Cangen Biotechnologies Inc., a small start-up in Bethesda, has a big goal: Develop a highly reliable test that detects lung cancer long before it is identified on a CT scan, giving patients a better chance at surviving.

The company has been testing mass spectrometry technology that vaporizes blood so the content can be analyzed for proteins indicating the presence of early-stage lung cancer. While the technology seems good at identifying people who are positive for cancer, there are still false readings.

Enter Olympus Corp., the global imaging company known primarily for its snazzy digital cameras but also a maker of endoscopes and other medical examination devices. It is developing a high-speed microchip that can identify variations in DNA samples that signal lung cancer, bypassing complicated, time-consuming and expensive laboratory equipment.

Cangen recently announced that it is partnering with Olympus, hoping to combine the two technologies to create a test with better than 90 percent accuracy that doctors can use in routine exams.

The partnership between a fledging biotech firm and a global imaging company illustrates an increasingly popular tactic in the life sciences industry. While many high-profile biotech firms are working on drugs to treat lethal diseases, others are racing to develop diagnostic tests that spot disorders long before they develop.

"We are really trying to predict the presence of lung cancer, which probably sounds a little weird because non-scientists think of cancer as either being there or not being there," said Richard A. Silfen, Cangen's president and chief financial officer. "But in fact, what we want to do is predict whether it is there."

Olympus isn't the only big name in imaging technology moving into the biotech business. Canon U.S. Life Sciences Inc., a division of the global manufacturer of digital cameras, copiers, and scanners, is moving from Virginia to Maryland this month as it continues examining diagnostic applications for its technology.

It's a natural extension. Companies like Olympus and Canon are expert at making complicated devices that can translate incoming data into useful information, just as a digital camera creates an image out of a stream of light.

In this case, biological samples are analyzed for molecular and genetic variations that occur before what is now commonly considered the onset of disease. The chip Olympus is developing, it is hoped, will make Cangen's existing diagnostic tools faster, cheaper and more accurate, according to the company.

Particularly in lung cancer, earlier diagnosis significantly increases the chance a patient will survive more than five years.

General Electric Co., already a leading producer of CT, MRI and other diagnostic scanners often used to detect the presence of tumors, is also trying to advance its diagnostics. Scientists there are developing "smart molecules" to seek out cellular changes in organs that occur before a disease actually attacks, according to company literature. The abnormal cells would then be visible on a computerized image in groups smaller than can be seen using current technology.

"We'll be able to say, 'Here is a very small bundle of cancer cells. These have to go,' " said William R. Clarke, chief medical and technology officer for GE Healthcare.

"It doesn't surprise me that these big companies are getting into this," said Scott Gottlieb, an analyst at American Enterprise Institute specializing in health policy. "The technology has been percolating to a level that we can achieve things that we have talked about for the last decade, especially in terms of catching disease before it happens."

But Gottlieb, also a former senior technology official at the Food and Drug Administration, said adoption of such technology may be a ways off. "Someone has to approve it. Someone has to pay for it. And then you have to teach doctors how to use it," he said.

Silfen's company has an uphill climb: It has just 16 employees and has raised about $20 million. But with Olympus's technology, Silfen likes his chances. "This would be like a lab on a chip," he said. "They are minimizing and mechanizing a lot of complicated processes that would normally be conducted in a lab."

Canon executives have not disclosed exactly what kind of tests or instruments the company will pursue. Debra Epstein, a company spokeswoman, said the venture in Rockville will start small, with a handful of employees occupying 7,500 square feet at 9800 Medical Center Dr. Biotech observers have big expectations for the venture, largely because it is being headed by Rita R. Colwell, former director of the National Science Foundation and former president of the University of Maryland Biotechnology Institute.

County and state officials lobbied Canon for months to persuade them to operate in Montgomery County, hoping it will add a dimension beyond drug development to the county's biotech industry.

"You want to have drug development and delivery systems and diagnostics," said David Edgerly, the county's economic development director. "That's what makes a whole industry."

Ashley Lynch, a Cangen research associate, holds a vial of blood serum next to a graph comparing a chromatogram of normal serum with cancerous serum.