Eosinophilic vacuolated tumor of the kidney can have distant metastasis: a histo-molecular case study.

Eosinophilic vacuolated tumor (EVT) is an emerging renal entity and further studies are required to characterize this neoplasm. EVT is considered generally indolent because metastasis or death from the disease has never been reported. Herein, we report the first case of EVT with mediastinal lymph node metastasis to validate its at least borderline behavior. Based on the morphological features, we additionally used a large panel of immunohistochemical antibodies and next-generation sequencing (NGS) to confirm the diagnosis of EVT and exclude other renal entities. This case report highlights the notion that EVT can exhibit mediastinal lymph node metastasis and patients with EVT need to be closely followed.