SU-E-T-216: TPS QC Supporting Program by a Third-Party Evaluation Agency in Japan

Area of Science:

• Medical Physics
• Radiation Oncology
• Quality Assurance

Background:

• Ensuring consistent radiation therapy quality across Japan is crucial.
• Quality control (QA) and quality assurance (QA) of treatment planning systems (TPS) are essential for accurate radiation delivery.

Purpose of the Study:

• To support quality control of radiation treatment planning systems (TPS) in Japan.
• To assess the proper commissioning, implementation, and application of TPS in cancer core hospitals.

Main Methods:

• A questionnaire was distributed to 45 prefectural cancer core hospitals to collect TPS beam data.
• Data included calculations for MUs, doses at various depths, and factors like output, wedge, and TMR for different field sizes.
• 179 beam data sets from 44 facilities were collected and analyzed.

Main Results:

• Analysis of 179 beam data sets from 44 facilities was performed.
• Data comparison focused on dose per MU, output factor, wedge factor, and TMR.
• A significant finding was that 90% of the collected TPS data agreed within a 2% tolerance.

Conclusions:

• The quality of TPS in Japanese cancer core hospitals was evaluated using essential beam data.
• The study demonstrated good agreement among 90% of the 179 beam data sets analyzed.
• This indicates a generally high standard of TPS quality control in the participating facilities.