Gleason scoring is used for-

Gleason's microscopic grading system which is based on two features:i) Degree of glandular differentiation.ii) Growth pattern of the tumor in relation to the stroma.These features are assessed by low-power examinationof the prostatic tissue. For clinical staging of prostate cancer,TNM system is considered an international standard. HARSH MOHAN Textbook of pathology 6th edition pg no 720