Purposes The main aim of the study was to investigate the dosimetric difference between acuros XB algorithm (AXB), anisotropic analytic algorithm (AAA), and pencil beam convolution (PBC) algorithm in stereotactic body radiation therapy (SBRT) plan for non-small cell lung cancer (NSCLC). Patients and Methods Thirty-eight NSCLC patients were included. GTV, PTV, and organs at risk were delineated by the radiation oncologists. Three optimized SBRT plans for each patients were gained using three algorithms of AXB, AAA, and PBC with the identical plan parameters. Dosimetric endpoints were collected and compared among the three plans, including dosimetric criteria: V100%, V90%, PTV D min , D max , D mean , homogeneity index (HI), and Paddick conformity index (CI). Results AXB plan resulted in decreased V100% with a mean difference 6.14% compared with PBC plan (For V100%, AXB vs AAA vs PBC=93.44% vs 95.54% vs 99.58%, P <0.05). Three plans showed no significant difference as to the parameter V90%. AXB plan leaded to reduced D min of PTV compared with other two algorithms (For D min of PTV, AXB vs AAA vs PBC=4048cGy vs 4365Gy vs 4873Gy, P <0.05). PBC induced the enhanced trend of D max of PTV compared with other two algorithms (D max among three algorithms, P> 0.05); and increased the D mean of PTV in three algorithms with significant difference (For D mean of PTV, AXB vs AAA vs PBC=5332cGy vs 5330Gy vs 5785Gy, P <0.05). AXB algorithm achieved a similar plan conformity with other two algorithms (For CI, AXB vs AAA vs PBC=0.80 vs 0.85 vs 0.71, P >0.05). Conclusion For SBRT plan of NSCLC, AAA and PBC algorithms overestimate target coverage, AXB algorithm is recommended for the SBRT plan of NSCLC.

Whole body exposure from photon-emitting hot particles is receiving new attention because of changes in skin dose regulations. A recent study calculated and tabulated effective dose equivalent (EDE) and effective dose (ED) for photon energies between 0.1 MeV and 2 MeV for point sources at 74 locations on the skin. This technical note describes a software package called the EPRI EDE Calculator that allows a user to input exposure data and to calculate the EDE and ED automatically.

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Objective To investigate the dosimetric impact of different collimator angle optimization methods in intensity‐modulated radiotherapy of gastric cancer. Methods A total of 10 gastric cases were retrospectively selected in this study. Three sets of plans were generated with different collimator angle optimization: setting the collimator angle to 0° (CL0), applying Eclipse automatic collimator angle optimization (CLA), and setting the collimator angle corresponding to the minimum X‐jaw gap (CLX). Different dosimetric metrics were applied in comparison of the target volume and normal tissues. Delivery efficiency was accessed in terms of control points, split fields, monitor units, and treatment time. All plans were verified using the 2‐D array MatriXX, and the γ‐index analysis was carried out by using different criteria. Results There was no significant difference in dosimetric comparison of planning target volume and organs at risk. Compared with CL0, Both CLA and CLX can significantly reduce control points, split fields, and monitor units, except that CLA increased treatment time. For dose verification, the γ passing rate showed a tendency of CLx > CLA > CL0. Conclusion For intensity‐modulated radiotherapy for gastric cancer, CLA and CLX can obtain comparable dosimetry distribution in respect to CL0. However, CLX can significantly increase the dose delivery efficiency and verification passing rates. It was suggested that CLx was beneficial in intensity‐modulated radiotherapy for gastric cancer.