(ChemotherapyAdvisor) – A model designed to determine the effect of prostate cancer screening on quality of life has found that although life years would be gained, the harms of overdiagnosis and treatment from such screening would result in fewer quality-adjusted life-years (QALYs), a study reported in the August 16 issue of the New England Journal of Medicine.
“After 11 years of follow-up, the European Randomized Study of Screening for Prostate Cancer (ERSPC) reported a 29% reduction in prostate-cancer mortality among men who underwent screening for prostate-specific antigen (PSA) levels,” Eveline A.M. Heijnsdijk, PhD, Erasmus Medical Center, Rotterdam, the Netherlands, and colleagues noted. “However, the extent to which harms to quality of life resulting from overdiagnosis and treatment counterbalance this benefit is uncertain.”
Using Microsimulation Screening Analysis, they predicted the number of prostate cancers, treatments, deaths, and QALYs gained after PSA screening and modeled various screening strategies, efficacies, and quality-of-life assumptions.
“Per 1,000 men of all ages who were followed for their entire life span, we predicted that annual screening of men between the ages of 55 and 69 years would result in 9 fewer deaths from prostate cancer (28% reduction), 14 fewer men receiving palliative therapy (35% reduction), and a total of 73 life-years gained (average, 8.4 years per prostate-cancer death avoided),” the investigators reported.
A total of 56 QALYs (range, −21 to 97) were gained, or a reduction of 23% from unadjusted life-years gained. “To prevent one prostate-cancer death, 98 men would need to be screened and 5 cancers would need to be detected. Screening of all men between the ages of 55 and 74 would result in more life-years gained (82) but the same number of QALYs (56).” Overdiagnosis and overtreatment of 45 cases and loss of 1,134 life-years free of prostate cancer would be the harms caused by PSA screening.
“It is essential to await longer follow-up data from the ERSPC, as well as longer-term data on how treatment and active surveillance affect long-term quality of life, before more general recommendations can be made regarding mass PSA screening,” they concluded.
An accompanying editorial notes: “This study has two important implications. It reminds us in stark terms that decisions about PSA screening depend in part on how the patient feels about the downstream consequences of screening, a fact that is easily forgotten in the stress of daily office practice. More important, however, the study is a model for developing the evidence base for practice guidelines…In the future, a decision-support system incorporating the authors’ model could provide patients with individualized assistance with the decision regarding PSA screening.”