Radiotherapy quality assurance for the PEACE 1 trial: An individual case review analysis

Area of Science:

• Oncology
• Radiation Oncology
• Clinical Trials

Background:

• Radiotherapy quality assurance (RTQA) is critical for maintaining protocol compliance in clinical trials.
• The PEACE-1 trial evaluated standard of care with or without docetaxel, local radiotherapy, and abiraterone acetate plus prednisone in metastatic hormone-sensitive prostate cancer (mHSPC).

Purpose of the Study:

• To summarize the results of individual case reviews (ICRs) for radiotherapy quality assurance in the PEACE-1 trial.
• To assess the adherence to protocol for target volume and organs at risk delineation and dose specifications.

Main Methods:

• Central review of radiotherapy plans submitted by participating institutions.
• Individual case reviews (ICRs) conducted retrospectively (r-ICRs) or prospectively (p-ICRs).
• Categorization of reviews as acceptable, acceptable variation, or unacceptable variation based on delineation and dose parameters.

Main Results:

• Out of 585 patients, 527 (90%) underwent r-ICRs, predominantly using intensity-modulated radiotherapy (IMRT).
• Delineation review approved 87% of r-ICRs and 92% of p-ICRs, with common errors in clinical target volume (CTV) delineation.
• Dose and plan reviews showed high approval rates (96% for both r-ICRs and p-ICRs), with issues mainly related to planning target volume (PTV) dose distribution.

Conclusions:

• RTQA is essential in prostate cancer trials, particularly for accurate target volume delineation.
• Retrospective ICRs (r-ICRs) are resource-intensive and recommended to be omitted.
• Limited prospective ICRs (p-ICRs) with early feedback are suggested, reserving full p-ICRs for novel techniques or dose regimens.