Histopathology report: multiple, partly hyalinised connective tissue septae with round cell infiltration and pigmented foam cell aggregates. Predominantly one-layered, eosinophilic epithelial cystic wall. Intracystic eosinophilic secretion. Solitary cholesterol granulomas and focal calcifications. No signs of malignancy.

Cystic nephroma with focal regressive changes.