Late rectal and bladder toxicity following radiation therapy for prostate cancer: Predictive factors and treatment results

Aim: This study aimed at investigating factors associated to late rectal and bladder toxicity following radiation therapy and the effectiveness of Hyperbaric Oxygen Therapy (HBOT) when toxicity is grade >= 2. Background: Radiation is frequently used for prostate cancer, but a 5-20% incidence of late radiation proctitis and cystitis exists. Some clinical and dosimetric factors have been defined without a full agreement. For patients diagnosed of late chronic proctitis and/or cystitis grade >= 2 treatment is not well defined. Hyperbaric Oxygen Therapy (HBOT) has been used, but its effectiveness is not well known. Materials and methods: 257 patients were treated with radiation therapy for prostate cancer. Clinical, pharmacological and dosimetric parameters were collected. Patients having a grade >= 2 toxicity were treated with HBOT. Results of the intervention were measured by monitoring toxicity by Common Toxicity Criteria v3 (CTCv3). Results: Late rectal toxicity was related to the volume irradiated, i.e. V50 > 53.64 (p = 0.013); V60 > 38.59% (p = 0.005); V65 > 31.09% (p = 0.002) and V70 > 22.81% (p = 0.012). We could not correlate the volume for bladder. A total of 24 (9.3%) patients experienced a grade >= 2. Only the use of dicumarinic treatment was significant for late rectal toxicity (p = 0.014). A total of 14 patients needed HBOT. Final percentage of patients with a persistent toxicity grade >= 2 was 4.5%. Conclusion: Rectal volume irradiated and dicumarinic treatment were associated to late rectal/bladder toxicity. When toxicity grade >= 2 is diagnosed, HBOT significantly ameliorate symptoms. (C) 2013 Greater Poland Cancer Centre. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.