Dr. Vincent Rajkumar has little incentive to care about the skyrocketing cost of cancer drugs. Prescribing them like a drunken sailor won't change his Mayo Clinic salary. Warning patients about sticker prices won't change their demand for drugs that offer hope of survival.

But after seeing cancer drug costs escalate 10- to 20-fold in the last 15 years, the hematologist decided enough is enough.

Calling it a "moral obligation," Rajkumar and a Houston colleague wrote an article in Mayo Clinic Proceedings challenging the rising costs and calling out drug companies for practices that extend patents and inflate profits.

People don't have to buy gold Apple watches if they can't afford them, but free market principles of choice don't apply for patients "willing to do anything to control their cancer," he said. "None of the companies have any pressure to price their drugs lower because they know the patients will have to take their drug anyway. Even if you use the first three drugs, you still need the fourth drug. So each drug is, in a sense, a monopoly."

Insurers capitulate when it comes to cancer drug costs, and factor increases into higher premiums, he argued. Federal regulators have OK'd medications with limited benefits and value.

Farydak was approved by the U.S. Food and Drug Administration in February despite a negative advisory committee opinion and data showing it only slows the progression of multiple myeloma about four months and can cause diarrhea and nerve pain in the process.

It costs $10,000 a month, the same as drugs with better track records, Rajkumar said. "There's no relationship in the pricing based on value."

Oddly, this is a problem of improving medical research. Larger studies can now statistically prove slight drug benefits, giving regulators the green light to approve them as long as they are considered safe.

Rajkumar suggested U.S. reforms, including granting the FDA or Medicare the authority to set target prices for new drugs on the market.

"In a monopoly," he said, "even the price of water will be sky high."