Occult Breast Cancer Masquerading as Bicytopenia

Abstract Occult breast cancer (OBC) is a rare type of breast cancer without a detectable primary lesion in the breast on a physical examination or imaging such as an ultrasound or mammogram. Occult breast cancer may present as axillary lymphadenopathy, nipple discharge, nipple dermatitis, papillary dermal edema, eczema, skin retraction, etc. However, anemia and thrombocytopenia as the initial presentation of OBC are rare. We report the rare case of a patient with OBC who presented with significant thrombocytopenia and anemia due to bone marrow metastasis.