A VMAT planning solution for prostate patients using a commercial treatment planning system

Area of Science:

• Radiation Oncology
• Medical Physics

Background:

• Volumetric modulated arc therapy (VMAT) is an advanced radiation delivery technique offering potential advantages over traditional fixed-beam intensity-modulated radiation therapy (IMRT).
• Commercial VMAT planning systems exist, but in-house solutions allow for greater control and detailed investigation of planning processes.

Purpose of the Study:

• To describe the development and validation of an in-house single-arc VMAT planning method for prostate cancer using an existing treatment planning system.
• To compare the dosimetric and delivery characteristics of the developed VMAT technique against a standard IMRT approach.

Main Methods:

• Utilized Philips Pinnacle(3) v.8.0 TPS supplemented by in-house software for VMAT plan generation.
• Initiated planning with static IMRT segments, modified them, and sequenced into a single 360-degree arc with 60 control points.
• Conducted dose-volume histogram analysis and dosimetric verification, resilience, and repeatability tests.

Main Results:

• VMAT plans achieved dose-level target coverage comparable to standard IMRT.
• VMAT demonstrated superior sparing of critical organs at risk, specifically the rectum and bladder.
• Treatment delivery times were significantly reduced using the VMAT method.

Conclusions:

• The developed in-house VMAT planning solution provides a robust and effective alternative for prostate cancer treatment.
• This method achieves comparable target coverage to IMRT while enhancing organ-at-risk sparing and treatment efficiency.
• The approach is validated through dosimetric verification, showing resilience and repeatability.