“Twenty percent of lung cancer cases in the United States are diagnosed in people who never smoked.
“This translates to between16,000 and 24,000 Americans annually, according to the American Cancer Society. The majority of these cases are non–small cell lung cancer.
“Although the exact cause for increased proportion of lung cancer cases among never-smokers has not been established, researchers suggest environmental factors may to be blame.
“However, they emphasize more data are needed to identify the factors that are driving the increase ― and determine the most appropriate treatment options for never-smokers ― before changing practice.”
“Lung cancers account for more than one-quarter of cancer deaths in the United States, and the disease is expected to kill nearly 160,000 Americans in 2016 alone. Early detection, which occurs in just 15% of cases, remains the best avenue to longterm survival; about half of patients found to have an early-stage lung cancer are alive 5 years after diagnosis, compared with fewer than 5% of patients whose cancers are detected after metastasis.
“The National Lung Screening Trial studied more than 53,000 patients and demonstrated that low-dose helical computed tomography (CT) is more effective at lung cancer early detection than standard chest X-rays, yielding—over an observation period of about 7 years—a 20% lower risk of dying from the disease. The trial enrolled only symptomless current or former smokers ages 55 to 74 who had a smoking history of 30 packyears (that is, a pack a day for 30 years, or 2 packs a day for 15 years) and who had been smokers within the prior 15 years.”
In March 2011, Janet Freeman-Daily was about to take a long family trip to China. She’d been coughing for a while, so she asked her doctor for an antibiotic as a precaution before leaving. Even so, she came back in May with a respiratory infection that wouldn’t go away.
Her doctor ordered an X-ray and then a CT scan. “Before I got home, they called and said they’d like to do a bronchoscopy,” Janet says. The scan revealed a 7-cm mass in her left lung, and biopsies showed it was non-small cell lung cancer (NSCLC) and that it had spread to several lymph nodes. Continue reading…
“The incidence of non–small cell lung cancer has more than doubled among individuals who have never smoked, according to research presented at the World Conference on Lung Cancer.
“The incidence of never-smokers diagnosed with NSCLC increased from 13% in 2007 to almost 28% in 2013, according to researchers. Further, many of these never-smokers presented with advanced-stage disease.
“Eric Lim, MD, MSc, a thoracic surgeon at Royal Brompton Harefield NHS Foundation Trust in London, and colleagues sought to define the incidence of NSCLC in never-smokers. In addition, researchers used data from the prospectively collected database of patients at Royal Brompton to evaluate clinical features of never-smokers who presented early with NSCLC and underwent surgery.
“The analysis included data from 2,170 patients who underwent lung cancer surgery between March 2008 and Nov. 2014.”
“In a meta-analysis reported in the Journal of Clinical Oncology, Lee et al found that increased progression-free survival benefit of EGFR tyrosine kinase inhibitor treatment vs chemotherapy was exhibited in patients with exon 19 deletion, never-smokers, and women.
“The meta-analysis included seven trials (N = 1,649) comparing EGFR tyrosine kinase inhibitors with chemotherapy in patients with newly diagnosed advanced EGFR-mutant disease. Overall, tyrosine kinase inhibitor therapy was associated with significantly prolonged progression-free survival (hazard ratio [HR] = 0.37, 95% confidence interval [CI] = 0.32–0.42)…
“The investigators concluded: ‘Although EGFR [tyrosine kinase inhibitors] significantly prolonged [progression-free survival] overall and in all subgroups, compared with chemotherapy, greater benefits were observed in those with exon 19 deletions, never-smokers, and women. These findings should enhance drug development and economic analyses, as well as the design and interpretation of clinical trials.’ “
International Association for the Study of Lung Cancer | June 24, 2013
Few studies so far have focused specifically on lung cancer in women, despite increasing evidence of differences in lung cancer features between women and men. A striking example is the higher rate among women of nonsmokers who develop lung cancer. A recent study of women with lung adenocarcinoma, a type of non-squamous non-small cell lung cancer (NSCLC), found that those who had never smoked were much more likely to have mutations in the EGFR gene and/or abnormally high levels of estrogen receptors, while smokers were more likely to have mutations in the KRAS gene. Based on these findings, a new phase II clinical trial will explore the effectiveness of treating postmenopausal, nonsmoking women who have advanced non-squamous lung cancer with EGFR inhibitors and anti-estrogen drugs.