CU Cancer Center

What Are Pack-Years?

Written by Rachel Sauer | January 03, 2023

For many people, receiving a cancer diagnosis may require learning a new vocabulary ­– terms that can be useful guideposts for defining the disease and its treatment.

People diagnosed with lung cancer who currently smoke or have a history of smoking, for example, may have heard the term “pack-year” when they consulted with clinicians to determine whether they should be screened for the disease.

Jamie L. Studts, PhD, co-leader of the University of Colorado Cancer Center Cancer Prevention and Control Program, defines this often-used term and answers some common questions related to its use.