Addressing Long Term Side EffEcts

All breast cancer survivors should be screened for late-term side effects including fatigue, lymphedema, depression, and anxiety. The following table presents the potential of late side effects and recommended treatment for breast cancer. Your patient may present with some of the complications outlined below.

Complication

Recommended Treatment

Fatigue

This is could be due to radiation and/or chemotherapy. Fatigue should start to improve within months of treatment completion. Persistent or recurrent fatigue warrants further work-up to rule out other potential causes like anemia or thyroid. For further information please refer to the Cancer-Related Fatigue Guideline.

Peripheral neuropathy

These side effects are mainly due to chemotherapy. Peripheral neuropathy should improve over months. Painful paresthesias may respond to gabapentin or amitriptyline. If neuropathy is progressive/persistent consider additional investigations and referral to neurology.

Lymphedema

Early symptoms include arm heaviness or discomfort and may be present with/without overt swelling. Referral to local rehabilitation therapy services (e.g. physiotherapy) or tertiary lymphedema clinic can be made.

Menopausal Symptoms

Endocrine therapies commonly cause menopausal symptoms and chemotherapy may lead to early menopause. These symptoms include hot flashes, arthralgias, and vaginal dryness.

Treatment includes non-hormone therapies (e.g. venlafaxine or gabapentin). Vaginal dryness can be managed with a dual purpose non-hormonal vaginal moisturizer and lubricant (e.g. Replens®).

Oral estrogens (such as hormone replacement therapy) are not recommended in patients with a prior history of breast cancer due to concern for increasing breast cancer recurrence. However topical estrogen can be a reasonable option for certain survivors.

Sexual Health

All breast cancer survivors should be screened for any sexual issues. Survivors can be referred to a gynaecologist or sex therapist.

Specific Concerns for Breast Cancer Patients

Endocrine Therapy:

For patients with ER+ breast cancer who have been initiated on adjuvant endocrine therapy (e.g. either single agent or sequential agent – tamoxifen and/or an aromatase inhibitor), encourage endocrine therapy adherence and assess for side effects and complications.

Once the patient is transferred from the cancer centre back to your care you may write refill prescriptions for these medications. Typically, endocrine therapy is prescribed for five years in total – however, selected patients may be offered an extended duration of therapy beyond five years. If you and/or your patient have any questions in this regard, please contact your patient’s medical oncologist for additional clarification.

Potential side effects or complications of endocrine therapy:

Tamoxifen

Commonly causes hot flashes and (non-bloody) vaginal discharge. It increases the risk for rare complications such as venous thrombotic events, endometrial cancer, cataracts, and possibly stroke.
Patients with persistent, abnormal vaginal bleeding should be referred to a gynecologist for further evaluation given the theoretical risk of endometrial cancer. Endometrial ultrasound and endometrial biopsy should be performed if this case. Stop Tamoxifen, refer to gynecology and consult a medical oncologist for direction. Routine surveillance ultrasounds in asymptomatic individuals are discouraged.

Aromatase inhibitors (e.g. anastrozole, letrozole, exemestane)

Commonly cause hot flashes, arthralgias, and vaginal dryness. These drugs also increase the risk of osteopenia and/or osteoporosis. Patients currently taking aromatase inhibitors should be monitored with a baseline and regular bone density assessment and treated and monitored according to current Canadian Osteoporosis Guidelines (osteoporosis.ca). EVISTA® (raloxifene) should NOT be prescribed for the management of osteopenia/osteoporosis.

Bisphosphonate Therapy:

Some postmenopausal patients may be prescribed bisphosphonate therapy (clodronate 1600 mg po daily or zoledronic acid 4 mg IV every 6 months) for 2 to 5 years as part of their breast cancer treatment. Clodronate prescriptions need to be filled at a community pharmacy. Patients on adjuvant zoledronic acid will have appropriate lab monitoring and will be treated at the cancer centre. Given the small risk for osteonecrosis of the jaw, we counsel patients to inform their dentist of bisphosphonate therapy use prior to procedures and to see their dentist in the event of persistent mouth ulcer, or tooth or jaw pain.

The exact endocrine and bisphosphonate therapy regimen will be decided in consultation with your patient and communicated to your patient and yourself by your patient’s medical oncologist.