DOI: 10.5061/dryad.q83bk3jmc
title: Feasibility and acceptability of personalized breast cancer screening (DECIDO Study): A single-arm proof-of-concept trial

description: The aim of this study was to assess the acceptability and feasibility of
 offering risk-based breast cancer screening and its integration into
 regular clinical practice. A single-arm proof-of-concept trial was
 conducted with a sample of 387 women aged 40–50 years residing in the city
 of Lleida (Spain). The study intervention consisted of breast cancer risk
 estimation, risk communication and screening recommendations, and a
 follow-up. A polygenic risk score with 83 single nucleotide polymorphisms
 was used to update the Breast Cancer Surveillance Consortium risk model
 and estimate the 5-year absolute risk of breast cancer. The women
 expressed a positive attitude towards varying the frequency of breast
 screening according to individual risk and, especially, more frequently
 inviting women at higher-than-average risk. A lower intensity screening
 for women at lower risk was not as welcome, although half of the
 participants would accept it. Knowledge of the benefits and harms of
 breast screening was low, especially with regard to false positives and
 overdiagnosis. The women expressed a high understanding of individual risk
 and screening recommendations. The participants’ intention to participate
 in risk-based screening and satisfaction at 1-year were very high.
description: From January 2019 to February 2021, 387 women aged 40 to 50 years
 were enrolled in the study. Potential participants were the 2038 women
 living in the “Primer de Maig” Basic Health Area in Lleida, Catalonia, on
 31 December 2018, who would have turned between 40 to 50 years of age
 during the following 1.5 years. Accrual was suspended because of the
 COVID-19 pandemic in March 2020 when 252 women had been included and
 resumed in October 2020. All women who turned 50 during
 the study period would have received the first invitation to participate
 in the population-based Breast Cancer Early Detection Program. Instead,
 they were invited to participate in our study. Women that declined were
 invited by the early detection program. From women that turned 40 to 49
 years during the study period, random samples of 20 to 50 women were
 selected from the potential participants on a monthly basis, and the women
 were invited to participate until the accrual goal was achieved.
 Exclusion criteria included having a previous diagnosis of breast
 cancer, undergoing a current breast study, or fulfilling clinical criteria
 for cancer-related genetic counseling. We also excluded women not
 understanding or speaking Catalan or Spanish or those with a physical or
 cognitive disability that prevented breast screening or the main outcome’s
 assessment. The study intervention consisted of a
 baseline visit, the breast cancer risk estimation, a visit for risk
 communication and screening recommendations, the administration of a
 follow-up questionnaire, and a phone call to assess satisfaction after one
 year. The baseline visit was held at the Primary Care
 center, where the healthcare professional provided information about the
 study objectives; facilitated an informative brochure about the benefits
 and adverse effects of breast cancer screening; obtained information on
 sociodemographic variables, risk factors, previous screening experience,
 perceived personal risk of breast cancer, and general screening knowledge,
 attitudes, and intentions; obtained a saliva sample to determine the
 genomic profile; and scheduled a screening mammogram with breast density
 measurement. For women that had a mammogram during the year before the
 first visit, breast density and presence/absence of benign lesions were
 obtained from that mammogram and the radiologist’s report.
 Breast density was classified according to the Breast Imaging
 Reporting and Data System (BI-RADS), 5th edition, scoring system: almost
 entirely fatty (a), scattered areas of fibroglandular density (b),
 heterogeneously dense (c), and extremely dense (d). Mammographic findings
 were coded from 0 (incomplete—additional imaging needed) to 6 (known
 biopsy—proven malignancy). In the case of abnormal results, additional
 tests were requested. Collection, conservation, and
 delivery of saliva samples was completed following the saliva collection
 protocol provided by the University of Lleida’s Proteomics and Genomics
 Service. Details about the genotyping process can be found in the
 protocol. The PRS was obtained using the 83 SNPs associated with breast
 cancer, based on Shieh et al.’s or Mavaddat et al.’s studies, as a
 composite likelihood ratio representing the individual effects of each
 SNP. The primary outcome measures were attitude
 towards, intention to participate in, and satisfaction with personalized
 breast cancer screening by participating women. Attitude was measured with
 a three-item scale, each item ranging from 1 to 5, with higher scores
 indicating more positive attitudes. A “positive attitude” was defined as a
 total score greater than or equal to 12. Intention to participate was
 measured with a 5-point Likert scale from definitely will (1) to
 definitely will not (5). The variable was also dichotomized as intending
 to participate (definitely or likely) or not. Satisfaction was assessed
 after one year of recruitment and was measured on a 5-point Likert scale
 from very unsatisfied (1) to very satisfied (5). Secondary outcomes (e.g.,
 attitude towards screening mammography, attitude towards measuring breast
 cancer risk, emotional impact of the measure of breast cancer risk,
 preference with regard to the current screening, knowledge, decisional
 conflict, confidence, and participation) have been detailed in full in the
 study protocol. The R programming language and the
 RStudio environment were used for the data analysis. The Likert function
 of the HH package was used to obtain the graphical representation of the
 primary outcomes measured as Likert scales.
description: The R programming language and the RStudio environment.