Researchers Trying to Predict Lung Cancer Risk
CancerWise - November 2007
A new assessment tool may put medical science one step closer to identifying which smokers and nonsmokers are at higher risk of developing lung cancer, the deadliest of all cancers, experts say.
Significance of results
The prediction instrument, published by M. D. Anderson researchers in the Journal of the National Cancer Institute, is the first to use a scoring system to estimate a person's risk for the disease.
It also is the first to use data easily gathered by health care professionals.
The data include:
- Smoking history
- Secondhand smoke exposure in nonsmokers
- Family history of cancer, especially smoking-related
- Exposure to asbestos
- Hay fever history
Although smoking is the primary cause of close to 85% of lung cancers, fewer than 20% of lifetime heavy smokers develop lung cancer.
"If we know which smokers are at greatest risk for lung cancer, we can administer the most intensive smoking cessation interventions or perhaps even offer chemo-preventive interventions," says Margaret Spitz, M.D., professor and chair of
M. D. Anderson's Department of Epidemiology and the study's lead author.
"More importantly, we could intensively screen this population with modalities that might not be appropriate for the average at-risk population."
Using the model, clinicians can compute a patient's risk score and absolute chance of developing lung cancer. The patient then can be classified as high, moderate or low-risk.
The risk assessment tool was developed and tested based on research comparing the medical histories of:
- 1,851 lung cancer patients treated at M. D. Anderson
- 2,001 healthy individuals
Current, former and never smokers were studied separately. This is the first lung cancer assessment tool to include people who have never smoked.
The model's accuracy in predicting lung cancer is about 60%. The researchers say this is on par with similar tools for other diseases.
Family cancer history and emphysema were strong risk factors in current and former smokers. In contrast, a history of hay fever was a protective agent against lung cancer in both groups.
Lung cancer is the leading cancer killer in both men and women.
For 2007, the American Cancer Society predicts:
- 213,380 new cases
- 160,390 deaths from the disease
The study looked only at Caucasians because there were not enough minority patients in the test group to build and validate the model. The authors also plan to incorporate genetic markers into the models.
"We are working with other institutions to combine our numbers and build models specifically for Mexican-Americans and African-Americans," says Carol Etzel, Ph.D., an assistant professor in M. D. Anderson's Department of Epidemiology and the study's senior author.
"In preliminary testing, we are finding that while some of the risk factors are common to both groups, there are different levels of risk. The model for Caucasians will probably not be as predictive for other populations."
The researchers are developing a Web-based version of the assessment model for use by health care professionals.
– From staff reports