A TFEB-Amplified Renal Cell Carcinoma with Long-Term, Complete Immunotherapy Response: Retrospective Support for the Value of Molecular Classification

Abstract

Recent years have seen the recognition and establishment of numerous subtypes of renal cell carcinoma (RCC), including adoption of an entire category of “molecularly defined renal carcinomas” in the fifth Edition of World Health Organization Classification. To add value, new diagnostic entities should be clinicopathologically distinct, or better, imply specific management and treatment angles, especially if adjunctive testing is needed for diagnosis. One such promising future treatment angle for a molecularly defined subtype, TFEB-amplified RCC, is immunotherapy, for which recent scholarship has demonstrated frequent expression of PD-L1. Herein, we report a case of metastatic TFEB-amplified RCC, where the patient experienced a long-term, complete response to PDL1-directed therapy, which had been serendipitously used years ago under a renal tumor subtype-agnostic indication. This promising experience suggests formal exploration of immunotherapy for these tumors.