Morphology & Grade
ICD-O-3 Morphology Codes
- Adenocarcinoma (81403; 95% of all prostate cancers)
- Rare histologies
- Transitional cell carcinoma (81303)
- Small cell carcinoma (804_3)
- Squamous cell carcinoma (807_3)
- Grade 1 (G1) Well-differentiated, slight anaplasia
- Grade 2 (G2) Moderately differentiated, moderate anaplasia
- Grade 3-4 (G3-4) Poorly differentiated or undifferentiated, anaplastic, marked anaplasia.
Gleason's system assigns histologic grade to predominant (primary) and lesser (secondary) pattern of tumor. The grade numbers of the two patterns are added to obtain the Gleason score, which may range from 2 to 10.
|Gleason's Pattern||Gleason's Score||Histologic Grade||Differentiation
|1, 2||2, 3, 4||I. Well-differentiated||1|
|3||5, 6||II. Moderately differentiated||2|
|4, 5||7, 8,9,10||III. Poorly Differentiated||3|
* Also FORDS scores a 7 as Poorly Differentiated 3