Follicular dendritic cell sarcoma of small intestine with aberrant T-cell marker expression.
Follicular dendritic cell sarcoma (FDCS) is an uncommon neoplasia usually occurring in lymphoid tissue. Herein is presented a case of FDCS of the small intestine with positivity for T-cell antigen, simulating T-cell lymphoma. An 82-year-old man consulted a doctor for a 1 week history of epigastric pain. Imaging indicated a mass in the small intestine. Malignant lymphoma was suspected because of high serum levels of soluble interleukin-2 receptor, and resection of the tumor was performed. Microscopically the tumor consisted of large pleomorphic cells with reactive small lymphocytes. Most of the nuclei of the tumor cells were round or ovoid, and some of the tumor cells also had spindle-shaped nuclei. Although the tumor cells were diffusely positive for CD45RO and CD4 on immunohistochemistry, negativity for pan-T-cell markers and CD56 was unusual for T-cell lymphoma of intestinal origin. Additional immunohistochemistry demonstrated that the tumor cells were positive for follicular dendritic cell markers including CD23, CD35 and CAN.42, and diagnosis of FDCS was made. To the authors' knowledge this is the first case of FDCS aberrantly expressing CD45RO; FDCS expressing T-cell markers can be a pitfall for diagnosis of FDCS.
Yamada
Yosuke
Y
Department of Surgical Pathology, Hokkaido University Hospital, Sapporo, Japan.
Haga
Hironori
H
Hernandez
Mako
M
Kubota
Kanako C
KC
Orii
Fumika
F
Nagashima
Kazuo
K
Matsuno
Yoshihiro
Y
D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000276:immunology*; D054740:Dendritic Cell Sarcoma, Follicular / Q000276:immunology* / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D007414:Intestinal Neoplasms / Q000276:immunology* / Q000473:pathology; D007421:Intestine, Small / Q000276:immunology* / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000473:pathology; D008297:Male; D013601:T-Lymphocytes / Q000276:immunology* / Q000473:pathology
D014408:Biomarkers, Tumor