Background and Importance The new anti-HER2 conjugated drugs have represented a significant advancement in the treatment and management of metastatic HER2-positive breast cancer patients, enabling the application of local ablative therapy in the case of oligoprogression, with a positive impact on the survival of these patients.

Aim and Objectives The objective of this text is to provide a comprehensive overview of the patient‘s medical history and treatment progression in managing HER2-positive breast carcinoma. It aims to underscore the importance of pharmaceutical interventions, interdisciplinary cooperation, and adaptability in achieving favourable treatment outcomes for patients with complex oncological conditions.

Material and Methods 51-year-old woman. Diagnosed in May 2005 with infiltrating ductal carcinoma of the left breast, underwent surgery after neoadjuvant chemotherapy + Trastuzumab, luminal B HER2-positive immunophenotype. Subsequently, received adjuvant radiotherapy + trastuzumab + hormone therapy. All treatments concluded in April 2011.

Results In January 2020, she was admitted to the Internal Medicine ward due to dyspnea related to bilateral paraneoplastic pulmonary embolism, prompting an extension study revealing multiple metastatic bone lesions. Bone biopsy confirmed infiltration by HER2-positive breast carcinoma. In February 2020, she commenced first-line systemic treatment with Docetaxel + Trastuzumab + Pertuzumab, with excellent tolerance.

In December 2021, disease progression was observed with the emergence of lung metastases and a pre-sternal nodule, while bone disease remained stable. A request was made to Pharmacy for Trastuzumab-Emtansine treatment, which commenced in January 2022.

In May 2023, there was growth of the pre-sternal lesion while other lesions remained stable. After histologically confirming the same immunophenotype, the case was discussed in a multidisciplinary committee, and it was decided to administer stereotactic body radiation therapy (SBRT) while maintaining systemic treatment for proper local control. The patient continues treatment with a good clinical course.

Conclusion and Relevance This pharmaceutical perspective highlights the patient‘s treatment journey and the role of various therapies in managing HER2-positive breast carcinoma, emphasising the need for adaptability and interdisciplinary collaboration to optimise outcomes.

Conflict of Interest No conflict of interest.