Abstract
BACKGROUND: Sarcomatoid transformation in renal cell carcinoma, termed sarcomatoid renal cell carcinoma (SRCC), is associated with aggressive behavior and an unfavorable prognosis. The presence of sarcomatoid differentiation poses a therapeutic challenge due to limited response to existing systemic therapies; however, advances in drugs with immune checkpoint inhibitor (ICI) have improved response rates. CASE DESCRIPTION: We report the case of a middle-aged woman diagnosed with multiple metastatic SRCC, treated with a combination of pembrolizumab plus axitinib as first-line therapy, transarterial chemoembolization, and nephrectomy. The patient ultimately achieved complete remission but presented with severe colitis symptoms. Following the cessation of pembrolizumab and axitinib therapy for 1 year, her colitis symptoms gradually resolved, with no evidence of recurrence or metastasis observed during that time. Her survival period has now extended beyond 2.5 years. CONCLUSION: Metastatic sarcomatoid renal cell carcinoma is associated with very poor prognosis, with a survival period of <1 year despite systemic therapy. In this present case, the patient achieved long-term survival following multidisciplinary treatment-a rare occurrence worthy of report.