Reactive lymphoid hyperplasia of the liver in a patient with colon cancer: report of two cases

Reactive lymphoid hyperplasia of the liver after surgery for advanced sigmoid colon cancer: a case report

We report a case of reactive lymphoid hyperplasia (RLH) mimicking colorectal liver metastases (CRLM) on preoperative workup that was clinically indistinguishable. A 78-year-old woman was found to have locally-advanced sigmoid cancer (T4), and then treated with radical sigmoidectomy. One year after the surgery, plain computed tomography (CT) revealed a low-density area in the right hepatic lobe. Metastatic liver tumors could not be ruled out with CT/ magnetic resonant imaging (MRI) and positron emission tomography-CT . Based on these findings, the patient was diagnosed with CRLM at S7 of the liver. The patient underwent right posterior sectionectomy. The tumor was adjacent to the right hepatic vein; however, no invasion was observed. The patient was pathologically diagnosed as having RLH. The patient showed no signs of recurrence 16 months after initial surgery. RLH is clinically indistinguishable from CRLM. Further evaluation is required to elucidate the effective strategies of detecting and treating hepatic RLH.

A case of difficult-to-diagnose hepatic reactive lymphoid hyperplasia finally diagnosed by using PCR analysis of IgH-gene rearrangements: a case report

Reactive lymphoid hyperplasia (RLH) of the liver is extremely rare. Despite advancements in diagnostic imaging technology, it is still difficult to distinguish from hepatocellular carcinoma (HCC). Herein, we present a case of hepatic RLH mimicking HCC that was postoperatively diagnosed using several imaging modalities. A 78-year-old female was referred to our hospital with a positive hepatitis C virus antibody (HCV Ab) test. Ultrasonography revealed a 13 mm isoechoic lesion in segment 8 of the liver. Contrast-enhanced computed tomography (CE-CT) demonstrated arterial hyperintensity and washout during the later phase. On ethoxybenzyl magnetic resonance imaging (EOB-MRI), the lesion was hyperenhanced in the arterial phase and of low intensity in the hepatocyte phase. Although the tumor markers were all within normal limits, the pattern of contrast enhancement of the tumor on CT and MRI was consistent with that of HCC. We performed S8 segmentectomy of the liver. Histological examination of the resected specimen revealed dense lymphoid tissue of variable sizes and shapes with expanded germinal centers. Immunohistochemical examination was positive for CD3, CD10 (germinal center), and CD20, and negative for B-cell lymphoma 2 (bcl-2) (germinal center) and Epstein-Barr virus (EBV). A polymerase chain reaction (PCR) analysis of IgH-gene rearrangements revealed polyclonality. Based on these findings, hepatic RLH was diagnosed. The postoperative course was uneventful, and the patient was discharged on the 10th postoperative day. She had a good quality of life after surgery and no liver nodule recurrence was detected at the 4-month medical follow-up. Hepatic RLH is an extremely rare disease and preoperative diagnosis is difficult. This should be considered in the differential diagnosis of single small hepatic tumors. An echo-guided biopsy and careful observation of imaging may help diagnose hepatic RLH, and a PCR analysis of IgH-gene rearrangements would be necessary for the definitive diagnosis of hepatic RLH.

A case of hepatic reactive lymphoid hyperplasia: the review of 23 cases from the literatures

A 70-year-old woman was referred to our hospital because of slight elevation of soluble interleukin-2 receptor (sIL-2R) and accumulation of 18F-fluorodeoxyglucose (FDG) in S8 of the liver on positron emission tomography. The mass was strongly suspected to be malignant because of contrast enhancement and enlargement in size of the mass, and suspicion of portal vein invasion. Hepatic S8 subsegmentectomy was performed for diagnostic and therapeutic purposes. Hematoxylin and eosin staining of the resected specimen showed small lymphocytes with no atypia and no formation of lymphoid follicles. Immunostaining showed CD3-positive cells in the interfollicular region and CD20-positive cells in the lymphoid follicles. Both CD10 and BCL-2 were negative in the follicular germinal center. CD138-positive plasma cells were observed and there was no light chain restriction. Based on polyclonal growth pattern of lymphocytes in the lymphoid follicles and interfollicular region, she was diagnosed with hepatic reactive lymphoid hyperplasia (RLH).Review of the English literature of hepatic RLH which referred to imaging findings yielded 23 cases, including this case. As a result, we suggest that liver biopsy should be performed for definitive diagnosis, when hepatic RLH is suspected by imaging findings and backgrounds.

Clinical features, natural history and outcomes of pseudolymphoma of liver: A case-series and systematic review

BACKGROUND

Pseudolymphoma is a rare, benign, nonspecific condition that forms a mass-like lesion characterized by the proliferation of non-neoplastic lymphocytes. Lacking of specific clinical symptoms, serological markers, and imaging features, the diagnosis is difficult. We reporte five cases of hepatic pseudolymphoma and provide a systematic review of existing literatures to improve our understanding of this rare liver disease.

METHODS

We followed-up five cases of hepatic pseudolymphoma in West China Hospital from January 2002 to January 2022. We also summarized the cases of hepatic pseudolymphoma from January 1981 to December 2021 through the PubMed database and comprehensively analyzed the characteristics of the cases.

RESULTS

The pathologic features of the five cases were characterized by benign lymphoid tissue hyperplasia, lymphoid follicle formation, and a polarized germinal center. Immunohistochemistry, in situ hybridization, and gene rearrangement revealed non-malignant lymphoma. Besides, a total of 116 cases have been reported in the PubMed database from 1981 to 2021. The incidence of hepatic pseudolymphoma is higher in middle-aged and elderly women and has been reported more frequently in Asia. All cases were pathologically diagnosed, among which 85.95% of the patients were treated by surgery.

CONCLUSIONS

Hepatic pseudolymphoma is an extremely rare benign disease, mainly in middle-aged and elderly women. Without distinctive clinical and imaging characteristics, pathological diagnosis is the highly reliable method at present. Thus, in the absence of risk factors for a primary liver tumor or metastatic tumor in middle-aged and elderly women, the possibility of pseudolymphoma should be considered to avoid extensive treatments.

Lymphoid hyperplasia with a polyp form of the gallbladder macroscopically mimicking carcinoma

Lymphoid hyperplasia is a type of tumor-like hyperplasia of lymphoid tissue. There have been few reports on lymphoid hyperplasia of the gallbladder. Here, we report a case of lymphoid hyperplasia with a polyp form of the gallbladder macroscopically mimicking carcinoma. Liver dysfunction was diagnosed in a 75-year-old woman who presented with a gallbladder mass measuring 20 mm during an annual health checkup. Antibody tests for infectious diseases were positive for anti-HBs and anti-HBc antibodies. Accordingly, a laparoscopic cholecystectomy was performed. Macroscopically, the mass was a papillary/sessile tumor (29 × 25 mm) located in the fundus of the gallbladder. Histologically, the tumor was accompanied by an erosion on a portion of the surface layer, while the remaining epithelium showed regenerative changes and mild hyperplasia. No atypia was observed in the constituent epithelium. Hyperplasia of the polarized lymphoid follicles was observed in the interstitium, and tingible body macrophages were scattered in the germinal center. Immuno-histologically, the germinal center showed CD20 positivity, weak CD10 positivity, Bcl-2 negativity, and a high Ki-67 index (MIB-1). These findings suggested that the proliferating lymphoid follicles were reactive rather than neoplastic. Therefore, we diagnosed the patient with lymphoid hyperplasia of the gallbladder and chronic cholecystitis.

OUP accepted manuscript

Reactive lymphoid hyperplasia (RLH) of the liver is an extremely rare benign lesion, which is often misdiagnosed as a malignant liver tumour. We present the case of a 69-year-old man with an incidental liver tumour revealed on the ultrasonography of the kidney-urinary bladder system for benign prostatic hyperplasia. Hepatocyte-specific contrast (gadoxetate disodium) magnetic resonance imaging revealed a round 6-mm lesion, which was hypointense on T1-weighted images, slightly hyperintense on T2-weighted images and highly intense on diffusion-weighted images. Other findings included arterial hyperintensity, venous and delayed hypointensity and a defect in liver segment 6. The patient was diagnosed with hepatocellular carcinoma; laparoscopic partial hepatectomy was performed. Intraoperatively, a 7-mm greyish white solid nodule was observed. In conclusion, it may be difficult to distinguish RLH from other malignant liver tumours. However, it should be considered as a differential diagnosis for small liver lesions in young, female patients without liver cirrhosis.

Imaging Manifestations of Intrahepatic Reactive Lymphoid Hyperplasia: A Case Report and Literature Review

Reactive lymphoid hyperplasia (RLH) of the liver is a rare benign disease. This article describes a 77-year-old female patient with RLH of the liver. The patient was admitted to the hospital due to atrial fibrillation. A liver tumor was incidentally found during abdominal enhanced CT. Further magnetic resonance imaging (MRI) and PET/CT showed four lesions in the liver. The imaging findings suggested hepatocellular carcinoma (HCC), but it was not consistent that the patient had no history of liver cirrhosis and hepatitis, and a variety of tumor markers were within the normal range. The largest lesion was surgically removed and microscopically diagnosed as RLH of the liver. The pathology included a large number of reactive hyperplastic lymphoid follicles. Immunohistochemical examination showed that the infiltrating lymphocytes were polyclonal. The authors believe that the perinodular enhancement on MRI, the obvious limitation of diffusion on DWI, the insignificant increase of SUVmax on PET-CT delayed phase, and the support of clinical data can help distinguish liver RLH from lymphoma and HCC.

Diffusion-weighted imaging might be useful for reactive lymphoid hyperplasia diagnosis of the liver: A case report

BACKGROUND

Reactive lymphoid hyperplasia (RLH) of the liver is a rare liver lesion. It is considered difficult to differentiate radiologically from hepatocellular carcinoma, metastatic liver tumor and other pathologies.

CASE SUMMARY

A 54-year-old woman presented to our hospital with RLH of the liver. The patient had a diagnosis of metastatic carcinoma of the liver from an unknown origin and subsequently underwent partial hepatectomy. However, histopathological analysis revealed RLH. The lesion showed perinodular enhancement in the arterial phase on contrast-enhanced computed tomography and magnetic resonance imaging. On diffusion-weighted imaging (DWI), we encountered linear hyperintensity along the portal tract consecutive to the liver lesion, which is a new characteristic radiologic finding. This finding corresponded to the lymphoid cell infiltration of the portal tract. Furthermore, there was strongly restricted diffusion on the apparent diffusion coefficient map. We used these characteristic radiologic findings to diagnose the lesion as a lymphoproliferative disease.

CONCLUSION

The linear hyperintensity consecutive to the liver lesion on DWI provided additional valuable diagnostic information.

A case of reactive lymphoid hyperplasia of the liver in a patient with autoimmune hepatitis

Background

Reactive lymphoid hyperplasia (RLH) of the liver is a benign disorder. It is usually observed in the skin, orbit, thyroid, lung, breast, or gastrointestinal tract, but rarely in the liver. Since the first report of RLH of the liver in 1981, only 75 cases have been described in the past literature. Herein, we report a case of RLH of the liver in a patient with autoimmune hepatitis (AIH), which was misdiagnosed as hepatocellular carcinoma (HCC) preoperatively and resected laparoscopically.

Case presentation

A 43-year-old Japanese woman with autoimmune hepatitis was followed up for 5 years. During her medical checkup, a hypoechoic nodule in segment 6 of the liver was detected. The nodule had been gradually increasing in size for 4 years. Abdominal ultrasound (US) revealed a round, hypoechoic nodule, 12 mm in diameter. Contrast-enhanced computed tomography (CT) demonstrated that the nodule was slightly enhanced in the arterial dominant phase, followed by perinodular enhancement in the portal and late phases. A magnetic resonance imaging (MRI) scan showed low signal intensity on the T1-weighted image (T1WI) and slightly high signal intensity on the T2-weighted image (T2WI). The findings of the Gd-EOB-DTPA-enhanced MRI were similar to those of contrast-enhanced CT. Tumor markers were all within the normal range. The preoperative diagnosis was HCC and a laparoscopic right posterior sectionectomy was performed. Pathological examination revealed that the nodular lesion was infiltrated by small lymphocytes and plasma cells, and germinal centers were present. Immunohistochemistry was positive for B cell and T cell markers, indicating polyclonality. The final diagnosis was RLH of the liver.

Conclusions

The pathogenesis of RLH of the liver remains unknown, and a definitive diagnosis based on imaging findings is extremely difficult. If a small, solitary nodule is found in female patients with AIH, the possibility of RLH of the liver should be considered.

A case of hepatic pseudolymphoma in a patient with primary biliary cirrhosis

Hepatic pseudolymphoma is a very rare benign reactive lymphoid hyperplasia associated with autoimmunity and chronic inflammatory liver diseases such as primary biliary cirrhosis and may mimic hepatocellular carcinoma. This diagnosis should be suspected in female with a suspicious single tumor. Close monitoring is needed in view of its premalignant nature.

Reactive lymphoid hyperplasia of the liver: A case report

RATIONALE

Reactive lymphoid hyperplasia (RLH) of the liver is an uncommon benign lesion. It is usually difficult to differentiate from hepatocellular carcinoma (HCC), peripheral-type cholangiocellular carcinoma (CCC), combined HCC-CCC, and liver metastases. On account of its rarity and controversial issues, we report a case report and review the literature to discuss its clinical features, treatments, radiological, and immunohistochemical characteristics.

PATIENT CONCERNS

A 54-year-old woman had a history of primary biliary cirrhosis and chronic cholecystitis. She complained of finding a lesion in the right liver during her last medical check-up by abdominal B type ultrasound. The Contrast-enhanced computed tomography revealed a circular and low-density lesion in the right posterior lobe of the liver, approximately 22.0 × 18.7 mm in size. On magnetic resonance imaging, the lesion showed low-signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Laboratory test results were almost normal.

DIAGNOSIS

After the postoperative pathological and immunohistochemical examination, the patient was finally diagnosed as having RLH.

INTERVENTIONS

The patient received right posterior lobe hepatectomy and cholecystectomy.

OUTCOMES

The patient was discharged 11 days after surgery. No evidence of recurrence was noted 1 year after the surgery.

LESSONS

Although RLH of the liver is rare, it is necessary to be considered in a liver lesion, especially in female patients. This case report may advance the understanding of RLH of the liver and reduce the number of mistakenly diagnosed patients.

Prognostic value of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography in primary hepatic mucosa-associated lymphoid tissue lymphoma: A case report and review of the literature

INTRODUCTION

Primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma is extremely rare and we herein report a case of a patient suffering from primary hepatic MALT lymphoma with concomitant hepatitis B virus infection.

DIAGNOSTIC MODALITIES AND OUTCOME

Double masses were found in a 59-year-old Chinese female patient. We reported the laboratory results, computed tomography (CT) and fluorine-18-fluorodeoxyglucose (F-FDG) positron emission tomography (PET)/CT images among other findings. As far as we know, only 9 cases have been reported till now using F-FDG PET/CT imaging. Our patient's lesions were found to conform to standard uptake values of FDG.

CONCLUSION

It indicates that hepatic MALT lymphoma can be studied with F-FDG PET/CT like other F-FDG-avid lymphomas. It was also noted that delayed-time-point FDG PET imaging may further improve the detection of the MALT lymphoma in liver. Although the patient in this case refused further treatment, potential management options, including rituximab, which is also discussed in this review.

Pseudolymphoma of the liver: a case report and literature review

Pseudolymphoma is a benign lymphocytic tumor-like lesion, and its occurrence in the liver is rare. Here, we report the case of a 78-year-old woman with pseudolymphoma of the liver. She had a history of tremors for several years. Therefore, she underwent computed tomography (CT) for screening, and liver tumors were incidentally identified. She did not have any history of liver disease. Liver function test results and tumor marker levels were all within normal limits, and viral markers for hepatitis were negative. Contrast-enhanced CT revealed four nodules measuring up to 13 mm in diameter with ring enhancement in both lobes of the liver. On magnetic resonance imaging, the lesions showed slightly high intensity on T2-weighted images and high intensity on diffusion-weighted images. Because of atypical imaging findings, the tumors could not be definitively diagnosed. Therefore, we performed laparoscopic limited resection of segments 2, 3, 4, and 8 of the liver. The final pathological diagnosis was pseudolymphoma of the liver. The patient has had no signs of recurrence for 6 months after the surgery. Although pseudolymphoma of the liver is rare, it is necessary to consider it in the differential diagnosis of a liver tumor.

Hepatic nodular lymphoid lesion with increased IgG4-positive plasma cells associated with primary biliary cirrhosis: a report of two cases

The nodular lymphoid lesion of the liver known as reactive lymphoid hyperplasia or pseudolymphoma is rare and its pathogenesis is unknown. We report two cases of nodular lymphoid lesions of the liver with numerous IgG4-positive plasma cells in patients with primary biliary cirrhosis. Histologically, in both cases, the lesion showed a dense lymphoplasmacytic infiltrate with lymphoid follicles and granulomas. Fibrous tissue was scarce and without a storiform pattern. Obliterative phlebitis was not identified. The IgG4+ plasma cell counts were 82 and 76 per high power field, with an IgG4/IgG ratio of 75 and 64 %, respectively, which qualifies the lesions according to the diagnostic criteria for IgG4-related disease as « probable histological feature of IgG4-related disease ». There were no rearrangements of immunoglobulin heavy-chain genes and plasma cells had a polytypic pattern of kappa and lambda light-chain expression. The non-tumor liver showed primary biliary cirrhosis with destructive cholangitis without IgG4 plasma cells. In both cases, IgG4-related disease was not found in other organs neither at the time of diagnosis nor 3 years later. Serum IgG4 levels normalized after local ablation of the lesions. It seems unlikely that these lesions are a manifestation of IgG4-related disease. However, because the pathogenesis of both nodular lymphoid lesions and IgG4-related disease remains unclear, further studies are needed to elucidate a potential link between nodular lymphoid lesions of the liver and an increased number of IgG4 plasma cells. More definite conclusions will be possible when the pathogenesis of IgG4-related disease has been clarified.

Reactive lymphoid hyperplasia of the liver: Perinodular enhancement on contrast-enhanced computed tomography and magnetic resonance imaging

We report the case of a 69-year-old woman with reactive lymphoid hyperplasia (RLH) of the liver. She underwent partial hepatectomy under a preoperative diagnosis of hepatocellular carcinoma; however, histopathological analysis revealed RLH. The liver nodule showed the imaging feature of perinodular enhancement in the arterial dominant phase on contrast-enhanced computed tomography and magnetic resonance imaging, which could be a useful clue for identifying RLH in the liver. Histologically, the perinodular enhancement was compatible with prominent sinusoidal dilatation surrounding the liver nodule.

Reactive lymphoid hyperplasia of the liver mimicking hepatocellular carcinoma: incidental finding of two cases

Reactive lymphoid hyperplasia is a rare disease that forms a mass-like lesion and is characterized by the proliferation of non-neoplastic, polyclonal lymphocytes forming follicles. We recently encountered 2 cases of reactive lymphoid hyperplasia of liver, both of which were asymptomatic and mimicked hepatocellular carcinoma by various imaging modalities. Based on the clinical impression of hepatocellular carcinoma, surgical resections were performed. Microscopic findings revealed that both lesions consisted of an aggregation of lymphocytes consisting of predominantly B-cells, with multiple lymphoid follicles positive for CD10 and negative for bcl-2, consistent with the diagnosis of reactive lymphoid hyperplasia. Polyclonality of both lesions was further confirmed by B cell receptor gene rearrangement study. The incidence of reactive lymphoid hyperplasia in the liver is exceedingly rare, and it is difficult to differentiate such lesions from hepatic malignancies based upon clinical grounds. The clinicopathological findings and literature review of this report may be helpful to improve the clinical decision-making.

Reactive lymphoid hyperplasia of the liver requires differential diagnosis of hepatocellular carcinoma

Reactive lymphoid hyperplasia (RLH) of the liver is a rare and benign nodular lesion. It remains difficult to distinguish RLH from hepatocellular carcinoma (HCC) despite recent advances in imaging modalities. We report five cases of RLH that required differential diagnosis of HCC preoperatively. These cases all occurred in middle-aged women and were associated with autoimmune disease in 40% (2/5). The diameter of the nodule was less than 2 cm in all five of our cases. Four cases had a preoperative diagnosis of HCC. When a liver nodule is found in middle-aged women with an autoimmune disease, the possibility of RLH should be considered.

Hepatic pseudolymphoma: imaging-pathologic correlation with special reference to hemodynamic analysis

OBJECTIVES

To clarify radiological findings and hemodynamic characteristics of hepatic pseudolymphoma, as compared with the histopathological findings.

METHODS

Radiological findings of ten histopathologically confirmed hepatic pseudolymphomas in seven patients were examined using US, CT, and MRI. Six patients also underwent angiography-assisted CT, including CT during arterial portography (CTAP) and CT during hepatic arteriography (CTHA) to analyze hemodynamics.

RESULTS

The nodules were depicted as hypoechoic on US, hypodense on precontrast CT, hypointense on T1-weighted images, and hyperintense on T2-weighted images. On contrast-enhanced CT/MRI, they showed various degrees of enhancement, and sometimes, perinodular enhancement was observed at the arterial dominant and/or equilibrium phase. On CTAP, the nodules showed portal perfusion defects, including some in the perinodular liver parenchyma. On CTHA, irregular bordered enhancement was observed in perinodular liver parenchyma on early phase, and continued until delayed phase. Some nodules had preserved intra-tumoral portal tracts. Histopathologically, the nodules consisted of marked lymphoid cells. In perinodular liver parenchyma, stenosis or disappearance of portal venules, caused by lymphoid cell infiltration in the portal tracts, was observed.

CONCLUSIONS

Hepatic pseudolymphoma showed some characteristic radiological findings including hemodynamics on CT, MRI, and angiography-assisted CT. These findings are useful in the differentiation from hepatocellular carcinoma and other tumors.

Pseudolymphoma of the liver: Report of a case and review of the literature

We report a case of pseudolymphoma of the liver in a 49-year-old woman without an underlying disease except for liver hemangioma. A 20-mm nodule was incidentally found in segment 2 of the liver by abdominal ultrasonography during a regular follow-up of the hepatic hemangioma. After a series of radiological examinations, a left lateral sectionectomy was performed because malignant hepatic tumor could not be excluded. The patient was discharged uneventfully 7 days after the operation. The pathology examination revealed a pseudolymphoma. No recurrence of the tumor was found 5½ years after the operation. To the best of our knowledge, only 46 cases of pseudolymphoma of the liver have been reported to date. A review of the literature showed that pseudolymphomas occur predominantly in females (89.4%), usually occur as a single tumor (80.4%), are no more than 20 mm in size (90.6%), and are frequently associated with either autoimmune disease or chronic liver disease. Because an accurate diagnosis is difficult to establish, vigilant follow-up is indicated, and surgical intervention is the choice of treatment once the suspiciousness of malignancy has been raised.

Reactive lymphoid hyperplasia of the liver and pancreas. A report of two cases and a comprehensive review of the literature

BACKGROUND

Reactive lymphoid hyperplasia (RLH) is a rare non-neoplastic extranodal pathology with exceedingly rare occurrence in the liver and pancreas. We present two cases of hepatic RLH, one which had coinciding pancreatic involvement. To the best of our knowledge, concomitant hepatic and pancreatic RLH has not been previously reported. We also present a comprehensive review of the literature on hepatic and pancreatic RLH.

METHODS

An extensive literature search for all published reports on hepatic or pancreatic RLH was conducted. Data on clinical, radiographic and histopathological features were extracted in addition to therapeutic options and outcomes.

RESULTS

Forty-two hepatic and three pancreatic cases of RLH were described in the literature. The mean age of hepatic cases was 58 years, with a male-to-female ratio of above 1:7. Almost 25% of cases were associated with internal malignancy. Four hepatic cases were managed through active observation. The remainder (84%) underwent surgical resection. Due to their small number, no meaningful analysis could be made on the pancreatic cases. No recurrences were identified in any of the reported cases.

CONCLUSION

RLH should be considered in the diagnosis of hepatic nodules where biopsies fail to demonstrate malignant cells. Confirmed RLH lesions should be managed by active observation. Investigation and treatment of any potential source of lymphoid reactivity should be undertaken. More reports on pancreatic RLH need to be studied prior to drawing any useful recommendations on its management.

Reactive lymphoid hyperplasia of the liver: a clinicopathological study of 7 cases

Background. Reactive lymphoid hyperplasia (RLH) of the liver is a benign focal liver mass that may mimic a malignant liver tumor. Although rarely encountered in clinical practice, it often poses diagnostic and management dilemmas. Methods. Cases diagnosed as hepatic RLH between January 1996 and June 2011 were investigated in a retrospective study. Clinicopathological features as well as follow-up information of the cases were studied. Results. A total of seven cases of hepatic RLH were investigated, with a median age of 46 years (range: 33–76 years). Hepatic RLH was accompanied by concomitant diseases in some patients. The average size of hepatic lesions of our cases was 45 mm (range: 15–105 mm). All of the cases were not accurately diagnosed until confirmed by pathological findings, and surgical resections were performed for all. Postoperative course was uneventful for all of the patients during followup. Conclusions. RLH of the liver is a rare benign disease with a female predilection of unknown etiology. It is very difficult to correctly diagnose this disease without pathological results. Subtle differences on radiological findings of it may be helpful for differential diagnosis from other diseases. Curative resection of the lesion is suggested for the treatment of this disease.

Lymphoid hyperplasia detected as a single mass in the gallbladder: report of a case

We herein report a case of lymphoid hyperplasia of the gallbladder that showed unique images on computed tomography and ultrasonography. A 42-year-old female was referred to our hospital for evaluation and treatment of a gallbladder tumor. Ultrasonography and computed tomography showed a mass in the wall of the gallbladder neck, without typical findings of benign or malignant tumors. The serum levels of tumor markers, such as carcinoembryonic antigen, carbohydrate antigen 19-9, alpha-fetoprotein, and cytokeratin 19 fragment, were all within normal limits. Laparoscopic cholecystectomy was therefore performed. There were no stones in the gallbladder. Macroscopically, the submural tumor had a clear border without a capsule and a cystic portion. Its cut surface was grayish white. Microscopically, many lymph follicles with germinal centers were recognized in the subserosal layer. The lymphocytes were morphologically normal. We diagnosed lymphoid hyperplasia with chronic cholecystitis. Lymphoid hyperplasia of the gallbladder is extremely rare.

Multinodular pseudolymphoma of the liver: computed tomography and magnetic resonance imaging findings

A 60-year-old woman who had had a history of renal cell carcinoma with intraperitoneal recurrence presented with multiple liver masses. Computed tomography demonstrated multiple enhancing lesions in the both lobes of the liver, and there was an apparent small vessel coursing within one of the lesions. On magnetic resonance imaging, masses showed slight T1 and T2 prolongation, and restricted diffusion: On the hepatobiliary phase of liver-specific contrast agent enhancement, lesions were shown as low signal intensity of varying degree. Liver metastases from renal cell carcinoma were suspected, and partial hepatectomy was performed for the superficially located nodules to make a definitive diagnosis. The final pathological diagnosis was reactive lymphoid hyperplasia or pseudolymphoma of the liver.

Imaging findings of localized lymphoid hyperplasia of the pancreas: a case report

We report here on a case of localized lymphoid hyperplasia of the pancreas in a 70-year-old man which manifested as double lesions (uncinate process and tail) in the organ. The lesions were incidentally detected as hypoechoic lesions on ultrasonography and they appeared as delayed enhancing lesions on the contrast-enhanced dynamic CT and MRI. Total pancreatectomy was performed, because malignant tumor could not be excluded according to the preoperative imaging studies and the endoscopic ultrasound-guided biopsy failed. Pathology revealed localized lymphoid hyperplasia. The patient had an uneventful postoperative course. He has been alive for 18 months after surgery.

MR imaging of reactive lymphoid hyperplasia of the liver

INTRODUCTION

Reactive lymphoid hyperplasia, also known as pseudolymphoma or nodular lymphoid lesion of the liver, is a rare benign lesion. It is mainly detected in the lung, stomach, small intestine, orbit, pancreas, skin, and breast. It remains difficult to distinguish reactive lymphoid hyperplasia from malignant disease clinically when it develops in the liver.

CASE REPORT

We have recently encountered a patient with liver reactive lymphoid hyperplasia who had undergone colon cancer surgery.

CONCLUSION

Preoperative MR imaging showed some useful findings indicating reactive lymphoid hyperplasia.

Reactive lymphoid hyperplasia of liver mimicking late ovarian cancer recurrence: case report and literature review

Reactive lymphoid hyperplasia (RLH) is a rare, benign, lymphocytic tumour-like lesion reported in various organs. It has been previously identified in 18 cases in the English-language literature, but only 5 of them were related to oncological disease. No previous cases have been described of RLH occurring in ovarian cancer patients. We describe a case of hepatic RLH which developed in a patient treated for ovarian cancer 11 years previously. Radiological features on computed tomography (CT) scan and PET-CT (positron emission tomography-computed tomography) were strongly suggestive of oncological disease, in contrast to magnetic resonance imaging (MRI); the volume increment of the nodular lesion and the rise in carbohydrate antigen 125 corroborated the hypothesis of malignancy. The patient was subjected to resection of the 7th segment of the liver and the final histological report showed RLH. RLH should be considered in the presence of hepatic lesions in suspected ovarian cancer recurrence. Imaging techniques should be thoroughly investigated to exclude tumor recurrence promptly, in order to avoid unnecessary surgery.

An operative case of hepatic pseudolymphoma difficult to differentiate from primary hepatic marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue

Hepatic pseudolymphoma (HPL) and primary hepatic marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are rare diseases and the differential diagnosis between these two entities is sometimes difficult. We herein report a 56-year-old Japanese woman who was pointed out to have a space occupying lesion in the left lateral segment of the liver. Hepatitis viral-associated antigen/antibody was negative and liver function tests including lactic dehydrogenase, peripheral blood count, tumor markers and soluble interleukin-2 receptor were all within normal limit. Imaging study using computed tomography and magnetic resonance imaging were not typical for hepatocellular carcinoma, cholangiocarcinoma, or other metastatic cancer. Fluorodeoxyglucose-positron emission tomography examination integrated with computed tomography scanning showed high standardized uptake value in the solitary lesion in the liver. Under a diagnosis of primary liver neoplasm, laparoscopic-assisted lateral segmentectomy was performed. Liver tumor of maximal 1.0 cm in diameter was consisted of aggregation of lymphocytes of predominantly B-cell, containing multiple lymphocyte follicles positive for CD10 and bcl-2, consistent with a diagnosis of HPL rather than MALT lymphoma, although a definitive differentiation was pending. The background liver showed non-alcoholic fatty liver disease/early non-alcoholic steatohepatitis. The patient is currently doing well with no sign of relapse 13 months after the surgery. Since the accurate diagnosis is difficult, laparoscopic approach would provide a reasonable procedure of diagnostic and therapeutic advantage with minimal invasiveness for patients. Considering that the real nature of this entity remains unclear, vigilant follow-up of patient is essential.

Hepatic reactive lymphoid hyperplasia in a patient with primary biliary cirrhosis

Reactive lymphoid hyperplasia (RLH) of the liver is an extremely rare lesion characterized by the proliferation of non-neoplastic lymphocytes forming follicles. Hepatic RLH is known to be associated with gastrointestinal carcinoma and autoimmune diseases including primary biliary cirrhosis (PBC). We report a case of hepatic RLH in a patient with PBC and gastric cancer. A 68 year old Japanese woman with a 10 year history of liver enzyme abnormality was admitted. Laboratory testing revealed that her anti-mitochondrial antibody was markedly elevated. Five mo after the diagnosis of PBC, she was found to have gastric cancer. Abdominal computed tomography disclosed a liver nodule in S8, suggesting metastatic gastric carcinoma. Histopathologically, the resected liver lesion comprised of a nodular proliferation of small lymphocytes with lymphoid follicles. This is the first reported case of hepatic RLH in a patient with both PBC and gastric cancer. Pre-operative diagnosis of hepatic RLH by clinical imaging is extremely difficult. Therefore, a needle biopsy could be useful to make a diagnosis of hepatic RLH, especially to differentiate from metastatic gastrointestinal carcinoma.

Hepatic pseudolymphoma: a clinicopathological study of five cases and review of the literature

Hepatic pseudolymphoma is a rare and controversial condition, the clinicopathological characteristics of which have not been well documented. In this study, we retrospectively examined clinical and pathological features of five patients (two males and three females, 40-81 years old) with hepatic pseudolymphoma. Two patients had multiple lesions (two lesions each). Three patients had histories of chronic liver disorders, including primary biliary cirrhosis, nonalcoholic steatohepatitis, and chronic viral hepatitis B. Tumor sizes ranged from 0.5 to 5.5 cm in diameter (average, 2.1 cm). Histologically, hepatic pseudolymphoma consisted of tumorous infiltrates of mature lymphocytes with multiple lymph follicles or clusters of epithelioid histiocytes. Lymphocytes characteristically extended into nearby portal tracts. 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. Two patients were diagnosed by needle biopsy. Interestingly, their nodules spontaneously diminished in size without any treatment. Malignant transformation was not observed in any cases during the follow-up periods. In conclusion, this study revealed that hepatic pseudolymphoma had benign behavior. The diagnosis of hepatic pseudolymphoma can be challenging especially with biopsied specimens, but could be aided by a characteristic growth pattern, in situ hybridization, analyses of gene rearrangements, or a follow-up based on images.

Pseudolymphoma of the liver associated with primary biliary cirrhosis: a case report and review of literature

We report a case of two pseudolymphomas of the liver in a 63-year-old Japanese woman with primary biliary cirrhosis. One of the lesions was found incidentally during a medical examination, presenting as a 10 mm hypodense nodule that revealed hyperdensity in the early phase and hypodensity in the late phase in computed tomography (CT) after injection of contrast medium. Retrospectively, the 10 mm nodule had first been discovered as a 4 mm nodule during CT 4 years previously. Superparamagnetic iron oxide-enhanced MRI revealed another 4 mm hyperintense nodule in segment 6 in addition to the 10 mm hyperintense nodule in segment 7. CT during arterial portography revealed two hypointense nodules. Findings with other imaging modalities such as ultrasonography, magnetic resonance imaging, and hepatic angiography were consistent with hepatocellular carcinoma. A right posterior segmentectomy was performed, and the lesions were microscopically diagnosed as pseudolymphoma. To the best of our knowledge, only 31 other cases of this disease have ever been reported, with a highly asymmetrical male:female ratio of 1:9.7. Although we could find only one case of transformation of hepatic pseudolymphoma into lymphoma in the liver, the exact nature of development from benign pseudolymphoma to malignant lymphoma is still not fully understood and cases of hepatic lymphoma need to be followed carefully.

Hypointense hepatic lesions depicted on gadobenate dimeglumine-enhanced three-hour delayed hepatobiliary-phase MR imaging: differentiation between benignancy and malignancy

Gadobenate dimeglumine-enhanced magnetic resonance (MR) imaging simultaneously provides both morphological and functional information by the acquisition of dynamic and hepatobiliary-phase imaging. Focal lesions with no functioning hepatocytes, where hepatobiliary metabolism is blocked or inhibited, are generally unable to uptake and excrete gadobenate dimeglumine into the bile. Such lesions are typically malignant and usually appear hypointense as compared to the normal liver parenchyma as seen on hepatobiliary-phase imaging. However, various benign hepatic lesions may also be hypointense due to (a) the presence of no functioning hepatocytes, (b) damage to the functioning hepatocytes or (c) impairment of biliary function as depicted on hepatobiliary-phase imaging. All of these imaging features may result in recognition of the benign hepatic lesions as hepatic malignancies. As depicted on three-hour delayed hepatobiliary-phase imaging, peripheral iso/hyperintensity due to fibrotic tissue compared to the hypointense center with a fuzzy margin may be a clue for the presence of a benign hepatic lesion. In contrast, peripheral hypointensity due to rich tumoral cellularity compared to the center with a clear margin may favor an indication of the presence of a malignant hepatic lesion.

Computed tomography and magnetic resonance imaging features of lesions of the renal medulla and sinus

The kidneys can harbor a wide variety of lesions, many of which can be visualized by computed tomography and magnetic resonance imaging. In this article, the pertinent renal anatomic relationships as well as the histologic composition and function of the renal medulla and sinus are reviewed. Additionally, computed tomography and magnetic resonance imaging features of renal sinus and medullary lesions in adult patients are presented. This article reviews the salient imaging features of various malignant, benign neoplastic, and nonneoplastic lesions of the sinus and medulla.

Histiocyte-rich reactive lymphoid hyperplasia of the liver: unusual morphologic features

Reactive lymphoid hyperplasia (RLH) of the liver is a rare entity and has also been termed nodular lymphoid lesion or pseudolymphoma of the liver. We report a case of hepatic RLH exhibiting unusual histiocyte-rich histologic features in a 47-yr-old woman in conjunction with a renal cell carcinoma. A follow-up computed tomography scan was done 14 months after a right radical nephrectomy for renal cell carcinoma revealed a nodular lesion in segment 5 of the liver. The lesion was interpreted as metastatic renal cell carcinoma or hepatocellular carcinoma based on the history of the patient and radiologic findings. Wedge resection of segment 5 was done with sufficient distance from the mass. Microscopically, the lesion was composed predominantly of peculiar histiocytic proliferation and was characterized by lymphoid aggregates forming a lymphoid follicle with germinal centers. The present case and prior cases reported in the literature suggest that RLH of the liver appear to be a heterogenous group of reactive inflammatory lesions that are often associated with autoimmune disease or malignant tumors.