**5. Pharmacological interventions**

#### **5.1. Adjuvant chemotherapy for breast cancer management**

Some patients with early breast cancer relapse with stage IV breast cancer even after surgery, reason may be the presence of micrometastatic disease present before the surgery [2]. For this reason in breast cancer patients adjuvant systemic therapy are used to halt the process of cancer recurrence [2]. It has been shown and proved by several trials that 6 months anthracycline therapy following surgical treatment of cancer results in about 40% reduction in mortality rates from breast cancer in women below age of 50 years and 20% reduction in between 56 and 69 age group [2, 41]. Further analysis showed that the addition of taxane based chemotherapy to anthracycline based regimen reduced mortality rate by further 15% [2, 41].

#### **5.2. Adjuvant trastuzumab monoclonal antibody**

At least 18–20% of breast cancer patients tumor cells overexpress HER-2 proteins [42]. In these patients trastuzumab (monoclonal antibody) is given as an adjuvant therapy [2, 42]. Full course of 52 treatments are given to woman with breast cancer [42]. Trastuzumab is well tolerated at therapeutic doses but may result in cardiac toxicity in patients initially given anthracycline regimen or in patients having baseline cardiac problem [43]. Left ventricular dysfunction and heart failure is reported in some patients by administration of trastuzumab [42]. All breast cancer patients should have scheduled cardiac monitoring before and during administration of therapy [2, 42].

#### **5.3. Adjuvant endocrine therapy and breast cancer management**

The majority of breast cancers are estrogen receptor (ER) positive [2, 42]. In those women with ER positive breast cancer, adjuvant endocrine therapy is routinely offered [2, 42]. The addition of endocrine therapy following either adjuvant chemotherapy or radiotherapy confers a further reduction in mortality rates [2, 42]. Tamoxifen is the mainstay of endocrine treatment in premenopausal woman [2, 42]. In post-menopausal woman aromatase inhibitors are the agents of choice [2, 42].
