This time, the media is being very positive. News reports about the new treatment for chronic lymphocytic leukemia are ripe with palpable excitement. If I have any caution at all it is over the fact that the results are preliminary, based on a study at the University of Pennsylvania of only three patients.

But the study showed dramatic results. Two of the patients with advanced CLL were cleared of cancer, and the third showed a 70% response. There was a lot of tumor destroyed with few side effects, though there is a concern about immune function.

The treatment was described in the prestigious New England Journal of Medicine as well as Science Translational Medicine. Here’s how it works: A gene is introduced into T cells by way of a virus, to reprogram them to attack cancerous B cells that are causing the leukemia. Perhaps most exciting, a blood test taken a year later showed these “terminator” cells were still around, and they had reproduced, providing continued protection against the cancer.

My word of caution is because of the small sample size. We have to see this tried over a long period of time in a large group of patients before we can be satisfied that it is well tolerated and effective.

But in the meantime, we may have a revolutionary new treatment on our hands, one well worth celebrating. Targeted therapies for cancer have moved us out of the dark ages of chemotherapy. Now we may have reached yet another revolution in cancer treatment—where we inject a patient with cancer police cells that stand guard against the cancer criminal coming back. 

Marc Siegel MD is medical director of Doctor Radio at NYU Langone Medical Center. He is author of The Inner Pulse; Unlocking the Secret Code of Sickness and Health