For almost five years, 22-year-old Todd Blake has lived with an unusually persistent form of Hodgkin's lymphoma, which normally is curable. Blake's treatment has included chemotherapy and two bone marrow transplants, with much of it provided in the college student's hometown of Jacksonville, Florida. But other treatments have required trips to cities as far away as Seattle. Recently, after the discovery that his previous treatment regimen was no longer keeping his cancer in remission, Blake was offered the opportunity to participate in a clinical trial at the Center for Lymphoid Malignancies at Columbia University Medical Center in New York City. That offer came with a catch: Blake would have to fly to New York once a week, for at least eight weeks. If the treatment works, he still would need to keep flying to New York about once a month—"endlessly," he noted—and if it doesn't work, he would begin a different trial that would require once-per-week trips. "If I flew by myself every single time, it would probably be over $500 per trip when all is said and done," Blake said, noting the cost of a round-trip flight and ground transportation. That was a prohibitive sum of money for Blake, he said.

Todd Blake, a cancer patient undergoing treatment in New York, and his mother Nancy Source: Corporate Angels Network

But Columbia told Blake about a way to avoid those costs: the Corporate Angel Network, a charity that for 33 years has connected cancer patients who need to travel for their treatments with companies that have empty seats open on corporate jets they own. Patients like Blake can catch a ride for free on those jets whenever seats are available, and the planes are flying to and from the patients' homes and treatment center cities. As a result, patients routinely rub elbows on those planes with corporate executives, including company CEOs, who are headed to the same destination. Read MoreObamacare premiums being paid

On April 24, Blake became the 45,000th cancer patient to hitch a ride on a Corporate Angel Network-arranged flight when he flew from an airport in White Plains, New York, back home to Florida after getting treatment at Columbia. The jet belonged to investment giant BNY Mellon, which has offered unused seats via CAN since the late 1980s. The company is one of 592 that are in the charity's current roster of jet seat donors. Blake, who made the trip accompanied by his mother Nancy, said the nearly dozen Mellon employees who were on the flight "were all very nice...I had a really nice conversation with them." Since then, CAN has paid for flights on commercial jets that Blake has taken to and from New York each week.

Corporate Angel Network homepage Source: Corporate Angel Network

"I really wouldn't be able to continue with these trials endlessly without the aid of an organization like that," said Blake, who in addition to his studies runs a non-profit named the Live for Today Foundation, which helps young adult cancer patients. "I just think it's amazing that these companies sign up to do this," said Blake. "It really says a lot about them. They don't have to do it, they opt into it, and that's what's really charming." Read MoreEinhorn's Athenahealth short nothing new

In addition to BNY Mellon, CAN participating corporations include big names such as General Electric, Pepsico, American Express, Xerox, Verizon, Starbucks, Procter & Gamble and ConocoPhillips. "We average about one flight per month, or about a dozen a year to support the organization," said BNY Mellon spokesman Ron Gruendl, who added that the corporation "is honored" to participate in CAN's program. "Since our company leaders and board of directors approved our participation more than three decades ago, we've been able to witness first-hand that this service improves patients' chances of survival, as well as reduces their emotional stress, physical discomfort and financial burden," Gruendl said. CAN's new executive director, Dick Koenig, said the charity's roster of jet-owning companies include about half of the Fortune 100 and more than 20 percent of the Fortune 500. CAN's six-person staff and nearly 20 volunteers hook up patients needing air travel for treatment with available jets, which are tracked by location, destination, and seats available—information that is provided by the flight departments of corporations. "About 6,000 requests a year come in, and about 2,800 get fulfilled," said Koenig, whose charity is based at the Westchester County Airport in White Plains. CAN spreads the word about its services via pro-bono ad space in media, communications by major cancer treatment centers, and "we're all over the Internet as well," Koenig said. Read MorePfizer-AstraZeneca deal talk sparks protectionist jibes

"We don't care whether you're rich or poor, you just have to have cancer," said Koenig, who is the former publisher of Flying magazine. Many of the patients, such as Blake, are traveling with relatives that are helping them get to and from treatment, and their travel is also provided by CAN.

Dick Koenig, executive director, Corporate Angel Network Source: Corporate Angels Network