Complete Response of Chemo-Refractory Metastatic Metaplastic Breast Cancer to Paclitaxel-Immunotherapy Combination

Patient: Female, 49 Final Diagnosis: Metastatic metaplastic breast cancer Symptoms: Progressive right breast mass Medication: 5-fluorouracil • Cytoxan • Epirubicin (FEC 100) • Docetaxel • Capecitabine Clinical Procedure: Mastectomy • Radiation Therapy Specialty: Oncology OBJECTIVE: Rare disease BACKGROUND: Metaplastic breast cancer (MPBC) is a rare subtype of breast cancer that is difficult to manage and is resistant to therapy. Immunotherapy is becoming a promising option for care of several types of cancers including triple negative breast cancer. CASE REPORT: We present a case of a patient with chemo-refractory metastatic metaplastic-type of breast cancer with failures to 3 active lines of chemotherapy. The patient achieved a complete and sustained response to chemo-immunotherapy combination with acceptable tolerability and minimal adverse events. The treatment was a combination of anti-PD-L1 antibody (durvalumab) immunotherapy in combination with the chemotherapeutic agent, paclitaxel. CONCLUSIONS: This is the first case reporting the successful use of durvalumab and paclitaxel combination for treatment of triple negative breast cancer in general, and in metastatic MPBC in specific.