Investigating claim 10 'vaccinated' nurses at Massachusetts hospital were diagnosed with brain tumors 'simultaneously'

In late March and early April 2025, a rumor circulated online that 10 "vaccinated" nurses working at the same Massachusetts hospital were diagnosed with brain tumors "simultaneously."

For example, one X user, whose March 30 post had amassed more than 257,000 views as of this writing (archived), wrote: "At Newton-Wellesley Hospital in Massachusetts, a startling cluster of brain tumor diagnoses has emerged among vaccinated nurses on the fifth-floor maternal care ward. 10 longtime staff members have been affected simultaneously, sparking alarm and raising questions about a potential link between mRNA vaccines and cancer."

The X post also included a screenshot of a March 29 article by a website called The People's Voice (TPV), which has repeatedly spread misinformation about the COVID-19 vaccines. The article's headline read: "10 Vaxxed Nurses at Massachusetts Hospital Diagnosed with Brain Tumors Simultaneously."

Although neither the X post nor the TPV article specifically stated that the 10 nurses had been vaccinated against the SARS-CoV-2 virus, such claims about mRNA vaccines often refer to the COVID-19 vaccines, which TPV has written numerous false or misleading articles about.

Examples of the rumor appeared on Facebook (archived), Instagram (archived), TikTok (archived) and Bluesky (archived). Additionally, some X posts (archived) added the claim that the nurses had all received COVID-19 vaccines. Snopes readers also emailed to ask us to check the claim.

Newton-Wellesley Hospital (NWH) confirmed via email that five staff members who had worked on the hospital's fifth floor were diagnosed with noncancerous brain tumors. The hospital did not specify whether all five staff members were nurses. Following the diagnoses, the hospital said it had carried out an investigation into environmental risks and found none that "could be linked to the development of a brain tumor." NWH also dismissed claims that the workers' vaccine statuses were linked to their brain tumor diagnoses, saying some diagnoses predated the COVID pandemic. A local union for nurses in Massachusetts disputed the hospital's investigation and was carrying out its own at the time of this writing.

Five out of 11 staff interviewed by hospital had brain tumors — none were cancerous

Though elements of the claim were true — for example, that staff at one Massachusetts hospital were diagnosed with brain tumors — other elements, such as the connection to vaccines, were not.

According to a statement sent via email, officials at NWH in Newton, Massachusetts, carried out an investigation following reports that "as many as 10 nurses" who worked on the fifth floor maternity unit were diagnosed with brain tumors.

According to a Q&A document published by NWH on April 2, the hospital interviewed 11 staff who worked on the floor. Five of the staff were found to have benign (noncancerous) brain tumors, while the remaining six had "other health concerns."

That investigation found "no environmental risks which could be linked to the development of a brain tumor" on the hospital's fifth floor, according to NWH. "Environmental risks" in this case were factors or conditions in the workplace that could cause harm to employees' health and safety. 

However, the Massachusetts Nurses Association (MNA), a union and professional association for nurses in the state, disputed the NWH investigation's findings, claiming in a statement sent via email that the hospital's testing was "not comprehensive." Instead, the union said it would carry out its own investigation into the cause of the diagnoses. The investigation was ongoing at the time of this writing.

Hospital and union dismissed claims that brain tumor diagnoses were linked to vaccines

The March 29 TPV article claimed that the diagnoses raised concerns about "a potential link between mRNA vaccines and cancer." The article did not specify how the website supposedly knew the vaccination status of the nurses, and the outlet did not elaborate when asked to comment.

Speaking about the rumor that the diagnoses were linked to the staff members being vaccinated against the SARS-CoV-2 virus, NWH said via email:

Regarding vaccines, NWH has completed a rigorous and comprehensive evaluation and has determined that the hospital environment is safe. The evaluation included testing for radiation as well as air and water testing.  The government has collected substantial data about Covid vaccines, and the vaccines are not associated with brain tumors. It's also important to note that some of the 5 diagnoses pre-date the pandemic.

We also asked the MNA about the vaccination claim. Joe Markman, the union's associate director of public communications, said:

The MNA represents 25,000 nurses in 85 facilities statewide. Almost all of our members were required to take the COVID-19 vaccine, but we are only experiencing this situation on the 5^th floor at NWH.

It is also worth noting that TPV's article claimed that 10 nurses were diagnosed with brain tumors, while NWH confirmed just five cases, all noncancerous.

Hospital investigation found no 'environmental risks'

According to the National Cancer Institute, the U.S. government's principal agency for cancer research, environmental exposures can damage DNA and cause cancer. Such exposures include "chemicals in tobacco smoke, or radiation, such as ultraviolet rays from the sun."

The NWH's investigation looked at environmental exposures, including radiation from X-ray machinery and chemotherapy drugs handled at the hospital's fourth floor pharmacy, to assess whether they could have caused the brain tumors.

The investigation also considered risks from wearing and reusing personal protective equipment like masks during the COVID-19 pandemic and found "no scientific evidence" linking the wearing of masks to brain tumors.

The investigation concluded that there were "no environmental risks which could be linked to the development of a brain tumor" at the hospital, according to a statement sent via email and attributed to Jonathan Sonis, NWH associate chief medical officer and vice president of medical affairs, and Sandy Muse, chief nursing officer and senior vice president of patient care services.

The statement from NWH read:

Every staff member who came forward was given the opportunity to be interviewed by the Occupational Health and Safety team to evaluate each diagnosis in the context of their individual medical history and risk factors. To evaluate for any possible environmental exposures in that area of the hospital, comprehensive environmental assessments following CDC guidelines began in December.

The investigation found no environmental risks which could be linked to the development of a brain tumor. We presented these findings to relevant stakeholder groups, including the staff on the unit and the Massachusetts Nursing Association, and have held forums to meet with clinical and Occupational Health leaders to answer their questions. The hospital provided the MNA with the test results from the investigation, including those of several external environmental firms.

The hospital's Q&A document, titled, "Fifth Floor Work Environment FAQs," further detailed the investigation. According to the document:

Through 4/1/2025, 11 staff members who have worked at some point and for varying durations on the Fifth Floor have been interviewed by the OHS.

• 6 cases were determined not to be brain tumors but rather other health concerns.
• 5 cases were determined to be brain tumors of 3 different types, all of which were benign (noncancerous).

The document said no further staff members had approached the hospital's occupational health service with diagnoses they thought could have resulted from working on the fifth floor.

Union claimed hospital provided 'predetermined conclusion'

The MNA, however, did not accept the results of the NWH investigation. In a statement sent via email, Joe Markman, the union's associate director of public communications, said the hospital was attempting to provide a "predetermined conclusion":

The hospital only spoke to a small number of nurses and their environmental testing was not comprehensive. The hospital cannot make this issue go away by attempting to provide a predetermined conclusion. While we currently cannot release specific numbers or other diagnosis information, we are committed to being transparent about our findings when we have finished verifying the information we collect. Completing this step-by-step process is critical to providing the support Newton-Wellesley nurses deserve.

The union heard from more than 300 current NWH nurses, former employees and other professional disciplines at NWH for its own investigation, Markman said, and was in the process of sorting through the information it had received.

In conclusion, the reasons behind the brain tumor diagnoses among staff at Newton-Wellesley Hospital's fifth floor maternity unit remain unclear. 

The hospital confirmed five brain tumor diagnoses in staff who worked "at some point and for varying durations" on the floor, with diagnoses dating back to before the COVID-19 pandemic in 2020. According to the hospital's investigation, there were no "environmental risks" linked to brain tumors present on the floor.