A global review examining reported cases of cancer following Covid vaccination was published earlier this month, just as the medical journal hosting it was hit by a cyberattack that has since taken the site offline.
The study appeared in the peer-reviewed journal Oncotarget on January 3 and was authored by cancer researchers from Tufts University in Boston and Brown University in Rhode Island.
In the review, researchers analyzed 69 previously published studies and case reports from around the world, identifying 333 instances in which cancer was newly diagnosed or rapidly worsened within a few weeks following Covid vaccination.
The review covered studies from 2020 to 2025 and included reports from 27 countries, including the US, Japan, China, Italy, Spain, and South Korea. No single country dominated, suggesting the observed patterns were reported globally.
The authors emphasized that the review highlights patterns observed in existing reports, but does not establish a direct causal link between vaccination and cancer.
Days after publication, Oncotarget’s website became inaccessible, displaying a ‘bad gateway’ error that the journal attributed to an ongoing cyberattack.
The journal reported the incident to the FBI, noting disruptions to its online operations.
In social media posts, one of the paper’s authors, Dr Wafik El-Deiry of Brown University, expressed concern that the attack disrupted access to newly published research.
‘Censorship is alive and well in the US, and it has come into medicine in a big, awful way,’ El-Deiry wrote in a post on X.
A new medical review has uncovered cancerous growths forming just days and weeks after individuals received the Covid-19 vaccine
The new study was published by the journal Oncotarget, which has been attacked by hackers, preventing readers from accessing the research
The FBI told Daily Mail that it ‘neither confirms nor denies the existence of any specific investigation’ into a cyberattack on Oncotarget.
The Daily Mail has reached out to Oncotarget for comment on the cyberattack investigation.
In a post that can no longer be accessed because of the website hacking, Oncotarget noted disruptions to the availability of new studies online. Although they did not accuse a specific group of wrongdoing, the journal alleged without evidence that the hackers may be connected to the anonymous research review group PubPeer.
The researchers alleged that the cyberattack targeted Oncotarget’s servers to disrupt the journal’s operations and prevent new papers from being properly added to the site’s index.
The message was shared on social media by El-Deiry before the website crashed, with the doctor adding, ‘Censorship of the scientific press is keeping important published information about Covid infection, Covid vaccines and cancer signals from reaching the scientific community and beyond.’
In a statement to the Daily Mail, PubPeer declared: ‘No officer, employee or volunteer at PubPeer has any involvement whatsoever with whatever is going on at that journal.’
PubPeer is an online platform where researchers can anonymously comment on peer-reviewed scientific papers after they’ve already appeared in journals.
Its stated goal has been post-publication peer review, meaning people discuss, critique, or point out potential issues in studies that have already passed the usual pre-publication checks.
Many of the cases involved tumors growing near the injection sites in the arm (Pictured), but the study could not definitively say the Covid vaccine caused cancer
Study author Wafik El-Deiry claimed his work was being ‘censored’ and shared a post from the study journal alleging the attack was carried out by fact-checkers of published studies
The cyberattack appeared to hit around December 2025, as the site began glitching and slowing down, but shortly after the paper was published, it went offline.
Hackers can shut down websites using methods such as a DDoS attack, which floods the victim’s server with fake traffic to overwhelm it and make it crash, or by directly hacking into their systems to block access, often done remotely through weak points in the site’s internet security.
When this happens, websites may show error messages like ‘Bad Gateway’ or ‘Service Unavailable,’ making it temporarily inaccessible or slow for users, but it doesn’t mean everything is permanently deleted
The studies on Oncotarget, including El-Deiry’s, should be able to be recovered or accessible once the attack has ended.
Some of the studies El-Deiry looked at featured massive datasets, including one from the US, which examined 1.3million military service members and found a rise in some blood cancers after 2021, when Covid vaccines rolled out.
The researchers noted that the studies reported various types of cancer following vaccination, but emphasized that these findings do not establish a causal link between vaccines and cancer.
Wafik El-Deiry and co-author Charlotte Kuperwasser, a researcher at Tufts University School of Medicine in Boston, also found that some case reports referenced in the review included localized reactions near injection sites, which the authors suggested warranted further study to understand any potential biological mechanisms.
The study revealed 333 cases of cancer being diagnosed in the weeks and months following Covid-19 vaccinations or booster shots (Stock Image)
The paper also uncovered sudden flare-ups of slow-growing cancers that had been stable before receiving the Covid jab, and incidents where the vaccine appeared to ‘wake up’ certain viruses that can lead to cancer, like human herpesvirus 8.
Major study populations, including one review of 300,000 people in Italy and one examining 8.4million people in South Korea, uncovered higher cancer rates of thyroid, colon, lung, breast, and prostate cancers among vaccinated individuals.
However, the findings varied by age, sex, vaccine type, and dose, with patients taking more doses and boosters of the Covid vaccine later experiencing higher rates of some cancers, such as gastric and pancreatic.
Adults younger than 65 appeared to have a higher risk of developing thyroid and breast cancers after vaccination, while seniors over 75 had a higher risk of prostate cancer.
‘These findings underscore the need for rigorous epidemiologic, longitudinal, clinical, histopathological, forensic, and mechanistic studies to assess whether and under what conditions COVID-19 vaccination or infection may be linked with cancer,’ the team wrote in their study, which they shared online.
