A quest to detect lung cancer — before it’s too late
MD ANDERSON STAFF
Early in his career, Sam Hanash, M.D., Ph.D., faced the difficult task of telling the families and loved ones of late-stage cancer patients that they had only a short time to live. Because cancers such as lung grow quietly and aren’t detected until they’ve become advanced and spread to other parts of the body, doctors don’t detect the disease until it’s too late.
Hanash, a professor of Clinical Cancer Prevention, resolved to find a way to detect cancer in its earliest stage, when the disease is still curable. His first target? Lung cancer, the No. 1 cause of cancer deaths because of its absence of early-stage symptoms.
Today, he’s leading a study that, when completed, is hoped to result in a simple, noninvasive blood test that can detect early-stage lung cancer. The test will hunt for tumor markers — microscopic telltale proteins or other molecules produced by the body in response to cancer.
“This test, when it’s available, will be practice-changing,” Hanash says.
The project is part of MD Anderson’s Moon Shots Program, a bold plan to quickly improve survival rates for many of the deadliest cancers, including lung cancer.
This past June, the institutions and Madison, Wisconsin-based Exact Sciences Corp. announced a partnership to co-develop and commercialize several blood-based screening and diagnostic tests for lung cancer.
“Lung cancer is, and will continue to be, America’s leading cancer killer unless we identify new approaches to diagnose it early, at its most treatable stages,” said Hanash.
Hanash spoke to Cancer Frontline about his team’s research, the importance of detecting lung cancer earlier and MD Anderson’s partnership with Exact Sciences.
Tell us about the need for improved lung cancer detection.
Currently the accepted means to screen for lung cancer in this country is through low-dose CT scan. This modality is associated with a high rate of false positives. CT scans have limited ability to determine whether nodules or lesions in the lungs are malignant or benign, resulting in invasive work-up. In fact, some 96 percent of all nodules detected by CT are benign. Therefore, there’s a need to improve lung cancer detection by reducing false positives. If a blood test could be developed that, if positive, determined the need for a CT scan, that would improve screening considerably.
If we had the ability to detect the disease earlier, what would that mean for patients?
It would mean increased survival and reduced mortality associated with the world’s No. 1 cause of cancer deaths. A 10 percent reduced mortality associated with lung cancer would have as much impact as complete cure for less common cancers.
Explain the approach MD Anderson is using to try and develop a better assay?
We are focusing on the development of a blood test that consists of several markers — or beacons — that light up at the earliest stages of lung cancer. A positive blood test would trigger the need to look for lung cancer by means of CT.
We have partnered with biotech company Exact Sciences to do this work. Why is the role they play so crucial?
Most diagnostic companies implement diagnostics based on assaying a single marker. We know that such strategies with single markers is not going yield a robust test for detecting lung cancer. Exact Sciences developed a multiplex panel of markers to screen for colon cancer for which they received approval from the Food and Drug Administration (FDA). This makes them an ideal partner to develop the multi-marker test to detect lung cancer.
What would be the desired outcome of this research?
Stated simply, it would be FDA approval of a blood test that could be using to screen for lung cancer among individuals at risk — notably smokers and ex-smokers.
How could our lung cancer research help combat other cancers?
The approach we’re developing for lung cancer is equally applicable to other common and deadly cancers such as pancreatic, liver and breast cancer. There is substantial concern at present about the utility of mammography for breast cancer screening and overdiagnosis. A blood test to complement mammography would alleviate some of the current issues with breast cancer screening. We have data that show promise for detecting breast cancer before the onset of symptoms.