Basal cell carcinoma (BCC) is the most common cancer in Caucasians. It is slow growing and rarely metastasizes. If left untreated over time, invasive growth can occur. We present a patient case with a primary BCC located in the right sub-mammary area, with extensive metastases to the skeleton and bone marrow. Histopathological examination of the tumour showed BCC with a diverse growth pattern. There were no signs of local metastases. Surgery was successfully performed. Three months post-surgery the patient developed normocytic anaemia and elevated inflammation markers. [18F]FDG PET/CT showed extensive FDG uptake in the entire skeleton and bone marrow. Biopsy confirmed the infiltration of BCC with similar histopathological features as the primary tumour. Prognosis of metastasized BCC is poor and, therefore, long-term follow-up of patients with risk factors is of importance.
Keywords: basal cell carcinoma; bone marrow invasion; bone marrow metastasis; nonmelanoma skin cancer.