In 1982, the National Cancer Institute’s (NCI) Physician Data Query (PDQ) cancer information database went online. PDQ is a computerized database on cancer treatment information that became available nationwide via the U.S. National Library of Medicine’s MEDLARS system.

The PDQ health professional cancer information summaries are part of the comprehensive, evidence-based, up-to-date cancer content made available as a public service of the NCI. They are intended to: improve the overall quality of cancer care by informing and educating health professionals about the current published evidence related to individual cancer-related topics, and support informed decision making between clinicians and patients.