Title : Renal autotransplantation for a hypervascular renal tumour in a solitary kidney: Ex vivo bench surgery to preserve renal function
Abstract:
Introduction: Managing complex renal tumours in a solitary functioning kidney represents a major surgical challenge, where oncological control must be balanced against avoidance of dialysis. In highly vascular or centrally located tumours, conventional nephron-sparing surgery may be unsafe due to haemorrhage risk and prolonged warm ischaemia. Ex vivo bench tumour excision with renal autotransplantation offers a nephron-preserving alternative in selected cases but is rarely performed outside specialist centres.
Case Presentation: A man in his mid-sixties with a solitary left kidney following prior donation presented with visible haematuria and urinary retention. Imaging demonstrated a hypervascular lower-pole renal mass with arteriovenous shunting and hydronephrosis. Repeated embolisation failed to fully devascularise the lesion, and biopsy was limited by bleeding risk. Multidisciplinary review concluded that in-situ partial nephrectomy carried unacceptable risk of catastrophic haemorrhage and renal failure, while radical nephrectomy would result in dialysis dependence. The patient therefore underwent laparoscopic nephrectomy, ex vivo bench tumour excision under cold ischaemia, and renal autotransplantation into the right iliac fossa.
Results: Surgery was technically demanding due to prior embolisation, dense fibrosis and distorted hilar anatomy. Warm ischaemia time was approximately five minutes and cold ischaemia just under six hours. Immediate graft reperfusion and urine production were achieved. Postoperative complications included pulmonary embolism, infected urinoma requiring drainage, and urinary tract infection, all managed successfully without graft loss. Renal function stabilised at creatinine ~150 µmol/L (eGFR 40–45 mL/min/1.73 m²), avoiding dialysis. At 20-month follow-up, imaging demonstrated no recurrence and preserved graft function.
Conclusion: Ex vivo bench surgery with renal autotransplantation can provide definitive oncological management while preserving renal function in carefully selected patients with solitary kidneys. Although associated with significant morbidity, this approach remains a valuable nephron-preserving strategy when conventional surgery is not feasible.
