A Mayo Clinic study has found that overall quality of life (QOL) measured at the time of a non-small cell lung cancer (NSCLC) diagnosis appears to significantly and independently predict survival. For patients with poor baseline QOL, the average survival was 1.6 years, compared with 5.6 years for those with strong QOL measures at diagnosis. The following were also significantly associated with overall survival among patients with NSCLC:

Performance status.
Older age.
Smoking history
Male gender
Treatment factors
Disease stage.

Abstract: Journal of Clinical Oncology, March 26, 2012 (online).