Adjuvant chemotherapy in breast cancer

Breast cancer after multiple myeloma treatment

Breast cancer is the most common cancer in women. In addition, it is the second leading cause of death after lung cancer.^1,2 The prevalence of epidemiological studies in previous studies is 22%-26%. The risk of mortality due to breast cancer is around 18%.^3,4 Multiple myeloma (MM) is a malignant disease of differentiated plasma cells. It is also the most common hematological neoplasm after lymphoma. Thirty five percent of MM patients are under the age of 65, 28% are between 65 and 74 of age and 37% are over the age of 75.⁵ Pathophysiological mechanisms of MM include abnormal plasma cells (myeloma cells) occupying bone marrow, producing monoclonal immunoglobulin (M protein, M-component, and paraprotein) and increased bone destruction.⁶ Breast cancer cases diagnosed concurrently with myeloma have been reported in previous case reports. There is also a patient diagnosed with myeloma following breast cancer chemotherapy. In our case, the patient was first diagnosed with MM. And then autologous bone marrow transplantation was performed following 3 cycles of chemotherapy. This presentation is unique, because in literature there is no breast cancer case after myeloma in literature review.