Administration
of hyperbaric oxygen during radiotherapy for carcinoma of the uterine cervix did
not improve survival rate at a minimum of 2 years.
Clinical Bottom Line:
1.
There was no evidence of an improvement in survival rate with the simultaneous
administration of hyperbaric oxygen during radiotherapy for carcinoma of the
uterine cervix.
2.
There was no evidence of increased complications in the hyperbaric oxygen
group.
Appraised
by: Mike Bennett, Dept of Diving and
Hyperbaric Oxygen, Prince of Wales Hospital, Sydney; Monday, 22 March 1999
Clinical
Scenario: A patient with advanced
carcinoma of the uterine cervix presented for radiotherapy. We wondered if the
administration of hyperbaric oxygen at the time of radiotherapy would improve
survival or local recurrence rates.
Three-part
Question: In patients with advanced
carcinoma of the uterine cervix where radiotherapy is the treatment of choice,
does the simultaneous administration of hyperbaric oxygen as compared to
radiotherapy in air, result in any improvement in survival or local recurrence
rate?
Search
Terms: Cervix, neoplasms
The
Study:
Non-blinded concealed randomised
controlled trial without intention-to-treat.
Patients with Stage IIB to IVA
cancer of the uterine cervix, aged under 70 years. They underwent a complex
staging protocol and were stratified for stage prior to randomisation.
Control group (N = 124; 124
analysed): Radiotherapy fields and dose were varied by extent of involvement and
given in a standard 5 fractions/week schedule over 4 to 5 weeks. More advanced
cases received implanted radium in addition. No sham treatment.
Experimental group (N = 109; 109
analysed): Radiotherapy schedule as above, but undertaken while breathing 100%
oxygen at 3ATA, exact profile not given but 20 minute soak period prior to
radiotherapy.
The
Evidence:
|
Outcome |
Time
to Outcome |
Air
group |
HBO
group |
Relative
benefit increase |
Absolute
benefit increase |
NNT |
|
Survival
with no evidence of disease |
Min
2 years |
0.411 |
0.330 |
20% |
0.081 |
12 |
|
95%
CI: |
|
|
|
-10%
to 50% |
-0.043
to 0.205 |
NNT=5
to INF NNH=23 to
INF |
Comments:
1. Failure rate of local control
was reported as unaffected by hyperbaric oxygen, although figures not given.
2. This trial studied the effect
of hyperbaric oxygen in a conventional dosing schedule.
Expiry
date:
January
2004
References:
1. Fletcher GH, Lindberg RD, Caderao JB,
Wharton JT. Hyperbaric oxygen as a radiotherapeutic adjuvant in advanced cancer
of the uterine cervix. Preliminary results of a randomised trial. Cancer 1977;
39:617-623.
2. Lindberg RD, Fletcher GH,
Caderao JB. Present status of high-pressure oxygen in radiotherapy. Proceedings
of the XIII International Congress of Radiology. Amsterdam Excerpta Medica 1973;
1:665-670.
3. Fletcher GH, Lindberg RD,
Caderao JB, Wharton JT. The preliminary results of a randomised trial of
patients with late stage cancer of the uterine cervix using hyperbaric tank or
atmospheric oxygen. Proceedings of the American Radium Society 1975;341-346.
