Measuring Risk Factors of Developing SCLC

Qian Wang, MD, MPH, assistant professor at Case Western Reserve University, thoracic oncologist at University Hospital Seidman Cancer Center, discusses the relevant metrics to determine the risk factor of developing small cell lung cancer (SCLC).

SCLC accounts for about 50% of all cases of lung cancer, with smoking being the leading cause of developing lung cancer. According to the CDC, nearly 9 out of 10 deaths due to lung cancer are caused by smoking cigarettes or exposure to second-hand smoke. Moreover, over 7,300 nonsmokers die each year from lung cancer that is caused by second-hand smoke. Over 85% of lung cancers are related to a history of smoking and in patients with SCLC it is rare for non-smokers to develop the disease. In comparison, about 25% of non–small cell lung cancer (NSCLC) cases are non-smoking related.

Wang discusses these outcomes and how physicians can determine a patient’s risk factor of SCLC based on their pack years and intensity of smoking over that period. She also highlights that patients with a lower intensity of smoking have shown a greater risk to develop lung cancer if they smoke longer than those with a higher intensity of smoking but lower amount of pack years.

Transcription:

0:08 | About 95% of [cases of] SCLC can be attributed to smoking, and this number is cited [as] lower for NSCLC. In NSCLC, we know [that] up to 25%, depends on which region [or] which population you're looking at, [but] 25% can be non-smoking related. I think another important thing to note is that we have several smoking metrics to assess the effect of smoking on lung cancer risks, including [in] SCLC.

0:46 | It’s very known to us is the pack year, which is packs per day, the intensity times duration, [and] how long [they] have smoked. But, studies have shown that those 2 factors actually contribute differently. So, for example, an equal total exposure or pack years, actually smoking at a lower intensity over a longer time period leads to a higher risk of lung cancer, including SCLC, compared to smoking at a higher intensity over a shorter time period. So, it means that the duration probably contributes to more lung cancer risks, then the intensity.