A case of hepatic pseudolymphomaLiu chenhan Department of radiology, Sir Run Run Shaw HospitalCASE:1443371CASE:1443371n nF,64Y，体检发现肝脏肿物半月余。n n症状、体征（-）n n既往：肝段血管瘤 n n辅检：辅检：LABLAB肿瘤女肿瘤女肿瘤女肿瘤女-6-6：(2014-08-01),(2014-08-01),癌胚抗原癌胚抗原癌胚抗原癌胚抗原CEACEA：5.36ng/ml(0-5ng/ml)5.36ng/ml(0-5ng/ml)；肝酶指标（；肝酶指标（；肝酶指标（；肝酶指标（- -） 乙肝表面抗原：乙肝表面抗原：乙肝表面抗原：乙肝表面抗原：117 IU/ml117 IU/ml 乙肝核心抗体乙肝核心抗体乙肝核心抗体乙肝核心抗体IgGIgG：13.36 COI 13.36 COI n腹部腹部B超超:左肝外叶低弱回声结节，建左肝外叶低弱回声结节，建议超声造影；议超声造影；n n胃镜：慢性轻度浅表性炎，灶性肠化，幽胃镜：慢性轻度浅表性炎，灶性肠化，幽门螺杆菌：阴性门螺杆菌：阴性n n肠镜：（肠镜：（-）eWorldView ImageeWorldView ImagenCT:左肝II段边缘可疑稍低密度灶，请结合其它检查或复查。nMR:左肝外侧叶占位，恶性病灶不能排除，转移？或其他。n腹腔镜左肝肿块切除+术中冰冻 n术中未见明显腹水，肝脏无明显结节性改变，左肝外侧叶可见一大小约2cm肿块，略突出于肝脏表面，质软，边界尚清，剖开肿瘤，切面灰黄色，送术中冰冻提示：淋巴细胞增生，淋巴瘤待排。 n n冰冻送检肝组织一块，冰冻送检肝组织一块， 3.8*3*1.5cm3.8*3*1.5cm，剖面见一灰白结节，剖面见一灰白结节，1.7*1.5cm1.7*1.5cm，镜示，镜示结节内淋巴组织增生，淋巴滤泡形成，生结节内淋巴组织增生，淋巴滤泡形成，生发中心可见，大小不等，局部伴小血管增生，结节周围围发中心可见，大小不等，局部伴小血管增生，结节周围围绕以不连续的纤维组织包膜，包膜局部见淋巴组织浸润，绕以不连续的纤维组织包膜，包膜局部见淋巴组织浸润，周围肝组织汇管区内亦可见成片淋巴细胞浸润周围肝组织汇管区内亦可见成片淋巴细胞浸润。免疫组化。免疫组化（B B片）：片）：CD3 & CD20 & CD5 & CD10 & CD43 & CD15 & CD3 & CD20 & CD5 & CD10 & CD43 & CD15 & CD21 & CD23 & CD30 & Bcl2 & Bcl6 & Kappa & Lambda & CD21 & CD23 & CD30 & Bcl2 & Bcl6 & Kappa & Lambda & Ki67Ki67：未见异常表达，：未见异常表达，EBEREBER：，：，D240D240：内皮细胞：内皮细胞+ +。n nBCRBCR：IgHIgH基因重排：基因重排：Fr2A+Fr2BFr2A+Fr2B：阴性；：阴性；Fr3AFr3A：阴性；：阴性；IgKIgK基因重排：阴性。基因重排：阴性。n n（肝）淋巴组织反应性增生，考虑为假性淋巴瘤backgroundbackground nPseudolymphoma(PL) was first described in the lung by Salt-zstein in 1963 as a lymphocytic tumor associated with inflammation and with no evidence of systemic dissemination. nPL of the liver was first reported by Snover et al in 1981.n PL can be found in the gastrointestinal tract,orbit,and pancreas,but rarely in the liver.background background nHepatic pseudolymphoma (HPL),also termed as reactive lymphoid hyperplasia, or nodular lymphoid lesion. nHPL has benign behavior.nHPL is an extremely rare condition, with most reports to date dealing with single cases. EtiopathogenesisEtiopathogenesisnThe exact etiology remains unknown.nIt is speculated that chronic infection or inflammatory process suggests their correlation with immunological response.nHPL can develop in patients with autoimmune diseases, malignancy, or hepatitis or who are administered interferon therapy. nBased on a review of the PubMed database from 1981 to 2012 using the keywords “pseudolymphoma” and “lymphoid hyperplasia of the liver”, we found 64 lesions in 46 cases of pseudolymphoma.Literature reviewLiterature reviewnF/M: 42:5 nMost of the cases (69.6%) were reported in Japan.nThe average size of the tumor was 15.1+/- 10.6 mm, most of the tumors (90.6%) were no more than 20 mm.nMost of the lesions reported are single in number.Imaging findingsImaging findings nOn CT, a hypodense mass on unenhanced images that is slight enhanced on early-phase images after contrast injection and subsequent washout.nOn MRI, slight T1 and T2 prolongation and restricted diffusion.PathologicalPathological featuresfeaturesnHPL consisted of tumorous infiltrates of mature lymphocytes with multiple lymph follicles or clusters of epithelioid histiocytes. Lymphocytes characteristically extended into nearby portal tracts. No obvious atypical cells were identified.n Ductal structures positive for cytokeratin 7 were entrapped in the peripheral parts of nodules. In situ hybridization of immunoglobulin light chains revealed B lymphocytes and plasma cells to be polyclonal. In addition, clonal rearrangements of immunoglobulin heavy chains could not be shown in any cases using PCR. At the edge of the nodule, lymphocytic infiltration extends into perinodularportal tracts (left). Compared with the background liver with chronic hepatitis B (right), lymphocytic infiltration is more pronounced in the portal tracts around the nodule diagnosisdiagnosisnThe diagnosis of hepatic pseudolymphoma can be challenging but might be aided by in situ hybridization,analyses of gene rearrangements, or follow-up based on images.TreatmentTreatment Since clinical diagnosis is often difficult especially at its earlier stage, surgical resection appears a mainstay for diagnostic/therapeutic purpose.CASE 1CASE 1n F,49Y, The abdominal ultrasonography showed a hypoechoic lesion, about 20*16*14 mm in size, located in segment 2.nhepatic enzymes(-); HBV surface antigen and HCV antibody were both negativenAFP, CEA, and CA-199 (-)(A)(CT) scans showed a 20-mm-diameter, slightly hypodense mass with peripheral rim enhancement in arterial phase located in segment 2.(B) (B) Early washout of the contrast medium with retained ring enhancement was seen in the portal phase. (C) Axial magnetic resonance (MR) imaging showed a hypointensenodule on segment 2 of the liver in the T1-weighted image, and (D) the lesion became hyperintense in the T2-weighted image. (E) Arterial portography with computed tomography demonstrated a perfusion defect in segment 2 of the liver. Angiography showed a hypervascular lesion on segment 6 of the liver (arrow). (F) However, the small tumor in segment 2 of the liver on previous CTand MR had no definite tumor stain.n A hypovascular tumor was impressed,and peripheral type cholangiocarcinoma, metastatic tumor, or sclerosed hemangioma should be differentiated.n A left lateral sectionectomy was performed.Figure 2Pathological findings of the lesion. Gross pathologic specimen revealed a well-defined, nonencapsulated, yellowish-white, and soft hepatic tumor, located just beneath the capsule in segment 2 of the liver.nHistopathology of hepatic pseudolymphoma. Hematoxylineeosin-stained histological images showed that the mass wasncomposed of hyperplastic lymphoid tissue with several enlarged, irregularly shaped, well-demarcated follicles with formation ofngerminal centers distributed evenly in the mass. (A) The lymphocytes containing round nuclei with scant cytoplasm are mainlynsmall in size and mature in appearance with scattered medium and large cells, ?40. Immunohistochemical stain showed that thengerminal centers were composed of B lymphocytes (B) positive to CD20 antibody, ?100, (C) but negative to Bcl-2 (e) antibody,n?100. (D) The interfollicular area was composed of small T lymphocytes positive to CD3 antibody, ?100. (E) Reactive immunoblastsnpositive to CD30 antibody were evenly distributed in the interfollicular region, ?100. (F) However, the EpsteineBarr virus-encodednRNA stain was negative, ?40. CD20 (+), B cellsBcl-2 (-) B cells CD3 (+) small T cellsReactive CD30 (+) immunoblastsEpsteineBarr virus-encoded RNA(-)nThe patient received regular follow-up, and no recurrence was found during 5 years of follow-up.CASE 2nF,63Y, had a history of PBC and resection of the left adrenal gland for primary aldosteronism.nShe was asymptomatic on admission and her condition was generally good.nAbdominal ultrasonography showed a hypoechoic lesion,10 mm in diameter in segment 7 .nLaboratory tests(-)A: A hypodensenodule in plane phase; B: A hyperdense nodule in the early phase after injection of contrast medium;C: A hypodense nodule in the late phase after injection of contrast medium.nhypointense nodule on T1-weighted images;n A hyperintense nodule on T2-weighted images;nA hyperintense nodule in the early phase after injection of contrast medium; nA hypointense nodule in the late phase after injection of contrastnmedium.nSuperparamagnetic iron oxide-enhanced MRI showing hyperintense nodules.A: 10 mm nodule in segment 7; B: 4 mm nodule in segment 6.nCT during arterial portography showing hypointense nodules. A: 10 mm nodule in segment 7; B: 4 mm nodule in segment 6.n Imaging findings suggested HCC, although no other hypervascular tumor could be excluded.n A right posterior segmentectomy was performed. Macroscopically, the lesion in segment 7 was white and hard with clear margins. Microscopically,the lesion consisted of a nodular lymphoid infiltrate with germinal centersnMacroscopically, the lesion in segment 7 was white and hard with clear margins. nMicroscopically,the lesion consisted of a nodular lymphoid infiltrate with germinal centers nIn situ hybridization revealed no significant difference between the numbers of cells positive for kappa-chain and lambda-chain CD3(+) T-cellsCD20(+) B-cellsStained for light chains Stained for light chains The patient had an uneventful postoperative course and has shown no sign of recurrence for 11 M.SummarySummarynHPL should be considered in the differential diagnosis of small hepatic tumors (20 mm), especially when a single hypovascular tumor is found in a female patient who associated with either autoimmune disease or chronic liver disease,and the patient has no risk factors of hepatocellular carcinoma.eWorldView Image