Healthe-Matters Logo

Essential health information from local experts

Lung Cancer Screening ~ Ask An Expert

Lung Cancer Screening ~ Ask An Expert

With Sarasota Memorial Radiologist Heitor Okanobo, MD

Welcome to “Ask an Expert,” a Q&A series with Sarasota Memorial’s team of doctors, nurses and other health experts, where you can get thorough answers to your health and wellness queries from a local source you can trust. Have a question that you’d like to “Ask an Expert”? Email it to

The number one cancer killer in the U.S., lung cancer often has no symptoms until it has spread. With screening, it can be detected at early stages, before symptoms present and when it is most treatable. According to the Lung Cancer Alliance, only 16% of the millions who are eligible for screening will be diagnosed at an early stage. We know lung cancer screening is a game changer—and we need more lung cancer success stories—so we reached out to Sarasota Memorial Cancer Institute Radiologist Heitor Okanobo, MD, to learn more about the latest lung cancer screening technology.

Q: What is Low Dose Computed Tomography (LDCT) screening?

Screening examinations are tests performed to find disease before symptoms begin. In lung cancer screening, individuals who have a high risk of developing lung cancer, but no signs or symptoms of the disease, undergo low-dose computed tomography (LDCT) scanning of the chest. 

Q: How does LDCT compare to chest X-rays for lung cancer screening?

The short answer is that LDCT is much better than chest X-rays for detecting lung cancer, especially at the early stages. 

The National Lung Screening Trial (NLST) — a lung cancer screening study sponsored by the National Cancer Institute and conducted by the American College of Radiology Imaging Network and the Lung Screening Study group — compared low-dose computed tomography and standard chest X-ray for detecting lung cancer, to examine their effects on lung cancer death rates in a high-risk population. Over a 21-month period, the trial followed 53,454 current or former heavy smokers, ages 55 to 74, through screening. Of those, 26,722 had LD CT and 26,732 had chest radiography at 33 screening centers across the U.S. After 21 months, the analysis of the study demonstrated that the patients who had the LDCT had a higher detection of cancer. As a consequence, that group had 20 percent fewer deaths than the group who had chest X-ray.

Q: Who is a good candidate for LDCT screening for lung cancer?

Anyone who is 55 to 80 years of age, who has a 30-pack-year or more history of smoking, and is either a current smoker or a former smoker who has quit within the last 15 years. 

“Pack-year” is a calculation determined by multiplying the number of cigarette packs (20 cigarettes per pack) smoked per day by the number of years the individual was a smoker. For example, if someone smoked one pack per day for 10 years, that would amount to a 10-pack year, or smoking one pack per day for five years would be a 5-pack-year.

Q: Why is LDCT screening not recommended for younger smokers?

Most people diagnosed with lung cancer are age 65 or older, while a very small number of people are diagnosed younger than 45. The average age at the time of diagnosis is about 70. As lung cancer is more prevalent in older ages, younger patients are not electable for LDCT screening.

Q: What are the benefits of LDCT?

The biggest benefit of LDCT is detecting lung cancer early, when the chances of being cured are higher. Lung cancer screening with LDCT has been proven to reduce the number of deaths from lung cancer in patients at high risk. 

Other benefits include:

  • The LDCT procedure is fast. The entire screening takes about 10 minutes, while the LDCT scan itself takes only a few seconds, which is important for patients who have trouble holding their breath.
  • LDCT scanning is painless and noninvasive; no contrast material is required.
  • No radiation remains in a patient's body after an LDCT examination.
  • X-rays used in LDCT of the chest have no immediate side effects and do not affect any metal parts in the body, such as pacemakers or artificial joints.
  • Low-dose CT scans of the chest produce high-quality images that enable detection of many abnormalities, using up to 90 percent less ionizing radiation than a conventional chest CT scan.
  • Medicare and most insurance plans cover individuals eligible for screening.

Q: What are the risks of LDCT?

  • False positive results (when a test appears to be abnormal but no lung cancer is found) sometimes occur. Abnormal findings may require additional testing to determine whether or not cancer is present. These tests, such as additional CT exams or more invasive tests in which a piece of lung tissue is removed (called a lung biopsy) have risks and may cause a patient anxiety.
  • Screening that detects lung cancer may not improve your health or help you live longer if the disease has already spread beyond the lungs to other areas of the body.
  • Any cancer screening exam could result in the detection and treatment of a cancer that may never have harmed you. This can result in unnecessary treatment, complications, and cost.

Q: If a smoker is referred for LDCT screening or decides on their own that they’d like to have it, what should they do?

They should ask their physician about a lung cancer screening program

Your physician will refer you to a program that has the right type of CT machine and that has experience in low-dose CT scans for lung cancer screening. The facility should also have a team of specialists (pulmonologist, radiologist, oncologist, pathologist, thoracic surgeons, and trained technologists and nurses) who can provide the appropriate care, analysis and follow-up of patients with abnormal LDCT results.

Enroll in a lung screening program is a good choice, if you are 55 to 80 years old, have a history of heavy smoking (an average of one pack a day for 30 years), and still smoke or quit within the last 15 years.

Q: Can you describe the process of coming in for LDCT screening?

After registering for the screening, you will be scheduled to have the test done.

During your appointment, you will put on a hospital gown, and a technologist will position you on the CT exam table, usually lying flat on your back. Straps and pillows may be used to help you maintain the correct position and to help you remain still during the scan. You also will be asked to raise your arms over your head. 

The table will move quickly through the scanner to determine the correct starting position for the scans. Then, the table will move slowly through the machine as the actual CT scanning is performed, while you hold your breath for the short five- to 10-second scan.

The images will be sent to a database, where a specialized radiologist will interpret the images and look for abnormalities. At the end of the analysis, the radiologist will categorize the screening using a method called “LUNG-RADS,” which will determine the next step.

Q: SMH’s Lung Cancer Screening program is accredited by the American College of Radiology and is a Go2 Foundation Screening Center of Excellence. Why is this important for patients?

The Go2 Foundation for Lung Cancer’s Screening Centers of Excellence (SCOE) are committed to responsible, high-quality screening practices. The SCOE designation means Sarasota Memorial Hospital excels in quality and earned a special certification. 

Designated Screening Centers of Excellence must comply with comprehensive, standards-based best practices developed by professional bodies such as the American College of Radiology (ACR), the National Comprehensive Cancer Network (NCCN) and the International Early Lung Cancer Action Program (I-ELCAP) for controlling screening quality, radiation dose and diagnostic procedures within an experienced, multi-disciplinary clinical setting. 

To earn the SCOE designation, facilities must:

  • Provide clear information on the risks and benefits of LDCT screening through a shared decision-making process.
  • Comply with standards-based best practices for controlling screening quality, radiation dose and diagnostic procedures.
  • Work with a lung cancer multidisciplinary clinical team to carry out a coordinated process for screening, follow up and treatment, when appropriate.
  • Include a comprehensive smoking-cessation program for those still smoking or refer patients to comprehensive cessation programs.
  • Report results to those screened and their primary care doctors and transmit requested copies in a timely manner.
  • Have received or intend to receive designation as a lung cancer screening program through the American College of Radiology.


Dr. Heitor Okanobo, a radiologist with Sarasota Memorial and Radiology Associates of Florida, completed medical school at State University of Campinas School of Medicine in Brazil and completed a residency and fellowship at Boston-based Brigham and Women’s Hospital, a teaching affiliate of Harvard Medical School. Dr. Okanobo specializes in Emergency, Thoracic and Musculoskeletal Radiology, along with Diagnostic Imaging.

Posted: Oct 30, 2018,
Comments: 0,
Author: Ann Key