Intravenously administered vitamin C as cancer therapy: three cases.
Level 4 - case-series / case-control
Case series (retrospective evaluation of three clinical cases)
PubMed 16567755 · doi:10.1503/cmaj.050346
What was done
The authors examined clinical records for three patients with advanced cancer who received high-dose intravenous vitamin C therapy, evaluated in accordance with National Cancer Institute (NCI) Best Case Series guidelines. Tumor pathology was independently verified by NCI pathologists blinded to diagnoses and treatments.
What was found
The abstract reports no specific numerical survival times, patient demographics, tumor types, or treatment regimens. It reports that all three patients had advanced, histopathologically verified cancers and achieved unexpectedly long survival times after intravenous vitamin C therapy. Pharmacokinetic context cited in the abstract indicates that oral vitamin C (18 g/d) reaches peak plasma levels of ~220 µmol/L, whereas intravenous administration reaches ~25-fold higher concentrations at the same dose, and 50–100 g infusions reach ~14,000 µmol/L, exceeding the in vitro cytotoxic threshold for cancer cells (>1,000 µmol/L).
Why it matters
Because prior negative randomized trials evaluated oral rather than intravenous vitamin C, these cases and pharmacokinetic differences support re-evaluating high-dose intravenous vitamin C in formal clinical trials.
Limits
The study is restricted to an uncontrolled series of three selected patients, making it impossible to determine causality, rule out spontaneous remission or concurrent therapies, or assess efficacy. Specific numerical survival data, cancer types, and safety outcomes are not reported in the abstract.
Cited by
- supports Intravenous vitamin C administration can produce plasma concentrations as high as 15,000 micromoles per liter.