Researchers are exploring a way to peek inside the body of a patient undergoing chemotherapy to see if the treatment is working. Two small but provocative studies looked at the ability of a specialized PET scan to show what a tumor is doing. (PET is an acronym for positron emission tomography, a three dimensional scan common in most hospitals. Patients are injected with a radioactive substance, and the scan “lights up” in active areas. Standard PET scans look for blood sugar consumption.)
A new radioactive substance called fluorothymidine is even more precise: it shows whether cancer cells are dividing. According to Malcolm Ritter, an Associated Press science writer, two studies of patients in Korea and in Wisconsin enabled doctors to see whether tumors were responding to chemotherapy as soon as a day after treatment started.
As Ritter writes:
The hope is that, over time, FLT PET would prove reliable for giving a faster answer on whether an experimental treatment is working. That would save [drug] companies a lot of money, because they could spot ineffective drugs more quickly and not wast further research on them. And the drug company research would produce data to help persuade federal regulators to approve FLT PET for use in tracking therapy.
Lymphoma patients, in particular, are used to getting scans to assess whether their treatments are working. This new technology could provide faster answers for people getting chemo for other kinds of tumors. But it may take time, and larger studies, to change policy so that this “early look” is paid for under Medicaid and Medicare.