Cancer Risk Assessment

The role of hormonal therapy for risk reduction should be carefully considered and discussed with experts in breast cancer risk assessment and management in a shared decision-making environment. Guidelines from expert groups recommend that the risks and benefits of breast cancer prevention be discussed with premenopausal and postmenopausal women who are at high risk for the disease.

Women at high risk may include some women over the age of 60; women with certain high-risk conditions found on breast biopsy, such as lobular carcinoma in situ (LCIS) or atypical ductal or lobular hyperplasia; women between the ages of 35 and 59 years who have a calculated five-year risk of developing breast cancer of 1.7 percent or higher, according to a system called the Gail model. The Gail model uses a woman's current age, age at first menstrual period, age at first live birth, the number of first-degree relatives with breast cancer, and the number and pathologic findings of any breast biopsies to estimate the probability of breast cancer over time. This model, and others, is used by health professionals to calculate an individual’s risk and the results should be interpreted with an expert in breast cancer risk assessment. It is also important to remember that the presence of breast cancer risk factors does not mean that cancer is inevitable as many women with risk factors never develop breast cancer.

Another very important issue is that the Gail model does not consider the risk of cancer associated with inherited breast cancer-predisposing genes such as BRCA1 and BRCA2. If an individual has a strong family history that suggests the possibility of an inherited predisposition to breast cancer, then that individual should be referred for genetic counseling. Other components of a risk/benefit assessment and counseling include a careful discussion of the side effects of hormonal therapy, options for participation in clinical research and healthy lifestyle changes.

Americans get risk screening all the time but we generally don't think of these tests in those terms. Assessment of cholesterol levels in the blood and blood pressure are risk assessments for heart disease and stroke. These are offered to essentially everyone and help to direct additional testing (advanced cardiac/vascular examinations) and treatment (cholesterol and blood pressure lowering medicines). There is no downside to risk assessment in all women and can help direct advanced breast imaging and closer follow ups as well as alleviating fear in some women who overestimate their risk of developing breast cancer. The risk assessment requires no blood draws and can be done in less than 5 minutes by a trained medical assistant.

Tyrer-Cusick breast cancer risk assessment was developed in the UK by PhD's and is the most comprehensive risk assessment tool currently available. The model takes into account the person's history (age, extended family history of breast and ovarian cancer, child birth history, history of breast biopsy and it's pathology, age of menarche and menopause, exposure to post menopausal hormones, Ashkenazi Jewish heritage) as well as their height/weight (higher BMI-body mass index=increased risk). After taking all the various factors into consideration a curve is generated representing the person's lifetime risk compared to 'standard risk' and also the chance of having both a BRCA 1 and BRCA 2 genetic mutation.

The Gail model was developed in the 1980's by a US physician and combines some history (first generation relatives with breast cancer, age of menarche and menopause, number of breast biopsies, atypia in a biopsy) and age to calculate 5 year and lifetime risks of developing breast cancer. A Gail Model risk of 1.7% at 5 years was used as entry criteria for both of the NSABP breast cancer prevention trials.

Great question. Not many. Most ovarian cancer just happens because of bad luck. Less than 25% of ovarian cancer is caused by an inherited identifiable genetic mutation. Certainly a patient with a family history of ovarian cancer should be evaluated to determine if she qualifies for BRCA testing. This can be done either by a formally-trained genetic counselor or by less-formally-trained healthcare providers who have been educated about risk assessment for various cancers including ovarian cancer. Ovarian cancer happens to about 1% of women with no risk factors. If a first degree relative has ovarian cancer, the risk goes up to 4%. If the patient has a BRCA mutation, the risk can be as high as 44%. With Lynch syndrome, a combination of uterine, colon, ovarian, and a few other cancers, the risk is between 10-15%. Women who have never had a baby, who had early menarche and late menopause, and who have never taken the pill are at slightly higher risk given that there ovaries never took a break from ovulating. There is controversy over whether "super ovulation" (using medications to increase the number of eggs ovulated) used in infertility patients increases the risk of ovarian cancer. Patients with any of these factors are evaluated regularly and advised to report any changes in bowel or bladder habits or pelvic symptoms that might be associated with ovarian cancer (see prior question).