Epub 2014 May 26.Fritz H1, Flower G2, Weeks L2, Cooley K3, Callachan M1, McGowan J1, Skidmore B1, Kirchner L4, Seely D5.Author information1Canadian College of Naturopathic Medicine, Toronto, Ontario, Canada.2Ottawa Integrative Cancer Centre, Ottawa, Ontario, Canada.3Canadian College of Naturopathic Medicine, Toronto, Ontario, Canada University of Toronto, Toronto, Ontario, Canada.4Carp Ridge Natural Health Clinic, Carp, Ontario, Canada.5Canadian College of Naturopathic Medicine, Toronto, Ontario, Canada Ottawa Integrative Cancer Centre, Ottawa, Ontario, Canada Ottawa Hospital Research Institute, Ottawa, Ontario, Canada dseely@oicc.ca.AbstractBACKGROUND: Intravenous vitamin C (IVC) is a contentious adjunctive cancer therapy, widely used in naturopathic and integrative oncology settings. We conducted a systematic review of human interventional and observational studies assessing IVC for use in cancer patients.METHODS: We searched MEDLINE, EMBASE, The Cochrane Library, CINAHL, and AMED from inception to April 2013 for human studies examining the safety, effectiveness, or pharmacokinetics of IVC use in cancer patients.
RESULTS: Of 897 records, a total of 39 reports of 37 studies were included: 2 randomized controlled trials (RCTs), 15 uncontrolled trials, 6 observational studies, and 14 case reports. IVC dosing ranged from 1 g to more than 200 g ascorbic acid per infusion, typically administered 2 to 3 times weekly. IVC does not appear to increase toxicity or interfere with antitumor effects of gemcitabine/erlotinib therapy or paclitaxel and carboplatin. Based on 1 RCT and data from uncontrolled human trials, IVC may improve time to relapse and possibly enhance reductions in tumor mass and improve survival in combination with chemotherapy. IVC may improve quality of life, physical function, and toxicities associated with chemotherapy, including fatigue, nausea, insomnia, constipation, and depression. Case reports document several instances of tumor regression and long-term disease-free survival associated with use of IVC.CONCLUSION: There is limited high-quality clinical evidence on the safety and effectiveness of IVC.
Go to Patient Version This cancer information summary provides an overview of the use of high-dose vitamin C (also known as ascorbate or L-ascorbic acid) as a treatment for people with cancer. This summary includes a brief history of early clinical trials of high-dose vitamin C; reviews of laboratory, animal, and human studies; and current clinical trials. This summary contains the following key information: Vitamin C is an essential nutrient with redox functions at normal physiologic concentrations. High-dose vitamin C has been studied as a treatment for cancer patients since the 1970s. Laboratory studies have reported that high-dose vitamin C has redox properties and decreased cell proliferation in prostate, pancreatic, hepatocellular, colon, mesothelioma, and neuroblastoma cell lines. Two studies of high-dose vitamin C in cancer patients reported improved quality of life and decreases in cancer-related side effects. Studies of vitamin C combined with other drugs in animal models have shown mixed results.
Intravenous vitamin C has been generally well tolerated in clinical trials. Many of the medical and scientific terms used in this summary are hypertext linked (at first use in each section) to the NCI Dictionary of Cancer Terms, which is oriented toward nonexperts. When a linked term is clicked, a definition will appear in a separate window. Reference citations in some PDQ cancer information summaries may include links to external Web sites that are operated by individuals or organizations for the purpose of marketing or advocating the use of specific treatments or products. These reference citations are included for informational purposes only. Their inclusion should not be viewed as an endorsement of the content of the Web sites, or of any treatment or product, by the PDQ Integrative, Alternative, and Complementary Therapies Editorial Board or the National Cancer Institute.IV (intravenous) vitamin C therapy has already been clinically proven to markedly improve quality of life for cancer patients, but a new landmark study has shown for the first time it can reduce inflammation and tumour markers in prostate cancer and breast cancer patients.
The science behind IV vitamin C as a cancer therapy is now advancing faster than ever before with six clinical trials currently underway worldwide, including colorectal, prostate, pancreatic and other cancers. Dual role of IV vitamin C for cancer: cytotoxicity and inflammation In lab studies, high-dose vitamin C has proven to be potently cytotoxic to a wide variety of cancer cell lines as well as to boost the cytotoxicity of several common chemotherapy drugs. This has been confirmed in animal studies, where IV vitamin C decreases the growth rates of liver, ovarian, pancreatic, and glioblastoma tumors with dosages easily achievable in humans. But beyond directly poisoning cancer cells, there is another role for vitamin C to play in treating cancer: the reduction of inflammation. Recent research has shown that greater inflammation in cancer patients is associated with poor prognosis. This may be because key features of the inflammatory environment (infiltrating leucocytes, pro-inflammatory cytokine build-up, tissue remodelling and angiogenesis) may actually facilitate cancer development.
With this in mind, one of the leading alternative medicine clinics in the USA designed a trial to test the ability of IV vitamin C to reduce key inflammation markers as well as tumour markers in patients with prostate, breast and other cancers. This trial included 45 patients aged 47-85 years, with an average age of 68. The treatments included vitamin C infusions of 25 to 50 grams, up to three times per week. The median follow-up on patients was 7.2 years (maximum of 18 years). It should be noted that most patients had already been treated by standard therapies. The total number of vitamin C infusions given to any one patient ranged from 1 up to 102. Inflammation markers reduced in 76% of cancer patients IV vitamin C therapy was successful in reducing C Reactive Protein (CRP) levels in 76% of all patients in the trial. This is significant, as CRP is a well-established marker for inflammation. By the end of the trial, the average patient saw a drop in CRP levels of 80% (for patients who started the trials with above-normal CRP levels).
In addition, for a more detailed picture, serum levels of pro-inflammatory cytokines were measured for 11 patients. Of these 11 patients, 100% saw large reductions in these cytokines after their treatments. Some important trends emerged from the trial. Firstly, patients who had more IV vitamin C treatments tended to have a better response. Second, patients who began the therapy at an earlier stage of their disease had better response compared to those with more aggressive, metastatic cancer. Finally, and perhaps most importantly, patients who saw reductions in inflammation markers usually also saw reductions in tumour markers—especially for breast and prostate cancer. Tumour markers decreased for most prostate cancer and breast cancer patients Most impressive with this trial was that PSA levels decreased in 77% of prostate cancer patients while 73% of breast cancer patients saw decreases in CA27.29/CA15.3 (cancer antigen) and/or CEA (carcinoembryonic antigen) after their treatments.