2376 Diffuse Large B-Cell Lymphoma Presenting With Typical Features of HCC on Liver Imaging: A Diagnostic Conundrum

Abstract

INTRODUCTION: Hepatocellular carcinoma (HCC) is the most common primary liver malignancy. HCC can be solely diagnosed on cross-sectional imaging (CT or MRI) if a lesion meets the diagnostic criteria according to the Liver Imaging Reporting and Data System (LI-RADS), which has above 90% specificity. HCC commonly metastasizes to lungs, regional lymph nodes, kidney, bone marrow and adrenals but metastases to the spleen are rare. We present a case of liver masses with typical HCC characteristics on liver MRI which was ultimately proven to be diffuse large B-cell lymphoma (DLBCL) on liver biopsy. CASE DESCRIPTION/METHODS: 38-year-old Vietnamese male with no past medical history was admitted with significant weight loss, fatigue and abdominal discomfort. He did not have a history of high risk behaviors or recent foreign travel. Physical exam revealed hepatomegaly. On labs, CBC was normal, T-bili 0.7, Alk Phos 147, AST 89, ALT 50, Albumin 3 g/dL, INR 1.1, creatinine 0.7. HBV serology was positive for HBsAg, anti-HBc and anti-HBe and was negative for HBeAg. HBV DNA was 497 IU/ml. HIV, HCV and HDV serology were negative. CT abdomen showed numerous liver lesions, largest of which was 10.4 cm and a single 8.1 cm splenic lesion. MRI showed several large, rounded and well-circumscribed liver lesions demonstrating arterial hyperenhancement, washout and pseudocapsule consistent with diagnosis of HCC (LI-RADS 5). MRI confirmed a single lesion on spleen (Figure 1), suspicious for metastasis. Tumor markers (AFP, CEA, CA 19-9) were within normal range. Lactate dehydrogenase (LDH) was 1200. Given elevated LDH and a spleen lesion, liver biopsy was done which showed high grade DLBCL (Figure 2). Systemic staging tests did not reveal any other tumor sites. Patient was started on tenofovir and chemotherapy with excellent response (Figure 3). DISCUSSION: Liver biopsy is rarely required to diagnose HCC if certain diagnostic criteria are met on cross sectional imaging, even without significantly elevated AFP. Extranodal lymphoma with liver and spleen involvement can present with lab and imaging abnormalities which can mimic HCC, as in our case. Markedly elevated LDH and spleen lesion raised suspicion for a different diagnosis. Undiagnosed or untreated advanced DLBCL can limit survival to a few months while hepatic involvement can also cause liver failure. In conclusion, a biopsy should be considered for liver lesions diagnosed as HCC on cross sectional imaging when atypical features, in our case elevated LDH and spleen lesion, are present.