CASE 13970 Published on 26.09.2016

Diffuse large B-cell lymphoma with bilateral renal involvement

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

Tyler Brown BS1, Clint Walters MD2, Darko Pucar MD PhD2, and Kandace Klein DO2

1Medical College of Georgia, School of Medicine, Augusta University
2 Medical College of Georgia, Augusta University, Department of Radiology & Imaging

1120 15th Street,
BA-1411 30912 Augusta,
United States of America;
Email:dpucar@augusta.edu
Patient

50 years, male

Categories
Area of Interest Abdomen, Liver, Kidney ; Imaging Technique Ultrasound, CT, MR, PET, PET-CT
Clinical History
A 50-year-old male patient presented with a 3-week history of worsening epigastric pain, abdominal distention and constipation. The patient denied fever, chills, nausea, vomiting, or changes in weight. Laboratory results revealed anaemia and elevated liver enzymes.
Imaging Findings
Ultrasound demonstrated a large heterogeneous liver lesion which prompted further evaluation (Fig. 1). Computed tomography (CT) showed a 12 cm liver mass with focal hyperdensity corresponding to haemorrhage (Fig. 2). Magnetic resonance imaging (MRI) revealed rounded areas of T2 hypointensity throughout the left renal parenchyma and involving the upper pole of the right kidney concerning for metastatic disease (Fig. 3, a-c). Tissue sampling of the liver mass confirmed diffuse large B-cell lymphoma (DLBCL) without bone marrow involvement. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT demonstrated intensely increased uptake within the liver mass, upper pole of the right kidney, and throughout the left renal parenchyma (Fig. 4, a-e). Following completion of the initial treatment regimen, 18F-FDG PET-CT revealed a complete metabolic with normal urinary excretion of FDG in the renal collecting systems (Fig. 5, a-e).
Discussion
DLBCL is the most common form of non-Hodgkin’s lymphoma (NHL) accounting for 40% of newly diagnosed cases with the majority of individuals older than 60 years of age [1]. Approximately 33% of patients with DLBCL present with extra-nodal involvement, with the majority of these cases limited to the gastrointestinal tract; renal involvement is rare [2]. Current treatment regimens favour an aggressive approach and include a combination of the monoclonal antibody rituximab with multiple chemotherapy agents (cyclophosphamide, doxorubicin, vincristine and prednisolone) (R-CHOP) [3].

Approximately 2% of patients have renal involvement at the time of diagnosis with half of these cases being bilateral [4]. The overall 5-year survival rate in patients with renal involvement following treatment with R-CHOP is 44% [4]. Therefore, imaging has become an essential component of the workup and staging of patients presenting with DLBCL.

Initial evaluation of a suspected abdominal mass includes ultrasound as it is a quick, cost effective modality that does not utilize ionizing radiation. However, the imaging findings may be nonspecific. Songraphically, DLBCL presents as a large hypoechoic lesion with respect to the surrounding parenchyma that can demonstrate internal heterogeneity [5]. Further workup can involve CT which would reveal a soft tissue attenuating mass with possible cystic lesions and focal areas of necrosis. Diffusion weighted (DW)-MRI provides better soft tissue differentiation and visualization of subtle abnormalities. Though DLBCL can be suspected on imaging, tissue sampling is still a mainstay for making a definitive diagnosis.

18F-FDG PET-CT is the most important imaging examination for staging and evaluating treatment response in patients with NHL. 18F-FDG is preferentially taken up by tumour cells, phosphorylated and trapped due to its inability to participate in glycolysis. The use of this modality for evaluating extra-nodal involvement has an overall sensitivity and specificity of 97% and 100%, respectively [6]. There has been some speculation on the use of DW-MRI with apparent diffusion coefficients for staging and evaluating treatment response due to the lack of ionizing radiation, but studies using this modality to evaluate treatment response in DLBCL are few and far between. However, the results have been promising [7].

In conclusion, DLBCL is the most common form of NHL and presents in older individuals. Imaging is vital in the diagnosis and management of extra-nodal involvement. Since DLBCL rarely presents with renal involvement, it is important to recognize subtle imaging abnormalities as they can impact patient care and therapy.
Differential Diagnosis List
Primary hepatic diffuse large B-cell lymphoma with bilateral renal involvement.
Other types of aggressive high-grade lymphoma
Metastatic disease
Final Diagnosis
Primary hepatic diffuse large B-cell lymphoma with bilateral renal involvement.
Case information
URL: https://www.eurorad.org/case/13970
DOI: 10.1594/EURORAD/CASE.13970
ISSN: 1563-4086