Prevalence of the Rhesus-negative phenotype in Caucasian patients with small-cell lung cancer (SCLC).

We report that the Rhesus (Rh)-negative phenotype is more prevalent in patients with small-cell lung cancer (SCLC) than in the normal Caucasian population (SCLC: 25% Rh-negative vs. 15% expected, p less than 0.0001). This finding has been validated for a Central and a Northern European population (Switzerland and UK). In contrast, the Rh-negative phenotype is no more frequent in non-small-cell lung cancer patients or in heavy smokers with coronary heart disease than in the general population. There was a normal distribution of the ABO blood group phenotype in all patients studied. Whilst the significance of this observation is unclear, we hypothesize that a genetic predisposition to the development of SCLC may be linked to a hitherto unidentified gene on chromosome 1p near the Rh locus. Our observation may perhaps allow further progress to be made in understanding genetic mechanisms of SCLC carcinogenesis.