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

Reactive lymphoid hyperplasia of the liver: A case report featuring characteristic nodular and perinodular enhancement

A 53-year-old female with primary biliary cholangitis was referred for the evaluation of a hepatic nodule identified during routine imaging. Ultrasonography revealed a homogeneous, hypoechoic, 18 mm nodule in segment 3 of the liver. On dynamic CT and MRI, the nodule showed mild enhancement at the hepatic artery-dominant phase. On diffusion-weighted images, the nodule exhibited pronounced hyperintensity with accompanying wedge-shaped perinodular hyperintensity (comet and comet-tail appearance). The nodule showed a portal perfusion defect on CT during arterial portography, and mild enhancement on CT during hepatic arteriography (CTHA). A nodular and wedge-shaped perinodular enhancement (comet and comet-tail appearance) in the CTHA was also clearly observed. The nodule demonstrated abnormal FDG uptake on 18F-FDG-PET/CT. An excisional biopsy was performed for histopathological diagnosis, and the nodule was diagnosed as reactive lymphoid hyperplasia (RLH). Diagnosing hepatic RLH by imaging is challenging due to its imaging findings overlapping with those of various malignant tumors, especially the nodular type of lymphomas, making differentiation particularly difficult. However, radiologists should note the perinodular early enhancement and the perinodular hyperintensity on diffusion weighted images, which are thought to be key imaging findings of RLH, along with other characteristics such as a single, small, homogeneous nodule with mild early enhancement and marked restricted diffusion. We propose to name the nodular lesion with perinodular early enhancement/hyperintensity on diffusion weighted images as 'comet and comet-tail appearances'.

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.

Reactive lymphoid hyperplasia of the liver: A rare case report

BACKGROUND

Hepatic reactive lymphoid hyperplasia (RLH) is a rare benign lymphoproliferative lesion and a poorly understood disease. It is usually asymptomatic and incidental, but it is difficult to distinguish from hepatocellular carcinoma and metastatic liver tumor on imaging, and percutaneous biopsy is not sufficient to distinguish from low-grade malignant lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), making diagnosis difficult.

CASE SUMMARY

A 69-year-old woman came to our hospital for reexamination of pulmonary nodules followed by liver occupation. The lesions showed "wash-in and wash-out" on contrast-enhanced ultrasonography and magnetic resonance imaging. Enhanced magnetic resonance also showed annular envelope enhancement and limited diffusion on the ADC map during the delay period. Imaging revealed metastatic liver cancer, and the patient underwent a partial hepatectomy. However, the final histopathological diagnosis was RLH.

CONCLUSION

If small isolated nodules are found in the liver of middle-aged and elderly female patients with no risk factors for liver malignancy, when the enhanced imaging suggests "wash-in and wash-out", further focus should be placed on whether the enhanced imaging shows perinodular enhancement and whether the DWI shows limited diffusion in MRI, in order to emphasize the possibility of liver RLH diagnosis.

Hepatic reactive lymphoid hyperplasia-associated primary biliary cholangitis masquerading as a neoplastic liver lesion

Hepatic reactive lymphoid hyperplasia is an uncommon benign condition, often found incidentally as a solitary liver lesion. The chronic inflammatory reaction associated with autoimmune conditions and malignancies has been postulated as a possible aetiology. The diagnosis is challenging as it often mimics various malignancies radiologically and histologically, hence the diagnosis being made only after surgical resection. Lymphadenopathy is common with primary biliary cholangitis, though rarely reported with reactive lymphoid hyperplasia. We report a case of hepatic reactive lymphoid hyperplasia associated with portacaval lymphadenopathy in a patient with primary biliary cholangitis, diagnosed after surgical resection. We propose lesional biopsy be considered in patients with primary biliary cholangitis found to have a solitary lesion with supporting low-risk clinical and radiological features.