Summary

The association of metastatic breast cancer presenting as thrombocytopenia and anaemia is demonstrated in the following case of a 79-year-old woman. Her main symptoms were abdominal pain, altered bowel habit and weight loss. Without a clear causative pathology, she underwent a CT scan which demonstrated multiple sclerotic bone lesions. With a raised CA15-3 and strong oestrogen receptor positivity on immunohistochemistry on a trephine bone marrow biopsy, a diagnosis of metastatic lobular breast cancer was made. Interestingly, only a small breast mass was noted on mammography. The patient was managed conservatively and initiated on supportive therapy. This case report summarises the varying presentation of bone marrow suppression secondary to metastatic infiltration, especially in the absence of classical symptoms associated with primary solid tumour. Accurate bone marrow analysis is also vital in establishing the final diagnosis.