Page 16

RADIOLOGY

L

ung cancer is the leading cause of cancer death for both men and women, not only in the United States, but worldwide. The American Cancer Society estimates that 224,390 new diagnoses of lung cancer will be made in 2016 in the U.S. This includes approximately 117,920 new diagnoses in men and about 106,470 in women. They estimate that 158,080 persons will die of lung cancer this year. Lung cancer accounts for 27 percent of all cancer-​related deaths. Smoking is by far the leading risk factor for lung cancer as approximately 80 percent of lung cancer deaths are thought to result from smoking. Over the last four decades there has been minimal improvement in the lung cancer mortality reduction from clinical interventions (Siegel, Naishadham, & Jemal, 2013). Often at the time of diagnosis, lung cancer is already at an advanced stage, with a five-year survival rate of approximately 17.4 percent

16

Lung cancer screening Understanding the fundamentals By Aaron Binstock, MD

(Surveillance Epidemiology and End Results Stat Fact Sheets: Lung and Bronchus Cancer, 2015). In light of the well-known risk factors for lung cancer, and the better prognosis with increased survival when caught and treated early, screening high-risk individuals for lung cancer has been studied in the past on multiple occasions without a clearly-defined benefit. This was largely due to limitations in CT technology for radiation dose reduction at that time and the low sensitivity and specificity of the chest X-ray (CXR) as a screening tool.

MINNESOTA PHYSICIAN JUNE 2016

The history of screening According to the American Cancer Society, lung cancer along with colon, breast, and prostate are the four leading causes of cancer death for both men and women in the U.S. and worldwide. Of these, lung cancer is the only one not subject to routine screening. Several studies have assessed ways to screen the at-risk population for lung cancer using various methods including CXR, sputum analysis, and lowdose computed tomography (LDCT). Prior studies using CXR and sputum analysis at varying intervals of time were not successful in reducing lung cancer-​ specific mortality (National Lung Screening Trial research [NLST]; and American College of Radiology [ACR] Lung Imaging Reporting and Data System). This is largely because a CXR typically does not detect early cancer (stage 1 and 2). The majority of lung cancer detected with CXR is stage 3 and 4, which have dismal prognoses. With the advancement of imaging technology, LDCT has become more promising. The National Lung Screening Trial, a study of over 53,000 patients, found a reduction in lung cancer mortality in highrisk patients aged 55 to 74 after being screened with LDCT compared with CXR. These individuals were enrolled and randomly assigned to three annual screens with either LDCT or CXR. The persons enrolled were considered high risk if they had a 30 pack-year history of cigarette smoking. Former smokers could also be enrolled, but they had to have quit in the past 15 years. The results showed a reduction of mortality of 20 percent in patients screened

with LDCT (ACR Lung Imaging Reporting and Data System). Since the release of the NLST results in 2011, at least 38 key stakeholder major medical societies and organizations have endorsed LDCT for the early detection of lung cancer. The U.S. Preventive Services Task Force (USPSTF) is an independent panel of non-​Federal experts in preventive and evidence-based medicine. They have endorsed LDCT and recommend annual LDCT screening for people 55 to 80 years of age who have a >30 pack-year smoking history, and currently smoke, or have quit within the past 15 years. As a result of these recommendations, most people considered to be at high risk who have insurance coverage, including Medicare, will be covered for screening with no copay.

Lung cancer accounts for 27 percent of all cancer-related deaths. A screening program A successful lung cancer screening program requires a coordinated approach with multispecialty provider involvement. A provider order is recommended for the screening LDCT. After performing a risk assessment and confirming that the patient is a candidate for lung cancer screening based on the listed criteria, the most important component of a screening program begins with patient education. Shared decision making The shared decision-making process should provide clear information to the patient of the risks and benefits of the screening process in a language appropriate to the candidate. The elements to be discussed during this visit with a health care provider should include the benefits and risks of screening, diagnostic testing, over-​ diagnosis, the false-positive rate, and total radiation exposure. With any screening test, there is a risk of a false positive or false negative exam. This can

MN Physician June 2016  

Volume XXX, No.3 2016 Health Care Architecture Honor Roll | Targeted temperature management: Improving outcomes in neurocritical care By...

MN Physician June 2016  

Volume XXX, No.3 2016 Health Care Architecture Honor Roll | Targeted temperature management: Improving outcomes in neurocritical care By...

Advertisement