Abstract 3525: Epidemiology and clinicopathology prognostic factors of TFEB translocation renal cell carcinoma (TBRCC): Analysis of updated pooled database

Abstract

Renal cell carcinomas harboring the t(6;11) (p21;q12) translocation with a specific Alpha(MALAT1)-TFEB gene fusion is a recognized rare subtype of the Microphthalmia Transcription factor (MiT) family of translocation RCC. TBRCC is an indolent disease that occurs at a younger age. Though it may take on a wide spectrum of morphology, TBRCC has been classically characterized by distinctive biphasic morphology with larger epithelioid cells and smaller cells clustered around eosinophilic spheres formed by basement membrane material. This analysis was conducted to update and expand our existing knowledge of this rare disease. In order to study the demographic characteristics, cytogenetic and molecular signatures, survival, and prognostic factors, we compiled a pooled database of 140 cases. Kaplan-Meier survival curves were constructed. Cox proportional-hazards model and Log-rank tests were used to assess the influence of demographic and clinicopathologic factors on survival. The median age was 32 (3-78) years with a peak incidence between ages 17 and 30 years. Males and females were afflicted equally. The median overall survival (OS) of the whole group was not reached with more than 78% alive at 10 years. The group's median disease-free survival (DFS) was 96 months. Six percent of this cohort recurred. Among patients who recurred, the median time to recurrence was 24(6-75) months. Sex did not impact OS or DFS. Similarly, the molecular partner of the TFEB gene fusion, Alpha (MALAT1) versus others, did not seem to impact OS or DFS. The presence of necrosis seemed to adversely impact OS (HR:14.3, p<0.0001) and DFS (HR:14.4, p<0.0001). Nuclear grade negatively impacted DFS, the higher the grade the worse the DFS. The presence of eosinophilia, psammoma bodies, and pigmentation did not affect OS or DFS. Similarly, the histologic morphology, biphasic vs others, did not affect OS or DFS. Multivariate analysis revealed older age (HR:1.08, p=0.01) and larger tumor size (HR:10.12, p=0.002) adversely impacted OS. This study presents an updated epidemiologic and clinicopathologic data from a pooled cohort of patients with TBRCC. Age, size, and necrosis were found to adversely impact the OS. However, higher nuclear grade only adversely impacted the cohort's DFS. Citation Format: Philip A. Haddad, Dalia Hammoud, Kevin Gallagher. Epidemiology and clinicopathology prognostic factors of TFEB translocation renal cell carcinoma (TBRCC): Analysis of updated pooled database [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3525.