Incidence of lung cancer in Denmark: historical and actual status.

This is a registry-based analysis of 97,281 lung cancer patients diagnosed in Denmark during the period 1943-1994. The development of lung cancer incidence in Denmark in the study period is described and this information is used to predict the future trends in lung cancer in Denmark. Since 1960, lung cancer has been the most frequent type of cancer in Danish men, excluding skin cancer. The incidence in men reached its maximum in 1985, when it was 100 new cases per 100,000 inhabitants, whereafter the incidence began to level off and was 83 per 100,000 inhabitants in 1994. During the study period, the incidence of lung cancer in Danish women was somewhat lower than in men. The incidence in women has been steadily increasing since 1960 by approximately 20% per each 5-year period, and was 46 per 100,000 inhabitants in 1994. Adenocarcinoma is the most frequent histological subtype in women and the only subtype increasing in incidence in men. Taking the actual development into account, the incidence of lung cancer will continue to fall among men and rise among women, leading to a reversal of the classical gender ratio in about 15 years.