ABSTRACT
After radical nephrectomy, clear cell renal cell carcinoma (ccRCC) recurs locally in <3% of patients. Recurrences typically occur 1-2 years postoperatively and grow at 5-20 mm per year. In contrast, this patient's recurrence was unexpectedly large and swift. A 71-year-old woman was initially found on workup for recurrent urinary tract infections to have a 12 cm left renal tumour. After negative staging scans, she progressed to left open radical nephrectomy. Histology revealed a stage T2b 12 cm ccRCCwith sarcomatoid differentiation, International Society of Urological Pathology (ISUP) grade 4, with clear margins. Only 3 months later, the patient developed left-sided abdominal pain, and CT scans revealed a 15 cm left retroperitoneal local recurrence, as well as widespread peritoneal tumours. In discussion with her treating team, the patient and her family elected not to undergo biopsy or systemic therapy. The patient was palliated and passed away 8 days after re-presentation.