A case of primary hepatic extranodal marginal zone B-cell mucosa-associated lymphoid tissue (MALT) lymphoma treated by radiofrequency ablation (RFA), and a literature review

Abstract

Primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma is an extremely rare liver malignancy that usually lacks characteristic imaging findings and which is often misdiagnosed. We report a 63-year-old woman diagnosed with primary hepatic extranodal marginal zone B-cell lymphoma, MALT type. The patient underwent needle biopsy and radiofrequency ablation (RFA), and showed no signs of relapse during the 12-month postoperative follow-up. This case stresses the rarity of primary hepatic MALT-type lymphoma and the unique and effective treatment for this patient. Our patient received RFA, which showed good efficacy and which provides a new option for the treatment of hepatic MALT lymphoma. We also present our findings from a systematic review to improve the current understanding of this disease.

Keywords: Primary hepatic lymphoma; cancer; fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography; marginal zone B-cell lymphoma; mucosa-associated lymphoid tissue lymphoma; radiofrequency ablation.

Figure 1.

Enhanced magnetic resonance imaging findings. The mass demonstrated high signal intensity on T2-weighted imaging (a). The mass was slightly enhanced in the arterial phase (b) and washed out in the portal phase (c). The lesion showed low signal intensity in the hepatocyte-specific phase (d). Contrast-enhanced ultrasonography showed mild inhomogeneous hyperenhancement in the arterial phase (e) and wash-out in the portal phase (f).

Figure 2.

Histological examination findings. The lesion consisted of dense lymphocyte infiltration with lymphoepithelial lesions in the bile ducts (a, arrow; hematoxylin and eosin (HE), ×400). Lymphocytes were positive for cluster of differentiation (CD)20 (b), B-cell lymphoma-2 (Bcl-2) (c), and CD21 (d) antibodies. Histological evidence of bile duct injury and ductal proliferation was highlighted by cytokeratin AE1/AE3 immunostaining (e). The Ki-67 labeling index was approxiamtely 5% (f).

Figure 3.

Postoperative abdominal computed tomography showing effective results of ablation position (a). Enhanced MRI findings 12 months after radiofrequency ablation (RFA) were as follows: no abnormal signal on T2-weighted imaging (b), and no wash-in in either the arterial phase (c) or portal phase (d).