Three Studies Reveal Green Tea Shows Cancer Survival Signals

Written by Justus R. Hope on July 13, 2026. Posted in Current News

While reviewing literature for an upcoming article, I encountered three studies that yielded surprising results. Each included a caveat similar to: “The study was not designed to show the agent improved cancer survival, however…”

Despite this, the first two trials revealed an unexpected and substantial clinical benefit: a significant increase in tumor shrinkage.

The first study investigated the use of epigallocatechin gallate (EGCG)—the active compound in green tea—to reduce radiation-induced esophagitis in patients with esophageal cancer. In the past, oncologists have cautioned against using antioxidants in patients with active cancer, fearing that these supplements might protect the tumor from the oxidative damage intended by radiation therapy.

Addressing this concern was the primary motivation behind a series of Phase I trials conducted in China. These studies were designed as safety evaluations. Their goal was to demonstrate that patients could better tolerate radiation therapy when taking concurrent EGCG, without the antioxidant properties of the green tea extract inadvertently compromising the tumor’s response to the treatment.

These two studies were designed to show that EGCG did not worsen the response to radiation [and chemotherapy] treatment. But quite unexpectedly, the EGCG came perilously close to showing a survival advantage. And as we know, showing a cancer survival advantage by a cheap, repurposed drug or supplement is grounds for getting your study retracted.

The Unexpected Benefits of the Chinese EGCG Trials

First, after a 5-year follow-up, researchers confirmed that EGCG did not impair the esophageal tumor’s response to radiation. Instead, the EGCG group experienced multiple clinical advantages—most notably reduced pain, a decrease in severe esophagitis, and an exceptional Objective Response Rate (ORR) of 86.3%. (In oncology, ORR specifically measures the percentage of patients whose tumors significantly shrink or completely disappear following treatment).

Second, the same research team in Shandong, China, replicated this approach for lung cancer patients, again using EGCG to prevent radiation-induced esophagitis. Remarkably, the 5-year follow-up in this cohort, once again, demonstrated a powerful Objective Response Rate of 84.6%.

Below are a detailed summary and comparison of the Objective Response Rates.

1. The Shandong Esophageal Cancer Study

Study Title: Phase II Trial of Epigallocatechin-3-Gallate in Acute Radiation-Induced Esophagitis for Esophagus Cancer (published 2020) & 5-Year Follow-up (2021).
Study Design: A prospective Phase II study of 38-51 (depending on follow-up group) patients with esophageal cancer receiving definitive chemoradiotherapy or radiotherapy. Patients were given an oral EGCG solution to swallow when esophagitis symptoms began.
Toxicity Results: EGCG produced a statistically significant reduction in esophagitis-related pain, dysphagia, and overall Radiation Therapy Oncology Group (RTOG) toxicity scores across all 6 weeks.
Tumor Efficacy / ORR: The Objective Response Rate (ORR) was impressively high at 86.3%.
Survival: 1-year OS was 74.5%, 2-year was 58%, and 3-year was 40.5%.

2. The Shandong Lung Cancer Study

Study Title: A prospective, three-arm, randomized trial of EGCG for preventing radiation-induced esophagitis in lung cancer patients receiving radiotherapy (published 2019/2020).
Study Design: 83 patients with locally advanced/advanced Non-Small Cell Lung Cancer (NSCLC) and Small Cell Lung Cancer (SCLC) receiving concurrent chemoradiotherapy. Patients were randomized into three arms: prophylactic EGCG, therapeutic EGCG, and a control arm (conventional treatment).
Toxicity Results: Oral EGCG effectively alleviated acute radiation esophagitis without obvious side effects, with prophylactic EGCG having a slight advantage over therapeutic use.
Tumor Efficacy / ORR: In the 5-year follow-up specifically breaking out the SCLC lung cancer cohort, the ORR for the EGCG group was 84.6% (95% CI roughly 65%–95%) compared to only 50% (95% CI roughly 25%–75%) in the control group. This yielded a statistically significant P-value of 0.045.
Survival: At the 5-year data cut-off, there was a numerical trend toward better progression-free survival in the EGCG group (33% vs. 9.3%), but this difference was not statistically significant due to the small sample size.
While the initial response was profound, 5-year overall survival (OS) for the lung cohort remained statistically similar between the two groups (30.3% with EGCG vs. 33.3% conventional), reflecting the aggressive relapse nature of SCLC despite high initial response rates.

Comparison Analysis

1. Consistency in Radio sensitization (ORR)
The most striking finding is the consistency of the Objective Response Rate across two entirely different types of malignancies located in the thoracic cavity.

Esophageal Cancer ORR: 86.3%
Lung Cancer (SCLC) ORR: 84.6%

This consistency suggests a universal, pan-tumor mechanism of action when EGCG is paired with radiation. Rather than merely acting as a radioprotector for the healthy mucosa, EGCG simultaneously acts as a potent radiosensitizer for the tumors.

2. Mechanistic Explanation for the ORR Consistency
Recent mechanistic studies clarify why EGCG drives such high response rates in both cancers:

In Lung Cancer, radiation causes an inflammatory surge (IFN-γ) that triggers the tumor to upregulate PD-L1, hiding from the immune system.
EGCG blocks this via JAK2/STAT1 inhibition, breaking the PD-1/PD-L1 axis and allowing T-cells to aggressively shrink the irradiated tumor.
In Esophageal Cancer, chronic inflammation from radiation heavily activates the NF-κB pathway, which drives the expression of Syndecan-4 (SDC4), causing rapid tumor proliferation. EGCG is proven to block NF-κB nuclear translocation, shutting down this highly specific IL1β-NFκB-SDC4 proliferation axis in esophageal cells.

3. The Difference in Long-Term Survival Ramifications
While both cancers experienced massive initial tumor shrinkage (>84% ORR), the survival trajectories diverge based on the biology of the diseases:

In Esophageal cancer, localized tumor control is heavily tied to survival, as local obstruction and invasion are primary causes of morbidity. The 86.3% ORR translated to a solid 40.5% 3-year survival.
In SCLC (Lung), the disease is systemically micro-metastatic. The 84.6% ORR reflected fantastic local/regional control by the radiation + EGCG. However, the 5-year progression-free survival (PFS) was notably higher in the EGCG group at 33% versus 9.3% but due to the small sample size did not reach statistical significance.
Micro-metastases eventually caused relapse, leading to no significant difference in 5-year OS.

Conclusion

The Shandong studies definitively prove that oral EGCG transcends its role as a mere palliative treatment. It offers a unique dual benefit: protecting healthy tissue from oxidative damage while cutting off critical inflammatory escape pathways (PD-L1 and NF-κB) in both esophageal and lung tumors. Ultimately, this dual action yields a consistent ~85% Objective Response Rate, establishing EGCG as a highly effective, non-toxic radiosensitizer.

Other Studies that Show EGCG is a Natural Dual Checkpoint Inhibitor of PD-L1 & PD-1

Synthesis of Findings

Dual Immune Checkpoint Blockade: The literature strongly supports that EGCG acts as a natural, dual-action immune checkpoint inhibitor. Menon (2021) and Rawangkon (2018) demonstrated that EGCG strips tumors of their PD-L1 defense mechanism by blocking the JAK/STAT pathway.
Concurrently, Li (2024) proved that EGCG also suppresses the PD-1 receptor on host T-cells, keeping the host’s immune cells active through NF-kB inhibition.
Potent NF-κB Inhibition: Across multiple tissue types (lung cancer, macrophages, endothelium), EGCG is shown to be a potent inhibitor of NF-κB. It achieves this by preventing the nuclear translocation of the p65 subunit and blocking its ability to bind to DNA.
Clinical Ramifications for ORR: By simultaneously shutting down tumor-promoting inflammation (NF-κB) and breaking the immune-exhaustion axis (PD-1/PD-L1), EGCG creates a highly favorable tumor microenvironment for cytotoxic T-cells to aggressively attack the tumor. This mechanistic profile directly explains the high initial Objective Response Rates (~85%) seen in the Shandong clinical trials when EGCG is used alongside radiation therapy.

The Third Study

The third study is one that left me stunned. Allow me to introduce the study findings beginning with this quote from Professor Ben Williams:

“Because cancer cells have a genetic structure different from normal cells, they generate foreign proteins that in principle should be detected by the immune system and evoke the same type of immune reaction as any foreign virus or bacteria. This basic fact suggests that augmenting one’s immune system might be an effective approach to cancer treatment. Such an approach has an immediate appeal because it is surely preferable to reinforce the immune system than to poison the entire body in the hope the cancer cells will be killed before the body is depleted of vital resources.”

Diagnosed with glioblastoma in 1995, Professor Williams predated the complete characterization of the PD-1/PD-L1 pathways and modern understandings of tumor immunology. Nevertheless, he successfully utilized a repurposed drug regimen anchored by three immune-modulating agents: Vitamin D3, PSK, and melatonin.

This intervention facilitated an extraordinary 30-plus-year survival in a cancer with a median survival of 15 months. His early adoption of immune-enhancing natural agents and repurposed drugs highlights exceptional scientific foresight, almost anticipating the breakthrough immunotherapeutic strategies that define current cancer treatments.

Ben Williams’ survival was rooted in his understanding of the immune system. That brings us to the core subject of our third study, which focuses on an agent that similarly manipulates the tumor microenvironment.

This specific agent holds profound personal significance for me, as it signals that we are closing in on a viable treatment for the disease that claimed my father. Dr. Marik and I have debated extensively over whether to include this agent in our protocols. Now, thanks to the groundbreaking results of this recently published study, I can safely say it belongs on the list.

source justusrhope.substack.com