Hyperbaric
oxygen during radiotherapy did not improve survival rates for patients with
advanced carcinoma of the uterine cervix.
Clinical Bottom Line:
1.
Hyperbaric oxygen during radiotherapy did not improve survival at 27
months for patients with advanced carcinoma of the uterine cervix.
2.
There was some evidence of improved local tumour control.
Appraised
by: Mike Bennett, Dept of Diving and
Hyperbaric Medicine, Prince of Wales Hospital
Sydney; Monday, 22 March 1999
Clinical
Scenario: A patient with cervical cancer
presented for radiotherapy. We wondered if there was any indication for
hyperbaric oxygen.
Three-part
Question: For patients with Stage III and
IV cancer of the uterine cervix, does the addition of hyperbaric oxygenation
during radiotherapy result in any improvement in survival?
Search
Terms: Cervix neoplasms, Radiotherapy
The
Study:
Non-blinded concealed randomised
controlled trial without intention-to-treat.
Patients with Stage IIIA and B,
or Stage IV cancer of the uterine cervix in whom radiotherapy was indicated.
Control group (N = 23; 23
analysed): Radiotherapy in twenty-four fractions over 6 weeks with a dose of 250
rads/day. Some variation in protocols. No sham treatment.
Experimental group (N = 17; 17
analysed): Dosing schedule started identical to the above, but reduced 7% after
the first 7 patients. Treatment undertaken while breathing 100% oxygen at 3ATA,
total chamber time about 40 mins.
The
Evidence:
|
Outcome |
Time to
Outcome |
Air group |
HBO group |
Relative
risk reduction |
Absolute
risk reduction |
NNT |
|
Death |
27 months |
0.61 |
0.53 |
13% |
0.08 |
13 |
|
95% CI: |
|
|
|
-38% to 64% |
-0.23 to 0.39 |
NNT=3 to INF
NNH=4 to INF |
|
Dead with
local disease |
27 months |
0.478 |
0.235 |
51% |
0.243 |
4 |
|
95% CI: |
|
|
|
-9% to 100% |
-0.044 to 0.530 |
NNT=2 to INF
NNH=23 to INF |
Comments:
1. Protocol for irradiation in
hyperbaric patients changed due to unacceptable rate of complications.
2. Patients were not analysed by
intention to treat and the fate of those excluded from analysis is not known.
(Accounts for different group sizes).
Expiry
date:
January
2004
References:
1.
Faust DS, Brady LW, Kazem I, Germon PA. Hybaroxia and radiation therapy
in carcinoma of the cervix (stage III and IV): a clinical trial. In: Proceedings
of Fourth International Hyperbaric Congress, Igaku Shoin, Tokyo 1969:410-414.
2.
Glassburn JR, Damsker JI, Brady LW, Faust DS, Antoniades J, Prasavinichai
S, Lewis GC, Torpie RJ, Asbell SO. Hyperbaric oxygen and radiation treatment of
advanced cervical cancer. Proceedings of the Fifth International Hyperbaric
Congress. Simon Fraser University 1974; II:813-819.
