Purpose: The purpose of this study was to develop a predictive model to evaluate pretreatment patient-specific quality assurance (QA) based on treatment planning parameters for stereotactic body radiation therapy (SBRT) for liver carcinoma. Materials and Methods: We retrospectively selected 180 cases of liver SBRT treated using the volumetric modulated arc therapy technique. Numerous parameters defining the plan complexity were calculated from the DICOM-RP (Radiotherapy Plan) file using an in-house program developed in MATLAB. Patient-specific QA was performed with global gamma evaluation criteria of 2%/2 mm and 3%/3 mm in a relative mode using the Octavius two-dimensional detector array. Various statistical tests and multivariate predictive models were evaluated. Results: The leaf speed (MILS) and planning target volume size showed the highest correlation with the gamma criteria of 2%/2 mm and 3%/3 mm (P < 0.05). Degree of modulation (DoM), MCSSPORT, leaf speed (MILS), and gantry speed (MIGS) were predictors of global gamma pass rate (GPR) for 2%/2 mm (G22), whereas DoM, MCSSPORT, leaf speed (MILS) and robust decision making were predictors of the global GPR criterion of 3%/3 mm (G33). The variance inflation factor values of all predictors were <2, indicating that the data were not associated with each other. For the G22 prediction, the sensitivity and specificity of the model were 75.0% and 75.0%, respectively, whereas, for G33 prediction, the sensitivity and specificity of the model were 74.9% and 85.7%%, respectively. Conclusions: The model was potentially beneficial as an easy alternative to pretreatment QA in predicting the uncertainty in plan deliverability at the planning stage and could help reduce resources in busy clinics.

Background: Stereotactic ablative body radiation (SABR) is a well-recognized treatment option for hepatocellular carcinoma (HCC). Due to the inherent motion of liver tumors, effective motion management is crucial for successful SABR. In the motion-encompassing motion management technique, all 10 respiratory phase image datasets are delineated and designated as the internal target volume (ITV). Some treatment centers use single or combination image sets to delineate the target volume. This study determines which specialty image set most closely matches an all-phase ITV contour on a synchronized contrast-enhanced 4DCT. Materials and methods: Synchronized 4DCT contrast and delayed scans were acquired for 10 patients in the study. The maximum intensity projection (MiP), average intensity projection (AvgIP), and minimum intensity projection (MinIP) images were generated. The ITV delineation was done in all 10 phases (ITV_all_phase). The ITV_2phase combines the peak inhale and exhale phase, ITV_2 M combines MiP and MinIP, and ITV_3 M combines MiP, MinIP, and AvgIP. All ITVs were compared to ITV_all_phase with Dice similarity index (DSI) and volumes. Results: Using ITV_all_phase as the reference, the DSI and the mean ITV volumes for the different ITVs were as follows: ITV_all_phase (1 and 116.69 cc), ITV_2phase (0.87 and 105.27 cc), MiP (0.76 and 98.24 cc), AvgIP (0.72 and 94.54 cc), ITV_MinIP (0.67 and 81.08 cc), ITV_2 M (0.84 and 106.26 cc), and ITV_3 M (0.86 and 112.51 cc). Conclusion: The study demonstrates that in the motion-encompassing technique of motion management, the target volume generated by delineating all phases of 4DCT provides the most accurate representation for patients with HCC. Specialty image sets and their combinations, while sometimes close, tend to result in less accurate targeting. Hence,the all-phase 4DCT method should be preferred to avoid geographical misses and ensure optimal treatment outcomes. However, our conclusion may be limited by the technique we employed.

Purpose: The purpose of the study was to analyze and estimate planning risk volume (PRV) margin for heart in deep inspiration breath hold (DIBH)-based left breast radiotherapy. Materials and Methods: Fifty left-sided cancer breast cases treated with volumetric modulated arc radiotherapy were included in this retrospective study. Treatment plans were created using the Eclipse treatment planning system from Varian Medical System. The treatment was delivered on TrueBeam linear accelerator (Varian). Onboard cone-beam computed tomography (CBCT) images were generated and image registration between the planning computed tomography images and the CBCT images was performed before treatment delivery. The registration provided the shifts (errors) values in 6° of freedom, namely three translational and three rotational. From the shift values, the systematic and random errors were estimated which were used to estimate PRV margin for the heart after incorporating the rotational errors with the translational errors. Results: The systematic error values after incorporating rotational errors with translational errors were 0.13 cm (lateral) and 0.11 cm (cranio caudal [CC] and anterioposterior each), and the random error values were 0.16 cm (lateral) and 0.13 cm (CC and anterioposterior each). Based on these values, the PRV margins for the heart in all three directions were 0.24 cm (lateral), 0.20 cm (CC), and 0.19 cm (anterioposterior). Conclusion: As per our institutional practice, the 2 mm value for PRV margin for the heart in all the three directions would suffice for appropriate sparing of the heart during DIBH-based radiation therapy.

INTRODUCTION:To evaluate the role of stereotactic body radiotherapy (SBRT) in hepatocellular carcinoma (HCC) patients with inferior vena cava tumour thrombus (IVCTT) who are not suitable for other loco-regional therapies.METHODS:This is an observational retrospective study done between May 2020 and April 2022. The data of 17 patients who underwent SBRT were collected. Patients of Child-Pugh score (CPS) A5-B7 and along with a liver reserve of ≥700 cc were included. Local control (LC), overall survival (OS) and adverse events including hepatic decompensation were carefully recorded.RESULTS:In the cohort, the tumour thrombus was extended to the right atrium in nine (52.9%) patients, and regional nodal and lung were found in 60% and 31.4% of patients respectively. The median gross tumour volume (GTV) was 745 cc (107-1,650 cc). The median SBRT dose prescription was 35 Gy (25-45 Gy) in 5-10 fractions. At 6 months, LC and OS were 80% and 75% respectively. On multivariate analysis, an ALBI score >-2.36 was found to be the predictor for the poor OS. Post-SBRT, a change in CPs by 2 points was observed in one patient (5.9%) which was managed conservatively. Post-radiation, improvement in pain and discomfort was observed in 92.3% and 87% of patients, respectively and bone metastasis related pain was also resolved.CONCLUSION:Stereotactic body radiotherapy is a safe and feasible option for HCC patients with IVC and right atrium tumour thrombosis. It not only improves the quality of life but also results in good LC and OS with acceptable toxicity. SBRT should be considered in a multidisciplinary fashion for patients presenting with tumour thrombosis extending to IVC and the right atrium.

To evaluate the role of palliative stereotactic body radiation therapy (SBRT) in Barcelona Clinic Liver Cancer stage‑C (BCLC-C) hepatocellular carcinoma (HCC) patients who are not suitable for other loco-regional therapies. It is an observational retrospective study done between May 2020 and September 2021. The data were collected from 35 patients of advanced HCC who underwent SBRT. Patients of Child Pugh status (CPs) A5-B7 and with a liver reserve of ≥ 700cc were included. Local control (LC), overall survival (OS) and adverse events including decompensation were carefully recorded. In the cohort, Portal vein and IVC tumor thrombosis were present in 33 (94.3

Introduction. This study aimed to analyze the degree of reduction in normal liver complication probability (NTCP) from free-breathing (FB) to breath-hold (BH) liver SBRT. The effect of the radiation dose-volume on the mean liver dose (MLD) was also analyzed due to dose prescription, normal liver volume (NLV), and PTV.Materials and Methods. Thirty-three stereotactic body radiation therapy (SBRT) cases of hepatocellular carcinoma were selected, retrospectively. For FB, the treatments were planned on average intensity projection scan (CTavg), and patient-specific internal target volume (ITV) margins were applied. To simulate the BH treatment, computed tomography (CT) scan correspond to the 40%-50% of the respiratory cycle (CT40%-50%) was chosen, and an appropriate intrafraction margin of 2 mm, 1.5 mm, and 1.5 mm were given in craniocaudal (CC), superior-inferior (SI), and lateral direction to generate the final iGTV. As per RTOG 1112, all organs at risk (OAR's) were considered during the optimization of treatment plans. NTCP was calculated using LKB fractionated model. Multivariate regression analysis was performed to see the effect of EQD2Gy, NLV, and PTV on MLD2Gy.Results.A significant dosimetric difference was observed in the normal liver (liver-ITV/iGTV). A reduction of 1.7% in NTCP was observed from FB to BH technique. The leverage of dose escalation is more in BH because MLD2Gycorresponds to 5%, 10%, 20%, and 50% NTCP was 0.099 Gy, 0.41 Gy, 1.21 Gy, and 3.432 Gy more in BH as compared to FB technique. In MVRA, the major factor which was attributed to a change in MLD2Gyis EQD2Gy. Conclusion. From FB to BH technique, a significant reduction in NTCP was observed. The dose prescription is a major factor attributed to the change in MLD2Gy. Advances in knowledge: If feasible, prefer BH treatment either for tumor dose escalation or for the reduction in NTCP.

Recently, the Barcelona Clinic Liver Cancer (BCLC) group has updated its recommendation for the management of hepatocellular carcinoma (HCC) to emphasize personalized treatment.1 One major change in the BCLC 22 update is the incorporation of “treatment stage migration (TSM)” defined as upstaging of patient profile leading to shifting of recommendation to the option that would be considered for more advanced stage. It is surprising that in the present update, external beam radiation therapy (EBRT) has not been included in the treatment algorithm. Various studies have been published that have demonstrated the safety and efficacy of EBRT such as stereotactic body radiation therapy (SBRT) and proton therapy in BCLC AB HCC.2 Mathew et al have demonstrated 1-, 3and 5-year overall survival (OS) of 77·3%, 39·0%, and 24·1%, respectively, in 297 patients (pts) with 436 HCCs. BCLC-C group includes both pts with macrovascular invasion and those with extrahepatic metastasis. Studies have shown improved survival with SBRT in pts withmacrovascular invasionwho are not fit for other modalities of local treatment.3 The study by Collen et al in patients with synchronous oligometastatic—non small cell lung cancer (NSCLC) patients treated with SBRT had demonstrated a median overall survival (mOS) of 23months.4 Similarly, SBRT can be considered to be the primary lesion along with oligometastatic sites in HCC resulting in improved quality of life and extending survival.5 Choi et al has reported mOS of 13.3 months in pts with Hep B-related BCLC-C group of patients.6 Evolving evidence has also suggested that concurrent use of immunotherapywith SBRT (SBRT-IO) has resulted inmore powerful immune activation effects. In a study by Chiang et al, the overall response rate (ORR) was 87.5% (CR: 50%, PR: 37.5%) in the SBRT-IO arm as compared with 17% (CR: 2.4%, PR: 14.3%) in the TACE alone group. Similarly, the 12 months OS was 93.8% versus 80.4%, respectively.7 EBRThas been included as one of the treatment options in a selected group of population with HCC by the National Comprehensive Cancer Network (NCCN), American Association for the Study of Liver Diseases (AASLD).8,9 Recently the American Society for Radiation Oncology (ASTRO) has also recommended the use of EBRT in HCC. As per guidelines, radiation therapy can be used as a first-line option in patientswith early disease not amenable to other local therapies. Further ASTRO has also recommended RT to consolidate other local therapies after incomplete response or recurrence. In the BCLC-C group of the population, it can be used with palliative intent.10 In conclusion, evidence is available for the use of EBRT in all stages of BCLC, especially in patients with progressive or metastatic disease but more randomized prospective trials results are required. We do hope that in future updates of BCLC guidelines, incorporation of EBRTwill be considered as a treatment option for patients with HCC.

Background: Many staging systems of Hepatocellular Carcinoma (HCC) are established, however, there is no consensus on most reliable scoring system for predicting prognosis in locoregional advanced HCC patients treated with Stereotactic Body radiation Therapy (SBRT) . Aim: To compare the validity of six prognostic staging systems, as well as to identify the staging system with the best prognostic value in HCC patients treated with SBRT. Methods: It is an observational retrospective study done between May 2020 and April 2021. The data were collected from 26 patients with locoregional advanced HCC who were unsuitable for other liver-directed therapies. Patients with Child pugh score A5-B7 along with normal liver reserve ≥ 700cc were included. All patients were classified before SBRT by the following scoring systems: AJCC 2017 TNM staging system, ALBI, ALBI-T, GLETCH, Chinese University Prognostic Index (CUPI), Advanced Liver Cancer Prognostic System (ALCPS). Cumulative survival rates were calculated using the Kaplan-Meier method and were compared using the log-rank test. Results: In this cohort, 92.3% patients had Portal vein tumor thrombosis (PVTT). Lung and nodal metastasis were found in 39% and 62% patients respectively. The 6 months and 1 year survival rates were 85% and 35%, respectively. The overall median survival time was 9 months. Of the studied different scoring systems for prognosis: TNM staging system (AJCC 2017), CUPI score, ALBI score, ALBI-T score were found to be statistically significant with P value 0.038, 0.001, 0.003 and 0.002, respectively except GRETCH score (P=0.397) and ALCPS (P=0.108). Conclusion: Among the different prognosis evaluating scoring systems in patients with locoregional advanced Hepatocellular Carcinoma undergoing SBRT TNM, CUPI, ALBI and ALBI-T scores are found to be more reliable.

Background: Commercial treatment planning system (TPS) does not have any tool to provide the quantitative analysis of DVH bands (corresponding to each delineated structure) in a radiotherapy treatment plan (RTP). The proposed study reveals the design and algorithm of an in-house developed "DVH Analyzer" tool that provides quantitative analysis of DVH bands. Further, the clinical use of this tool demonstrated with the use of four different clinical cases. Methods: DVH bands for each of the delineated structures in different RTPs generated using the "Plan Uncertainty Parameters" (PUP) module in the TPS by simulating different patient setup errors (PSE) in iso-center of the base plan in x-, y-, and z-directions. DVH bands were exported from the TPS and imported into the DVH Analyzer for processing, analysis, and plotting through various modules. Results: Various user-defined volumetric and dosimetric parameters were calculated from DVH bands of each of the delineated structures in different RTPs. The impact of PSE on the user-defined parameters was also analyzed and graphically demonstrated for different clinical sites. Conclusions: The unique feature of DVH Analyzer to handle DVH bands provides a quantitative and qualitative evaluation of the robust RTPs generated with different PSE. The flexibility in design and implementation of DVH Analyzer makes it a promising tool for the clinics that could be utilized for clinical evaluation of robust treatment plans.

BACKGROUND:A purpose of the study was to investigate the dosimetric impact of contrast media on dose calculation using average 4D contrast-enhanced computed tomography (4D-CECT) and delayed 4D-CT (d4D-CT) images caused by CT simulation contrast agents for stereotactic body radiation therapy (SBRT) of liver cases.MATERIALS AND METHODS:Fifteen patients of liver SBRT treated using the volumetric modulated arc therapy (VMAT) technique were selected retrospectively. 4D-CECT, and d4D-CT were acquired with the Anzai gating system and GE CT. For all patients, gross target volume (GTV) was contoured on the ten phases after rigid registration of both the contrast and delayed scans and merged to generate internal target volume (ITV) on average CT images. Region of interest (ROI) was drawn on contrast images and then copied to the delayed images after rigid registration of two average CT datasets. The treatment plans were generated for contrast enhanced average CT, delayed average CT and contrast enhanced average CT with electron density of the heart overridden.RESULTS:No significant dosimetric difference was observed in plans parameters (mean HU value of the liver, total monitor units, total control points, degree of modulation and average segment area) except mean HU value of the aorta amongst the three arms. All the OARs were evaluated and resulted in statistically insignificant variation (p > 0.05) using one way ANOVA analysis.CONCLUSIONS:Contrast enhanced 4D-CT is advantageous in accurate delineation of tumors and assessing accurate ITV. The treatment plans generated on average 4D-CECT and average d4D-CT have a clinically insignificant effect on dosimetric parameters.

Introduction. The present study aims to investigate the dosimetric and radiobiological impact of patient setup errors (PSE) on the target and organs at risk (OAR) of the cervix carcinoma stage IIB patients treated with volumetric-modulated arc therapy (VMAT) delivery technique using plan uncertainty parameters module of Varian Eclipse treatment planning system and in-house developed DVH Analyzer program.Materials and Methods. A total of 976 VMAT plans were generated to simulate the PSE in the base plan that varies from -10 mm to 10 mm in a step size of 1 mm in x- (lateral), y- (craniocaudal), and z- (anteroposterior) directions. The different OAR and tumor (PTV) volumes were delineated in each case. Various plan quality metrics, such as conformity index (CI) and homogeneity index (HI), as well as radiobiological quantities, such as tumor control probability (TCP) and normal tissue control probability (NTCP), were calculated from the DVH bands generated from the cohort of treatment plans associated with each patient case, using an in-house developed 'DVH Analyzer' program. The extracted parameters were statistically analyzed and compared with the base plan's dosimetric parameters having no PSE.Results. The maximum variation of (i) 2.4%, 21.5%, 0.8%, 2.5% in D2ccof bladder, rectum, small bowel and sigmoid colon respectively; (ii) 19.3% and 18.9% in Dmaxof the left and right femoral heads (iii) 16.9% in D95%of PTV (iv) 12.1% in NTCP of sigmoid colon were observed with change of PSE in all directions. TCP was found to be considerably affected for PSEs larger than 4 mm in x+, y+, z+directions and 7 mm in x-, y-and z-directions, respectively.Conclusion. This study presents the effect of PSE on TCP and NTCP for the cervix carcinoma cases treated with VMAT technique and also recommends daily image guidance to mitigate the effects of PSE.

Objective: This study presents a methodology for voxel based evaluation of two phase sequential radiotherapy treatment plans having conventional dose scheme in the first phase and subsequent hypofractionation dose scheme in the second phase based upon different priority [planning target volume (PTV), clinical target volume (CTV) and organs at risk (OAR)] of display modes. Methods: A case of carcinoma prostate was selected for demonstration. Varian Eclipse treatment planning system (TPS) was used for contouring and planning. In the first phase, a dose of 52Gy in 26 fractions to the PTV and in the second phase, a dose of 19.5Gy in 3 fractions to the PTV Boost was planned on the same CT data set. Both the plans (Phase 1 and Phase 2) were exported and processed using "Voxel-based radiobiology display (VRb) tool". Plan Sum for Biologically effective dose (BED)-Cube and equivalent dose of 2Gy (EQD(2))-Cube was reconstructed using a combination of linear quadratic (LQ) and linear quadratic-linear (LQ-L) radiobiological models. Tumor control probability (TCP) and normal tissue complication probability (NTCP) for different target volumes and organs were also calculated using EQD(2)-volume histograms of the Plan Sum. Results: An in-house graphical user interface (GUI) is developed to present the qualitative and quantitative evaluation of the multiphase treatment plans with different display modes and dose regimens. The voxel based TCP obtained for the combined target volume was 90.56%. NTCP for the bladder and rectum was calculated from the Plan Sum histograms and found to be 0,33% and -0.0% respectively. Conclusion: The proposed methodology using the VRb tool offers superior plan evaluation for multiphase sequential radiotherapy treatment plans over the existing methods. Advances in knowledge: PTV, CTV and OAR priority based display modes in VRb tool offers better understanding of radiobiological evaluation of sequential radiotherapy treatment plans.

Background The purpose of this study was to evaluate the outcome of stereotactic body radiation therapy (SBRT) in patients of unresectable hepatocellular carcinoma (HCC ) complicated with portal vein tumor thrombosis (PVTT) who are also unsuitable for other locoregional therapies. Materials and methods Between May 2018 and January 2020, twenty-nine patients with advanced unresectable HCC s, treated with SBRT, were enrolled in this retrospective audit. Patients of Child status A5–B7 and with healthy liver volume, ≥ 700 ccs were treated. Local control (LC), overall survival (OS), progression-free survival (PFS), PVTT opening rate, and effect of prognostic factors were analyzed. Results The median tumor diameter was 8.6 cm (5–14), and the median tumor volume was 275 cc (151–1196). The median SBRT dose prescription was 48 Gy in 6 fractions (32–50 Gy in 5–6 fractions). The median follow up was eight months (1–20), 1-year local control, progression-free survival, and overall survival were 95%, 53.4%, and 60%, respectively. Overall rate of grade III toxicity was less than 5%, and the most common toxicity was lymphocytopenia. Tumors of more than 350cc had worse OS and PFS when compared to tumors < 350 cc (median OS and PFS of tumors > 350 cc was 4 months and two months, p = .01 and .003, respectively). A total of fifteen patients progressed with the disease and the median time to progression was two months [1–4]. Conclusion SBRT is safe and provides excellent local control in advanced HCC complicated with PVTT. The out of field failure pattern and time to failure in these patients highlights the need for adjuvant systemic therapy after completion of local treatment. Our data warrant the need for multimodality trials in this patient cohort.

Aim: Development of bidirectional non-monotonic segmented leaf sequence (NSLS) MLC delivery technique compatible with Varian MLC for non-split IMRT fields reducing total monitor units (TotaIMU) and the number of segments (NS) simultaneously and assessment of its efficiency using a plan scoring index (PSI). Materials and methods: The optimal fluence of IMRT plans of ten patients of lung carcinoma, calculated using Eclipse TPS version 11.0 (Varian Medical Systems, Palo Alto, CA, USA), was used to generate the segmented MLC fields using our newly developed equally spaced (ES) reducing level and NSLS algorithms in MATLAB (R) version 2011b for 6-10 intensity levels. These MLC fields were imported into the plans with the same field setup and the final dose was recalculated. The results were compared with those of commercially available multiple static segments (MSS) leaf motion calculation (LMC) algorithm and few previously published algorithms. Plan scoring index (PSI) and degree of modulation (DoM) was calculated to compare the quality of different plans for the same patient. Results: The average differences in TotaIMU and NS with respect to MSS algorithm are -3.80% and -14.28% for the NSLS algorithm, respectively. The calculated average PSI and DoM is 0.75, 2.51 and 0.91, 2.41 for the MSS and NSLS algorithms, respectively. Conclusions: IMRT plans generated using the NSLS algorithm resulted in the best PSI, DoM values among all the leaf sequencing algorithms. Our proposed NSLS algorithm allows bidirectional delivery in Varian medical linear accelerator which is not commercially available. NSLS algorithm is efficient in reducing the TotaIMU and NS with equivalent plan quality as that of MSS. (C) 2020 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights reserved.

Aim: The aim is a dosimetric comparison of dynamic conformal arc integrated with the segment shape optimization and variable dose rate (DCA_SSO_VDR) versus VMAT for liver SBRT and interaction of various treatment plan quality indices with PTV and degree of modulation (DoM) for both techniques. Background: The DCA is the state-of-the-art technique but overall inferior to VMAT, and the DCA_SSO_VDR technique was not studied for liver SBRT. Materials and methods: Twenty-five patients of liver SBRT treated using the VMAT technique were selected. DCA_SSO_VDR treatment plans were also generated for all patients in Monaco TPS using the same objective constraint template and treatment planning parameters as used for the VMAT technique. For comparison purpose, organs at risk (OARs) doses and treatment plans quality indices, such as maximum dose of PTV (D-max%), mean dose of PTV (D-mean%), maximum dose at 2 cm in any direction from the PTV (D-2cm%), total monitor units (MU's), gradient index R-50%, degree of modulation (DoM), conformity index (CI), homogeneity index (HI), and healthy tissue mean dose (HTMD) were compared. Results: Significant dosimetric differences were observed in several OARs doses and lowered in VMAT plans. The D-2(cm)%, R-50(%), CI, HI and HTMD are dosimetrically inferior in DCA_SSO_VDR plans. The higher DoM results in poor dose gradient and better dose gradient for DCA_SSO_VDR and VMAT treatment plans, respectively. Conclusions: For liver SBRT, DCA_SSO_VDR treatment plans are neither dosimetrically superior nor better alternative to the VMAT delivery technique. A reduction of 69.75% MU was observed in DCA_SSO_VDR treatment plans. For the large size of PTV and high DoM, DCA_SSO_VDR treatment plans result in poorer quality. (C) 2020 Greater Poland Cancer Centre. Published by Elsevier B.V. All rights reserved.

Objective:The development of a stringent derivative-based gamma (DBG) index for patient-specific QA in stereotactic radiotherapy treatment planning (SRTP) to account for the spatial change in dose.Methods:Twenty-five patients of liver SBRT were selected retrospectively for this study. Deliberately, two different kinds of treatment planning approaches were used for each patient. Firstly, the treatment plans were generated using a conventional treatment planning (CTP) approach in which the target was covered with a homogeneous dose along with the nominal dose fall-off around the treatment field. Subsequently, the other treatment plans were generated using an SRTP approach with the intent of heterogeneous dose within the target region along with a steeper dose gradient outside the treatment field as much as possible. For both kinds of treatment plans, two dimensional (2D) conventional gamma (CG) and DBG analysis were performed using the 2D ion chamber array and radiochromic film.Results:Difference in the DBG index was statistically significant whereas, for CG analysis, the difference in CG index was insignificant for both types of treatment plans (CTP and SRTP). A significant positive correlation was observed between the difference in the DBG index and the difference in HI for high gamma criteria.Conclusion:The DBG evaluation is found to be more rigorous, and sensitive to the only SRTP. The proposed method could be opted-in the routine clinical practice in addition to CG.Advances in knowledge:DBG is more sensitive to detect the spatial change of dose, especially in high dose gradient regions.