Introduction:
Anti-tobacco interventions have been effective in many developed countries where lung and other tobacco-related cancers are declining. In Turkey, the first tobacco legislation put into practice in 1996 and strengthened in 2008. Aim of this work was to quantify the size of the problem in each of the seven geographical regions and in the whole of Turkey.

Methods:
We followed the methods proposed by Peto et al.(Lancet 339, 1992) and Parkin et al.(Int. J Cancer 59,1994). Incidence rates of lung and other tobacco-related cancers were obtained from CI5C vol.XI for 8 provinces and projected to the regions. Estimates of the incidence of lung cancer in non-smokers and relative risks for the other cancer sites were obtained from the large CPS II cohort of the American Cancer Society. By combining these parameters in the usual formula due to Cole&MacMahon we obtained estimates of the fraction of tobacco-related cancer attributable to smoking (PAF).

Results:
For Turkey, in total, 59.4% of the 351591 TRC cases can be attributed to tobacco smoking; 74.5% in males, 6.8% in females. PAFs by cancer sites are as follow: 89.6%, 38.4% of lung; 86.4%, 5.1% of laryngeal; 70.3%, 4.3% of oesophagial; 70.5%, 3.1% of oral-cavity&pharyngeal; 54.4%, 0.4 % of kidney; 53.2%, 1.7% of bladder; 38.4%, 1.1% of stomach, 39.1%, 1.1% of liver, 41.3%, 1.5 % of the pancreas cancers and 30.4%, 0.5% of myeloid leukemias in men and women respectively; 1.03 % of cervical cancers in women. The highest PAF for all TRCs is in Marmara (81.9%) where the lowest in Eastern and Southeastern Anatolia region (58.0%) in men, and in Mediterranean (10.4%), in Western Black Sea region (0.0%) respectively in women .

Conclusions:
More than half of all TRCs in Turkey is due to tobacco smoking. Implemented tobacco control programs should be strengthened.