scholarly journals Can the Student Outperform the Master? A Plan Comparison Between Pinnacle Auto-Planning and Eclipse knowledge-Based RapidPlan Following a Prostate-Bed Plan Competition

2019 ◽  
Vol 18 ◽  
pp. 153303381985176 ◽  
Author(s):  
April Smith ◽  
Andrew Granatowicz ◽  
Cole Stoltenberg ◽  
Shuo Wang ◽  
Xiaoying Liang ◽  
...  

Purpose: Pinnacle Auto-Planning and Eclipse RapidPlan are 2 major commercial automated planning engines that are fundamentally different: Auto-Planning mimics real planners in the iterative optimization, while RapidPlan generates static dose objectives from estimations predicted based on a prior knowledge base. This study objectively compared their performances on intensity-modulated radiotherapy planning for prostate fossa and lymphatics adopting the plan quality metric used in the 2011 American Association of Medical Dosimetrists Plan Challenge. Methods: All plans used an identical intensity-modulated radiotherapy beam setup and a simultaneous integrated boost prescription (68 Gy/56 Gy to prostate fossa/lymphatics). Auto-Planning was used to retrospectively plan on 20 patients, which were subsequently employed as the library to build an RapidPlan model. To compare the 2 engines’ performances, a test set including 10 patients and the Plan Challenge patient was planned by both Auto-Planning (master) and RapidPlan (student) without manual intervention except for a common dose normalization and evaluated using the plan quality metric that included 14 quantitative submetrics ranging over target coverage, spillage, and organ at risk doses. Plan quality metric scores were compared between the Auto-Planning and RapidPlan plans using the Mann-Whitney U test. Results: There was no significant difference between the overall performance of the 2 engines on the 11 test cases ( P = .509). Among the 14 submetrics, Auto-Planning and RapidPlan showed no significant difference on most submetrics except for 2. On the Plan Challenge case, Auto-Planning scored 129.9 and RapidPlan scored 130.3 out of 150, as compared with the average score of 116.9 ± 16.4 (range: 58.2-142.5) among the 125 Plan Challenge participants. Conclusion: Using an innovative study design, an objective comparison has been conducted between 2 major commercial automated inverse planning engines. The 2 engines performed comparably with each other and both yielded plans at par with average human planners. Using a constant-performing planner (Auto-Planning) to train and to compare, RapidPlan was found to yield plans no better than but as good as its library plans.

2019 ◽  
Vol 05 (01) ◽  
pp. 24-33
Author(s):  
Manindra Bhushan ◽  
Girigesh Yadav ◽  
Deepak Tripathi ◽  
Lalit Kumar ◽  
Abhinav Dewan ◽  
...  

Abstract Introduction To evaluate the dosimetric effect of photon energies on fixed field intensity-modulated radiotherapy (IMRT) and dual arc (DA) planning and to compare the dosimetric differences between conventional IMRT and DA radiotherapy planning. Materials and Methods IMRT and DA plans were generated for 15 patients having cervical cancer using different photon energies. IMRT and DA plans were generated using seven fields and double arcs, respectively. Dosimetric comparison was done in terms of planning target volume (PTV) coverage, sparing of organ at risk (OAR), homogeneity index (HI), conformity index (CI), and monitor units (MUs). Photo-neutron (energy ≤10MV) contribution was not considered for this study. Near region (NR) and far region (FR) were contoured to evaluate the dose deposited in nontarget area. Results No significant difference was observed (p > 0.05) in PTV coverage for conventional IMRT and DA; however, 6 MV yielded significantly better coverage over 15 MV (p < 0.05) for both the treatment modalities. Mean bladder dose was significantly more for conventional IMRT compared with DA. For rectal mean dose, p-value was nonsignificant for IMRT in comparison to DA, while significant difference was observed for change in photon energies for both treatment modalities respectively, except for 10 MV versus 15 MV DA plans. Significant improvements in HI (except 6 MV vs. 10 MV DA), CI (except 6 MV vs. 10 MV IMRT and DA), MUs, NR, and FR were noted. Conclusion DA generates more conformal, homogenous plans, requires less numbers of MUs, and deposits fewer doses to NR and FR regions of nontarget tissues in comparison to conventional IMRT. Although increase in photon energy for IMRT and DA plans reduces numbers of MUs and dose deposited to NR and FR regions, yet the choice for treatment of carcinoma cervix remains 6 MV due to production of photo-neutrons at higher energies.


2008 ◽  
Vol 7 (2) ◽  
pp. 77-88 ◽  
Author(s):  
Anup Kumar Bhardwaj ◽  
T.S. Kehwar ◽  
S.K. Chakarvarti ◽  
Goda Jayant Sastri ◽  
A.S. Oinam ◽  
...  

AbstractInter-observer variations in contouring and their impacts on dosimetric and radiobiological parameters in intensity-modulated radiotherapy (IMRT) treatment for localised prostate cancer patients were investigated. Four observers delineated the gross tumour volume (GTV) (prostate and seminal vesicles), bladder and rectum for nine patients. Contouring done by radiologist was considered as gold standard for comparison purposes and for IMRT plan optimisation. Maximum average variations in contoured prostate, bladder and rectum volumes were 3% (SD = 8.4), 2.5% (SD = 4.12) and 13.2% (SD = 6.77), respectively. The average conformity index for standard contouring set (observer A) was 0.85 (SD = 0.028) and statistically significant differences were observed for observers A–B (p = 0.008), A–C (p = 0.006) and A–D (p = 0.011). Average values of normal tissue complication probability for bladder and rectum for observer A were 0.361% (SD = 0.036) and 1.59% (SD = 0.14). Maximum average tumour control probability was 99.94% (SD = 0.035) and statistically significant difference was observed for observers A–B (p = 0.037) and observers A–C (p = 0.01). Inter-observer contouring variations have significant impact on dosimetric and radiobiological outcome in IMRT treatment planning. So accurate contouring of tumour and normal organs is a fundamental prerequisite to make good correlation between calculated and clinical observed results.


2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Vincent Wing Cheung Wu ◽  
Man In Pun ◽  
Cho Pan Lam ◽  
To Wing Mok ◽  
Wah Wai Mok

This study compared the performance of volumetric modulated arc therapy (VMAT) techniques: single arc volumetric modulated arc therapy (SA-VMAT) and double arc volumetric modulated arc therapy (DA-VMAT) with the static beam conventional intensity modulated radiotherapy (C-IMRT) for non-small-cell lung carcinoma (NSCLC). Twelve stage I and II NSCLC patients were recruited and their planning CT with contoured planning target volume (PTV) and organs at risk (OARs) was used for planning. Using the same dose constraints and planning objectives, the C-IMRT, SA-VMAT, and DA-VMAT plans were optimized. C-IMRT consisted of 7 static beams, while SA-VMAT and DA-VMAT plans consisted of one and two full gantry rotations, respectively. No significant difference was found among the three techniques in target homogeneity and conformity. Mean lung dose in C-IMRT plan was significantly lower than that in DA-VMAT plan P=0.04. The ability of OAR sparing was similar among the three techniques, with no significant difference in V20, V10, or V5 of normal lungs, spinal cord, and heart. Less MUs were required in SA-VMAT and DA-VMAT. Besides, SA-VMAT required the shortest beam on time among the three techniques. In treatment of early stage NSCLC, no significant dosimetric superiority was shown by the VMAT techniques over C-IMRT and DA-VMAT over SA-VMAT.


2020 ◽  
Vol 27 (1) ◽  
pp. 107327482090470
Author(s):  
Chen-Hsi Hsieh ◽  
Pei-Wei Shueng ◽  
Li-Ying Wang ◽  
Li-Jen Liao ◽  
Wu-Chia Lo ◽  
...  

This study aimed to review clinical experiences using whole-field simultaneous integrated boost (SIB) intensity-modulated radiotherapy (IMRT) and sequential IMRT in postoperative patients with oral cavity cancer (OCC). From November 2006 to December 2014, a total of 182 postoperative patients with OCC who underwent either SIB-IMRT (n = 63) or sequential IMRT (n = 119) were enrolled retrospectively and matched randomly according to multiple risk factors by a computer. The differences were well balanced after patient matching ( P = .38). The median follow-up time was 65 months. For patients treated with the SIB technique and the sequential technique, the respective mortality rates were 36.8% and 20.0% ( P = .04). The primary recurrence rates were 26.3% and 10.0% ( P = .02), respectively. The respective marginal failure rates were 26.7% and 16.7%. A multivariate logistic regression analysis showed that patients who received the SIB technique had a 2.74 times higher risk of death than those who received the sequential technique (95% confidence interval = 1.10-6.79, P = .03). Sequential IMRT provided a significantly lower dose to the esophagus (5.2 Gy, P = .02) and trachea (4.6 Gy, P = .03) than SIB-IMRT. For patients with locally advanced OCC, postoperative sequential IMRT may overcome an unpredictable geographic miss, potentially with a lower marginal failure rate in the primary area. Patients treated by sequential IMRT show equal overall survival benefits to those treated by SIB-IMRT and a lower mortality rate than those treated by SIB-IMRT. Additionally, a reduced dose to the esophagus and trachea compared to sequential IMRT was noted.


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