Abstract
Multiple primary malignancies (MPMs) are defined as two or more histopathologically distinct malignancies in the same individual. MPMs are classified as synchronous when tumors are diagnosed within six months of each other. The most common malignancies in MPMs are melanoma, breast, lung, and prostate cancer. Synchronous lymphoma and solid tumors are relatively rare. In these cases, a multi-disciplinary approach to treatment is essential. The early detection of additional primary malignancies such as myeloid and lymphatic tumors will enable prompt management with curative intent. The authors present a case of diffuse B-cell non-Hodgkin lymphoma and invasive lobular breast carcinoma presented as a chylous pleural effusion.