What is the significance of a Tyrer-Cuzick (Tyrer-Cuzick model, a breast cancer risk assessment tool) lifetime risk of 37.7%, indicating an elevated risk of developing breast cancer?

From the Guidelines

A Tyrer-Cuzick lifetime risk of 37.7% indicates a high risk for developing breast cancer, significantly above the average population risk of approximately 12-13%, and warrants referral to a high-risk breast clinic or genetic counselor for comprehensive management. Consider genetic testing for BRCA1/2 and other breast cancer susceptibility genes, as your risk level suggests possible hereditary factors 1. Enhanced surveillance is recommended, including annual mammograms starting at age 30 (or 10 years before the earliest breast cancer in your family), annual breast MRI, and clinical breast exams every 6-12 months. Risk-reducing medications like tamoxifen, raloxifene, or aromatase inhibitors should be discussed as they can lower your risk by 40-50% 1. Lifestyle modifications are also important:

• maintain a healthy weight
• limit alcohol consumption
• exercise regularly
• avoid hormone replacement therapy when possible Risk-reducing mastectomy might be an option to consider if you have additional risk factors or significant anxiety about developing breast cancer. This comprehensive approach is warranted because your 37.7% lifetime risk is approximately three times higher than average, placing you in a category where more aggressive prevention and early detection strategies can significantly improve outcomes. According to the American Society of Clinical Oncology, women with a strong family history of breast cancer, such as those with a Tyrer-Cuzick lifetime risk of 37.7%, should be referred to special clinics for cancer risk education, counseling, genetic testing, and breast cancer risk reduction recommendations 1.

From the Research

Tyrer-Cuzick Lifetime Risk of 37.7%

• A Tyrer-Cuzick lifetime risk of 37.7% indicates a high risk of developing breast cancer.
• According to the studies, several medications can reduce the risk of breast cancer, including tamoxifen and raloxifene 2, 3, 4, 5, 6.
• The Study of Tamoxifen and Raloxifene (STAR) demonstrated that raloxifene was as effective as tamoxifen in reducing the risk of invasive breast cancer in postmenopausal women 2, 6.
• The benefits and risks of tamoxifen and raloxifene depend on age, race, breast cancer risk, and history of hysterectomy 2.
• A systematic review found that tamoxifen, raloxifene, and tibolone reduce the risk of invasive breast cancer, but increase the risk of thromboembolic events, endometrial cancer, and stroke 4.
• The use of raloxifene and tamoxifen for breast cancer risk reduction is low, but increases with breast cancer risk level 5.
• The NSABP Study of Tamoxifen and Raloxifene (STAR) P-2 trial found that raloxifene is as effective as tamoxifen in reducing the risk of invasive breast cancer, with a lower risk of thromboembolic events and cataracts, but a nonstatistically significant higher risk of noninvasive breast cancer 6.

Medication Options

• Tamoxifen: reduces the risk of invasive breast cancer, but increases the risk of thromboembolic events, endometrial cancer, and cataracts 2, 3, 4, 6.
• Raloxifene: reduces the risk of invasive breast cancer, with a lower risk of thromboembolic events and cataracts, but a nonstatistically significant higher risk of noninvasive breast cancer 2, 3, 4, 6.
• Tibolone: reduces the risk of invasive breast cancer, but increases the risk of stroke 4.

Considerations

• The decision to use tamoxifen or raloxifene for breast cancer risk reduction should be based on individual risk factors and medical history 2, 5.
• The benefits and risks of these medications should be carefully weighed, and patients should be closely monitored for potential side effects 2, 4, 6.