What happened, in summary

A 45-year-old woman was diagnosed with Stage III invasive ductal breast cancer that was ER-negative, PR-negative and HER2-positive. She began neoadjuvant docetaxel, carboplatin and trastuzumab. The tumor responded, but after the sixth cycle she developed profound anemia that did not improve with erythropoietin and required repeated blood transfusions. She then underwent a right modified radical mastectomy, and the surgical pathology showed a complete response with no remaining breast cancer. Persistent anemia led to bone-marrow testing and a diagnosis of acquired pure red cell aplasia, a rare condition in which red-cell production is severely reduced. The anemia improved after treatment with cyclosporine. Once her blood counts recovered, she completed 25 radiation treatments and a year of HER2-targeted therapy with trastuzumab and pertuzumab. Genetic testing also identified a likely pathogenic germline BRCA1 mutation. At 4.5 years of follow-up, she remained free of breast-cancer recurrence and the blood disorder had not returned. Her course shows how a serious treatment complication can require its own prolonged management while effective cancer treatment continues.