TSC1

This retrospective study investigated eight cases of multifocal micronodular pneumocyte hyperplasia (MMPH) associated with tuberous sclerosis complex (TSC), a rare benign pulmonary lesion. Patients typically presented with multiple ground-glass nodules in the lungs on CT scans and various clinical manifestations of TSC. A significant diagnostic challenge was highlighted, as intraoperative frozen sections were often misdiagnosed as early-stage lung adenocarcinoma. Next-generation sequencing revealed TSC1 or TSC2 gene mutations in most patients, confirming the association with TSC. All followed-up patients showed a favorable overall survival.

This retrospective study investigated the frequency and molecular profiles of PAX8-positive conventional urothelial carcinomas (UCs) of the urinary bladder. Out of 101 cases, 10% were found to be PAX8-positive by immunohistochemistry. Next-generation sequencing (NGS) was performed on 20 cases, including all PAX8-positive UCs. The findings revealed that PAX8-positive UCs frequently harbored TERT promoter mutations, TSC1 alterations, NOTCH1 loss, and WT1 loss, while notably lacking RB1 loss, distinguishing them from PAX8-negative UCs. These results indicate a distinct molecular signature for PAX8-positive UCs, emphasizing the need for careful diagnostic interpretation of PAX8.