Duarte, Calif.-based City of Hope reported a data breach affecting hundreds of thousands of patients last year.
The cancer care network identified suspicious activity on a subset of its systems Oct. 13 and took action to minimize the disruption to operations. City of Hope then investigated the scope of the incident and worked with a cybersecurity firm to assess the incident.
An unauthorized party accessed City of Hope's systems and copied files, including some that contained personal information, according to an April 2 statement. The personal information included names, Social Security numbers, financial details, health insurance information and medical records.
The incident potentially affected 827,149 patients' information, according to a data breach notification filed with the Main Attorney General's office. City of Hope has implemented additional safeguards to prevent further attacks.
City of Hope has locations in California, Arizona, Illinois and Georgia where more than 11,000 clinicians, researchers and professionals provide patient care.