Fine needle aspiration cytology in follicular dendritic cell sarcoma:areport of two cases
BACKGROUND: Since the first description of extranodalfollicular dendriticcell sarcoma in 1994, there has been a gradual increase in understanding of the morphologic featuresand clinical presentation of this tumor. However, difficulties persist in making cytologicdiagnosis. CASES: Two cases of follicular dendritic cell sarcoma with fine needle aspirationcytology (FNAC) findings were reported. The first patient was a Chinese woman who presented with aright tonsillar mass, which was followed by right submandibular recurrence. The second patient was aChinese man with known history of Castleman’s disease of the nasopharynx complicated by folliculardendritic cell sarcoma, followed by tumor recurrence in cervical lymph nodes. FNAC of both recurrentcases showed isolated or syncytial sheets of tumor cells containing eosinophilic granularcytoplasm, ill-defined cell borders, round to oval nuclei, solitary round eosinophilic nucleoli andfine chromatin. CONCLUSION: The tumor cells in follicular dendritic cell sarcoma show cytologicfeatures reminiscent of native follicular dendritic cells but with a greater than expected cellnumber and nuclear pleomorphism. These cells may be immunohistochemically inert for folliculardendritic cell markers CD21 and CD35. A presumptive diagnosis on the basis of cytologic examinationis possible when paying attention to the subtle morphologic features.
Fan,YS　Ng,WK　Chan,A　Chan,GS　Tsang,J　Chim,CS　Ip,P
Department of Pathology and Clinical Biochemistry, Queen Mary Hospital, HongKong SAR, China. fanyuenshan@hotmail.com
Dendritic Cells　 Malignant neoplasm musculoskeletal　 Neoplasms Fine needlebiopsy, NOS
