Development of GUI-based simple independent dose calculation software without DICOM data transfer for high-dose-rate brachytherapy

Purpose:
Dose calculation in clinical treatment plans must be verified by an independent dose calculation prior to treatment. This study presented an independent second check dose calculation software developed for clinical use.

Material and methods:
A software developed using Python 3 tool on Google Colab platform enabled its deployment on standard computer systems. The software utilized AAPM TG-43 formalism and AAPM consensus dataset for TG-43 parameters, which were consistent with those of a commercial treatment planning system (TPS; Varian Brachy-Vision). As input, the software only used treatment plan report from TPS. Dosimetric comparisons were performed between software-calculated dose at reference points and corresponding TPS values across 117 clinical treatment plans (102 gynecological cases and 15 intra-operative radiation therapy [IORT] cases using high-dose-rate [HDR] brachytherapy). Gynecological cases were categorized into 12 applicator groups, depending on various combination of tandem, ovoids, and needles, and dose calculation points were manually selected close to prescribed dose.

Results:
234 dose points (2 points per plan) were calculated. The dose discrepancy between software and TPS was –1% ±0.36% (mean ± standard deviation), with maximum of –3%. The accuracy of the software met AAPM guideline requirement (< 5% deviation). The simplicity of input file in graphical user interface (GUI) environment enabled the software to operate on any computer without additional software, data transfer, or manual data entry. This capability can be particularly advantageous in IORT procedures, which require quick turn-around second check without network connectivity to TPS for DICOM data transfer.

Conclusions:
A streamlined second check software using TG-43 formalism was developed in Python 3 tool and converted into independent executable GUI, to verify commercial TPS dose calculations in HDR brachytherapy. The software meets current practice guideline and is compatible with commonly used computer systems (Windows, MacOS, and Linux), requiring no additional software, manual data entry, or connection to TPS. The software will also be published online with free public access.