Screening for lung cancer

Recommendations for the implementation of a national lung cancer screening program in Portugal-A consensus statement

Lung cancer (LC) is a leading cause of cancer-related mortality worldwide. Lung Cancer Screening (LCS) programs that use low-dose computed tomography (LDCT) have been shown to reduce LC mortality by up to 25 % and are considered cost-effective. The European Health Union has encouraged its Member States to explore the feasibility of LCS implementation in their respective countries. The task force conducted a comprehensive literature review and engaged in extensive discussions to provide recommendations. These recommendations encompass the essential components required to initiate pilot LCS programs following the guidelines established by the World Health Organization. They were tailored to align with the specific context of the Portuguese healthcare system. The document addresses critical aspects, including the eligible population, methods for issuing invitations, radiological prerequisites, procedures for reporting results, referral processes, diagnostic strategies, program implementation, and ongoing monitoring. Furthermore, the task force emphasized that pairing LCS with evidence-based smoking cessation should be the standard of care for a high-quality screening program. This document also identifies areas for further research. These recommendations aim to guarantee that the implementation of a Portuguese LCS program ensures high-quality standards, consistency, and uniformity across centres.

The assessment of the role of baseline low-dose CT scan in patients at high risk of lung cancer

BACKGROUND

Despite the progress in contemporary medicine comprising diagnostic and therapeutic methods, lung cancer is still one of the biggest health concerns in many countries of the world. The main purpose of the study was to evaluate the detection rate of pulmonary nodules and lung cancer in the initial, helical low-dose CT of the chest as well as the analysis of the relationship between the size and the histopathological character of the detected nodules.

MATERIAL/METHODS

We retrospectively evaluated 1999 initial, consecutive results of the CT examinations performed within the framework of early lung cancer detection program initiated in Szczecin. The project enrolled persons of both sexes, aged 55-65 years, with at least 20 pack-years of cigarette smoking or current smokers. The analysis included assessment of the number of positive results and the evaluation of the detected nodules in relationship to their size. All of the nodules were classified into I of VI groups and subsequently compared with histopathological type of the neoplastic and nonneoplastic pulmonary lesions.

RESULTS

Pulmonary nodules were detected in 921 (46%) subjects. What is more, malignant lesions as well as lung cancer were significantly, more frequently discovered in the group of asymptomatic nodules of the largest dimension exceeding 15 mm.

CONCLUSIONS

The initial, low-dose helical CT of the lungs performed in high risk individuals enables detection of appreciable number of indeterminate pulmonary nodules. In most of the asymptomatic patients with histopathologically proven pulmonary nodules greater than 15 mm, the mentioned lesions are malignant, what warrants further, intensified diagnostics.

Survival of patients with or without symptoms undergoing potentially curative resections for primary lung cancer

BACKGROUND

Numerous historical screening programs to detect lung cancer have been undertaken. With technologic advances, complimentary diagnostic tests have been developed; however, only the National Lung Cancer Trial has demonstrated increased survival. Following the success of this study, screening programs are being trialled in several countries. Screening should, in theory, reduce lung cancer deaths by identifying asymptomatic patients with earlier tumors. This study asked whether lung cancer patients who are asymptomatic at presentation have a better survival than those who present with symptoms.

METHODS

This was a retrospective analysis of a validated prospective thoracic surgery database from a tertiary center in the Northwest of England. Included were 1,546 consecutive patients (826 men, 720 women) who received operative intervention for non-small cell lung cancer. The main outcome measures included 5-year survival and univariate and multivariate Cox regression analysis.

RESULTS

Cancer stage, age, and operation type were confirmed as being of prognostic importance, validating previous studies. Survival between asymptomatic or symptomatic patients did not differ significantly (p = 0.489), regardless of stage. The hazard ratios (with 95% confidence intervals) for variables associated with poorer outcome identified by Cox's regression analysis were male sex, 1.34 (1.15 to 1.56); advancing age, 1.03 (1.02 to 1.04); advancing stage, 3.30 (2.69 to 4.04); and pneumonectomy, 1.24 (1.01 to 1.52). Symptoms were not a significant variable affecting survival on multivariate analysis.

CONCLUSIONS

This retrospective study from the Northwest of England showed that in our subset of lung cancer patients undergoing resection, asymptomatic patients with non-small cell lung cancer do not have improved survival, implying it is a systemic disease in many at diagnosis. Care should be taken when generalizing the results of the National Lung Screening Trial to all populations until further validation has been performed.

Urinary volatile compounds as biomarkers for lung cancer: a proof of principle study using odor signatures in mouse models of lung cancer

A potential strategy for diagnosing lung cancer, the leading cause of cancer-related death, is to identify metabolic signatures (biomarkers) of the disease. Although data supports the hypothesis that volatile compounds can be detected in the breath of lung cancer patients by the sense of smell or through bioanalytical techniques, analysis of breath samples is cumbersome and technically challenging, thus limiting its applicability. The hypothesis explored here is that variations in small molecular weight volatile organic compounds (“odorants”) in urine could be used as biomarkers for lung cancer. To demonstrate the presence and chemical structures of volatile biomarkers, we studied mouse olfactory-guided behavior and metabolomics of volatile constituents of urine. Sensor mice could be trained to discriminate between odors of mice with and without experimental tumors demonstrating that volatile odorants are sufficient to identify tumor-bearing mice. Consistent with this result, chemical analyses of urinary volatiles demonstrated that the amounts of several compounds were dramatically different between tumor and control mice. Using principal component analysis and supervised machine-learning, we accurately discriminated between tumor and control groups, a result that was cross validated with novel test groups. Although there were shared differences between experimental and control animals in the two tumor models, we also found chemical differences between these models, demonstrating tumor-based specificity. The success of these studies provides a novel proof-of-principle demonstration of lung tumor diagnosis through urinary volatile odorants. This work should provide an impetus for similar searches for volatile diagnostic biomarkers in the urine of human lung cancer patients.

Clinical factors related to suspected second primary lung cancer development in patients with head and neck cancer

PURPOSE

The rate of second primary lung cancer development for patients with head and neck cancer (HNC) has been noted. The aim of our study was to evaluate the incidence and clinical features of suspected second primary lung cancer that developed in patients with primary HNC.

MATERIALS AND METHODS

We conducted a retrospective study of 469 patients who were newly diagnosed with HNC at the Korea University Medical Center between January 2000 and December 2006.

RESULTS

A total of 469 patients were included (389 men and 80 women). Eighteen patients (3.8%) had suspected second primary lung cancers. Statistically significant clinical variables for lung cancer development included the origin site for the primary HNC (oro-hypopharynx and larynx) (p=0.048), abnormal chest x-ray findings (p=0.027) and the histological HNC type (squamous cell carcinoma) (p=0.032). When the second primary lung cancers were combined with HNCs, the adjusted overall survival of patients with a second primary lung cancer was 16 months (p<0.001).

CONCLUSIONS

Considering the relative risk factors for a second primary lung cancer developing in patients with HNC, advanced diagnostic tools, such as chest CT or PET CT scan, should be applied for the early detection of a second primary lung cancer.

The aryl hydrocarbon receptor attenuates tobacco smoke-induced cyclooxygenase-2 and prostaglandin production in lung fibroblasts through regulation of the NF-kappaB family member RelB

Diseases such as chronic obstructive pulmonary disease and lung cancer caused by cigarette smoke affect millions of people worldwide. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that influences responses to certain environmental pollutants such as tobacco smoke. However, the physiological function(s) of the AhR is unknown. Herein we propose that the physiologic role of the AhR is to limit inflammation. We show that lung fibroblasts from AhR(-/-) mice produce a heightened inflammatory response to cigarette smoke, typified by increased levels of cyclooxygenase-2 (COX-2) and prostaglandins (PGs), when compared with wild type (AhR(+/+)) fibroblasts. This response was dependent on AhR expression as transient transfection of an AhR expression plasmid into AhR(-/-) fibroblasts significantly attenuated the smoke-induced COX-2 and PG production, confirming the anti-inflammatory role of the AhR. The AhR can interact with NF-kappaB. However, the heightened inflammatory response observed in AhR(-/-) fibroblasts was not the result of NF-kappaB (p50/p65) activation. Instead it was coupled with a loss of the NF-kappaB family member RelB in AhR(-/-) fibroblasts. Taken together, these studies provide compelling evidence that AhR expression limits proinflammatory COX-2 and PG production by maintaining RelB expression. The association between RelB and AhR may represent a new therapeutic and more selective target with which to combat inflammation-associated diseases.