To compare acute and long-term toxicity in prostate cancer patients treated with moderately hypofractionated radiotherapy (MHRT) versus ultra-hypofractionated radiotherapy (UHRT).
Approach:
Study Design: Real-world comparison of toxicity in 229 localized prostate cancer patients treated in Colombia.
Data Comparison: Comparison of findings with the PACE-C trial, which is a phase 3 randomized trial.
Key Findings:
Acute grade >=2 genitourinary toxicity was similar between UHRT and MHRT in the PACE-C trial (28% vs. 27%, p = 0.89).
Cifuentes-Quin et al. reported lower acute toxicity for UHRT compared to MHRT (11.63% vs. 25.17%, p = 0.013).
Late toxicity analysis did not include fractionation schedule, complicating interpretation.
Baseline urinary medication use was imbalanced between groups (18.88% in MHRT vs. 0% in UHRT, p < 0.001).
Sample size was asymmetrical (143 MHRT vs. 86 UHRT), affecting statistical power.
Technical delivery details indicated no fiducial markers were used for UHRT, raising questions about patient selection bias.
Lack of prostate CTV volume data limits interpretation of urinary toxicity outcomes.
ADT use differed between groups (97.20% in MHRT vs. 90.70% in UHRT, p = 0.024), potentially affecting toxicity.
Interpretation:
Observed differences in toxicity may reflect baseline differences between groups rather than the fractionation schedule alone.
Limitations:
Exclusion of fractionation schedule from multivariable analysis of late toxicity.
Statistical model presented as exploratory without validation metrics.
Imbalance in baseline urinary medication use could confound results.
Smaller UHRT cohort limits statistical power and stability of event rates.
Technical delivery methods may introduce selection bias affecting toxicity outcomes.
Lack of prostate CTV volume data complicates understanding of urinary toxicity.
Differences in ADT use could influence urinary and sexual toxicity outcomes.
Conclusion:
The study provides insights into toxicity differences but has limitations that complicate interpretation.
