Acceptability and Adherence in a Chemoprevention Trial among Women at Increased Risk for Breast Cancer Attending the Modena Familial Breast and Ovarian Cancer Center (Italy)

Abstract

Chemoprevention for women at risk for breast cancer has been shown to be effective, but in actual practice, women's uptake of chemoprevention has been poor. We explored factors that influence acceptability, adherence, and dropout in the International Breast (Prevention) Intervention Study during our first 3 years of activity at the Modena Familial Breast and Ovarian Cancer Center. We evaluated socio-demographic characteristics, health status, adherence, and side effect intensity. Semi-structured interviews analyzed reasons for accepting/refusing/stopping the trial. A total of 471 postmenopausal women were invited to participate, of which 319 declined to participate (68%), 137 accepted to participate (29%), and 15 participants did not make a final decision (3%). Breast cancer-related worries and trust in our preventive and surveillance programs were the most frequent reasons for accepting. Side effect-related worry was the most frequent reason for refusing. General practitioners' and family members' opinions played an important role in the decision-making process. Adherence significantly decreased after a 12-month follow-up, but it remained unchanged after 24- and 36-month follow-ups. Mild/moderate side effects reported by women did not change after 12 months of treatment. Forty percent of women withdrew from the study due to complaints of side effects. We concluded that chemoprevention trials are difficult medical experiments and that the process of deciding about whether or not to participate is based mainly on beliefs and values. This study has important clinical implications. During counselling with prospective participants, it is important to emphasize the potential benefits and to promote an informed choice. How participants make decisions, their belief systems, and their perception of risk are all factors that should be investigated in future research.

Participant-Reported Symptoms and Their Effect on Long-Term Adherence in the International Breast Cancer Intervention Study I (IBIS I)

“…9 However, the design of these studies was subject to bias because of retrospective recall when completing the off-therapy forms and an inability to compare adherence rates between those who did and did not experience adverse effects. 20-23 Data from the NSABP P-1 trial has demonstrated the role of gynecologic, vasomotor, and sexual symptoms on adherence at 1-year follow-up. 17 Our analysis adds to these data by demonstrating that more than one fifth of 5-year nonadherence can be explained by participant-reported early symptoms.…”

“…9 Studies that collected off-therapy forms report that more than half of all women who drop out of preventive therapy trials attribute their decision to adverse effects of medication. 20-23 However, retrospectively assessing decisions to discontinue medications may be a biased approach.…”

The PARP Inhibitors, Veliparib and Olaparib, Are Effective Chemopreventive Agents for Delaying Mammary Tumor Development in BRCA1-deficient Mice

“…For these reasons, intermittent therapy with PARP inhibitors could be a viable approach for chemoprevention and its potential benefits, if translated into clinical practice, could be marked for high-risk patients with BRCA1 mutations. Moreover, intermittent dosing could also potentially circumvent one of the major challenges in chemoprevention regimens, namely poor adherence because of cost, unfavorable side effects and the duration of drug exposure (61, 62). …”

The impact of reproductive life on breast cancer risk in women with family history or BRCA mutation

“…Nonetheless, an accurate risk assessment in these high-risk populations remains fundamental, in order to establish personalized strategies for risk control (i.e. surveillance, chemoprevention [15] and prophylactic surgery [16]). At this aim, reproductive factors were investigated in a population of Italian women attending the Modena Family Cancer Clinic (MFCC), comparing women classified at different levels of increased BC risk.…”