A new generation of drugs that target cancer cells, while sparing the rest of the body, are being hailed by some doctors and patients as a breakthrough, but the prospect of a pill that can be taken at home, with few side effects , comes at a price that may be too high for some.

The new generation of “immunotherapy” drugs now in development or the process of being approved can cost as much as $100,000 for a year’s supply.

Canadian hockey legend Paul Henderson, who scored the game winning goal for Canada in the 1972 Summit Series against Russia, was diagnosed three years ago with chronic lymphocytic leukemia -- an often fatal cancer of the blood and bone marrow. With tumours present throughout his body, and few treatment options at his disposal, Henderson was able to join a U.S. study that provided the drug Imbruvica for free.

"I was down 20 pounds," he told CTV’s Canada AM. "I had no energy; everybody knew I was in deep trouble including myself."

Since his trial with Imbruvica began, Henderson has seen a remarkable turnaround.

"When I started, 80 per cent of my bone marrow was malignant, now it's down to five to 10 per cent," he said.

"He looks great, his tumours have melted away and his blood is almost normal," added his physician Dr. Ronan Foley.

While Health Canada has approved the use of Imbruvica, which patients could have to take for the rest of their lives, provinces have yet to decide whether they will foot the annual $100,000 per patient bill.

And this has cancer patients like Peter Dorfman, whose leukemia is in remission, worried that he won't have access to the best care available.

"Right now, at a $100,000 a year, it doesn't seem accessible," he told CTV Toronto. "We can sell the house. These are horrible choices people (might be) obliged to make because of the costs."

The senior national director for the Leukemia and Lymphoma Society, Lorna Warwick, echoed these concerns.

"How do we get our patients to have access to the best treatments out there, when the drugs may cost more than our system can pay?" she said.

Canadian cancer specialists meet next week to discuss whether to recommend Imbruvica for provincial coverage.

With a report from CTV's Medical Specialist Avis Favaro