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Intermediate Technical IVT

adverse event

Also written as: AE — Adverse Event

Unfavorable medical occurrence in a cancer patient during treatment, requiring systematic documentation and severity grading for safety monitoring.

Full Definition

An adverse event (AE) in oncology refers to any unfavorable or unintended medical occurrence experienced by a patient during cancer treatment, regardless of whether it is considered related to the therapy. Adverse events encompass a broad spectrum of medical problems, from mild side effects to life-threatening complications, and must be systematically documented, graded for severity, and assessed for relationship to treatment. The Common Terminology Criteria for Adverse Events (CTCAE) provides standardized grading scales from 1 (mild) to 5 (death) for consistent reporting. Proper adverse event documentation is crucial for patient safety monitoring, regulatory compliance, and the ongoing assessment of treatment benefit-risk profiles in both clinical practice and research settings.

Usage

Usage note: Use 'adverse event' rather than 'adverse drug reaction' unless specifically referring to drug-related events; always grade severity when reporting.

In Context

  • "The patient experienced grade 3 neutropenia as an adverse event following chemotherapy." — Clinical progress note
  • "Adverse event reporting must follow institutional and regulatory timelines for serious events." — Clinical trial protocol

Also known as

AE adverse drug reaction treatment-related toxicity

Contrasted with

expected outcome therapeutic response

Don't confuse with

side effect complication serious adverse event

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