How would a latent period for early breast cancer affect the benefit of screening?

Abstract

The ideal goal of a screening program for breast cancer is to detect the disease at a stage when it is still curable by a simple lumpectomy. This goal would be possible if the tumor had an early latent period before it was vascularized. However, even if there existed a harmless screening examination that was sensitive enough to discover the cancer at this stage the benefit to be gained from a screening program would be highly dependent on the time the tumor spends in the latent stage as well as on the chance of false negatives at the examination. Calculations derived from a mathematical model suggest a variety of theoretically possible situations including: (1) For certain cancers screening every three years would offer almost as much benefit as screening every year; (2) A large increase in the sensitivity of a screening examination does not necessarily lead to a large increase in the benefit of a screening program; (3) For certain cancers the benefit of screening might remain low no matter how sensitive the examination used.