Background: Acute radiation-induced cystitis is a common side effect of radiation therapy (RT) to the pelvis, with up to 40-50% of prostate cancer patients suffering from cystitis to some extent. Acute symptoms can occur within weeks of radiation treatment and include urinary urgency, frequency, dysuria, and hematuria. Currently there is no effective treatment for radiation cystitis. Here, in a double-blinded pilot study, we investigated the effect of standardised cranberry capsules on the extent of radiation-induced cystitis, and how this impacts on quality of life in prostate cancer patients.
Methodology: A total of 41 men receiving RT for prostate cancer at the Southern Blood and Cancer Center (SBCC) in Dunedin participated in this trial, which opened in May 2012. The men took one capsule a day during breakfast from their first day of treatment until two weeks after completion of treatment. This took place regardless of which arm they were randomised to. Cranberry capsules contained 72mg of proanthocyanidins (PACs) each and were indistinguishable from placebo capsules. Patients, clinicians and research assistants were blinded to the content of the capsules. Severity of cystitis was assessed using a modified urinary domain of the Expanded Prostate Cancer Index Composite (EPIC) scale. Items included severity of symptoms (pain, blood in urine, leakage, urinary frequency in day and night) use of pads and symptomatic relief (URAL), as well as the effect of these symptoms on daily life.
Results: This thesis analysed the results of the first 10 cranberry and 10 control patients who presented with low baseline EPIC scores. The results showed that cranberry capsules seem to decrease certain aspects of radiation cystitis both with regard to physical symptoms and the effect on quality of life. However results in this small cohort did not generally reach statistical significance and limitations of the trial methodology have been recognised.
Conclusion: In light of the limitations of this trial and the positive trends in the results, further investigation is warranted. Future research should focus particularly on establishing consistent hydration levels, regulating the use of symptomatic relief and developing improved methods for assessing the level of acute radiation cystitis.
