001), ff-IMRT (0.08 ± 0.01, p < 0.001). The HI revealed that TD was superior to VMAT and ff-IMRT (p < 0.05). The CI differed significantly for the 4 techniques of TD, HT, VMAT, and ff-IMRT (0.59 ± 0.10, 0.69 ± 0.11, 0.64 ± 0.09, and 0.64 ± 0.11, respectively; p = 0.035). The best CI was yielded by HT. We found no significant difference for the V5, V10, V15, V30, and the mean lung dose (MLD) among the 4 techniques (all p > 0.05). However, the V20 differed significantly among TD, HT, VMAT, and ff-IMRT (21.50 ± 7.20%, 19.50 ± 5.55%, 17.65 ± 5.45%, and 16.35 ± 5.70%, respectively; p = 0.047). Average V20 for the lungs was significantly improved by the TD plans compared to VMAT (p = 0.047), and ff-IMRT (p = 0.008). The V5 value of the lung in TD was 49.30 ± 13.01%, lower than other plans, but there was no significant difference (p > 0.05). The D1 of the spinal cord showed no significant difference among the 4 techniques (p = 0.056). All techniques are able to provide a homogeneous and highly conformal dose distribution. The TD technique is a good option for treating upper thoracic EC involvement. It could achieve optimal low dose to the lungs and spinal cord with acceptable PTV coverage. HT is a good option as it could achieve quality dose conformality and uniformity, while TD generated superior conformality.

Dosimetric evaluation of modern radiation therapy techniques for left breast in deep-inspiration breath-hold

PurposeThe dosimetric differences between four radiation therapy techniques for left sided whole breast irradiation were evaluated side by side in the same patient population. MethodsRadiotherapy treatment plans were retrospectively created with Accuray TomoDirect (TD), Elekta Volumetric Modulated Arc Therapy (E-VMAT), Varian RapidArc (RA) and Field-in-field (FinF) technique for 20 patients, who had received left breast irradiation during deep-inspiration breath-hold. Dose characteristics of planning target volume and organs at risk were compared. ResultsThe E-VMAT, TD and RA treatment plans had higher target coverage (V95%) than FinF plans (97.7–98.3% vs. 96.6%). The low-dose spillage to contralateral breast and lung was smaller with FinF and TD (mean 0.1 and 0.3 Gy) compared to E-VMAT and RA (mean 0.6 and 0.9 Gy). E-VMAT, RA and TD techniques were more effective than FinF in sparing left anterior descending artery (mean 4.0, 4.2 and 4.7 Gy vs. 6.1 Gy, respectively). ConclusionsIn whole breast irradiation TD, E-VMAT and RA plans generated in this study achieved higher dose coverage and sparing of organs from the high dose in the vicinity of the PTV. The advantage of calculated FinF plans is the lowest dose on contralateral organs. The choice of the technique used should be weighted by each institution taking into account the dose characteristics of each technique and its fit with patient anatomy bearing in mind the increased workload of using modulated techniques and the increased beam on time.

Total Body Irradiation Using Fixed-beam Tomotherapy in Patients With Width Larger Than 40cm

To investigate the feasibility of TBI using TomoDirect (TD) for patients with width larger than 40cm and to perform a dosimetric comparison study of treatment plans using Helical Tomotherapy (HT) and TD techniques. 10 TBI patients were selected with median field width in lateral direction of 51.91cm (44.77 cm - 62.89 cm). TBI planning target volume (PTV) was defined as the external body contour minus the bilateral lung expanded by 5 mm. For optimization the lungs were divided into inner (lungs minus 1.5cm), mid lung ring (lungs minus 0.5cm) and outer lung ring (lungs minus mid lung). A virtual bolus was created by expanding the patient’s external contour by 1cm and assigning a density of 0.2 g/cm3. The TBI prescription was at least 80% of the PTV to receive 12 Gy in 6 fractions. For each patient, two treatment plans were generated using both TD, with 8 beam angles, and HT techniques. A dynamic jaw size of 5 cm, a pitch of 0.43, and a modulation factor of 2.0 were used in this study. All other optimization objectives were kept the same for both treatment techniques. The dosimetric evaluation parameters included: PTV mean dose (Dmean), 98% and 95% of PTV dose coverage (D98, D95), homogeneity index (HI), TBI beam-on time and bilateral lungs dose. Student t-test was performed to evaluate the dosimetric differences between TD and HT plans. A p-value of ≤ 0.05was considered significant. Median and ranges for PTV Dmean, D98, D95, HI and beam-on time from TD and HT plans for all ten patients are shown in Table 1.Abstract 3690; Table 1Dmean (Gy)D98 (Gy)D95 (Gy)HITime (minutes)TD12.08(12.01-12.15)10.9(10.6-11.7)11.48(11.25-11.66)0.146(0.03-0.19)22.41(18.27-30.54)HT12.10(12.08-12.23)10.8(9.7-11.5)11.46(10.89-11.65)0.17(0.11-0.28)17.79(14.96-21.49)Significant?NoYesNoYesYes Open table in a new tab Table 1 showed that there was no statistical significant difference between TD and HT techniques for all the patients (n=10) for Dmean and D95. TD plans had better dose coverage of D98 and better HI and longer beam-on times compared to HT plans. For the lung doses, there was a significant difference between HT and TD plans. HT plans spared the lungs better as compared to TD plans, with median dose and ranges of 8.37Gy (7.97Gy to 8.81Gy) for TD plans and 7.93Gy (7.45Gy to 8.26Gy) for HT plans. TD and HT plans were compared for 10 TBI patients. All plans had comparable Dmean and D95 PTV dose coverage and were acceptable for clinical use. However, TD plans had both better D98 dose coverage and dose homogeneity especially for the patients who had more than 50cm width in the lateral direction (7 out of 10 patients). HT treatment plans generally had less beam-on time and spared more lungs as compared to TD plans.

Left-sided breast cancer irradiation using rotational and fixed-field radiotherapy

The 3-dimensional conformal radiotherapy (3DCRT) technique is the standard for breast cancer radiotherapy. During treatment planning, not only the coverage of the planning target volume (PTV) but also the minimization of the dose to critical structures, such as the lung, heart, and contralateral breast tissue, need to be considered. Because of the complexity and variations of patient anatomy, more advanced radiotherapy techniques are sometimes desired to better meet the planning goals. In this study, we evaluated external-beam radiation treatment techniques for left breast cancer using various delivery platforms: fixed-field including TomoDirect (TD), static intensity-modulated radiotherapy (sIMRT), and rotational radiotherapy including Elekta volumetric-modulated arc therapy (VMAT) and tomotherapy helical (TH). A total of 10 patients with left-sided breast cancer who did or did not have positive lymph nodes and were previously treated with 3DCRT/sIMRT to the entire breast were selected, their treatment was planned with Monaco VMAT, TD, and TH. Dosimetric parameters including PTV coverage, organ-at-risk (OAR) sparing, dose-volume histograms, and target minimum/maximum/mean doses were evaluated. It is found that for plans providing comparable PTV coverage, the Elekta VMAT plans were generally more inhomogeneous than the TH and TD plans. For the cases with regional node involvement, the average mean doses administered to the heart were 9.2 (± 5.2) and 8.8 (± 3.0)Gy in the VMAT and TH plans compared with 11.9 (± 6.4) and 11.8 (± 9.2)Gy for the 3DCRT and TD plans, respectively, with slightly higher doses given to the contralateral lung or breast or both. On average, the total monitor units for VMAT plans are 11.6% of those TH plans. Our studies have shown that VMAT and TH plans offer certain dosimetric advantages over fixed-field IMRT plans for advanced breast cancer requiring regional nodal treatment. However, for early-stage breast cancer fixed-field radiotherapy is potentially more beneficial in terms of OAR sparing.

A feasibility study using TomoDirect for craniospinal irradiation

The feasibility of delivering craniospinal irradiation (CSI) with TomoDirect is investigated. A method is proposed to generate TomoDirect plans using standard three‐dimensional (3D) beam arrangements on Tomotherapy with junctioning of these fields to minimize hot or cold spots at the cranial/spinal junction. These plans are evaluated and compared to a helical Tomotherapy and a three‐dimensional conformal therapy (3D CRT) plan delivered on a conventional linear accelerator (linac) for CSI. The comparison shows that a TomoDirect plan with an overlap between the cranial and spinal fields might be preferable over Tomotherapy plans because of decreased low dose to large volumes of normal tissues outside of the planning target volume (PTV). Although the TomoDirect plans were not dosimetrically superior to a 3D CRT linac plan, the patient can be easily treated in the supine position, which is often more comfortable and efficient from an anesthesia standpoint. TomoDirect plans also have only one setup position which obviates the need for matching of fields and feathering of junctions, two issues encountered with conventional 3D CRT plans. TomoDirect plans can be delivered with comparable treatment times to conventional 3D plans and in shorter times than a Tomotherapy plan. In this paper, a method is proposed for creating TomoDirect craniospinal plans, and the dosimetric consequences for choosing different planning parameters are discussed.PACS number: 87.55.D‐

Intensity-modulated radiation therapy using static ports of tomotherapy (TomoDirect): comparison with the TomoHelical mode

PurposeWith the new mode of Tomotherapy, irradiation can be delivered using static ports of the TomoDirect mode. The purpose of this study was to evaluate the characteristics of TomoDirect plans compared to conventional TomoHelical plans.MethodsTomoDirect and TomoHelical plans were compared in 46 patients with a prostate, thoracic wall or lung tumor. The mean target dose was used as the prescription dose. The minimum coverage dose of 95% of the target (D95%), conformity index (CI), uniformity index (UI), dose distribution in organs at risk and treatment time were evaluated. For TomoDirect, 2 to 5 static ports were used depending on the tumor location.ResultsFor the prostate target volume, TomoDirect plans could not reduce the rectal dose and required a longer treatment time than TomoHelical. For the thoracic wall target volume, the V5Gy of the lung or liver was lower in TomoDirect than in TomoHelical (p = 0.02). For the lung target volume, TomoDirect yielded higher CI (p = 0.009) but smaller V5Gy of the lung (p = 0.005) than TomoHelical. Treatment time did not differ significantly between the thoracic wall and lung plans.ConclusionProstate cancers should be treated with the TomoHelical mode. Considering the risk of low-dose radiation to the lung, the TomoDirect mode could be an option for thoracic wall and lung tumors.

Quality assurance of TomoDirect treatment plans using I'mRT MatriXX.

Purpose:To evaluate the performance of 2D-array I’mRT MatriXX for dose verification of TomoDirect treatment plans.Methods:In this study, a 2D-array ion chamber device – the I’mRT MatriXX and Multicube Phantom from IBA – was used for dose verification of different TomoDirect plans. Pre-treatment megavoltage computed tomography (MVCT) was performed on the phantom setup for position correction. After the irradiation of treatment plans on the I’mRT MatriXX and Multicube Phantom, the measured doses of coronal planes were compared with those from the planning calculations for verification. The results were evaluated by comparing the absolute dose difference in the high dose region as well as the gamma analysis of the 2D-dose distributions on the coronal plane. The comparison was then repeated with the measured dose corrected for angular dependence of the MatriXX.Results:When angular dependence is taken into account, the passing rate of gamma analysis is over 90% for all measurements using the MatriXX. If there is no angular dependence correction, the passing rate of gamma analysis worsens for treatment plans with dose contribution from the rear. The passing rate can be as low as 53.55% in extreme cases, i.e. where all doses in the treatment plan are delivered from the rear.Conclusion:It is important to correct the measured dose for angular dependence when verifying TomoDirect treatment plans using the MatriXX. If left uncorrected, a large dose discrepancy may be introduced to the verification results.

SU-E-T-800: Evaluation of Left-Sided Breast Cancer Treatment Using Rotational and Fixed-Gantry Radiotherapy

Purpose: To compare treatment planning for left‐sided breast cancer using the full spectrum of external beam delivery platforms: 3‐dimensional conformal radiotherapy (3DCRT), TomoDirect (TD), fixed‐beam intensity‐modulated radiotherapy(IMRT), and rotational therapy including both volumetric modulated arc therapy (VMAT) and Tomotherapy helical (TH). Methods: Ten left‐sided breast cancer patients with and without positive lymph nodes treated with 3DCRT or fixed‐gantry IMRT to the entire breast were re‐planned with rotational Monaco VMAT, TH and TD. The dosimetric metrics, such as PTV coverage, organ‐at‐risk sparing, DVHs, minimum/maximum/mean doses are evaluated. The VMAT plans were delivered using an Elekta Synergy beam modulator accelerator, the treatment delivery parameters such as the total MUs and delivery time from different techniques are compared. Results: For plans providing comparable PTV coverage, the VMAT plans (HI=1.13) were generally more inhomogeneous than the TH (HI=1.08) and TD (HI=1.04) plans, while TD is less conformal. For the cases with regional node involvement, averaged across the patient, the heart mean doses were 9.2 and 8.8Gy in the VMAT and TH plans, compared to 11.9 and 11.8 Gy for the 3DCRT and TD plans; the mean contra‐lateral lungdoses were 4.4 and 3.2Gy for the VMAT and TH, 3.8 and 1.3Gy for the 3DCRT and TD plans. VMAT plans require shorter delivery time compared to TH. On average, the total MUs for VMAT plans are approximately 11.6% of those TH plans Conclusions: Rotational VMAT and TH offer certain dosimetric advantages over the conventional breast treatment requiring regional nodal coverage at the cost of slightly higher doses to contra‐lateral lung and/or breast. In comparison to TH, VMAT offers more efficiently dosedelivery to achieve comparable dosimetric plans. For early stage breast cancer patients requiring no nodal coverage, 3DCRT and TD are potentially more beneficial in terms of heart, contra‐lateral lung/breast sparing.