100 years of lung cancer.

Lung cancer is the most common cause of cancer death in the world. It continues to have an enormous impact on health systems of all countries. The number of new cases is increasing in a rate of about 3% annually. Despite the advances in the detection and treatment of lung cancer, the overall 5-year survival still remains grim. Cigarette smoking remains the major risk factor on the incidence of cancer, with 90% of all lung cancers occurring in smokers. The frequency of different types of lung cancer is changing. Adenocarcinoma has become the most frequent histologic type (approximately 50%) while squamous, previously the most common, accounts for approximately one third of lung cancers, and small cell cancer for 15%. Prognosis is influenced by the stage of the disease at diagnosis and by the treatment. Screening trials that have begun in the early 1950s based on chest X-ray and sputum cytology did not produce improvement in overall mortality. Refinements in the staging classification of lung cancer and advances in stage identification were introduced in the 1990s. Post surgical mortality has declined since the 1950s but the 5-year survival rates have improved only minimally. A gradual improvement is seen in locally advanced inoperable non-small cell lung cancer, mainly due to addition of advanced chemotherapy and radical radiotherapy. Chemotherapy offers small improvement for patients with NSCLC. The management of small cell lung cancer, which appeared so promising in the 1970s has hit a plateau with vary little advance in the last years. The biological active agents currently in phase III trails offer some hope in the advance of therapy of lung cancer. The most important and cost-effective management for lung cancer is smoking cessation, but for those with this disease novel methods of treatment are urgently needed.