A case of primary hepatic mucosa-associated lymphoid tissue lymphoma incidentally found in the sustained virological response state of chronic hepatitis C: review of the literature of this rare disease.

A 54-year-old woman finished the treatment for chronic hepatitis C and achieved sustained virological response. She was identified with some tumor lesions at her liver during follow-up observation by ultrasonography. From contrast-enhanced computed tomography, there were four tumors at sub-segment 4/5, S5, S6, and S7. These lesions are slightly enhanced on arterial phase and washed out on delayed phase. Contrast-enhanced magnetic resonance imaging showed slight enhancement on arterial phase and defect on hepatocyte phase. Tumor markers including alpha fetoprotein, Des-Gamma-Carboxy Prothrombin, carcinoembryonic antigen, and carbohydrate antigen (CA19-9) were within normal range. The patient underwent partial hepatectomies of four tumors at S4/5, S5, S6, and S7. The patient was recovering well, so he discharged our hospital after 10 days from the operation. The histological assay of the resected specimen showed accumulation of lymphocyte with hyperplasia of lymphoid follicles accordant with tumor lesions. Immunohistochemical staining assay revealed a positive for CD3, CD20, CD10, and bcl-2. These findings eventually made a diagnosis of all four tumors as mucosa-associated lymphoid tissue lymphoma. Since previously published case reports and our case described nonspecific clinical features of this rare disease, it was difficult to get the certain diagnosis before histological confirmation and non-anatomical partial liver resection may be a good choice for both diagnosis and local therapy. © The Japan Society of Clinical Oncology 2020.