Hepatoid adenocarcinoma of the renal pelvis in a 59-year-old male with nephrolithiasis: Case report and review of the literature.

BACKGROUND: Hepatoid adenocarcinoma arising from urological system is extremely rare, and the pathogenesis and therapeutic regimen have been poorly understood.

CASE REPORT: we report a unique case of ɑ-fetaprotein (AFP)-producing neoplasm of renal pelvis associated with nephrolithiasis. A 59-year-old male patient was diagnosed with right renal tumor and nephrolithiasis with no evidence of lesions in his digestive or reproductive system. He was successfully treated with right laparoscopic radical nephroureterectomy and lymph node dissection. Pathology analysis showed moderately or poorly hepatocellular differentiation and adenocarcinoma differentiation with lymph node reactive hyperplasia. Immunohistochemical analysis demonstrated that the cancer cells were positive for AFP, HepPar-1, GPC3, CK7, and PLAP. The patient's recovery was on schedule and no sign of recurrence was observed for 3 months. We recently reviewed AFP-producing nongerm cell tumors in upper urinary tract and discussed the clinical aspect, morphology features, pathogenesis, and therapeutic regimen for a better understanding of this rare entity.

CONCLUSION: The present case is the first documented of hepatoid adenocarcinoma of renal pelvis complicated with nephrolithiasis, which was treated with laparoscopic approach. The prognosis of the hepatoid adenocarcinomas arising from renal pelvis and ureter seems good.