Renal squamous cell carcinoma postoperative recurrence treated with sunitinib combined with radiotherapy: a case report.

Background: Primary renal squamous cell carcinoma (SCC) is an extremely rare and aggressive malignancy, accounting for less than 1% of all renal tumors. Due to its rarity, there is no standardized treatment guideline, and the prognosis is generally poor. Case Description: This report presents a case of locally advanced renal SCC that developed local recurrence after nephrectomy and was successfully treated with sunitinib combined with radiotherapy (RT). A 56-year-old male presented with right flank pain and was diagnosed with right renal SCC (keratinizing type). The patient underwent radical nephrectomy with resection of the involved psoas muscle. Pathological examination revealed pT4N0Mx tumor with lymphovascular invasion. One month postoperatively, tumor recurrence was detected, and the patient subsequently received treatment with sunitinib [a tyrosine kinase inhibitor (TKI)] combined with TomoTherapy to the recurrent lesion. Following treatment, the patient achieved a partial response, with significant improvement in performance status (Karnofsky Performance Status score increased from 60 to 90), weight gain of 8 kg, and resolution of anemia. No distant metastasis was observed during follow-up. Conclusions: This case suggests that the combination of sunitinib and RT may represent a potentially effective treatment strategy for postoperative recurrence of locally advanced renal SCC, though further studies are warranted to validate this approach.