Report of case series: Correlation between pathological and radiological evaluation and clinical course of three cases of metastatic renal cell carcinoma with cytoreductive nephrectomy after combined immuno-oncology therapy.

Introduction: The pathologic evaluation and clinical course of cytoreductive nephrectomy after combined immuno-oncology therapy were reviewed to understand the benefits of cytoreductive nephrectomy. Case presentation: Three patients with clear cell carcinoma underwent tumor biopsy before combined immuno-oncology therapy. Case 1 was found to have a sarcomatoid component upon nephrectomy and continued with combined immuno-oncology therapy. Case 2 discontinued combined immuno-oncology therapy due to adverse events but maintained tumor shrinkage. The patient was found to have viable cells in most nephrectomy specimens but has had no recurrence after combined immuno-oncology therapy was discontinued. In case 3, the residual tumor was deemed resectable with combined immuno-oncology therapy, and nephrectomy and metastasectomy were performed. No viable cells were observed in either specimen, and the patient has had no recurrence. Conclusion: Cytoreductive nephrectomy after combined immuno-oncology therapy may be useful to allow pathologic evaluation of treatment and provide an indicator for subsequent treatment.