Bosniak renal cyst classification

Bosniak Cyst Type 2

Minimally complex, single thin (< 1mm) septations, thin Ca++; non-enhancing high-attenuation (due to to proteinaceous or hemorrhagic fluid) renal lesions of less than 3 cm are also included in this category; these lesions are generally well marginated.

Work up : nil% 

Malignant : ~ 0 

Beautiful diagrams of cyst types -  http://radiopaedia.org/cases/diagram-bosniak-classification-of-renal-cysts