[Comparative study on prognostic factors in young and old lung cancer patients under chemo-radiotherapy]

To investigate the differences in prognostic factors between the young and old lung cancer patients treated by chemo-radiotherapy.

The clinical data were collected from 70 young patients (< 40 years old, the study group) and 82 randomly selected old patients (> or = 40 years old, the control group) treated by chemo-radiotherapy. Survival analysis was done by the Kaplan-Meier method, univariate analysis by Log rank test and multivariate analysis by Cox proportional hazard model, respectively.

Median survival time was 10 months in the study group and 12 months in the control group. The 2-year survival rate was 11.1% versus 23.1% and the 5-year survival was 3.1% versus 5.4%, respectively. Univariate analyses demonstrated that symptom duration time, mis-diagnosis duration time, clinical stage, chemo-radiation regimen, radiation dose, DDP dose, weight loss and Karnofsky performance status were associated with the prognosis of the study group, and symptom duration time, clinical stage, radiation dose, DDP dose, weight loss and Karnofsky performance status were associated with that of the control group. Multivariate analyses showed that clinical stage, weight loss and Karnofsky performance status were independent prognostic factors for both groups, but DDP dose only for the study group.

The overall survival was similar in young and old patient groups; There was some difference in prognostic factors between the two groups; DDP dose was an independent prognostic factor for young lung cancer patients which might bear dose-response relationship.