A Rare Case of Synchronous Breast Carcinoma and Mantle Cell Lymphoma: Successful Treatment of Both Cancers with Bendamustine/Rituxan Combination

We present a rare case of a 64 year old female with a synchronous diagnosis of breast carcinoma and ipsilateral, diffuse mantle cell lymphoma. At the time of diagnosis, the lymphoma was deemed to pose more of an overall risk to the patient and an initial treatment with bendamustine/Rituxan was begun. After 3 cycles, a repeat PET CT showed a significant decrease in tumor burden from the lymphoma as well as a significant reduction of the breast carcinoma tumor size and FDG avidity. A literature review showed some evidence that the pathogenesis of breast carcinoma and mantle cell lymphoma may share some common pathways. Further research into the effectiveness of Bendamustine as an adjuvant chemotherapy regiment for patients with synchronous breast carcinoma could prove useful in clinical practice.