Challenges of Implementing Lung Cancer Screening in a Developing Country: Results of the Second Brazilian Early Lung Cancer Screening Trial (BRELT2).

PURPOSE: This paper aims to present the results of a series of several Brazilian institutions that have been carrying out lung cancer screening (LCS). MATERIALS AND METHODS: This is a retrospective, cohort study, with follow-up of individuals of both sexes, with a heavy smoking history, who participated in LCS programs between December 2013 and January 2021 in six Brazilian institutions located in the states of São Paulo, Rio Grande do Sul, and Bahia. RESULTS: Three thousand four hundred seventy individuals were included, of which 59.8% were male (n = 2,074) and 50.6% were current smokers (n = 1,758), with 60.7 years (standard deviation 8.8 years). Lung-RADS 4 was observed in 233 (6.7%) patients. Biopsy was indicated by minimally invasive methods in 122 patients (3.5%). Two patients who demonstrated false-negative biopsies and lung cancer were diagnosed in follow-up. Diagnosis of lung cancer was observed in 74 patients (prevalence rate of 2.1%), with 52 (70.3%) in stage I or II. Granulomatous disease was found in 20 patients. There were no statistical differences in the incidence of lung cancer, biopsies, granulomatous disease, and Lung-RADS 4 nodules between public and private patients. CONCLUSION: There are still many challenges and obstacles in the implementation of LCS in developing countries; however, our multi-institutional data were possible to obtain satisfactory results in these scenarios and to achieve similar results to the main international studies. Granulomatous diseases did not increase the number of lung biopsies. The authors hope that it could stimulate the creation of organized screening programs in regions still endemic for tuberculosis and other granulomatous diseases.

Evaluation of the extent of pulmonary cysts and their association with functional variables and serum markers in lymphangioleiomyomatosis (LAM).

PURPOSE: Although computed tomography (CT) has been used previously to assess disease severity in lymphangioleiomyomatosis (LAM), the associations between the extent of pulmonary cysts on CT and six-minute walk test (6MWT), matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF-D) are not well established. We performed a cross-sectional study to quantify the extent of pulmonary cysts in CT and to establish their correlations with pulmonary function tests (PFTs), 6MWT results, including a composite index (desaturation-distance ratio, DDR), and levels of VEGF-D and MMPs in LAM. METHODS: Twenty-three LAM patients underwent CT scanning to automatically quantify the extent of pulmonary cysts and performed PFTs and 6MWT. Serum levels of MMP-2, MMP-9, and VEGF-D were also measured. RESULTS: The severity of pulmonary cystic involvement was mild (the extent of cysts was 6.8 %) and correlated best with FEV1/FVC (r = -0.84), residual volume (r = 0.66), DLCO (r = -0.82), the DDR index (r = 0.77), and desaturation during the 6MWT (r = -0.81). There was a weak correlation with VEGF-D (r = 0.45), but no association was found with MMP-2 and MMP-9. CONCLUSIONS: The severity of pulmonary cystic involvement was mild in this sample of LAM patients and correlated best with airway obstruction, air trapping, reduced DLCO, the DDR index, and desaturation during the 6MWT. Serum VEGF-D cannot be completely defined as a valuable marker of disease severity and there may be a mechanism independent of MMPs to explain the formation of pulmonary cysts.