Hepatic Metastases With No Primary Source

Abstract

Introduction: In the absence of biliary obstruction, cirrhosis, and focal primary liver tumors, metastases to the liver originate most commonly from colorectal and, less commonly, renal cell malignancies. Renal cell carcinoma (RCC) rarely metastasizes to the liver, about less than 4%. Case Report: A 66-year-old woman with a of history of end-stage renal disease on hemodialysis and autosomal dominant polycystic kidney disease (ADPKD) since 2005 status post bilateral nephrectomy greater than 10 years ago was admitted for periumbilical pain with nausea and 8 episodes of non-bloody, non-bilious vomiting within a period of 2 weeks. The patient did not have fevers, diarrhea, weight loss, or weight gain. The patient had an endoscopy and a colonoscopy about 2 weeks prior to this admission. At that time, endoscopy showed gastritis and duodenitis, and colonoscopy confirmed diverticulosis. Examination revealed normal vital signs, moderate tenderness in the periumbilical area. The SMA showed BUN 26 and creatinine 4.5. The patient had a normal white cell count, hemoglobin, hematocrit, platelets, and INR of 1.09. The patient also had normal liver function enzymes, bilirubin, and lipase. Alphafetoprotein 6.0 and CEA 1 were both within normal limits. Vomitting resolved, but nausea persisted. Abdominal CT with oral and intravenous contrast: multiple diffuse hepatic masses with questionable capsular invasion were also noted on prior CT and MRI scan in 2012. The liver was also noted to be heterogeneous with multiple smaller masses and multiple diffuse small hepatic cysts. Other findings in the study include an Inferior vena cava filter, diverticulosis at the left lower quadrant abdominal area, and pleural thickening at the lung bases. Due to concern for increased size in hepatic masses, CT-guided biopsy was taken, showing metastatic RCC as the most likely type of the tissue. Other possibilities of clear cell carcinoma include melanoma, rarely pecoma, alveolar sarcoma, and adrenal cortical carcinoma. Based on the patient’s immunoprofile of PAX 8+,CAM 5.2+, CK7-, CK20- tissue markers, the most likely identifiable tissue is renal cell carcinoma or derivable tumors from mesonephric tumors. The patient had a history of documented hepatic cysts likely secondary to polycystic kidney disease; however, the growing heterogeneous hepatic masses were less likely explainable by polycystic kidney disease alone. RCC metastases to the liver are uncommon; however, a patient with a bilateral nephrectomy >10 years ago secondary with liver metastases of RCC has never been documented. The patient wished for no further investigation or intervention at this point, and her abdominal pain was symptomatically managed.