Breast Cancer Survivorship Tool

Step 1: know your patient.

The BCS Tool highlights that breast cancer therapies can vary considerably from patient to patient, depending on the pathology of their tumours (Table 1).^8,9 The first step of providing appropriate breast cancer survivor care is understanding exactly which therapies the patient has received. Treatment side effects and monitoring requirements will vary widely based on the specific therapies.

The adjuvant therapy that a breast cancer patient receives depends on the risk of recurrence. Treatment might include chemotherapy, radiation therapy, and, if a patient’s tumour expresses the HER2 receptor (human epidermal growth factor receptor 2), she might also be offered the targeted therapy trastuzumab.

Endocrine therapy is offered to patients with tumours that are estrogen receptor–progesterone receptor positive. Estrogen blockade has been shown to decrease breast cancer mortality by about one-third throughout the first 15 years after definitive therapy.¹⁰ Postmenopausal women are offered endocrine therapy with aromatase inhibitors, which block peripheral conversion of androgens to estrogen. Although more effective than tamoxifen, aromatase inhibitors are contraindicated in premenopausal women, as lower peripheral levels of estrogen will induce the hypothalamus and pituitary gland to increase ovarian estrogen production.¹¹ Premenopausal or perimenopausal women can therefore take tamoxifen or, if they wish to obtain the added benefits conferred by therapy with an aromatase inhibitor, they must first achieve ovarian suppression via surgery or treatment with a gonadotropin-releasing hormone (GnRH) agonist. Tamoxifen, aromatase inhibitors, and GnRH agonists all have unique side effect profiles that require specific follow-up care.

Bisphosphonates have been found to be associated with a reduction in breast cancer recurrence in bone (rate ratio of 0.76) and in mortality (rate ratio of 0.82) in postmenopausal women.¹² Current guidelines suggest that postmenopausal women with intermediate- or high-risk cancers should receive zoledronic acid every 6 months for 3 years.¹³ Family physicians should interpret bone mineral density (BMD) measurements with the knowledge that their patients might have received, or are still receiving, bisphosphonates.

Step 2: cancer surveillance.

All breast cancer survivors should have follow-up visits with primary care providers every 6 months for the first 5 years after treatment completion. These appointments should include a thorough history, screening for signs and symptoms of local or distant recurrence, and treatment of side effects.^8,14 The BCS Tool highlights common sites of disease recurrence and associated symptoms, as well as common complications of therapy, which will help family physicians in their directed review of systems.

All breast cancer survivors should be screened for fatigue, depression, and anxiety, as one-third of ambulatory cancer patients report moderate to severe depressive symptoms, and fears around recurrence create considerable distress and anxiety.¹⁵ Clinical breast examinations should be done every 6 months, with specific attention paid to the regional lymph nodes, chest wall, lungs, and abdomen. Patients should be advised to perform monthly breast self-examinations.¹⁴ A diagnostic mammogram should be done annually.⁸ The cumulative effects of cancer therapy—chemotherapy, glucocorticoids (as antiemetics), and endocrine therapy—cause a degree of bone loss that is considerably greater than expected age-related bone loss.¹⁶ Baseline BMD measurement should therefore be performed for all postmenopausal women completing breast cancer therapy, as well as those patients with chemotherapy-induced premature menopause or those taking endocrine therapy with aromatase inhibitors or GnRH agonists.⁶ Patients who continue taking aromatase inhibitors are at increased risk of osteoporosis and should be screened on an ongoing basis with BMD measurement every 2 years,¹⁷ although clinical judgment should be employed to adjust the interval of BMD measurement depending on fracture risk. Lipid levels should also be monitored while patients are taking aromatase inhibitors, as these agents can cause hyperlipidemia.^14,18

Family physicians are in the unique circumstance of caring for patients as well as their extended families, and this position might allow for detection of familial cancer syndromes. Consider referring patients for genetic screening if criteria outlined in Box 1 are met.^19–22

Step 3: long-term side effects of treatment.

The BCS Tool highlights common long-term side effects from all treatments and appropriate management. Side effects might present immediately after therapy or might become apparent many years after completion of therapy. Regardless of the therapy received, breast cancer survivors are at a higher risk of cognitive dysfunction, fatigue, and psychological distress.^21–24 Breast cancer therapy can affect all spheres of life and might contribute to relationship issues, financial hardship, and ongoing anxiety around disease recurrence. Providers should be sensitive to psychological distress and should screen regularly and refer patients for counseling where appropriate.¹⁵ If pharmacotherapy is required, caution should be used if prescribing paroxetine or fluoxetine, as these agents might interact with tamoxifen, decreasing its efficacy.¹⁷

Lymphedema is the most common surgical complication; however, incidence has declined to 9% with sentinel node dissection compared with 40% with axillary dissection. Optimal management of lymphedema includes weight loss, compression sleeves, and massage therapy, with referral to a lymphedema specialist where available.²⁵

Patients taking tamoxifen have a relative increase in venous thromboembolic disease by a factor of 2 to 3, and have an increase in the relative risk of endometrial cancer of 2.7.¹⁷ Any vaginal bleeding in postmenopausal women taking tamoxifen must be investigated to rule out endometrial cancer. Aromatase inhibitors can cause considerable and often dose-limiting arthralgias and myalgias and increase the relative risk of osteoporotic fractures by 47%.^9,26

Cardiovascular health can be affected by all breast cancer therapies. The anthracycline chemotherapeutic agents epirubicin and doxorubicin might cause a decrease in ejection fraction, which can manifest as heart failure many years after completion of treatment.²⁷ Trastuzumab can also cause a decrease in heart function while taking the therapy, although this might be reversible if trastuzumab is discontinued.²⁸ Left-sided radiation can compound cardiotoxicity by causing fibrosis of any component of the heart, including valves, blood vessels, myocardium, and the conduction system.^29,30 Finally, aromatase inhibitors can contribute to the development of hypertension and hyperlipidemia.¹⁸ Ongoing surveillance of cardiac function in asymptomatic breast cancer survivors is currently not recommended¹⁶; however, primary care providers should view any symptoms of heart failure that might develop at any time after breast cancer treatment in the context of this therapy.

Step 4: health promotion.

Breast cancer survivors who are physically active, maintain a healthy weight, and avoid smoking and excessive alcohol use have a decreased risk of breast cancer recurrence.^31–33 Family doctors should actively engage with their patients who are breast cancer survivors to promote a healthy lifestyle.

With the myriad recommendations for breast cancer survivorship care, routine preventive health maneuvers can be overlooked. One Canadian study found that during a 4-year period, 65% of breast cancer survivors were never screened for colorectal cancer, and 40% were not screened for cervical cancer.³⁴ Primary care providers must ensure that survivorship care also includes appropriate preventive care.