The treatment strategy for early-stage HER2-positive breast cancer often involves a carefully sequenced combination of systemic therapies delivered before and after surgery. This approach, known as neoadjuvant and adjuvant therapy, is critical for achieving the best possible long-term outcomes and significantly reducing the risk of the cancer returning. Neoadjuvant therapy is administered before the operation with the aim of shrinking the tumor, making surgery easier, and allowing physicians to assess the tumor’s responsiveness to the drugs.

Achieving a pathological complete response (pCR)—meaning no residual invasive cancer cells are found in the breast or lymph nodes at the time of surgery—is a major goal of neoadjuvant treatment, as it is strongly associated with a higher probability of survival and cure. Current standard-of-care protocols for early-stage breast cancer often utilize chemotherapy combined with dual HER2-targeted agents like Trastuzumab and Pertuzumab in the neoadjuvant setting to maximize the pCR rate.

Following surgery, adjuvant therapy is administered to eliminate any remaining microscopic disease that may have escaped the pre-surgical treatment. This post-operative phase typically includes continued HER2-targeted therapy for a full year. For patients who have residual disease after neoadjuvant therapy, switching to a more potent Antibody-Drug Conjugate like Trastuzumab Emtansine (T-DM1) can significantly improve the disease-free survival rate, highlighting the importance of tailoring the adjuvant treatment based on the tumor’s response to the initial regimen.

FAQ

• What is neoadjuvant therapy? It is systemic treatment (like chemotherapy or targeted therapy) given before surgery to shrink the tumor, which can sometimes allow for breast-conseriving surgery and gives doctors prognostic information.

• How long does adjuvant treatment with Trastuzumab typically last? The standard duration for adjuvant Trastuzumab therapy is one year.