COPD-associated expiratory central airway collapse (ECAC) is a frequently overlooked benign airway obstructive disease with complex causes and unclear pathologic and physiologic mechanisms. Although interventions such as noninvasive positive pressure ventilation, airway stenting, and tracheobronchoplasty have shown definite efficacy in the treatment of COPD-associated ECAC, the diagnosis and treatment of this disease remain challenging. This review provides a systematic evaluation and outlook on the epidemiologic features, causes, pathophysiologic characteristics, clinical manifestations, diagnosis, and treatment of COPD-associated ECAC.

Impaired pulmonary function carries significant risks for lung, cardiovascular, and metabolic disorders.

Lymphangioleiomyomatosis (LAM) is a rare cystic lung disease affecting women and is characterized by the proliferation of abnormal smooth muscle-like cells within the lungs, kidneys, and lymphatic system. FEV1 and diffusing capacity of the lungs for carbon monoxide (Dlco) are 2 commonly used markers for evaluating the status of LAM, although the disease may be associated predominantly with changes in only 1 of these parameters. In this special feature, we trace the historical evolution of Dlco and FEV1 in LAM up to their current uses, beginning with their relationship in early studies with histopathologic features and imaging. We transition to the use of Dlco and FEV1 in the context of sirolimus therapy and monitoring rates of change in lung function. Finally, we examine modern imaging methods and how these techniques have contributed to our understanding of LAM progression, with a focus on the unique and perhaps undervalued role of Dlco. The LAM histologic score, which measures the involvement of cysts and LAM cells in the lung via biopsy, relates to disease stages and aligns more with Dlco than FEV1. The cyst score, calculated from high-resolution CT scans, is a measure of the lung parenchyma occupied by cysts and correlates with disease progression. Large cysts as visualized by high-resolution CT imaging predominantly influence FEV1, whereas smaller cysts, which impact a greater surface area of the lung and may be underestimated, tend to affect Dlco.

The advances in minimally invasive lung cancer diagnostics of the last decade have transformed patient care but have also raised important concerns about the regulatory processes used to approve new devices and the best way to generate data to support their use. Disruptive technologies, such as robotic bronchoscopy, have been widely adopted by interventional pulmonologists in the absence of robust data demonstrating improved patient outcomes. Comparative research is needed to inform patient care, but traditional methods of conducting clinical trials in which research teams operate separately from clinical teams are ill-suited to testing the safety and effectiveness of technologies being introduced on the market at unprecedented speed. Pragmatic clinical trials, which integrate trial procedures into routine clinical care, represent an appealing alternative approach for generating much-needed data to inform clinical care. In this article we illustrate the advantages and disadvantages of these research paradigms, using two recently completed randomized controlled trials in navigational bronchoscopy, and highlight the barriers and facilitators to using pragmatic trials to address the gap in comparative effectiveness research: these include the need for increased clarity of research regulations for pragmatic trials, adequate federal and private funding for such research, and alignment of incentives between clinicians, researchers, regulators, and industry.

Trastuzumab emtansine has been recently suspected to be associated with the development of pulmonary arterial hypertension (PAH).

The incidence of pulmonary nodules and masses in immunocompromised patients without HIV has significantly increased due to advancements in hematopoietic stem cell transplantation and solid organ transplantation and the widespread use of chemotherapy and immunosuppressive therapies. Differentiating between infectious and noninfectious causes is critical for appropriate diagnosis and management, especially because radiologic and clinical presentations can be nonspecific.

We previously identified a sputum 12-gene methylation panel that predicts lung aging and risk for lung cancer.

The independent, mediation, interaction, and joint effects of socioeconomic status (SES) and phenotypic frailty on the incidence of COPD are unclear.

OSA causes episodes of fragmented sleep and intermittent hypoxia and leads to excessive daytime sleepiness (EDS). Deficits in cognitive function are a troublesome symptom in patients with OSA and EDS.

Quantitative CT imaging may be a useful predictor of outcome in rheumatoid arthritis-related interstitial lung disease (RA-ILD).

Current guidelines do not recommend β-blockers in pulmonary arterial hypertension (PAH) unless indicated by comorbidities. However, the evidence regarding the role of β-blockers in PAH is contradictory.

There are limited US Food and Drug Administration-approved medications and real-world data on sarcoidosis treatment in the United States. Concordance of practice patterns with guideline recommendations have not been well characterized.

Response to pulmonary rehabilitation is not equal for all participants and may vary across health outcomes for any one individual. Alternative methods of pulmonary rehabilitation delivery, for example, telerehabilitation, may improve program access, but also could affect response to rehabilitation.