Can Lung Cancer Be Caught Early?
Lung cancer is the leading cause of cancer deaths in both men and women in the United States. While early detection is our best defense against most cancers, lung cancer detection can be difficult. By the time symptoms appear, the disease is usually in an advanced, non-curable stage.
Efforts to decrease deaths from lung cancer have centered mainly on prevention, most notably with public health warnings about the danger of cigarette smoking. At the same time, the medical community has been searching for an effective, low-risk screening method, similar to mammography, as a way to detect lung cancer in its earliest stages, before symptoms begin to occur.
The breakthrough came in 2011 when results from a National Lung Screening Trial (NLST), a three-year clinical trial involving more than 50,000 people, were published in the New England Journal of Medicine. The test used both annual low dose CT scans and chest X-rays to detect abnormal areas in the lungs that might be lung cancer. People in the study had to be current or former smokers in fairly good health.
The results were positive. People getting the low dose scans over the three-year period had a 20% lower chance of dying from lung cancer than those in the study who had received annual chest rays. One death from lung cancer was prevented per 320 persons screened.
This landmark study clearly showed the effectiveness of annual screenings in a high-risk population. Several professional groups and associations all advocated the careful use of annual screenings with low dose CT scans for patients at high risk for lung cancer. Most insurance companies including Medicare followed these recommendations by covering the screenings for high-risk patients.
The American Cancer Society (ACS) provided guidelines for the establishment of community-based lung cancer screening programs, modeled on the NLST study.
Criteria for potential patients include:
- 55 to 80 years old
- In fairly good health, for example, able to have further tests or surgery if cancer is found
- Have at least a 30 year, one pack-day smoking history, or a 15 year, two-packs-a-day smoking history
- Are either still smoking or have quit within the last 15 years
ACS also recommended screening done only at facilities with low dose CT scanning equipment, a team experienced in this type of imaging and specialists available if further tests and follow up care are needed.
Marin County is an especially healthy community, with only 6% of adults who smoke, compared to 14% of adults in California. Lung cancer nonetheless was the leading cause of cancer-related deaths in Marin County between 2010 and 2012.
With overwhelming support from Marin County physicians who are involved in lung cancer diagnoses and treatments, Marin General Hospital is initiating a program offering lung cancer screenings as the standard of care for people considered to be at high risk for lung cancer.
Primary care physicians, using the patient’s medical condition and smoking history, will identify patients at risk for lung cancer and recommend screening. After discussing the pros and cons with the patient, and if the patient is willing, the physician will make a referral to the program. Patients who believe they are candidates for a screening can begin the conversation with their physicians and both then can make the decision about whether to proceed.
At the time of the procedure, the patient will have an ultra-low dose CT scan which will then be read by a radiologist. Using special software, a score will be assigned to the scan to determine if the patient needs immediate further evaluation or possibly a shorter term follow-up exam. A tumor board will look at and discuss each abnormal scan to see if any additional information can be gleaned in addition to the radiologist’s report.
If the scan is read as normal, the patient and the referring physician will get a letter stating as such and that a follow-up scan may be scheduled in a year if appropriate.
While early detection is your best defense against lung cancer, as a physician who cares for lung cancer patients, I cannot help but add screenings are not a substitute for quitting smoking. To lower your lung cancer risk, talk to your doctor about ways to quit smoking. For more information about the lung cancer screening program, call 1-415-925-7010 ext. 50672.