Hypoxia is a critical hallmark of solid cancer tumors and involves enhanced cell survival, angiogenesis, glycolytic metabolism, and metastasis. Hyperbaric oxygen (HBO) treatment has for centuries been used to improve or cure disorders involving hypoxia and ischemia, by enhancing the amount of dissolved oxygen in the plasma and thereby increasing O2 delivery to the tissue. At a recent medical conference in Florida about cancer and metabolism, researchers showed that there are many new modalities to treat cancer using high levels of oxygen. It is believed that many cancer cells thrive in a hypoxic environment, so the thought is that giving the cells more oxygen may help to disable the cancer cell and kill it.
As oxygen is believed to be required for all the major processes of wound healing, one feared that the effects of HBO would be applicable to cancer tissue as well and promote cancer growth. Furthermore, one also feared that exposing patients who had been treated for cancer, to HBO, would lead to recurrence. Systematic reviews on HBO and cancer have concluded that the use of HBO in patients with malignancies is considered safe. There is no evidence indicating that HBO neither acts as a stimulator of tumor growth nor as an enhancer of recurrence. On the other hand, there is evidence that implies that HBO might have tumor-inhibitory effects in certain cancer subtypes. We need to expand our knowledge on the effect and the mechanisms behind tumor oxygenation.