The most effective treatment for the most common type of lymphoma has been used by only a tiny fraction of patients who would benefit from it. Even worse, the treatment faces the possibility of being discontinued completely.

Sounds unbelievable, but it’s true. Few cancer patients even know about this lifesaving, but endangered, treatment, called radio-immunotherapy or RIT.

Two RIT drugs have been approved by the Food and Drug Administration for non-Hodgkin’s lymphoma: Bexxar and Zevalin. Study after study shows that both give longer remissions, are less toxic, and have fewer side effects than any other treatment for non-Hodgkin’s lymphoma, the fifth most common cancer in the United States.

But hardly anyone is using RIT.

Why? Because a little known but powerful federal agency called the Centers for Medicare and Medicaid Services (CMS) will not fully reimburse hospitals for prescribing RIT to their patients. The agency has never completely explained this decision, and private insurers have followed CMS’s lead in not paying for the therapy.

Hospitals that do prescribe RIT lose thousands of dollars with each treatment. So for the most part, they don’t even mention it as an option.

CMS, whose executives declined an interview request by Newsmax Health, will make a final ruling on how RIT gets reimbursed on Nov. 1.

Scott Seaman, an attorney and founder of the Chicago Blood Cancer Foundation, said: “Taxpayers funded the research for RIT, which was developed in part by the National Institutes of Health, and now taxpayers are being cheated out of the benefit of their investment.”

A nationwide grassroots movement led by patient advocate Betsy de Parry urging CMS to fully reimburse for these treatments generated more than 1,500 signatures on a petition in just a few weeks. But, said de Parry, “No one knows what CMS is going to do. We’re all watching, and waiting.”