Synchronous lymph node involvement by metastatic carcinoma and lymphoma

[摘要] A 74-year-old female was referred for evaluation of axillary lymphadenopathy found on routine screening mammography. Suspicion for lymphoma involvement was raised. The consequent lymphnode biopsy showed synchronous involvement by small lymphocytic lymphoma (SLL) and poorly differentiated metastatic carcinoma ofunknown origin. Lymph node flow cytometry was consistent with lymphoma involvement. Core needle biopsy (Figure 1, top left) showslymphoid tissue heavily infiltrated by large, pleomorphic cells with prominent nucleoli in a background of small monomorphous lymphocytes with irregular nuclear borders concerning for lymphoma. The carcinoma component was positive for CK903 (Figure 1, top center) andp40 and negative for ER, PR, and GATA3, where lymphoma component was positive for CD23 (Figure 1, top right), CD5 (Figure 1, bottomleft), and CD20 (Figure 1, bottom center) and negative for SOX11 andCyclinD1 (Figure 1, bottom right).