The so-called pulmonary hamartomas occur in 0.3% of the general population, with a higher frequency in male gender and in the sixth decade of life. Usually they are single lesions peripherally located in the lung, are formed by mature lobular cartilage and less frequently show adipous and fibromixoid tissue, also with calcified foci. These tumors should be called benign mesenchymomas, due to studies that showed cromossomic alterations and genetic translocations, whose malignant potential has not been recognized.