Abstract
A 64-year-old man with a positive occult blood test was diagnosed with rectal cancer based on detailed examinations, but abdominal contrast-enhanced computed tomography (CT) showed a tumor approximately 2 cm in size in the spleen, and metastasis of rectal cancer could not be ruled out. Therefore, laparoscopic rectal resection and splenectomy were performed for rectal cancer (Rb) and suspected metastatic splenic tumor. The pathological diagnosis was tub2>tub1, pMP, ly0, v0, pN0, Stage I for the rectal cancer, while in the splenic tumor, spindle cells were proliferating in a fascicular pattern with underlying severe infiltration of lymphocytes and plasma cells. Immunostaining was positive for CD21, CD35, and CD23, as well as EBER-1, and the patient was therefore diagnosed with Epstein-Barr virus (EBV)-associated inflammatory pseudotumor-like dendritic cell sarcoma.
EBV-associated inflammatory pseudotumor-like dendritic cell sarcoma is extremely rare, and a literature search identified only 11 reported cases in Japan and abroad. This case of EBV-associated inflammatory pseudotumor-like dendritic cell sarcoma of splenic origin that was detected during detailed examination prior to surgery for rectal cancer is reported along with the relevant literature.
