Terry Fox Research Institute-led study develops new clinical tool that accurately classifies, nine out of ten times, benign and malignant spots on lung CT scans of smokers
VANCOUVER, Sept. 4, 2013 /CNW/ – A Terry Fox Research
Institute(TFRI)-led study has developed a new clinical risk calculator
software that accurately classifies, nine out of ten times, which spots
or lesions (nodules) are benign and malignant on an initial lung
computed tomography (CT) scan among individuals at high risk for lung
The findings are expected to have immediate clinical impact worldwide
among health professionals who currently diagnose and treat individuals
at risk for or who are diagnosed with lung cancer, and provide new
evidence for developing and improving lung-cancer screening programs. A
total of 12,029 lung cancer nodules observed on CTs of 2,961 current
and former smokers were examined in the population-based study.
The results, to be published in the Sept. 5(th) issue of the New England Journal of Medicine (NEJM), will have an immediate impact on clinical practice, says
co-principal investigator Dr. Stephen Lam, chair of BC’s Provincial
Lung Tumour Group at the BC Cancer Agency and a professor of medicine
at the University of British Columbia.
“We already know that CT screening saves lives. Now, we have evidence
that our model and risk calculator can accurately predict which
abnormalities that show up on a first CT require further follow up,
such as a repeat CT scan, a biopsy, or surgery, and which ones do not.
This is extremely good news for everyone – from the people who are high
risk for developing lung cancer to the radiologists, respirologists and
thoracic surgeons who detect and treat it. Currently, there are no
Canadian guidelines for us to use in clinical practice.”
In countries where guidelines do exist, they largely relate to nodule
size. The pan-Canadian team’s prediction model, developed by Brock
University epidemiologist Dr. Martin Tammemägi, includes a risk
calculator that considers several factors in addition to size: older
age, female sex, family history of lung cancer, emphysema, location of
the nodule in the upper lobe, part-solid nodule type, lower nodule
count and spiculation (presence of sharp or needle-like points).
“Reducing the number of needless tests and increasing rapid, intensive
diagnostic workups in individuals with high-risk nodules are major
goals of the model,” says Dr. Tammemägi.
The TFRI team used two sets of data to determine their findings,
studying a total of 12,029 nodules from 2,961 persons - current and
former smokers, aged 50-75, who had undergone low-dose CT screening.
One set involved participants in the TFRI Pan-Canadian Early Detection
of Lung Cancer Study from 2008 to 2010, where 1,871 persons with a
total of 7,008 nodules (102 of which were malignant) were screened and
followed. The other set involved 1,090 persons with 5,021 nodules (of
which 42 were malignant) who took part in several lung cancer
prevention trials conducted by the BC Cancer Agency during 2000-2010
and were funded through the U.S. National Cancer Institute (NCI). In
the former study, participants were followed for an average of three
years; in the latter, for an average of eight-and-a-half years.
Dr. Lam says the prediction model holds up even in cases where
clinicians are faced with the toughest challenges; for example,
deciding what to do when nodules are the approximate size of a
blueberry or smaller. While nodule size is one predictor of lung
cancer, the largest nodule appearing on the CT was not necessarily
cancerous. The pan-Canadian study team found that nodules located in
the upper lobes of the lung carry an increased probability of cancer.
In both data sets studied, researchers found that where cancer was
present, fewer nodules were found. This model will simplify the work
involved, especially for radiologists, in evaluating and assessing
nodules on scans, as well as respirologists and thoracic surgeons who
must make decisions about tests and treatment for their patients.
“An accurate and practical model that can predict the probability that a
lung nodule is malignant and that can be used to guide clinical
decision making will reduce costs and the risk of morbidity and
mortality in screening programs,” wrote Dr. Lam and study colleagues in
the article, titled: Probability of Cancer in Pulmonary Nodules Detected on First Screening
“The findings in this study bolster the potential for the successful
implementation of a lung cancer screening program using low-dose
computed tomography (CT) within a high-risk population. This tool,
combined with CT-screening, will increase our success in earlier
detection, diagnosis and treatment of the disease. Further, this model
combined with new guidelines for best clinical practice, will provide
our health care system with both effective and affordable tools to
implement such a program,” says Nova Scotia thoracic surgeon Dr.
Michael Johnston, a member of the study team. Dr. Johnston serves on
the executive of the Terry Fox Research Institute and is chair of the
medical advisory committee of Lung Cancer Canada.
“Many jurisdictions throughout the world are now considering whether or
how to best implement lung cancer screening. Studies like this one are
key to answering important questions so decisions are most likely to
result in good practice and planning, and ultimately benefit patients,”
says Dr. Heather Bryant, vice-president, cancer control at the Canadian
Partnership Against Cancer.
The significant findings come on the heels of the U.S. National Lung
Screening Trial (2011) that found a 20% reduction in lung cancer
mortality with the use of low-dose thoracic computed tomography.
Dr. Christine Berg, co-principal investigator of the National Lung
Screening Trial and former chief, Early Detection Research Group,
division of cancer prevention, for the National Cancer Institute in the
United States, says: “This important work of Dr. Lam and colleagues is
a major advance for clinicians performing lung cancer screening. They
provide a tool to grapple with the problem of the high rate of positive
low-dose computed tomography scans. Fewer follow-up scans with their
attendant cost and fewer biopsies with their complications will need to
be performed while continuing to diagnosis lung cancer at an early
stage to lower mortality. Coupled with continued public health efforts
to lower cigarette smoking, this work will have international impact on
the leading cause of cancer death worldwide.”
The Pan-Canadian study is funded by the TFRI, the research arm of the
Terry Fox Foundation, and the Canadian Partnership Against Cancer. The
BCCA study was supported by the United States Public Health Service
National Cancer Institute. In Canada, lung cancer kills over 20,000
Canadians annually. It is the primary cause of cancer deaths in Canada.
One in 12 Canadians will receive a lung cancer diagnosis in his or her
lifetime. With early detection, five-year survival rates can be over
About TFRI/TFF: Launched in October 2007, The Terry Fox Research Institute (TFRI) is
the brainchild of The Terry Fox Foundation (TFF). TFRI seeks to
improve significantly the outcomes of cancer research for the patient
through a highly collaborative, team-oriented, milestone-based approach
to research that will enable discoveries to translate quickly into
practical solutions for cancer patients worldwide. TFRI collaborates
with over 50 cancer hospitals and research organizations across Canada.
The Terry Fox Foundation (TFF) maintains the vision and principles of
Terry Fox while raising money for cancer research through the annual
Terry Fox Run, National School Run Day and other fundraising
initiatives which, to date, have raised over $600 million worldwide.
The 33rd Terry Fox Run will take place across Canada at more than 800
community sites on Sunday, September 15. People are invited to run,
walk, wheel, or ride up to 10km to raise funds to support cancer
B-roll on You Tube (related video) : http://www.youtube.com/watch?v=KI5jPXG-N40
Dr. Lam is available for media interviews
Other experts available for comment:
Dr. Martin C. Tammemägi, Brock University
Dr. Heather Bryant, Canadian Partnership Against Cancer
Dr. Christine Berg, Co-Principal Investigator, US National Lung
Related photos and video available at www.tfri.ca
SOURCE Terry Fox Research Institute