Comparing the safety outcomes between proton beam therapy vs intensity-modulated radiation therapy in early stage prostate cancer

This study compared the safety outcomes between moderately-hypofractionated intensity-modulated radiation therapy (IMRT) and proton beam therapy (PBT) in patients with early-stage prostate cancer. The data showed that both treatments were safe and well-tolerated.

Radiation therapy (RT) is a treatment used for low- or intermediate-risk prostate cancer (PCa). This can include proton beam therapy or intensity-modulated radiation therapy.

Proton beam therapy (PBT) is a type of radiation therapy that uses a beam of special particles, called protons, instead of X-rays to destroy cancer cells. PBT delivers the high-energy more precisely to the cancer cells and less to the surrounding healthy tissues such as the bladder and genitals. Moderately-hypofractionated intensity-modulated radiation therapy (IMRT) is an advanced type of high-precision RT. It uses X-ray beams to target and destroy the prostate tumor. IMRT involves a shorter course of treatment (4-6 weeks) with larger doses of radiation delivered in each treatment. There are very few studies comparing the safety outcomes of the 2 treatments in patients with early-stage PCa.

This study involved 1850 patients with low- to intermediate-risk PCa. Patients were put into 2 groups. Group 1 included 1282 patients who received IMRT. Group 2 included 568 patients who received PBT. The average follow-up period was 80 months for the IMRT group and 43.9 months for the PBT group.

Overall, 56.6% of all patients did not experience any late genitourinary (GU; genitals and urinary organs) toxic effects. 74.4% of patients did not have any late gastrointestinal (GI) side-effects. No significant differences in the late toxicity were seen between the 2 treatment groups.

This study showed that both IMRT and PBT were safe and resulted in low rates of toxicity in early-stage PCa.

The study was conducted at multiple single institutions. Patient-reported quality of life outcome data is missing.