title: Extranodal follicular dendritic cell sarcoma with rapid growth in parapharynx: a case report.
abstract: Follicular dendritic cell sarcoma (FDCS) is a rare malignancy arising from the antigen-presenting cells in the lymph node and extranodal tissue. We describe a 31-year-old male patient who presented with a swelling of the left parapharynx. The radiologic findings showed a 4.7×4.5×1.9 cm-sized, ill-defined mass in the left parapharyngeal space. A fine-needle aspiration cytology was performed and it showed scattered, irregular, cohesive clusters of tumor cells with a spindle-to-ovoid shape with irregular contours in a background of lymphocytes. Based on these findings, a diagnosis of spindle cell neoplasm was made. The surgically resected tumor was composed of elongated, ovoid or polygonal cells showing positive immunohistochemistry for CD21, CD23, and CD35. Postoperatively, the residual tumor was observed to undergo a rapidly growth. There is an overlap in the cytologic and histologic findings between FDCS of the parapharynx and other tumors. Pathologists should therefore be aware of its characteristics not only to provide an accurate diagnosis but also to recommend the appropriate clinical management.
authors.affiliation: Department of Pathology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jung-Soo
authors.initials: JS
authors.lastname: Pyo
authors.forename: Guhyun
authors.initials: G
authors.lastname: Kang
authors.forename: Sung-Im
authors.initials: SI
authors.lastname: Do
authors.forename: Seoung Wan
authors.initials: SW
authors.lastname: Chae
authors.forename: Kyungeun
authors.initials: K
authors.lastname: Kim
authors.forename: Sang Hyuk
authors.initials: SH
authors.lastname: Lee
authors.forename: Yoon-La
authors.initials: YL
authors.lastname: Choi
authors.forename: Joon Hyuk
authors.initials: JH
authors.lastname: Choi
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Sohn
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Kim
keywords: Dendritic cell sarcoma, follicular; Extranodal; Parapharynx