Lymphoma

After treatment, it is important to know if any active cancer cells remain in the body. In the past, the amount and type of therapy that was used were set according to standard rules. PET allows the type and amount of therapy to be directed specifically to you, the patient, and based on the location and extent of your type of cancer.

Imaging with PET is a critical test in order to look for the return of the cancer. Before PET, it was extremely difficult to monitor patients to see if the lymphoma had returned. Multiple CT scans would have to be done to capture images of the whole body and it still could not see the recurrent cancer as sensitively as PET. Delay in finding recurrence could result in a delay of further surgical removal.

PET can be used to image lymphoma tumor response to therapy and to detect recurrence in successfully treated lesions. Post treatment, PET plays an extremely important role in monitoring to see if the cancer cells have returned. Early studies have shown that PET may also identify patients who are more likely to achieve remission and less likely to relapse by showing a characteristic pattern of reduction in glucose uptake in the abnormal lymph nodes during chemotherapy.

If the cancer cells have been killed by the treatment, they will not absorb any of the radioactive glucose given in the PET scan. After treatment, although the tumor masses may still be present and seen on CT scans, the cells may no longer be alive, which can be shown by PET. Conversely, if the cancer cells have come back, PET can see the accumulation of the radioactive glucose much sooner than a CT scan. Treatment can be re-started sooner, improving the possibility of a better outcome.

Call the doctors at the PET centers nearest you if you have lymphoma and would like to discuss whether PET could be useful in your care.