Diffuse large B cell lymphoma (DLBCL) presenting as a spindle cell tumor of the liver: a case report

Diffuse large B cell lymphoma (DLBCL) may present rarely as a spindle cell tumor. Only one previous case of spindle cell DLBCL involving the liver has been reported. We present a case of primary hepatic DLBCL with spindle cell features in a 67-year-old man who initially presented with elevated liver enzymes and an indistinct liver mass identified by computed tomography. The lesion was diagnosed by needle biopsy as an inflammatory pseudotumor at an outside hospital and repeat imaging suggested that the lesion had decreased in size. Thus, no treatment was given. Seven months later, he presented with jaundice and additional porta hepatic mass and lymphadenopathy. A surgical resection was performed. Microscopically, the liver mass, bile duct mass, and lymph nodes demonstrated a spindle cell infiltration interspersed with small and large lymphocytes, and eosinophils in a fibrotic background. One lymph node showed focal architectural effacement by large atypical lymphoid cells. Immunohistochemical staining of the lymph node and liver mass revealed that the tumor cells were positive for CD20, BCL-6, CD79a, and PAX-5. Proliferation index (Ki-67) ranged from 70 to 90 %. We concluded that both the liver and lymph nodes were involved by spindle cell DLBCL. This case is presented to underscore the importance of including DLBCL in the differential diagnosis of spindle cell lesions, especially those found in unusual locations such as the liver.