Tumour-to-tumour metastasis: male breast carcinoma metastasis arising in an extrapleural solitary fibrous tumour - a case report

Background Tumour-to-tumour metastasis (TTM) occurs when one tumour metastasises to a separate tumour within the same individual. TTM is observed frequently in breast cancer but has not been described in male breast cancer. In addition reports describing solitary fibrous tumours (SFT) of the pleura hosting other neoplasms’ metastases are limited. We report an exceptional case of male breast cancer metastasising to an extrapleural SFT, occurring in the subcutaneous tissue of the back of a 68-year old Caucasian patient.