Inflammatory pseudotumor of the liver. Report of two cases.

Inflammatory pseudotumor (IPT) is a rare lesion of the liver. We report two cases of IPT of the liver. Patients were a 32-year-old man and a 45-year-old female. Preoperative clinical diagnoses were respectively amebic abscess and metastatic tumor. Fine needle aspirations were performed and cytopathologic findings were compatible with an inflammatory process in both cases. Simple excision was performed in the first case and left lobectomy in the second one. Gross examination revealed expansive solid tumoral masses which measured 3 x 2 x 2 cm and 7 x 5 x 5 cm, respectively. Both lesions were yellow and firm. On microscopic examination, lesions were composed of fascicles of plump spindle cells intermingled with a varying number of plasma cells, lymphocytes and histiocytes. The spindle cell fascicles also contained a moderate amount of intercellular collagen. No microorganism was found on PAS, Giemsa, Grocott and Ziehl Nielsen stained sections. Plasma cells were immunoreactive for both kappa and lambda light chains, revealing their polyclonal nature. Since hepatocellular carcinoma is concerned in differential diagnosis, IPT is of particular clinical importance. Despite the limited experience with fine needle aspiration cytology, histopathologic diagnosis of IPT does not pose great difficulty.