The effect of smoking on tumour oxygenation and treatment outcome in cervical cancer.
OBJECTIVE
Tumour hypoxia is associated with an increased risk of cervical tumour recurrence and death. Because smoking is a modifiable behaviour, it is important to establish the importance of smoking as a prognostic factor. We hypothesized that there is an association between smoking and tumour hypoxia, and that smoking adversely affects radiation response and survival.


METHODS
A smoking history was obtained from 100 of 115 patients with cervical cancer entered into a prospective study of tumour oxygenation. Eighty-seven of these had clinically evident disease and radiation therapy alone was the planned treatment. Patients who smoked within 2 weeks of commencing radiation therapy were considered smokers, and the amount that they smoked was recorded in packs per day. Patients who had never smoked or quit at least 2 weeks prior to radiation therapy were considered non-smokers. Tumour oxygenation was determined using the Eppendorf polarographic oxygen electrode and tumour oxygenation is represented by the hypoxic proportion HP5 (% of pO2 measurements <5 mmHg).


RESULTS
There was no significant association between smoking and tumour hypoxia (P=0.3), haemoglobin (P=0.6) nor tumour size (P=0.1). Progression-free survival at 3 years was 56% for non-smokers and 44% for smokers (P=0.23). In both univariate and multivariate analysis, neither smoking status nor amount smoked were significant predictors of progression-free survival or local control.


CONCLUSIONS
There was no significant association between smoking and tumour hypoxia, treatment response or survival in this study of patients with cervix cancer.
Fyles
A
A
Department of Radiation Oncology, Ontario Cancer Institute/Princess Margaret Hospital, University of Toronto, 610 University Avenue, Toronto, Ontario, Canada M5G 2M9. anthony.fyles@rmp.uhn.on.ca
Voduc
D
D
Syed
A
A
Milosevic
M
M
Pintilie
M
M
Hill
R
R
D000328:Adult; D018572:Disease-Free Survival; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D000860:Hypoxia / Q000209:etiology* / Q000473:pathology; D008487:Medical History Taking; D009367:Neoplasm Staging; D010100:Oxygen / Q000032:analysis; D011379:Prognosis; D011446:Prospective Studies; D012907:Smoking / Q000009:adverse effects*; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000473:pathology* / Q000628:therapy
D006454:Hemoglobins; D010100:Oxygen