['To determine the relationships between tumor oxygenation and nodal stage in a prospective study of patients with cervix cancer, controlling for other prognostic factors.', 'Between 1994 and 1999, 128 eligible patients with cervix cancer were entered into a prospective study of tumor oxygenation assessed by Eppendorf oxygen electrode before primary radiation therapy. Oxygenation was evaluated using the proportion of pO(2) values < 5 mmHg (HP(5)), and tumors were classified as hypoxic if the HP(5) was > 50%. Patients were assigned to one of three groups: those with no imaging evidence of nodal (pelvic or para-aortic) or distant metastatic disease (N group; n = 67), those with equivocal findings (E group; n = 28), and those with nodal or distant metastatic disease (P group; n = 33).', 'The proportion of hypoxic tumors in the P, E, and N groups were 67%, 50%, and 40%, respectively (p = 0.014), with median HP(5) values of 63%, 48%, and 36%, respectively (p = 0.0024). In a multivariate analysis including tumor size, stage, HP(5), and hemoglobin, it was found that tumor size and HP(5) were the only independently significant variables for the finding of metastatic disease (p = 0.009 and 0.017, respectively).'] Are tumor size and oxygenation independent predictors of nodal diseases in patients with cervix cancer?