Non-smokers account for 20% of lung cancer diagnoses

Almost five new cases of lung cancer are diagnosed every minute globally and one of them would be a non-smoker. Screening gap remains one of the critical challenges of lung cancer prevention as most of the current screening programs are offered to smokers. Genetic testing provides an alternative screening option to identify genetic mutations before symptoms appear, saving a time window for timely treatment.

Doctor Diagnosed with Cancer

Dr. Bryant Lin, Clinical Professor of Medicine at Stanford University and co-founder of Stanford's Center for Asian Health Research and Education, experienced a profound shock not from a patient's diagnosis, but from his own.

Despite never having smoked, a six-week persistent cough led him to discover his own cancer. An X-ray revealed a shadow, a CT scan confirmed its severity, and a bronchoscopy delivered the devastating news: stage IV lung cancer, metastasized to liver, bones, and brain.

"It never strikes you that you're going to be the one with the disease," Dr. Lin reflected in an interview with the American Lung Association. Genetic testing later identified an EGFR exon 19 deletion, a common mutation particularly among Asian populations. "Many people don't realize that anyone can get lung cancer, regardless of smoking history."

Prevalence on the Rise

Lung cancer remains the most commonly diagnosed cancer and the leading cause of cancer death globally. In 2022 alone, approximately 1.8 million lives out of 2.5 million new cases, according to the World Health Organisation (WHO). A projection study, published last year, suggests reaching an estimated 4.62 million new cases and 3.55 million deaths annually by 2050.

Environmental factors like air pollution and secondhand smoke contribute, but genetics play an increasingly recognized role. Mutations in genes like EGFR, ALK, ROS1, and others can drive lung cancer development independently of tobacco exposure. Yet, current screening paradigms largely ignore this population.

Screening Gap Among Non-Smokers

Lung cancer in non-smokers often begins with vague symptoms that are easily mistaken for other chronic obstructive pulmonary disease (COPD). The disease is frequently at a late stage by the time advanced imaging is ordered, as in Dr. Lin's case. Diagnosed at an advanced stage will drastically lower survival chances.

The cornerstone of early lung cancer detection, Low-Dose CT (LDCT) screening, is predominantly targeted at current or former heavy smokers. The US Preventive Services Task Force (USPSTF) guidelines explicitly state that screening is not recommended for people who have never smoked. The potential harms of screening are believed to outweigh the potential benefits of finding rare cancer early, including false positives leading to unnecessary invasive procedures and radiation exposure.

Know Early, Treat Timely

Genetic testing offers a paradigm-shifting alternative. Unlike LDCT scans, which involve radiation and carry risks of false positives, genetic tests analyzing saliva or blood samples are non-invasive and pose virtually no physical harm. These tests can identify inherited or acquired genetic mutations associated with significantly increased lung cancer risk long before any symptoms appear.

Dr. Lin’s EGFR mutation is a prime example. Tests like the BGI Genomics SENTIS™ Hereditary Cancer Testing utilize advanced sequencing to assess an individual's genetic predisposition for up to 25 types of hereditary cancers, including lung cancer. By analyzing key genes like EGFR, these panels provide crucial insights.

These genetic insights help identify high-risk mutations, allowing individuals and their clinicians to understand their elevated susceptibility. A positive genetic finding can justify earlier and more frequent monitoring. Knowledge of genetic risk empowers individuals to discuss preventative strategies and be hyper-vigilant about symptoms.

Early Detection Saves Lives

Realizing the underfunding of lung cancer research after the government cut its support, Dr. Lin began raising awareness during his own treatment. He also launched a class on cancer care at Stanford, offering a uniquely informed perspective on the patient journey.

"We have great evidence now that lung cancer in smokers can be detected early, so we need policies that make sure these types of preventative medicine are covered," he urges.

The rising global burden of lung cancer demands a more nuanced approach. Relying solely on smoking history as the gatekeeper for life-saving screening is insufficient and leaves a vulnerable population exposed.

Genetic testing provides a safe tool to identify high-risk individuals before symptoms arise, enabling earlier intervention. Lung cancer screening must look beyond the smoke. Integrating genetic risk assessment into lung cancer prevention strategies is an important step towards equity and effectiveness in combating this deadly disease.

About BGI Genomics SENTIS™ Hereditary Cancer Testing

SENTIS™ Hereditary Cancer Testing uses target region capture combined with high-throughput sequencing technology to detect 90 germline genes and assess the risk of 25 types of cancer. It provides clinicians with one of the market’s most comprehensive and accurate solutions for the identification of clinically actionable mutations and the discovery of novel variants with important functions in cancer.

About BGI Genomics

BGI Genomics, headquartered in Shenzhen, China, is the world's leading integrated solutions provider of precision medicine. Our services cover more than 100 countries and regions, involving more than 2,300 medical institutions. In July 2017, as a subsidiary of BGI Group, BGI Genomics (300676.SZ) was officially listed on the Shenzhen Stock Exchange.