Seasonal and geographical variations in lung cancer prognosis in Norway. Does Vitamin D from the sun play a role?

Porojnicu AC, Robsahm TE, Dahlback A, Berg JP, Christiani D, Bruland OS, Moan J. Seasonal and geographical variations in lung cancer prognosis in Norway. Does Vitamin D from the sun play a role? Lung Cancer 2007; 55(3):263-270.