Nephrectomy for a Renal Metastasis of Undiagnosed Hepatocellular Carcinoma Arising From an Orthotopic Liver Transplant Undertaken for Cryptogenic Cirrhosis
A 70-year-old man presented with an incidental right renal mass after magnetic resonance cholangiopancreatography (MRCP) for investigation of abnormal results of liver function tests (LFTs), which suggested an obstructed biliary tree. The patient had undergone OLT in 2000 after extensive preoperative investigations for cryptogenic liver cirrhosis including serology and radiology. Post-OLT histopathology showed that the native liver had nodules of varying sizes consistent with cirrhosis with no evidence of carcinoma. The patient was started on immunosuppressive therapy with tacrolimus, which was subsequently changed to sirolimus in 2005, and he was followed up quarterly by the liver transplant service at our center.\nOn routine follow-up, the patient was found to have obstructive (cholestatic) LFT results in late 2009. An MRCP was performed and a diagnosis of choledocholithiasis was made, but incidentally a right renal mass was also found. No biliary tree obstruction or liver lesions were noted on this scan. A triple-phase computed tomographic (CT) scan of his abdomen and pelvis further confirmed the presence of a lobulated enhancing mass (55 mm×45 mm in diameter) in the right upper pole extending into the perinephric fat and abutting the right hemidiaphragm () but with a clear plane between the liver and the mass. Again, the hepatobiliary system had no lesions present. He was otherwise asymptomatic with all staging negative for metastatic disease. His case was reviewed at a multidisciplinary meeting where consensus dictated that the mass was likely to represent a primary renal tumor that should be resected. Partial nephrectomy was offered but declined by the patient.\nThe patient underwent a right open radical nephrectomy via a flank approach and resection of part of the hemidiaphragm requiring repair with a synthetic mesh (Gore-Tex patch). There were no obvious liver lesions on careful inspection and palpation. The procedure resulted in 500 mL of blood loss and no perioperative complications. Histology of the specimen revealed a tumor with hepatoid morphology () invading the upper pole of the kidney, perinephric fat, and diaphragm. Immunohistochemical staining (positive for HepPar 1 and polyclonal carcinoembryonic antigen) was also suggestive of HCC. The patient was discharged but 5 months later it was noted that his serum alpha-fetoprotein levels were significantly elevated and abnormal serum baseline liver function was declining. An ultrasound demonstrated six previously undetected focal liver lesions. A CT scan further confirmed the liver lesions, which continued to enlarge (). At restaging, new pulmonary lesions were also noted (). After a multidisciplinary meeting, the patient was commenced on the tyrosine kinase inhibitor sorafenib in a bid to control his overt metastatic disease, which at 3 months has stabilized.