intracyctic papillary carcinoma of the breast: report of a rare case and literature review

Introduction: we present a rare case of breast papillary carcinoma associated with intracystic component in a woman with a long history of autoimmune hypothyroidism and multiple sclerosis. case presentation: the patient was a 59-year-old woman presented with complaints of pain and swelling in her right breast. she was a known case of autoimmune hypothyroidism since 20 years and secondary progressive multiple sclerosis since 13 years ago. she had received frequent interferon, corticosteroid and cytotoxic therapy for her multiple sclerosis. onimaging studies, there were multiple large cystic-solid lesions in the right breast and with presumptive diagnosis of infectious collection or phyllodes tumor, she finally underwent simple mastectomy. on gross pathological evaluation, a large multi-loculated cyst filled with blood clots and necrotic debris was identified. in serial sections, a 7cmsolid tumoral mass with papillary projections protruding into the cyst cavity was seen. although the gross appearance of the lesion resembled an angiosarcoma accompanied by cystic hemorrhagic necrosis, after the microscopic evaluation of the specimen, papillary breast carcinoma associated with intracyctic component was finally diagnosed. conclusions: the aim of this study was to describe a rare variant of invasive breast cancer presenting with a large solid-cyctic mass in a woman with long standing autoimmune disorders.