Objective: Our objectives were (1) to examine tumor oxygenation measured with an Eppendorf pO(2) histograph, prior to and during carbogen (95% oxygen, 5% carbon dioxide) breathing in patients with primary cervical cancer; and (2) to assess the feasibility of delivering external beam radiation therapy and concurrent carbogen to patients treated for cervical cancer.
Methods: Pretreatment tumoral pO(2) measurements were obtained using an Eppendorf pO(2) histograph in patients with primary cervical cancers while breathing room air and after 4 min of carbogen breathing. Patients able to tolerate the carbogen inhalation were asked to inhale it for 4 min prior to and during all external beam radiation therapy.
Results: Two sets of pO(2) measurements were obtained from 25 patients. The average median pO(2) increased from 8 mm Hg when breathing room air to 96 mm Hg after carbogen breathing. Twenty-four of 25 patients tolerated the carbogen; they inhaled carbogen during their daily external beam radiation therapy. All 24 patients completed their planned course of external beam radiation therapy and daily concurrent carbogen without significant difficulty.
Conclusion: (1) Carbogen inhalation increased the average median pO(2) value 10-fold and decreased the percentage of values </=2.5 and 5 mm Hg. (2) Carbogen inhalation is feasible during external beam pelvic radiation.
Copyright 1999 Academic Press.