Doc: Ozone therapy pretty far-fetched treatment

Keith Roach
To Your Health

Dear Dr. Roach: We have a friend who’s currently undergoing ozone therapy for a bone-on-bone knee condition. He was told that the ozone therapy will “build up tissue,” apparently referring to the area between the knee bones. I have been led to believe that one cannot grow back replacement tissue between the bones. It sounds pretty far-fetched to me. What are your thoughts?


Dear H.J.: It sounded pretty far-fetched to me, too, but a 2015 study from Brazil showed that injecting ozone into the knees of people with osteoarthritis relieved pain and improved the ability to do daily activities. The study was presented at a prestigious conference, but has not been published yet. Ozone has not been compared with other standard treatments, and although the group that did the study is looking at MRI scans to see whether the cartilage improved, that part isn’t clear.

Ozone is not approved in the U.S. (or Brazil), and special care was taken in the study to avoid inhaling ozone, which is toxic. Two subjects in the study had “puncture accidents.”

Given the preliminary nature of the evidence, the lack of approval for the procedure, the potential for harm and the inability to compare with standard treatments, I can only say that ozone looks promising, but I can’t recommend it outside of a study situation. I have seen many instances where a treatment looks great in early trials, but fails completely when subjected to more rigorous analysis.

Dear Dr. Roach: I have cancer. A recent CT scan showed no evidence of cancer, but I will have a PET scan next month. What does a PET scan show that a CT scan doesn’t?


Dear R.D.: A positron emission tomogram uses a radioactive analog of sugar (18-FDG) to identify areas of intense metabolic activity. Most PET scans now are combined with a CT to add in this ability to see metabolic activity. Not all tumors take up 18-FDG, but PET/CT scanning often improves sensitivity to detecting new or residual cancer.

Dr. Roach Writes: Several patient advocates wrote to tell me that polycythemia vera is a cancer, not a myeloproliferative disorder, as I had said. However, polycythemia vera is not considered a cancer, although it can undergo malignant transformation to become a cancer, a leukemia. Leukemias and lymphomas are considered blood cancers.

The question of whether it is a cancer is less important than the fact that polycythemia is a neoplasia (“neo”’ for “new,” “plasia” for “growth”) that has a worse prognosis than some cancers, although generally a better prognosis than most leukemias and lymphomas.

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