Effect of Vitamins C and E on Cancer Survival; a Systematic Review Publisher Pubmed



Mohseni S¹ ; Tabatabaeimalazy O² ; Ejtahed HS³ ; Qorbani M⁴ ; Azadbakht L^{5, 6, 7} ; Khashayar P^{8, 9} ; Larijani B¹
Source: DARU# Journal of Pharmaceutical Sciences Published:2022

Abstract

Purpose: Association between vitamins C (VC)/ E (VE) and cancer survival is inconsistent. This systematic review is aimed to summarize trials for effects of VC/VE on cancer survival. Methods: Relevant English trials were retrieved from PubMed, Cochrane Library, Embase, Web of Science, Scopus databases, and Clinicaltrials.gov through 21/June/2022. Inclusion criteria were all trials which assessed sole/combinations intake of VC/VE on survival rate, mortality, or remission of any cancer. Exclusion criteria were observational and animal studies. Results: We reached 30 trials conducted on 38,936 patients with various cancers. Due to severe methodological heterogeneity, meta-analysis was impossible. High dose VC + chemotherapy or radiation was safe with an overall survival (OS) 182 days − 21.5 months. Sole oral or intravenous high dose VC was safe with non-significant change in OS (2.9–8.2 months). VE plus chemotherapy was safe, resulted in stabling diseases for 5 years in 70- 86.7% of patients and OS 109 months. It was found 60% and 16% non-significant reductions in adjusted hazard ratio (HR) deaths or recurrence by 200 mg/d tocotrienol + tamoxifen in breast cancer, respectively. Sole intake of 200–3200 mg/d tocotrienol before resectable pancreatic cancer was safe and significantly increased cancer cells’ apoptosis. Combination VC and VE was non-significantly reduced 7% in rate of neoplastic gastric polyp. Conclusion: Although our study is supported improvement of survival and progression rates of cancers by VC/VE, more high quality trials with large sample sizes are required to confirm. PROSPERO Registration number: CRD42020152795. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Tehran University of Medical Sciences.