The website of the US government shows that hyperbaric oxygen therapy (HBOT) has been proven effective in treating various types of cancer.
Clinical trial of hyperbaric oxygen therapy for breast cancer:
Hypoxia plays a major role in cell survival, angiogenesis, glycolytic metabolism and metastasis in breast cancer. Hyperbaric oxygen therapy (HBOT) has a well-established effect for attenuating the effects of hypoxia by enhancing the effects of chemotherapy drugs and increasing oxygen delivery to the tissues. The hypoxic environment encourages cancer cells to acquire stemness and become resistant to chemotherapeutic drugs. We have used HBOT as an adjunct to neoadjuvant chemotherapy in breast cancer patients with the objective of reducing tumour hypoxia and improving the response to chemotherapy. A randomised controlled trial was conducted in patients with breast cancer. The patients were randomly allocated into the study group receiving neoadjuvant chemotherapy (NAC) with HBOT and the control group who received NAC only. The NAC consisted of 3 cycles of intravenous injection of cyclophosphamide, 5-fluorouracil and epirubicin. The HBOT was administered along with the chemotherapy in 3 sessions in each cycle at graded pressures in each sessions. Ultrasound evaluation of patients was carried out and breast tumour size was measured after every cycle of HBOT. All the patients were operated after 3 cycles of chemotherapy and modified radical mastectomy was carried out. The response of therapy was recorded in both the groups. Patients receiving HBOT achieved significantly higher percentage reduction of tumour volume (43.1%) and the largest dimension (80.21%) (p < 0.0001) compared with those receiving chemotherapy alone. Trial registry: CTRI/2019/03/018258
Hyperbaric oxygen therapy (HBO) can increase the radiosensitivity of tumors, and there is evidence to suggest that HBO also increases the sensitivity of tumors to alkylating agents. Additionally, there are reports showing that HBO can accelerate angiogenesis and tumor growth. To address these issues, Takiguchi et al. observed the effects of HBO and 5-FU on tumors using S-180 tumor-bearing mice. Animals in the monotherapy groups were administered 0.75 mg 5-FU per animal, 6 times a week, while animals in the HBO group received oxygen at 2 ATA for 90 minutes, 6 times a week, for a total of 17 times. In the combination therapy group, HBO treatment was administered immediately after 5-FU injection. The results showed that in the control group, tumor diameter increased by 277.8% throughout the treatment period, while in the HBO monotherapy group, it increased by 244.1%, in the 5-FU monotherapy group, it increased by 182.7%, and in the combination therapy group, it increased by 138.5%.
Radiation brachial plexopathy is a refractory complication caused by radiotherapy in early-stage breast cancer, especially chronic nerve pain and limb paralysis. It is well-known that HBO can promote the recovery of ischemic tissues caused by radiotherapy, but there are no reports on radiation brachial plexopathy. Pritchard et al. conducted a study on volunteers with brachial plexopathy. 34 volunteers were randomly divided into an HBO group and a control group. The HBO group received 100 minutes of oxygen inhalation in a multi-person chamber, a total of 30 times over 6 weeks; the control group inhaled the equivalent of 100% oxygen at sea level. Using a double-blind method, all volunteers and relevant personnel were unaware of the treatment. Warmth detection threshold was used as the observation index. The results of neurophysiological experiments showed that before treatment, the affected hand in both groups was abnormal compared to the normal hand, and there was no statistically significant difference between the two groups within 12 months after treatment. However, the condition of two patients in the HBO group with lymphedema improved significantly.
After breast-conserving surgery for breast cancer, women who undergo radiation therapy often experience various symptoms. In most cases, breast problems are not further treated, and symptoms such as pain, erythema, and edema can persist for several years, affecting the patients' quality of life. HBO has a therapeutic effect on late radiation-induced injuries, but its efficacy in treating late sequelae of breast cancer, such as Carl et al. observed the effects of HBO on these sequelae. Of the 44 symptomatic patients after breast-conserving surgery, 32 received HBO treatment in a multi-person chamber at 2.4 ATA for 90 minutes, 5 times a week, with an average of 25 times. Twelve patients were in the control group and received no treatment. The changes in the radiation-treated breast area before and after HBO treatment were scored using the modified LENT-SOMA scale. The results showed that HBO treatment significantly reduced pain, edema, and erythema in patients, but showed no significant changes in fibrosis and capillary dilation. Seven patients had their symptoms disappear after HBO treatment, while all 12 patients in the control group continued to experience pain.
Radiation therapy not only damages bones and soft tissues, but can also damage the brain. The good therapeutic effects of HBO on radiation-induced tissue injuries have generated interest in using HBO to treat radiation-induced brain injuries. Chuba observed the cases of 10 patients with radiation-induced brain injuries treated with HBO. All patients developed new or aggravated neurological abnormalities and imaging changes after radiation therapy, and postmortem examinations in 8 patients revealed brain necrosis. HBO treatment was administered 20-30 times, at pressures ranging from 2.0 to 2.4 ATA, and each session lasted 90 minutes to 2 hours. As a result, all patients showed stabilization or improvement in symptoms and/or imaging findings. Four patients died due to tumor progression; five surviving patients showed improvements in clinical and imaging findings, and one patient survived with a tumor.