Follicular dendritic cell sarcoma complicated by hyaline‐vascular type Castleman's disease in a schizophrenic patient

Follicular dendritic cell (FDC) sarcoma is an exceedingly rare neoplasm of unknown pathogenesis. A case of FDC sarcoma complicated by the hyaline‐vascular type Cattleman's disease occurring in a schizophrenic male is presented. Swelling of the left cervical lymph node appeared In a 44‐year‐old male schizophrenic who had been reeducated with major tranquilizers for 20 years. He had had a history of cervical lymphadenopathy 14 years before, for which a diagnosis of hyaline‐vascular type Castieman's disease had been made. The present specimen, obtained from the same site, was an enlarged lymph node heavily infiltrated with oval to spindie‐shaped atypical cells but was uninvolved at the periphery. The infiltrating cells showed nodular or sheet‐like growth, occasionally taking fascicular or storiform patterns. Follicular Involvement was also common. Peculiarly, varlous amounts of small lymphocytes were Intermingled with the neopiastic cells. The atypical cells expressed two FDC‐specific antigens, DRC‐1 and K1–M4 antigen, together with a few other markers that are shared by FDC, Including CD21 and HLA‐DR. These findings ciearly show the tumor to be FDC sarcoma. in addition, a peculiar fibro‐hyalinous change in the lymph follicle, which is compatible with hyallne‐vascular type Cattleman's disease, was noted at the periphery of the lymph node where neoplastic cells had not infiltrated. Surprisingly, similar hyaline‐vascular changes were observed in the previous biopsy taken 14 years ago. Meanwhlle, Kaposi's sarcoma‐associated herpesvirus, which is often Identified from generalized Castieman's disease, was not identified in the present case by polymerase chain reaction study. Thus, this case is unique in two aspects: (I) the overlap of FDC sarcoma with hyaline‐vascular type follicular changes: and (II) Its Occurrence in a schirzophrenic patient.