In clinical lung cancer studies, patients with comorbidities often are excluded, leading to a
lack of information about the potential effect of comorbidity on survival, quality of life, or the possible interactions of the
therapeutic agents on the comorbidity itself. One reason may be that there is no consensus on how to assess comorbidity or the impact of comorbidity on disease course or survival. Diabetes mellitus is the most prevalent endocrine disorder and the incidence is increasing. Results from studies on the impact of diabetes mellitus on lung cancer prognosis are
to date conflicting. One report showed an increased survival,
three authors referred no change in survival8–10 and two
studies showed decreased survival11,12 (Table 1). Diabetes
mellitus has been reported to be associated with increased
mortality in cancers of colon, pancreas, endometrium, liver,
and breast.13–16 Another concern is how targeted therapy like
insulin-like growth factor-1 receptor (IGF-1R) inhibitor may
influence the prognosis in patients with lung cancer with
diabetes mellitus. The aim of the present study was to analyze
the impact of diabetes mellitus on survival in patients with
lung cancer in a large Norwegian cohort study.