Tamoxifen treatment is an effective method for breast cancer prevention in women at high risk of developing the disease. Researchers from the Leeds Institute of Health Sciences surveyed at-risk women to understand their perception of tamoxifen treatment.
The International Breast Cancer Intervention Study published in 2015 demonstrated the effectiveness of tamoxifen treatment for breast cancer prevention. Tamoxifen treatment reduced the rate of new cases of breast cancer by one-third in women at risk of developing this disease. Despite these results, women with a high risk of developing breast cancer are reluctant to start tamoxifen treatment.
Many factors contribute to the decision to use tamoxifen treatment for breast cancer prevention. If physicians can identify these factors and address a patient’s concerns, a more personalized counselling approach may increase the rates of starting and continuing tamoxifen treatment.
A research team from the University of Leeds in the United Kingdom surveyed women at moderately high and high risk of developing breast cancer. Women were selected according to the National Institute for Health and Care Excellence criteria for breast cancer risk. The risk factors for developing this disease include age, weight, hormone replacement therapy, oral birth control use, alcohol consumption, and family history of breast cancer.
The at-risk women included in the study had previously discussed the option of preventative therapy with their doctors and had no known counterindications for tamoxifen use. The results of two questionnaires and a follow-up session will provide information about women’s perceptions of preventative therapy for breast cancer. The results of this study were published in the Clinical Breast Cancer Journal.
Study used questionnaires to assess patient concerns
Over 400 women with an increased risk of breast cancer were recruited in the study. Two surveys were distributed at the start of the study. The Beliefs About Medicine questionnaire is a four-part survey covering topics related to the patient’s perception about the necessity to be treated and the patient’s concerns about the drug. The last two sections concern the patient’s opinion about the general overuse of medication and the general harmful effects of treatment.
The Perceived Sensitivity to Medicines questionnaire gathers information regarding the patient’s thoughts about how their bodies react to medicine and a history of how their bodies have responded to medicine in the past. A follow-up was scheduled three months later to assess if women decided to take tamoxifen treatment.
Through statistical analysis of the data collected from the questionnaires, the researchers identified two distinct groups. One group consisted of women with a low perception of necessity for treatment and low concerns about the harmful effects of the drug. The second group consisted of women with a low perception of necessity for treatment but high concerns about the potential side effects.
The women classified in the high concerns group reported negative perceptions towards tamoxifen treatment and to medication in general. These women reported the highest sensitivities to medicines in the past and the highest concerns about medication overuse. At the three month follow-up, the women in this group were less likely to start tamoxifen treatment. In fact, at the three-month follow-up only 6.4% of women in the high concerns group started tamoxifen or received a prescription for tamoxifen.
Although women with low concerns about tamoxifen treatment were more likely to start the treatment, initiation rates were still meagre. Only 18.3% of women with low concerns started tamoxifen or received a prescription for tamoxifen at the three-month follow-up. The perception of the necessity for tamoxifen treatment for breast cancer prevention was low across both groups of women. Counselling strategies to improve initiation of preventative treatment require educating women on the effectiveness of tamoxifen and how it can address their personal needs.
Concerns over side effects of tamoxifen treatment and over-prescription
The most significant difference between the two groups of women in the study was the concerns about the side effects of tamoxifen treatment and the over-prescription of medication in general. The women with high concerns about side effects and overuse of medication not only require education on the necessity of treatment but also need support that helps resolve general concerns about medication. Tamoxifen is associated with many side effects; thus, the benefits and risks of the treatment must be communicated to all women with an increased risk of breast cancer. These strategies will help patients and their physicians make informed decisions.
The results of this study have identified several modifiable factors that can be targeted to improve initiation and adherence rates of tamoxifen treatment in women with an increased risk of breast cancer. Addressing a woman’s specific issues regarding the necessity and the dangers of tamoxifen treatment will allow them to make informed decisions about starting tamoxifen for breast cancer prevention.
Written by Jessica Caporuscio, PharmD
- Thorneloe RJ, Horne R, Side L; ENGAGE Investigators. Beliefs About Medication and Uptake of Preventive Therapy in Women at Increased Risk of Breast Cancer: Results From a Multicenter Prospective Study. Clin Breast Cancer. 2018.
- International Breast Cancer Intervention Studies. Barts CTU. 2017. URL: https://www.ibis-trials.org/thetrials/ibistrials/ibis-1
- National Institute for Health and Care Excellence. NICE. 2018. URL: https://www.nice.org.uk/guidance/cg164