Administration
of hyperbaric oxygen during radiotherapy for head and neck tumours improved
local tumour control and salvage operation rates, but not survival.
Clinical Bottom Line:
1.
There was no improvement in 5 year survival in the hyperbaric group.
2.
There was significant reduction in the number of patients with local
recurrence in the hyperbaric group.
3.
There was a significant reduction in the number of salvage operations in the
hyperbaric group.
Appraised
by: Mike Bennett, Dept of Diving and
Hyperbaric Medicine, Prince of Wales Hospital, Sydney; Wednesday, 24 February
1999
Clinical
Scenario: A patient presenting with an
SCC of the floor of the mouth for radiotherapy. We asked if the administration
of hyperbaric oxygen during radiotherapy would improve outcome.
Three-part
Question: In patients with head and neck
tumours, does the administration of hyperbaric oxygen during radiotherapy
sessions, compared to normal air breathing, result in any improvement in
survival or local recurrence?
Search
Terms: Hyperbaric oxygenation, tumours/head
and neck.
The
Study:
Non-blinded randomised
controlled trial without intention-to-treat.
Patients with confirmed SCC in
the head and neck in whom radiotherapy was the treatment of choice.
Control group (N = 152; 151
analysed): Radiotherapy to 3,500 rads in 10 fractions over 3 weeks.
Experimental group (N = 143; 125
analysed): Radiotherapy to the same dose schedule but doses given while
breathing oxygen at an unspecified hyperbaric pressure.
The
Evidence:
|
Outcome |
Time
to Outcome |
Air
group |
HBO
group |
Relative
risk reduction |
Absolute
risk reduction |
NNT |
|
survival |
5
years |
0.291 |
0.264 |
9% |
0.027 |
37 |
|
95%
CI: |
|
|
|
-27%
to 46% |
-0.08
to 0.13 |
NNT=8
to INF NNH=13 to
INF |
|
Recurrence
free |
|
.3 |
.53 |
-77% |
-0.230 |
-4 |
|
95%
CI: |
|
|
|
-100%
to -39% |
-0.34
to -0.12 |
-9
to -3 |
|
Salvage
surgery |
|
0.305 |
0.128 |
58% |
0.177 |
6 |
|
95%
CI: |
|
|
|
27%
to 89% |
0.08
to 0.27 |
4
to 12 |
Comments:
1. Large study in this context
has reasonable power to detect a clinically significant difference.
2. HBO seems to save operations
but not lives in this ten fractions regime.
3. There may be little relevance
to the current treatment of these tumours.
4. Those not tolerating HBO (18)
were excluded from analysis.
Expiry date: January 2004
References:
1. Henk JM, Kunkler PB, Smith CW.
Radiotherapy and hyperbaric oxygen in head and neck cancer. Final report of
first controlled clinical trial. Lancet 1977; 8029:101-103.
2. Kunkler PB, Boulis-Wassif S,
Shah NK, Sutherland WH, Smith C. A controlled trial of hyperbaric oxygen in the
radiotherapy of head and neck tumours. Br Journal
of Radiology 1968; 41:557.
3. Henk JM. Overcoming the
oxygen effect: hyperbaric oxygen or protracted fractionation. Fifth
International Hyperbaric Congress Proceedings II 1974:794-801.
4. Henk JM. The influence of
oxygen and hypoxia on laryngeal cancer management. Laryngoscope 1975;
85:1134-1144.
