Novocure Data Breach Affects More Than 1,400 Cancer Patients

The Novocure data breach exposed records connected to more than 1,400 cancer patients in the United States after attackers accessed parts of the company’s systems in mid-August.

Novocure said most affected patient records contained identification numbers but no names or other direct personal details. The company also found that attackers accessed employee contact information.

Attackers accessed patient and employee information

Novocure, an oncology company known for its Tumor Treating Fields therapy, discovered unauthorised access to some information systems during the middle of August.

Its investigation found that attackers accessed records for more than 1,400 US patients. Those records included patient ID numbers, but Novocure said they did not contain names or other identifying information.

For fewer than 50 patients in the western United States, attackers also accessed identifying details and general contact information for healthcare providers.

The Novocure data breach additionally exposed contact details for an undisclosed number of employees. The information included job titles and phone numbers.

Cancer treatment devices remain unaffected

Novocure said the incident did not affect any of its medical treatment devices. The company added that its operations continue as normal and that all systems remain functional.

The company is reviewing its legal and regulatory notification duties. It said it will notify affected patients and other parties where required.

Novocure has not disclosed how attackers gained access to its network. It also has not said whether the attackers demanded a ransom.

Healthcare sector faces continuing cyberattacks

The Novocure data breach follows several recent security incidents across the healthcare sector.

Healthcare software company Unlimited Technology Systems recently reported that an October 2025 breach affected more than 3.8 million people. CareCloud also said that a March breach impacted more than 3.7 million individuals.

Meanwhile, Nutex is investigating data theft from company servers, while McKesson disclosed a cybersecurity incident after the ShinyHunters group claimed it stole hundreds of millions of patient records.