Randomised phase II trial of hyperbaric oxygen therapy in patients with chronic arm lymphoedema after radiotherapy for cancer

Background: a non-randomised phase II study suggested a therapeutic effect of hyperbaric oxygen (HBO) therapy on arm lymphoedema following adjuvant radiotherapy for early breast cancer, justifying further investigation in a randomised trial.Methods: fifty-eight patients with ?15% increase in arm volume after supraclavicular ± axillary radiotherapy (axillary surgery in 52/58 patients) were randomised in a 2:1 ratio to HBO (n = 38) or to best standard care (n = 20). The HBO group breathed 100% oxygen at 2.4 atmospheres absolute for 100 min on 30 occasions over 6 weeks. Primary endpoint was ipsilateral limb volume expressed as a percentage of contralateral limb volume. Secondary endpoints included fractional removal rate of radioisotopic tracer from the arm, extracellular water content, patient self-assessments and UK SF-36 Health Survey Questionnaire.Findings: of 53/58 (91.4%) patients with baseline assessments, 46 had 12-month assessments (86.8%). Median volume of ipsilateral limb (relative to contralateral) at baseline was 133.5% (IQR 126.0–152.3%) in the control group, and 135.5% (IQR 126.5–146.0%) in the treatment group. Twelve months after baseline the median (IQR) volume of the ipsilateral limb was 131.2% (IQR 122.7–151.5%) in the control group and 133.5% (IQR 122.3–144.9%) in the treatment group. Results for the secondary endpoints were similar between randomised groups.Interpretation: no evidence has been found of a beneficial effect of HBO in the treatment of arm lymphoedema following primary surgery and adjuvant radiotherapy for early breast cance