Sause
Irradiation of head and neck squamous cell carcinomas while breathing hyperbaric oxygen was not associated with improved outcomes.
| Clinical Bottom Line: |
| 1. The two regimes tested produced comparable survival, local control of tumour and complication rates. |
Appraised by: Mike Bennett, Dept of Diving and Hyperbaric Medicine, Prince of Wales Hospital Sydney; Thursday, 18 February, 1999
Clinical Scenario: A patient with a squamous cell carcinoma (SCC) of the tongue presented for radiotherapy. Three-part Question: In treatment of SCC of the head and neck, does irradiation in a hyperbaric oxygen chamber, compared to in air, result in improved survival or fewer side-effects? Search Terms: Hyperbaric oxygenation, tumour/head and neck
The Study: Non-blinded randomised controlled trial with intention-to-treat. Patients with SCCs of the head and neck referred for radiotherapy. Control group (N = 23; 23 analysed): Radiotherapy four days each week for approximately six weeks, to a total dose of 6,250 rads in air. Experimental group (N = 21; 21 analysed): Radiotherapy 2.5 times each week for approximately five weeks to 4,800 rads total dose while breathing oxygen at three atmospheres. Ret dose slightly lower than air group.
The Evidence:
| Outcome | Time to Outcome | Air group | HBO group | Relative risk reduction | Absolute risk reduction | NNT |
| Local recurrence | 2 years | 0.44 | 0.38 | 12% | 0.05 | 19 |
| 95% CI: | -54% to 79% | -0.24 to 0.34 | NNT3 to INF NNH4 to INF | |||
| Death | 2 years | 0.48 | 0.43 | 9% | 0.05 | 20 |
| 95% CI: | -47% to 66% | -0.25 to 0.34 | NNT3 to INF NNH4 to INF | |||
| Treatment complications | 2 years | 0.217 | 0.190 | 12% | 0.03 | 37 |
| 95% CI: | -97% to 100% | -0.21 to 0.27 | NNT4 to INF NNH5 to INF |
Comments: 1. Six patients were excluded after randomisation, 5 because of early death from intercurrent disease. 2. Treatment tested was HBO and a shorter radiotherapy regime with fewer fractions. 3. Relevance to practice today is unclear.
Expiry date: July 2020 References: 1. Sause WT, Plenk HP. Radiation therapy of head and neck tumours: a randomised study of treatment in air vs. treatment in hyperbaric oxygen. International Journal of Radiation Oncology, Biology and Physics 1979; 5:1833-1836.
