Calcifying Nested Stromal-Epithelial Tumor (CNSET) of the Liver: A Case Report With Its Molecular Profile.

Calcifying Nested Stromal-Epithelial Tumor (CNSET) of the liver is a hepatic neoplasm of uncertain lineage, primarily affecting young individuals. This case report aims to elucidate the clinical, histopathological, and molecular characteristics of CNSET, contributing to the sparse knowledge regarding this unusual entity. We present here a 17-year-old female patient diagnosed with CNSET, highlighting the tumor's radiologic appearance, surgical management, and postoperative findings, alongside a comprehensive review of existing literature on the subject.The patient was evaluated for obesity and discovered to have a liver mass through imaging studies. The tumor demonstrated distinctive MRI features and was surgically resected, with histopathology confirming the diagnosis of CNSET. Molecular analysis revealed CTNNB1 and TERT promoter mutations.This case report underscores the importance of considering CNSET in differential diagnoses of liver tumors in young patients and adds valuable insights into its molecular underpinnings, emphasizing the need for further research to understand its pathogenesis and optimize management strategies.