Malignant mesothelioma is a cancer of a human body serous membranes. It is uncommon and can frequently cause diagnostic and therapeutic problems. Common clinical symptoms include shortness of breath, cough and chest pain. Loss of appetite and fatigue appear in late‑stages of the disease. Key element of diagnosis is biopsies with sampling. In some cases, receiving a satisfactory microscopic examination result can be a great challenge. Asbestos exposure is a proved risk factor for mesothelioma. Mesothelioma is an aggressive cancer with short survival time and poor prognosis. Breast metastases of malignant mesothelioma are extremely rare. The diagnostic and therapeutic path was analyzed, taking into account difficulties and limitations of the therapy. In most cases treatment is palliative and limited to managing pleural effusion.