Authors: Yuen Chuen Fong Raymond1; Stephanie Anne Loke Mun See2; Yuen Tin Wei3
1Principal Doctor, Hosanna Clinic ; 2Researcher, Hosanna Clinic ; 3Medical Student, National University of Singapore


This is a single case report that documents the benefits of high-dose intravenous vitamin C (IVC) therapy in keeping high recurrence of late-stage ovarian cancer at bay.


Ovarian cancer is the fifth most common type of cancer in Singapore (National Registry of Diseases Office, 2017) and has the seventh highest cancer mortality rate in females in 2010-2014 (NRDO, 2015). Incidence rates of ovarian cancer in Singapore are higher than that of Australia, Japan, China and India but lower than the United Kingdom (NRDO, 2015).

Ovarian cancer often has no symptoms in its early stages. Four in five ovarian cancer patients (Alteri et al., 2018) in the United States are diagnosed at the advanced stages where the disease has already spread into the abdominal cavity. Although the five-year survival rate for patients diagnosed with ovarian cancer is 47.4 percent (2008-2014) in the United States (Noone et al., 2018), late-stage patients have a disproportionately high rate of recurrence with stage III and IV patients recording 70 to 90 percent and 90 to 95 percent recurrence rates respectively (Ovarian Cancer Research Fund Alliance).

In the United States, there is no lack of medical research documenting the beneficial effects of IVC therapy as a form of cancer treatment. It’s clinical use is increasing amongst integrative, functional and orthomolecular medicine practitioners.

IVC therapy was first applied on cancer patients by Linus Pauling (Cameron & Campbell, 1974). IVC therapy has a controversial history, due in part to subsequent clinical trials conducted at the Mayo Clinic which failed to demonstrate any benefit (Moertel et al., 1985; Creagan, Moertel & O’Fallon, 1979). However, it was later discovered that although the similar doses were used in both the Pauling-Cameron and Mayo Clinic studies, the former administered the vitamin C (ascorbic acid) intravenously while the latter administered the vitamin C orally, leading to drastically different outcomes (Cameron, 1991; Padayatty, Sun & Wang, 2004).

Studies undertaken by the United States of America National Institute of Health showed that vitamin C demonstrated cytotoxicity in cancer cells at high serum levels and is achievable only through intravenous administration (Padayatty, 2004). Furthermore, studies have also shown that oral administration of large doses of vitamin C increases serum levels to a maximum of 220 μmol/L while serum levels can reach 14,000 μmol/L via intravenous administration (Padayatty, 2004). Concentrations of 1,000 to 5,000 μmol/L are selectively cytotoxic to tumour cells in vitro (Padayatty, 2004; Chen, Espey, & Krishna, 2005).

In Singapore, IVC therapy is better known as a form of aesthetic treatment for skin whitening and rejuvenation rather than as a type cancer therapy primarily due to a lack of supporting data from controlled clinical trials. Many Singaporean cancer patients are well aware of the negative side effects of conventional cancer treatment, causing some to opt for alternative treatments such as Chinese medicine, herbal medicine, acupuncture, bio-resonance therapy, Gerson therapy, macrobiotic diets and raw food diets to complement conventional cancer treatments (Yuen, Chong & Lim, 2016). Since many of these alternative treatments are not well documented, their effectiveness remains unknown.

Patient Adopted High Dose IVC Therapy Right After Surgery and Chemotherapy

The patient, a 48-year-old Chinese woman, was diagnosed with stage IV ovarian cancer in March 2013. A well-defined rounded lesion with mild enhancing rim was found situated in a posterolateral manner to the left submandibular gland and lateral to the left carotid vessels. Soon after diagnosis, the patient underwent oophorectomy and hysterosalpingectomy surgeries, followed by six cycles of chemotherapy and radiotherapy. Post-treatment, blood tests conducted on September 21, 2013 indicated that her tumour markers were within the normal range, while her haemoglobin levels stood at 9.7g/dL (12.0-16.0g/dL) and white blood cell count at 2.9×109/L (4-10×109/L).

Although in remission, her oncologist warned that late-stage ovarian cancer patients have a 70 percent probability of a relapse within the first year. The despondent patient was determined not to give up, and in a bid to prevent a relapse, she decided to give IVC therapy a try in November 2013 to repair and restore her immune system.

The patient underwent an initial daily program of high-dose IVC starting from a dosage of 25g and progressively increasing up to 75g per day over a period of 28 days. Subsequently, the patient maintained an IVC regiment of 75g per day, two times a week for a period of twelve months and reduced to once a week for six months. After this, the treatment was further reduced to one dose every two weeks for another six months and finally to a maintenance dose every three or four weeks until five years post-operation.

To complement the IVC treatment, the patient adopted a plant-based diet, drank raw vegetable juices and consumed additional nutritional supplements (Yuen et al, 2016). In addition, the patient adopted the modified Gerson protocol for liver detoxification and exercised two to three times per week.

Her progress was monitored every three to six months by her oncologist and Dr Yuen via pelvic ultrasounds, blood tests for ovarian cancer markers, renal and liver functions, complete blood profiles as well as inflammation markers.


A blood test conducted in March 2015 showed an increase in haemoglobin levels to 11.3 g/dL, while white blood cell count increased to 5.8×109/L. Even though the red and white blood cell counts were in the lower end of the reference range, the patient’s health improved and she experienced a better quality of life.

A pelvic ultrasound conducted in March 2015 showed no pelvic mass or free fluid with an unremarkable urinary bladder status. A subsequent blood test on April 20, 2015 showed normal CA125 tumour marker (cancer antigen) of 6.1 U/mL (<36 U/mL). On April 12, 2018, she had a CA125 of 3.0 U/mL, while MRI scans showed no cancer growth and no abnormal pelvic mass was observed.

It has been more than five years since her completion of conventional cancer treatment, and the patient has not experienced a relapse of cancer. She currently enjoys a good quality of life and has certainly beaten the odds.


Pharmacology: Vitamin C is a water-soluble antioxidant that is important for the proper functioning of the immune system. Dr Hugh Riordan, who founded the Riordan Clinic in 1975, noted that in high doses vitamin C has positive effects on many chronic illnesses (Riordan, 1988; Carr & McCall, 2017).

It is undisputed that cancer cells absorb glucose at much higher rates than normal cells. PET and CT scans – common cancer diagnostic tools – involve injecting radioactive glucose into patients to identify and evaluate cancer metastases in their bodies.

The molecular structure of vitamin C is remarkably similar to glucose. When high doses of vitamin C are administered intravenously, it becomes a pre-oxidant and cancer tumour cells mistakenly absorb vitamin C as its food source. There is increasing evidence that IVC is selectively toxic to some types of tumour cells by inducing tumour cell apoptosis, inhibiting angiogenesis and reducing inflammation (Riordan Clinic Research Institute, 2015). Vitamin C at normal physiological concentrations is a water-soluble antioxidant (Riordan Clinic Research Institute, 2015). However, at high concentrations (350- 450 mg/dL), vitamin C dissociates in the extracellular fluid to become an ascorbate radical (AscH−), causing iron to be reduced to the ferrous form (AscH− + Fe3+ → _Fe2+ + AscH− + H+). The ferrous iron then reacts with oxygen, producing a superoxide anion (O2−), which reacts with hydrogen to form H2O2 (Riordan Clinic Research Institute, 2015). As the concentration of H2O2 increases in these tumour cells, they are vulnerable to the cytotoxic effects of H2O2, and hence inducing apoptosis and tumour cells are killed (Chen et al., 2005; Fritz et al., 2014; Putchala et al., 2010).

Under the Riordan IVC protocol, the Riordan Clinic advocates a concentration of 0.1 to 1.0g of ascorbic acid per kilogram of body mass (Riordan Clinic Research Institute, 2013b).

Effects of IVC Therapy: IVC therapy is relatively safe compared to radiotherapy and chemotherapy.

The patient experienced temporal healing reactions such as mild fever and vomiting during and up to two hours after the IVC therapy. Endotoxins produced by the necrosis of harmful cells create healing responses similar to the Jarish-Herzheimer reaction. Such healing responses may manifest as fever, chills, strong body odour and pimples on the body (Pound & May, 2005). These reactions occur within two hours after IVC therapy, are transient, reversible and are typically resolved after two to three hours.

By contrast, the patient sustained prolonged side effects such as dryness in the mouth, eyes, and nose, muscle and bone aches, toothache, hair loss, loss of taste, frequent nosebleeds, lethargy, weakness, and low immunity during her prior chemotherapy and radiotherapy protocols.

Against the odds of a 90 to 95 percent recurrence rate for stage IV ovarian cancer within the first year, the patient did not experience a relapse. As of May 2018 – five years after her initial diagnosis – blood tests and scans indicate that her cancer did not relapse and she is in complete remission. The patient now enjoys a good quality of life, loves travelling and is gratefully living out a purposeful new lease of life.

Such results can be attributed to the benefits of IVC therapy and is not a coincidence.

Benefits of High-Dose Vitamin C as an Anti-cancer Agent: High doses of vitamin C has been widely documented to effect cytotoxic and anti-metastatic actions on malignant cell lines (Chen et al., 2005) and can enhance chemotherapy by reducing chemo toxicity in ovarian cancer (Yan et al., 2014).

The treatment improves the quality of life for cancer patients (Kuiper et al., 2014; Carr, Vissers & Cook, 2014; Yeom, Jung & Song, 2007), prolongs survival (Cameron & Pauling, 1976; Cameron & Pauling, 1978), potentiates chemotherapy and reduces the side effects of chemotherapy (Jung et al., 2016; Hoffer et al., 2015).

It is proven safe even in high doses (Schoenfeld et al., 2017; Stephenson et al., 2013) and enhances the immune systems of cancer patients to fight against cancer (Maggini, et al., 2017; Carr & Maggini, 2017; Pavlovic, 2010; Strohle, Wolters & Hahn, 2011). It also raises the host resistance against cancer (Gonzalez & Miranda-Massari, 2014), prevent the cancer from further spreading (Schleich et al., 2013). It is an epigenetic modulator of genes with a key role in cancer development (Shenoy, Bhagat & Nieves, 2017; De Francesco et al., 2017; University of Salford, 2017).


Compared to conventional chemotherapy and radiotherapy, IVC therapy, in combination with a diet and supplement regimen, appears to help prevent the recurrence of stage IV ovarian cancer. The combined use of IVC therapy, diet and supplemental nutrition reduces inflammation, improves survival rate, enhances quality of life and prolongs life expectancy in ovarian cancer patients without all the negative side effects that accompany conventional cancer treatments.

IVC therapy has also been co-administered with conventional therapy without impairing the response. It is safe for most patients and relatively inexpensive. IVC therapy has the potential to become an important chemotherapeutic method to combat cancer. This, however, can take place only through further research and clinical study.

Authors’ Notes

This article was written as an observational study of one patient.

Declaration of Conflicting Interests: The authors declare there are no conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding: The authors did not receive any paid honoraria, financial support nor external grants for the research, authorship and/or publication of this article from any pharmaceutical companies nor any other organizations.

Acknowledgements: The authors extend our heartfelt thanks to the ovarian patient and her husband for permitting us to publish and share her medical information. We also wish to acknowledge participants in the Hosanna Clinic Cancer Patients’ Support Group for their encouragement to continue the pursuit of safe and less invasive cancer therapies and to spread the word. Finally, our gratitude and appreciation goes to the dedicated staff of Hosanna Clinic – Sujeewa, Lynn, Tharidu and Shalika – who tirelessly and patiently provided much needed care, support and love to our cancer patients.


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