We have observed increasing rate of patients suffering from multiple primary carcinomas over the last ten years. The aim of this study was to find significant frequencies of various malignant tumour associations, as well as common risk factors, evaluation of therapy, prognosis and survival of patients with confirmed lung cancer and additional primary malignancies. Patients and Methods: This metastudy included 142 patients suffering from more than one primary carcinoma (synchronous or metachronous appearance), where one of the tumours was histopathologically confirmed lung cancer. Patients were registered in our department between 1995 and the fall of 2006. We have analysed their gender, age, family history, smoking status, date of the first malignancy, as well as the timing of the secondary (or tertiary) malignancies. In addition we have observed the most frequent mutual associations of the tumours, outcome of therapy, survival rates, etc. There were 118 men and 24 women, age ranging from 26 to 79 years. The longest interval between each carcinoma diagnoses was 29 years (larynx and lung cancer) and 26 years (malignant lymphoma and lung cancer). The shortest interval corresponded to a simultaneous occurrence of lung cancer duplicity with different morphology. Median time interval between malignant tumours was 3 years. Discussion: In our group predominance of men (83%) is evident, which could be explained by pre-selection of lung carcinoma being more common in men. 84% of patients were smokers (current or former). 50% of patients had positive family history for general cancer occurrence. The mean age of patients at the time of the first carcinoma diagnosis was 59 years, 63 years at second carcinoma and 64 years at a third carcinoma diagnoses. The most common duplicity according together with lung cancer in men was another lung cancer type, while in women it was cervical cancer. Vast majority of patients were smokers (current or former), which corresponds to smoking being an important risk factor in head and neck, larynx, lung, urine bladder, kidney, cervix and colon cancers. In addition, complex genetic factors, such as inherited disease susceptibility though multiple DNA variations seem responsible of frequent positive family history of general cancer occurrence. The role of chemotherapy and radiotherapy in the primary carcinoma treatment should be also considered as an independent risk factor for subsequent malignancies. Conclusion The frequency of multiple carcinomas occurrence is steadily increasing over the past ten years. Paradoxically, gradual improvements in treatment efficiency directed at the primary tumor, gives opportunity for secondary carcinomas to develop. In addition to the possibility of disease relaps it is therefore very important to keep in mind an increased risk of a secondary malignity risk in oncologic patients. This study is further expected to be extended by other common risk analysis – including professional exposure, genetic and dietetics influence as well as other factors.