Rate of delivery of hyperbaric oxygen treatments does not affect response in soft tissue radionecrosis.

BACKGROUND Soft tissue radiation necrosis (STRN) is effectively treated with hyperbaric oxygen (HBO,), believed to result from stimulation ofangiogenesis in radiation-injured tissue. Thirty to forty HBO2 treatments are usually recommended for STRN. For various reasons, different hyperbaric facilities offer these treatments once or twice daily and from 5-7 days weekly. It is not known whether the clinical response differs as a result of the rate of administration of HBO2 treatments. METHODS Details of hyperbaric treatment courses of patients treated for radiation enteritis/proctitis (n = 65) and cystitis (n = 94) at a single institution were reviewed. Outcomes were compared with the total number of HBO2 treatments administered and also rate of treatment administration. RESULTS Responses were similar for both forms of STRN whether the patient averaged fewer or greater than 5 treatments per week, or even < or = 3 versus > or = 7 treatments weekly. Outcome did differ, however, dependant on the total number of treatments administered. Response was better in patients receiving 30 or more total treatments, as compared with fewer. CONCLUSIONS Soft tissue radionecrosis of the gastrointestinal tract or bladder is (1) effectively treated with hyperbaric oxygen, (2) has a higher response rate if at least 30 treatments are administered, and (3) is equally responsive to rates of hyperbaric treatment ranging from 3 or fewer to 7 or more treatments per week.