Thirty-nine patients, 35 men and 4 women with a mean age of 71 (range, 35-84) years were included after informed consent and institutional ethics approval. They had all been treated with radiation therapy for prostate (n=34), cervix (n=2), or rectal (n=3) cancer using external beam radiation at a dose of 25 to 75 Gy. Patients with hematuria requiring blood transfusion were excluded. The HBOT was delivered with 100 % oxygen for 90 minutes at 2.0 to 2.4 atmospheres (ATA). Mean number of treatments was 36 (28-40). Symptoms were prospectively assessed using the Expanded Prostate Index Composite score before, during, and 6 to 12 months after HBOT.
The HBOT was successfully conducted, and symptoms were alleviated in 76 % for patients with radiation cystitis, 89 % for patients with radiation proctitis, and 88 % of patients with combined cystitis and proctitis. Symptom reduction was demonstrated by an increased Expanded Prostate Index Composite score in the urinary domain from 50 ¡À 16 to 66 ¡À 20 after treatment (P<.001) and in the bowel domain from 48 ¡À 18 to 68 ¡À 18 after treatment (P<.001). For 31 % of the patients with cystitis and 22 % with proctitis, there were only trivial symptoms after HBOT. The improvement was sustained at follow-up in both domains 6 to 12 months after HBOT. No severe side effects were observed related to HBOT, and treatment compliance was high.
HBOT can be an effective and safe treatment modality for late radiation therapy-induced soft tissue injuries in the pelvic region.