Hepatocellular Carcinoma Arising in a Huge Hepatocellular Adenoma with Bone Marrow Metaplasia

Abstract

Hepatocellular adenoma (HCA) is the most common type of benign liver tumor, and its major complication is malignant transformation to hepatocellular carcinoma (HCC). Here, we report a case of HCC arising in HCA with bone marrow metaplasia in a 24-year-old Korean woman who presented with abdominal discomfort. A huge liver mass was found on abdominal ultrasonography. She underwent surgical hepatic resection, and the resected specimen was entirely involved by a 20-cm-sized tumor. Histological review revealed a well differentiated HCC arising from inflammatory HCA with β-catenin nuclear positivity and bone marrow metaplasia that contained hematopoietic cells. This case was unique because malignant transformation, inflammatory type HCA, β-catenin nuclear staining, and bone marrow metaplasia were simultaneously observed. Additionally, it should be noted that a large HCA with β-catenin activation can undergo malignant transformation and should be surgically resected in a timely manner.

Bilateral Diffuse Nodular Pulmonary Ossification Mimicking Metastatic Disease in a Patient with Fibrolamellar Hepatocellular Carcinoma

“…The increased calcification of the pulmonary nodules during induction chemotherapy was worrisome for the osseous differentiation of tumor cells, as can be commonly found in the mesenchymal component of hepatoblastoma after neoadjuvant chemotherapy or has been reported in other tumor types, including osteosarcoma and carcinoid tumor [ 17 ]. Osseous metaplasia with bone marrow elements has also been documented in hepatocellular adenoma with malignant transformation to hepatocellular carcinoma and in primary hepatocellular carcinoma [ 18 , 19 ]. However, osseous differentiation of FL-HCC has not been described and there are no reports of ossesous differentiation of any metastastic HCC.…”

Hepatocellular carcinoma arising from hepatic adenoma in a young woman

“…11 The histological findings are regular proliferation often in trabeculae of normal appearing hepatocytes with compressed sinusoids in between with absent bile ducts. 8,12 Although HAs are benign lesions, they do have a potential of malignant transformation. The adenoma-carcinoma sequence is defined by the presence of foci of dysplasia within adenomas, which predispose to carcinoma in situ and epithelial cancers.…”

“…10 Only a few women with no oral contraceptive medication presented malignant transformation. 10,12 Only 16% of patients among the 19 presented with multiple HAs. In most cases of HCC arising in HA, the malignant transformation was concomitant to the diagnosis of HA, as in our patient.…”

“…Multiphase CT scan is able to demonstrate characteristic findings for hepatic adenoma, but in some cases, MRI with liver‐specific contrast agent is required to lead to a final diagnosis 11 . The histological findings are regular proliferation often in trabeculae of normal appearing hepatocytes with compressed sinusoids in between with absent bile ducts 8,12 …”

“…Twelve women of the 19 reported to having malignant alteration presented with a history of contraceptive usage 10 . Only a few women with no oral contraceptive medication presented malignant transformation 10,12 . Only 16% of patients among the 19 presented with multiple HAs.…”