Background: Lung cancer is the leading cause of death among all cancers worldwide. The main risk factors are tobacco smoking as well as occupational risks, radiation, environmental pollutants, etc. According to the international literature, an incidence of 10-40% may be established for epidermal growth factor receptor gene mutation among patients with lung adenocarcinoma. Material and methods: This retrospective study was performed by reviewing all medical records available in the University Hospital “José Eleuterio González” Medical Oncology Service (December 2003 to December 2013). Results: A total of 560 patients diagnosed with pulmonary cancer were identified. Four hundred and twenty six had primary lung tumors. Geographical distribution of the cases was as follows: Nuevo León, 63.8%; Tamaulipas, 20.0%; San Luis Potosí, 12.9%; Zacatecas, 3.2%. Tobacco smoking was identified in 72.8% of cases; 75% of them had a history of more than 20 packs per year. Smoking mean time was 32.8 years. Less than 9% of patients had a history of pneumopathy; 78% had been diagnosed with COPD, 18.9% had a history of pulmonary tuberculosis, and 2.7% had nonspecific pulmonary fibrosis. Fourteen out of 16 cases (38.9%) resulted positive for epidermal growth factor receptor mutation, while only one case was anaplastic lymphoma kinase mutation positive. Conclusion: It is necessary to implement a Mexican cancer registry in order to determine the actual magnitude of and to fully characterize lung cancer in the Mexican population. This study is an effort to describe some features of the disease, but it is not yet enough to establish the prevalence of common mutations, so compilation of data will still be mandatory.