PURPOSE: Cancer treatments are complex, involving multiple clinicians, toxic therapies, and uncertain outcomes. Consequently, patients are vulnerable when breakdowns in care occur. This study explored cancer patients' perceptions of preventable, harmful events; the impact of these events; and interactions with clinicians after such events.

PATIENTS AND METHODS: In-depth telephone interviews were conducted with cancer patients from three clinical sites. Patients were eligible if they believed: something "went wrong" during their cancer care; the event could have been prevented; and the event caused, or could have caused, significant harm. Interviews focused on patients' perceptions of the event, its impact, and clinicians' responses to the event.

RESULTS: Ninety-three of 416 patients queried believed something had gone wrong in their care that was preventable and caused or could have caused harm. Seventy-eight patients completed interviews. Of those interviewed, 28% described a problem with medical care, such as a delay in diagnosis or treatment; 47% described a communication problem, including problems with information exchange or manner; and 24% described problems with both medical care and communication. Perceived harms included physical and emotional harm, disruption of life, effect on family members, damaged physician-patient relationship, and financial expense. Few clinicians initiated discussion of the problematic events. Most patients did not formally report their concerns.

CONCLUSION: Cancer patients who believe they experienced a preventable, harmful event during their cancer diagnosis or care often do not formally report their concerns. Systems are needed to encourage patients to report such events and to help physicians and health care systems respond effectively.