Diagnosis and treatment of metachronous multiple primary carcinoma: A case report and review of literature.

Background: Multiple primary carcinoma (MPC) refers to two or more types of primary malignant tumors occurring simultaneously or sequentially in the same patient. Breast cancer is one of the most common malignant tumors affecting women. On the other hand, diffuse large B-cell lymphoma (DLBCL) is the most frequent form of non-Hodgkin's lymphoma (NHL). In clinical practice, the simultaneous existence of metachronous primary breast cancer and lymphoma is rare. In this case, we highlight the significance of multidisciplinary management and advanced imaging techniques in the early identification and treatment of MPC cases.

Case summary: In this study, we report a case of a 40-year-old female who was diagnosed with invasive ductal carcinoma of the breast (T3N1M0 stage IIIA LuminalB type) as the first primary cancer and DLBCL (stage IIIA) as the second primary cancer. The patient underwent the modified radical mastectomy for left breast cancer and received Rituximab, cyclophospha-mide, hydroxydaunorubicin, Oncovin (vincristine) and prednisolone regimen chemotherapy treatment for DLBCL. As of now, the patient is in stable condition. The successful diagnosis of the present patient highlights the need for multidisciplinary management and adoption of advanced imaging techniques to identify the second primary cancer, especially NHL.

Conclusion: Accurate diagnosis and management of metachronous MPC requires an interdisciplinary team and selection of an appropriate treatment plan.