ARID1A

Clear cell adenocarcinoma of the urinary tract (CCA-UT) is a rare and aggressive tumor with limited understanding of its clinicopathologic and molecular features. This multi-institutional study characterized 35 cases, showing a female predominance and advanced stage at presentation. Genomic alterations were found in 91% of cases, frequently involving chromatin modifiers such as ATRX, KMT2C, ARID1A, and ARID1B. The heterogeneous molecular profile of these tumors highlights the critical role of molecular analysis in identifying potential therapeutic targets.

This study analyzed the genomic profile of 480 patients with metastatic adenocarcinoma of unknown primary (ACUP) using the FoundationOne CDx platform. The most frequent mutations included TP53, KRAS, and CDKN2A. Results showed that GNAS and PIK3CA mutations were associated with better overall survival. Conversely, ARID1A and NOTCH1 alterations were linked to a worse prognosis. These findings highlight the significance of specific genomic alterations as prognostic markers in ACUP.