Lung Cancer in Nonsmoking Individuals: A Review

Importance: Lung cancer in nonsmoking individuals (defined as people who have smoked fewer than 100 cigarettes in their lifetime) accounts for 15% to 20% of all lung cancer cases worldwide. In the US, the annual incidence of lung cancer in nonsmoking individuals is 14.4 to 20.8 per 100 000 person-years in females and 4.8 to 12.7 per 100 000 person-years in males.

Observations: Most lung cancers in nonsmoking individuals are histologically adenocarcinomas (60%-80%) with the remainder being squamous or adenosquamous (10%-20%) and rarely small cell lung cancer (<10%). Risk factors include exposure to passive smoking, radon exposure, air pollution, asbestos, and history of lung cancer in a first-degree family member. Therapeutically targetable genomic variants, such as EGFR mutations or ALK gene rearrangements, are more common in tumors from nonsmoking individuals compared with those with a smoking history (defined as people who currently or formerly smoked) (43% vs 11% for EGFR and 12% vs 2% for ALK). In contrast, tumor mutation burden, the number of somatic mutations in a tumor cell, is lower in lung cancer among nonsmoking individuals (0-3 mutations/megabase [Mb] vs 0-30 mutations/Mb). Similar to individuals with a history of smoking, nonsmoking individuals with lung cancer may present with wheeze, chest pain, dyspnea, hemoptysis, or symptoms attributable to metastatic disease (eg, bone pain and headache) or be diagnosed with incidentally detected disease. The US Preventive Services Task Force does not currently recommend lung cancer screening with low-dose computed tomographic scans for nonsmoking individuals, although screening guidelines vary globally. Treatment typically involves a combination of surgery, radiotherapy, and systemic therapies depending on stage, performance status, and molecular features of the tumor. Comprehensive next-generation sequencing should be performed on stage Ib to IIIa lung cancer tumor tissue from nonsmoking individuals because actionable genomic alterations, such as EGFR mutations or ALK gene rearrangements, are treated with targeted therapy such as the tyrosine kinase inhibitors osimertinib or lorlatinib, respectively. Median survival among nonsmoking individuals with advanced non-small cell lung cancer (stage IIIb or higher) and actionable genomic alterations can exceed 3 to 5 years, while survival without these genomic alterations is similar to lung cancer in people with a history of smoking (1-2 years).

Conclusions: Lung cancer in nonsmoking individuals accounts for 15% to 20% of lung cancer cases worldwide. Among patients with lung cancer, nonsmoking individuals are more likely to have genomic alterations such as EGFR mutations or ALK gene rearrangements, and these patients have improved survival when treated with tyrosine kinase inhibitors compared with chemotherapy.

Author/s:

Cian Murphy, Tej Pandya, Charles Swanton

Bronchoscopic Lung Volume Reduction: A New Hope for Patients With Severe Emphysema and Air Trapping

Brian Desmarais — Mon, 31 Aug 2020 21:38:45 +0000

Date Added:

August 31, 2020

Journal/Publication:

Mayo Clinic proceedings

Publication Date:

August 20, 2020

URL:

Bronchoscopic Lung Volume Reduction: A New Hope for Patients With Severe Emphysema and Air Trapping

Type:

Meta-analyses, Reviews, and Guidelines

Format:

Article

DOI (1):

doi: 10.1016/j.mayocp.2020.03.027

MeSH

Residual Volume

Pneumonectomy

Cost-Benefit Analysis

cause of death

Pulmonary Emphysema

pulmonary disease, chronic obstructive

Lung Volume Measurements

Lung

Dyspnea

Emphysema

referral and consultation

This relatively new procedure is probably worth knowing about. I’m not sure where, other than Mayo, it is being done. James W. Mold, MD, MPH

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Chronic obstructive pulmonary disease (COPD) is common and has significant morbidity and mortality as the fourth leading cause of death in the United States. In many patients, particularly those with emphysema, COPD is characterized by markedly increased residual volume contributing to exertional dyspnea. Current therapies have limited efficacy. Surgical resection of diseased areas of the lung to reduce residual volume was effective in identified subgroups but also had significant mortality in and suboptimal cost effectiveness. Lung-volume reduction, using bronchoscopic techniques, has shown substantial benefits in a broader patient population with less morbidity and mortality. This review is meant to spread the awareness about bronchoscopic lung-volume reduction and to promote its consideration and early referral for patients with advanced COPD and emphysema frequently encountered by both primary care physicians and specialists. A search was conducted on PubMed (MEDLINE), EMbase, and Cochrane library for original studies, using the following keywords: "lung-volume reduction." "endobronchial valves," "intrabronchial valves," "bronchoscopic lung-volume reduction," and "endoscopic lung-volume reduction." We included reports from systematic reviews, narrative reviews, clinical trials, and observational studies. Two reviewers evaluated potential references. A total of 27 references were included in our review. Included studies report experience in the diagnosis and bronchoscopic treatment for emphysema; case reports and non-English or non-Spanish studies were excluded.

Author/s:

Abia-Trujillo, David, Johnson, Margaret M, Patel, Neal M, Hazelett, Britney, Eric S Edell, Kern, Ryan