Green tea and green tea extract in oncological treatment: A systematic review

Wiese et al., 2023 | Int J Vitam Nutr Res | Systematic Review

Citation

Wiese Fanny, Kutschan Sabine, ... Huebner Jutta. Green tea and green tea extract in oncological treatment: A systematic review. Int J Vitam Nutr Res. 2023-Feb;93(1):72-84. doi:10.1024/0300-9831/a000698

Abstract

Purpose: Teas are an essential part of traditional phytotherapy. The aim of this systematic review is to assess the clinical evidence using green tea catechins in cancer care. Methods: A systematic search was conducted searching five electronic databases concerning the effectiveness and risks of epigallocatechin gallate (EGCG) on cancer patients. Results: Seven studies with 371 patients were included. Patients were mainly suffering from breast and prostate cancer. Dosing ranged from 28 mg to 1600 mg EGCG, intervention time from 7 days to 6 months with different applications (topical 2 studies; oral 5 studies). The studies showed heterogeneous methodological quality and results leading not to conduct a meta-analysis. There was a small decrease in prostate-specific-antigen levels in one study (N=60; T0:(mean±SD) 9.6±5.2 ng/ml, T1: 8.4±4.3 ng/ml vs. T0: 9.9±8.5 ng/ml, T1: 10.0±9.0 ng/ml; p=0.04), whereas in a second study only a trend was seen. Topical green tea was as effective as metronidazole powder in reducing the odor of fungating malignant wounds (1 study; N=30) with a consequent increase in quality of life (QoL) (p<0.001), improvement of appetite (p<0.001), malodorous control (p<0.001), social activities (p<0.001). Radiotherapy-induced diarrhea was lower in the green tea intervention group compared to placebo (1 study; N=42; week 4+5: without diarrhea p=0.002). Conclusions: The studies suggest that EGCG is as effective as a local antibiotic in malodorous control and improvement of QoL of fungating malignant wounds. Green tea could be a possible complementary method for treating acute radiation-induced diarrhea. Due to limitations, further studies with higher methodological quality and larger sample sizes are needed.

Key Findings

Seven studies with 371 patients were included. Patients were mainly suffering from breast and prostate cancer. Dosing ranged from 28 mg to 1600 mg EGCG, intervention time from 7 days to 6 months with different applications (topical 2 studies; oral 5 studies). The studies showed heterogeneous methodological quality and results leading not to conduct a meta-analysis. There was a small decrease in prostate-specific-antigen levels in one study (N=60; T0:(mean±SD) 9.6±5.2 ng/ml, T1: 8.4±4.3 ng/ml vs.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 60
Age Range See abstract
Condition See abstract

MeSH Terms

  • Humans
  • Male
  • Antioxidants
  • Plant Extracts
  • Prostatic Neoplasms
  • Quality of Life
  • Tea

Evidence Classification

  • Level: Systematic Review
  • Publication Types: Journal Article, Systematic Review
  • Vertical: green-tea

Provenance


Source extracted via PubMed E-utilities API on 2026-04-09