Abstract
Autoimmune diseases and malignancies share complex immunological interactions, but their coexistence in a single patient presents unique diagnostic and therapeutic challenges. We report the case of a 65-year-old woman with a history of autoimmune disease who presented with a locally advanced carcinoma of the breast. Despite ongoing immunosuppressive therapy, she developed a flare of autoimmune manifestations during the progression of her malignancy. The patient underwent surgical resection of the primary tumor, which not only achieved local oncological control but also resulted in a marked improvement of her autoimmune symptoms postoperatively. This case highlights the dual nature of the immune system in cancer, where immune dysregulation contributes both to tumor progression and to autoimmunity. The clinical course of our patient suggests that tumor antigens may serve as a chronic stimulus for immune activation, thereby exacerbating autoimmune flares. Surgical resection eliminated the source of antigenic stimulation, leading to symptom resolution, underscoring the potential therapeutic role of surgery beyond oncological benefit. Recognition of autoimmune disease exacerbations as a manifestation of underlying malignancy is crucial, as they may mimic paraneoplastic syndromes and delay appropriate treatment. A multidisciplinary approach involving oncologists, surgeons, and rheumatologists is essential for optimal care in such complex cases. This report adds to the limited literature on autoimmune disease flares associated with breast carcinoma and suggests that timely surgical intervention can achieve disease control on two fronts, cancer progression and immune dysregulation.