Intravenous bevacizumab therapy post-nephroureterectomy resulted in no recurrence or metastasis at 28 months follow-up in a patient with primary renal pelvic undifferentiated pleomorphic sarcoma.
Case Report (n=1)
No
This case provides the first evidence that primary undifferentiated pleomorphic sarcoma of the renal pelvis can yield a false-positive urine FISH and exhibit high PD-L1 expression, suggesting a potential role for targeted therapy.
Primary undifferentiated pleomorphic sarcoma (UPS) of the renal pelvis is an extremely rare and aggressive mesenchymal malignancy. The diagnosis remains challenged, and its clinical characteristics and treatment strategies remain unclear. Urine fluorescence in situ hybridization (FISH) is a highly sensitive tool for detecting urothelial carcinoma (UC), but ‘false’-positive results can be observed in non-UC malignancies. We present a challenging case of primary UPS of renal pelvis with positive urine FISH and high programmed death receptor ligand 1 (PD-L1) expression, which complicates the initial diagnosis and opens avenues for potential immunotherapy.
Li et al. (2026) conducted a case report in A 75-year-old female patient with primary undifferentiated pleomorphic sarcoma of the renal pelvis presenting with gross hematuria and a renal pelvic mass (n=1). Intravenous bevacizumab therapy was evaluated on Recurrence or metastasis rate after nephroureterectomy and bevacizumab therapy. Intravenous bevacizumab therapy post-nephroureterectomy resulted in no recurrence or metastasis at 28 months follow-up in a patient with primary renal pelvic undifferentiated pleomorphic sarcoma.