A 62-year-old man referred to our facility for the management of abnormal computed tomography of the chest identified during investigation for atypical chest pain. His past medical history was significant for chronic hepatitis C complicated by liver cirrhosis and hepatocellular carcinoma (HCC). He underwent chemoembolization and radiofrequency ablation of the liver as bridging therapies prior to uneventful orthotopic liver transplantation (OLT), a curative treatment for HCC. The explanted liver was cirrhotic and contained two 4.5 cm extensively necrotic lesions consistent with poorly differentiated HCC on pathological examination. There was an extensive intravascular invasion, and tumor was presented within an intracaval thrombus, which was removed during surgery. After the OLT, he was maintained on immunosuppressive therapy with tacrolimus and prednisone. Unfortunately, he was diagnosed with prostate cancer a few months later and underwent prostatectomy as curative treatment. At this time, his immunosuppressant was changed from tacrolimus to sirolimus, which had shown to delay HCC recurrence when compared to regimens that use tacrolimus in retrospective study.
Physical examination of his chest revealed normal breath sounds. Cardiovascular examination was unremarkable for abnormal heart sounds or murmurs. The rest of his physical examination was normal. Cardiac workup was negative for myocardial injury. Computed tomography of his chest images is shown in Figure 1. The patient subsequently underwent endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) of right paratracheal lymph node station 4R (Figure 2).
Pathological examination revealed highly cellular and clusters of large, loosely cohesive sheets of tumor with thin-walled traversing blood vessels. The tumor cells had a moderate amount of granular cytoplasm containing occasional hyaline globules. Nuclei were round to oval in shape and moderately pleomorphic, with prominent nucleoli and scattered intranuclear pseudoinclusions. Bile pigment was not identified. Numerous nuclei stripped of cytoplasm were present in the background of the smears (Figure 3). The specimen did not contain appreciable lymphoid tissue, but small aggregates of macrophages with anthracotic pigment were present; these macrophages indicate that the tumor was located within a mediastinal lymph node (Figure 4). Immunohistochemical stains were positive for hepatocyte paraffin 1 (HepPar1) (Figure 5) and alpha-fetoprotein (AFP), and stains for cytokeratin (CK)-7, CK-20, thyroid transcription factor-1 (TTF-1), and monoclonal carcinoembryonic antigen (CEA) were all negative.
Recurrent metastatic HCC in mediastinum.