Lung cancer screening and prevention in a still endemic region for granulomatous disease: Brazil
The aim of this article is to give a perspective on how to perform lung cancer screening in places with high incidence of granulomatous diseases (GDs). Regarding improvements in diagnosis and treatments, TB remains one of the major health problems to be faced in Brazil and worldwide. The aspect of the primary complex is the same as that of the indeterminate pulmonary nodule, which may increase the rate of “positive” findings during a screening program. The multidisciplinary team is able to differentiate such nodules from those with greater suspicion, especially when analyzing the whole set of computed tomography (CT) findings associated with the “positive” pulmonary nodule. Considering the lung cancer importance in the depicted epidemiological profile, primary and secondary prevention are fundamental to change the actual scenario. For secondary prevention, periodic lung cancer screening may be useful. In Brazil, there are major concerns that in heavy smokers many benign nodules might be found secondary to GD, leading to unnecessary diagnostic testing and surgical intervention. It is important to emphasize that low-dose CT (LDCT) examinations performed in people from regions with high prevalence of GD may be interpreted by radiologists with experience seeing its most common findings, such as scars at the apex of the lungs, presence of pleural thickening and occurrence of multiple micro nodules. In the experience of our group, with the accomplishment of LDCT screening in about 800 asymptomatic individuals, active tuberculosis (TB) was diagnosed in only three cases, where the radiological suspicion aroused in the absence of significant symptoms. In this scenario, it seems to be feasible to engage asymptomatic high-risk persons for cancer screening in large-scale programs within areas with high prevalence of GDs. Benefits of case-finding in both circumstances of benign transmission able disease or lethal cancer type outweigh most of the harms encountered.