When federal regulators permitted the sale of an unproved device that uses intense heat to combat cancer, they did so for a compelling reason, to give hope to some women desperately ill with cervical cancer.
Over the next two years, however, the few hospitals that purchased the $500,000 device did not take part in a study of patients that the manufacturer agreed to perform as a part of the machine’s approval. Cancer experts also said they were surprised that the Food and Drug Administration had approved the machine in the first place.
The reason: The group of woman for whom the F.D.A. approved the treatment — those with advanced cervical cancer who are too ill for chemotherapy — is so small. “I see, like, one patient like this a year,” said Dr. Junzo P. Chino, a cancer expert at Duke University.
A look at the F.D.A.’s decision to approve the device, which is called the BSD-2000, opens a window onto a little-known regulation known as the humanitarian device exemption.
The program, even its critics agree, is based on the best intentions. Because companies have little incentive to run costly trials for products used by small groups of patients, the exemption requires a producer only to show that a device is safe and has a “probable” benefit, rather than prove its effectiveness, the usual standard.
The rule, which is similar to one governing drugs for extremely rare diseases, also does not require the F.D.A., companies or...