A new peer-reviewed study published in EXCLI Journal in July 2025 has reported a 23% increase in cancer diagnoses within six months of COVID-19 vaccination, raising serious questions among medical commentators and fueling an ongoing debate about vaccine safety.
The large-scale population study, conducted in Italy's Pescara province, followed nearly 300,000 residents aged 11 and older between June 2021 and December 2023.
Using official National Health System data, researchers compared cancer hospitalization rates between vaccinated and unvaccinated individuals, while adjusting for age, sex, pre-existing conditions, prior cancers, and prior COVID-19 infections.
Dr. John Campbell, a retired nurse educator and medical commentator, described the findings as "real data and quite concerning." He stressed that the results carried strong statistical weight, noting "only one chance in a thousand that this result arose by chance."
While cancer risks rose, the study found that vaccinated individuals had a lower risk of all-cause mortality compared to the unvaccinated.
Researchers attributed this to the "healthy vaccinee bias" -- the idea that people who get vaccinated are generally more health-conscious, potentially masking or underestimating cancer risks tied to vaccination.
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The authors wrote: "The healthier lifestyle that is typically associated with vaccination may reduce the risk of lifestyle-associated carcinomas ... leading to an underestimation of the potential negative impact of vaccination on hospitalization due to cancer."
Campbell outlined several possible biological mechanisms linking COVID-19 vaccines to increased cancer risk: Chronic inflammation from ongoing spike protein production; Autoimmune reactions leading to tissue damage; DNA contamination and mutations, which could disrupt tumor-suppressor genes; Rogue proteins formed through frameshifting
"These mechanisms are biologically plausible," Campbell said, though he cautioned that more long-term research is needed.
Campbell criticized governments for withholding detailed vaccination and health outcome data, calling it "a cover-up" and "quite outrageous." He argued that without open access to data, it will take "10 to 20 years" to fully understand the vaccine's long-term impact on cancer development.
The findings have ignited intense debate within the medical community.
While some experts view the study as a groundbreaking warning sign, others stress that the observational nature of the research cannot establish causation and must be weighed against evidence of COVID-19 vaccines reducing severe illness and deaths from the virus.