Computed tomography on lung cancer screening is useful for adjuvant comorbidity diagnosis in developing countries.

Purpose: The aim of this study was to analyse and quantify the prevalence of six comorbidities from lung cancer screening (LCS) on computed tomography (CT) scans of patients from developing countries. Methods: For this retrospective study, low-dose CT scans (n=775) were examined from patients who underwent LCS in a tertiary hospital between 2016 and 2020. An age- and sex-matched control group was obtained for comparison (n=370). Using the software, coronary artery calcification (CAC), the skeletal muscle area, interstitial lung abnormalities, emphysema, osteoporosis and hepatic steatosis were accessed. Clinical characteristics of each participant were identified. A t-test and Chi-squared test were used to examine differences between these values. Interclass correlation coefficients (ICCs) and interobserver agreement (assessed by calculating kappa coefficients) were calculated to assess the correlation of measures interpreted by two observers. p-values <0.05 were considered significant. Results: One or more comorbidities were identified in 86.6% of the patients and in 40% of the controls. The most prevalent comorbidity was osteoporosis, present in 44.2% of patients and in 24.8% of controls. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46% of cases, respectively. The kappa coefficient for CAC was 0.906 (p<0.001). ICCs for measures of liver, spleen and bone density were 0.88, 0.93 and 0.96, respectively (p<0.001). Conclusions: CT data acquired during LCS led to the identification of previously undiagnosed comorbidities. The LCS is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatment.

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.

Thoracic aortic size in Brazilian smokers: measures using low-dose chest computed tomography anatomical and epidemiological assessment.

OBJECTIVES: Thoracic aortic aneurysms (TAAs) represent one-third of the hospitalizations for aortic diseases. The prevalence rate depends on the definition of the normal size of the aorta, which is quite variable, depending on the population studied. The aim of this study was to evaluate the characteristics of the thoracic aorta of Brazilian smokers, identifying the normal size of the aorta, presence of anatomical variations, and prevalence of TAA. MATERIALS AND METHODS: A total of 711 patients underwent radiological evaluation with low-dose computed tomography (CT) from January 2013 to July 2014 with the initial objective of lung nodule tracking. Two examiners evaluated these images, and measurements of maximum and serial diameters were performed manually in true orthogonal planes. Serial diameter measurements were taken every 2 cm in the ascending aorta and 5 cm in the descending segment. We searched for anatomical variations, aortic arch type, and correlations between anatomical characteristics, sex, body mass index, and body surface area (BSA). RESULTS: The maximum diameters were 33.61 (standard deviation [SD] 3.88), 28.66 (SD 2.89), and 28.36 mm (SD 3.09) for the ascending segment, aortic arch, and descending segment, respectively. A positive correlation was found between male sex, age, and BSA and aorta diameter. The bovine arch was the most common variation of the aortic arch type, and we found one (0.14%) case of TAA. CONCLUSIONS: This study with low-dose CT allowed the determination of the mean diameters of the ascending aorta, aortic arch, and descending aorta in Brazilian smokers and TAA prevalence.

Thoracic aortic size in Brazilian smokers: measures using low-dose chest computed tomography anatomical and epidemiological assessment

OBJECTIVES: Thoracic aortic aneurysms (TAAs) represent one-third of the hospitalizations for aortic diseases. The prevalence rate depends on the definition of the normal size of the aorta, which is quite variable, depending on the population studied. The aim of this study was to evaluate the characteristics of the thoracic aorta of Brazilian smokers, identifying the normal size of the aorta, presence of anatomical variations, and prevalence of TAA. MATERIALS AND METHODS: A total of 711 patients underwent radiological evaluation with low-dose computed tomography (CT) from January 2013 to July 2014 with the initial objective of lung nodule tracking. Two examiners evaluated these images, and measurements of maximum and serial diameters were performed manually in true orthogonal planes. Serial diameter measurements were taken every 2 cm in the ascending aorta and 5 cm in the descending segment. We searched for anatomical variations, aortic arch type, and correlations between anatomical characteristics, sex, body mass index, and body surface area (BSA). RESULTS: The maximum diameters were 33.61 (standard deviation [SD] 3.88), 28.66 (SD 2.89), and 28.36 mm (SD 3.09) for the ascending segment, aortic arch, and descending segment, respectively. A positive correlation was found between male sex, age, and BSA and aorta diameter. The bovine arch was the most common variation of the aortic arch type, and we found one (0.14%) case of TAA. CONCLUSIONS: This study with low-dose CT allowed the determination of the mean diameters of the ascending aorta, aortic arch, and descending aorta in Brazilian smokers and TAA prevalence.

Lung Cancer Mortality and the Availability of Chest Computerized Tomography: A Longitudinal Nationwide Study.

Lung-cancer screening with chest computerized tomography (CT) is not easy to introduce in low-medium resource countries due to cost issues. We investigated whether the increasing availability of chest CT exams in Brazil, in spite of no lung-cancer screening protocol, was associated with lung-cancer death rate along 10-year follow-up. We performed regressions to estimate the rate ratio between chest CT exams and lung-cancer deaths per 105 inhabitants. We stratified data per municipality. Regressions were adjusted for physicians and hospital beds per 105 inhabitants and per capita gross domestic product. Increasing availability of chest CT exams predicted decreasing lung-cancer death rate.

Challenges in Lung Cancer Screening in Latin America.

Lung cancer is the deadliest cancer worldwide and is of particular concern for Latin America. Its rising incidence in this area of the world poses myriad challenges for the region's economies, which are already struggling with limited resources to meet the health care needs of low- and middle-income populations. In this environment, we are concerned that regional governments are relatively unaware of the pressing need to implement effective strategies for the near future. Low-dose chest computed tomography (LDCT) for screening, and routine use of minimally invasive techniques for diagnosis and staging remain uncommon. According to results of the National Lung Screening Trial, LDCT lung cancer screening provided a 20% relative reduction in mortality rates among at-risk individuals. Nevertheless, this issue is still a matter of debate, particularly in developing countries, and it is not fully embraced in developing countries. The aim of this article is to provide an overview of what the standard of care is for lung cancer computed tomography screening around the world and to aid understanding of the challenges and potential solutions that can help with the implementation of LDCT in Latin America.

Lung cancer: a brief review of epidemiology and screening.

The global burden of lung cancer has been increasing over the past years, and is still a major threat to public health worldwide, leading to disabilities and premature mortality. Despite multifactorial cause, smoking remains as the major etiological factor, followed by occupational exposure to carcinogens, genetic predisposition and other concomitant diseases. In order to reduce the individual and social burden due to the direct and indirect costs related to the lung cancer treatment, accurate methods of screening are needed. Among those, x-ray with cytological analysis of sputum was first proposed. Nowadays, more sensitive methods such as low-dose computed tomography are being used to improve the early detection. In the future, molecular biomarkers may complement low-dose computed tomography and improve the robustness of early lung cancer detection.

Computed Tomography-Guided Percutaneous Thoracic Duct Sclero-Embolization for Persistent Chylothorax.

Postoperative chylous leak is often a consequence of thoracic duct injury during surgical procedures. Persistent chylothorax can be an extremely morbid condition. The authors describe a case of a refractory and long-standing chylous leak after thoracotomy for mediastinal lymphangioma removal. The patient was treated with a computed tomography-guided percutaneous thoracic duct sclero-embolization after failure of the conventional therapies. The chest tube output abruptly decreased after the procedure and was removed at 13th day. Percutaneous thoracic duct sclero-embolization proved to be safe and effective in the treatment of a persistent chylothorax.

Do Current Lung Cancer Screening Guidelines Apply for Populations With High Prevalence of Granulomatous Disease? Results From the First Brazilian Lung Cancer Screening Trial (BRELT1).

BACKGROUND: Low-dose computed tomography (LDCT) screening for lung cancer has been demonstrated to be effective in reducing cancer mortality. However, these studies have not been undertaken in countries where the incidence of granulomatous disease is high. The First Brazilian Lung Cancer Screening Trial (BRELT1) has completed initial accrual and is now in the follow-up phase. We present results from the initial prevalence round of screening. METHODS: The inclusion criteria were the same as those for the National Lung Cancer Screening Trial (NLST). Pulmonary nodules larger than 4 mm were considered positive and required evaluation by a multidisciplinary team. Indeterminate nodules were evaluated with fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) or biopsy when indicated. Statistical analysis was performed with Fisher's exact test to compare our positive findings with those of the NLST. RESULTS: From January 2013 to July 2014, 790 participants were enrolled. Positive LDCT scans were reported in 312 (39.4%) participants, with a total of 552 nodules larger than 4 mm. The comparison between positive findings in the NLST (7,191 of 26,722 cases) and those in the BRELT1 (312 of 790 cases) showed a significant difference (p < 0.001). The positive predictive value was lower in BRELT1 than in the NLST (3.2% versus 3.8%, respectively). Follow-up imaging was indicated in 278 of 312 (89.1%) participants; 35 procedures were performed in 25 participants. In 15 cases, benign lesions were diagnosed. Non-small-cell lung cancer (NSCLC) was diagnosed in 10 patients (prevalence of 1.3%). In 8 patients (stage IA/IB disease), treatment was by resection only, in 1 patient neoadjuvant chemotherapy was used (stage IIIA), and in 1 patient advanced disease was diagnosed (stage IV). CONCLUSIONS: Using NSLT criteria, a larger number of patients had positive scans (nodules), compared with previous lung cancer screening studies. However, the number of participants requiring surgical biopsy procedures and who were ultimately identified as having cancer was similar to other reports. This supports the role of screening in patient populations with a high incidence of granulomatous inflammation.

Semiquantitative analysis of surgical biopsies of distinct lung lobes of patients with usual interstitial pneumonia/idiopathic pulmonary fibrosis.

OBJECTIVE: To evaluate the differences between surgical biopsies of distinct lung lobes in terms of the histopathological features of usual interstitial pneumonia, using a semiquantitative score. METHODS: We selected all of the patients diagnosed with idiopathic pulmonary fibrosis and submitted to surgical biopsy in two distinct lobes between 1995 and 2005 at the Hospital São Paulo and other hospitals operated by the Federal University of São Paulo. In the histological evaluation of the specimens, we used a semiquantitative method based on previous studies, assigning a score to each of the biopsied sites. RESULTS: In this sample of patients, we found no statistically significant differences that would alter the stage of the disease, based on the score used. This finding was independent of the biopsy site (middle lobe or lingular segment). CONCLUSIONS: No significant histological differences were found between the lung lobes studied. The definitive histological diagnosis of usual interstitial pneumonia did not alter the stage of the disease.