Is sex associated with the outcome of patients treated with radiation for nonsmall cell lung cancer?

BACKGROUND

Lung cancer is the leading cause of cancer death for both men and women, but the disease course differs between the sexes. To the authors' knowledge, sex-based differences in outcomes among the population of nonsmall cell lung cancer (NSCLC) patients receiving radiation have not been well defined.

METHODS

Data for 831 patients (319 women and 512 men) with stage I to III NSCLC and treated with > or =45 Gray of radiation between March 1985 and November 2003 were retrospectively analyzed (grading determined according to the 1997 American Joint Committee on Cancer grading system).

RESULTS

Women were more likely to have earlier stage disease, to have smoked <50 pack-years, and to have adenocarcinoma or large-cell carcinoma (all P < or = .001). For each stage, treatment did not differ between women and men. Five-year survival rates were significantly better for women than for men: overall survival (OS), 28.6% versus 16.1% (P < .001); disease-free survival, 31.2% versus 20.1% (P = .02); and distant metastasis-free survival, 48.8% versus 37.6% (P < .02). Among patients with medically inoperable stage I NSCLC, women had improved 5-year OS compared with men (30.0% vs 13.1%; P = .004). On multivariate analysis, male sex, weight loss, age > or =65 years, and stage III disease were found to be associated with poorer OS (all P < 0.02).

CONCLUSIONS

Although women are more likely to have earlier stage disease, among patients with medically inoperable stage I NSCLC, women still have a better OS. Along with known prognostic factors, including age, weight loss, and stage, sex remained significant on multivariate analysis of OS, suggesting that sex is a determinant of outcome in NSCLC patients receiving radiation.