Appraisal of Systemic Treatment Strategies in Early HER2-Positive Breast Cancer—A Literature Review

SIMPLE SUMMARY: HER2-positive breast cancer (BC) is associated with an aggressive clinicopathological nature and is known to have a poor prognosis. Their tumor proliferation features can lead to visceral metastasis disseminating to the brain, liver, lung, and bone. Delivering standard chemotherapy HER2 blockers is strongly associated with better outcomes and can help increase the suitability for breast-conserving surgery. It is crucial to identify patients who should be selected for systemic cancer treatment before or after surgery and to decide the most appropriate option in each case. A thorough search and data collection were carried out using electronic scientific libraries and compiled with the most relevant and updated information about the stratification of BC recurrence risk and standard treatment options for each case. ABSTRACT: Background: The overexpression of the human epidermal growth factor receptor 2 (HER2+) accounts for 15–20% of all breast cancer phenotypes. Even after the completion of the standard combination of chemotherapy and trastuzumab, relapse events occur in approximately 15% of cases. The neoadjuvant approach has multiple benefits that include the potential to downgrade staging and convert previously unresectable tumors to operable tumors. In addition, achieving a pathologic complete response (pCR) following preoperative systemic treatment is prognostic of enhanced survival outcomes. Thus, optimal evaluation among the suitable strategies is crucial in deciding which patients should be selected for the neoadjuvant approach. Methods: A literature search was conducted in the Embase, Medline, and Cochrane electronic libraries. Conclusion: The evaluation of tumor and LN staging and, hence, stratifying BC recurrence risk are decisive factors in guiding clinicians to optimize treatment decisions between the neoadjuvant versus adjuvant approaches. For each individual case, it is important to consider the most likely postsurgical outcome, since, if the patient does not obtain pCR following neoadjuvant treatment, they are eligible for adjuvant T-DM1 in the case of residual disease. This review of HER2-positive female BC outlines suitable neoadjuvant and adjuvant systemic treatment strategies for guiding clinical decision making around the selection of an appropriate therapy.