Grant Details
Grant Number: |
5R01CA267725-02 Interpret this number |
Primary Investigator: |
Sawaya, George |
Organization: |
University Of California, San Francisco |
Project Title: |
Cervical Cancer Screening After Age 65 in the Era of HPV Testing: Estimating Benefits and Harms of Screening Cessation and Continuation |
Fiscal Year: |
2023 |
Abstract
Project Summary
Cervical cancer screening represents a remarkable success story that has led to profound reductions in cancer
incidence and mortality in the United States (US), yet fundamental questions about screening cessation
remain. For the last 25 years, the US Preventive Services Task Force (USPSTF) has recommended screening
cessation at age 65 in those deemed to have been adequately screened. The increase in life expectancy over the
last 25 years, however, raises questions about whether healthy, well-screened women over age 65 should
continue screening. In fact, an estimated 21% of cervical cancer cases and 35% of deaths in the US occur after
age 65. Screening older people for cancer, however, involves a judicious consideration of the balance between
benefits and harms. For example, cervical cancer prevention through screening is only achieved by performing
surgical procedures on the cervix, including hysterectomies, which may pose a higher risk of major medical
complications for older women. Because up to 60% of women have not met the criteria to end screening at age
65, an estimated 1,700,000 women turning age 65 each year in the US can be expected to continue screening.
In its most recent guideline, the USPSTF stated that research is needed to elucidate the balance of benefits and
harms in various groups of women over age 65. The aims of this proposal will fill significant evidence gaps
concerning the benefits and harms of cervical cancer screening after age 65. Aim 1 will involve a cohort study
of about 280,000 women over 65 who were long-term members of two large health systems during 2005-2022
to investigate cervical cancer incidence, stage at cancer diagnosis, and cancer mortality by screening history
documented ages 55 to 65. We will also use causal inference methods to emulate a randomized trial using
observational data to estimate the effectiveness of screening after age 65 on cancer outcomes. Aim 2 involves a
cohort study of women screened after age 65 to investigate harms, including the incidence and predictors of
medical complications resulting from diagnostic procedures and surgical interventions. We will also conduct
qualitative interviews in a sample of women to evaluate the personal experiences of women who continue with
the screening process after age 65. Aim 3 will involve the enumeration of actual screening outcomes of 33,000
women screened after age 65 to inform a decision analytic model that will estimate benefits and harms of
screening continuation after age 65 compared with screening cessation. We have assembled an ideal study
team with expertise in obstetrics/gynecology, infectious disease, cancer epidemiology, cancer screening
decision modeling, biostatistics, and geriatrics. Completion of this proposal’s aims will fill important gaps and
move the field forward by providing evidence to make cervical cancer screening guidelines that better balance
benefits and harms in older women.
Publications
None