Review of Effectiveness of High Dose Ozone Therapy on Oncology Patients

Background

Ozone has been investigated as a complementary therapy in oncology for two related reasons. It generates reactive oxygen species, and tumour tissue is often poorly oxygenated compared with healthy tissue. Cancer cells typically carry weaker antioxidant defences than healthy cells, which has led researchers to ask whether controlled oxidative stress might affect them selectively, and whether improving oxygen levels in a tumour might make conventional treatments such as radiotherapy work better. This paper gathers that reasoning, together with supporting laboratory and clinical work, in one place.

Study design

This is a review by Andres Felipe Rodriguez Molina and David Aurelio Contreras Galindo, published in the Journal of Cancer Therapy and Research. The authors describe their approach as a systematic review, stating that they searched databases including PubMed, ScienceDirect and Google Scholar using terms such as "ozone therapy AND cancer", and that studies were appraised using the GRADE method under PRISMA guidance. However, the paper does not include a PRISMA flow diagram, does not state a search date range, and does not report explicit inclusion or exclusion criteria or the number of studies screened versus included. In practice it reads more like a narrative review than a fully documented systematic review, and it does not report new patient outcomes of its own or present a pooled statistical analysis.

Findings

The review sets out several proposed mechanisms. Reactive oxygen species are described as selectively targeting cancer cells with lower antioxidant defences, prompting apoptosis (programmed cell death). Better tumour oxygenation is proposed as a route to improving the effectiveness of radiotherapy. Ozone is also described as modulating immune responses through the activation of immune cells.

Alongside those mechanisms, the review reports on studies in which ozone reduced side effects of chemotherapy and radiotherapy, with associated improvements in patients' quality of life.

What the authors concluded

The authors describe the results as promising but unsettled. They call for standardised dosing protocols and large-scale, multi-centre randomised trials before high-dose ozone therapy could be regarded as established practice in cancer care.

Limitations of this study

The most significant limitation is the kind of paper this is. A review summarises other researchers' work and cannot demonstrate efficacy on its own. Although the authors describe their method as systematic and reference PRISMA and GRADE, the paper does not include the documentation - a search date range, defined inclusion and exclusion criteria, a PRISMA flow diagram, or a stated number of screened and included studies - that would normally support that label. Without those details, there is no way to judge how completely the underlying evidence has been covered, or whether studies with negative or null results were captured.

The absence of standardised dosing, which the authors themselves flag, means results are not directly comparable between studies. It is also worth separating two different claims: reduced treatment side effects and improved quality of life are reported more consistently than any effect on the cancer itself, and those are not the same thing. The journal itself is a smaller specialist title and does not appear to be indexed in PubMed or Scopus, which is worth bearing in mind when weighing the strength of this evidence.

This study concerns a narrative-style review of proposed mechanisms and reported secondary effects, such as reduced treatment side effects, of high-dose ozone therapy in oncology patients, not new clinical trial data. It does not establish ozone as a treatment or cure for cancer itself. Ozone therapy is a complementary approach and should always be discussed with your oncology team.