#2: Corpus uteri
Source 1: ICD-O-3
Histology--Corpus uteri: Is 8020/3 used for a predominantly dedifferentiated carcinoma with focal well-differentiated endometrioid adenocarcinoma diagnosed in 2018? See Discussion.
After a little research, it appears as though Endometrial Dedifferentiated carcinoma is a relatively new term and is set to be included in ICD-O-3.2:
If you look at the link on that page for All Additions, Changes, and Revisions to the ICD-O-3, 1st Revision for ICDO-3.2, there is 8020/3 Dedifferentiated carcinoma. Currently, 8020/3 is Carcinoma, undifferentiated, NOS. For 2018 diagnosis, would you use 8020/3 for a predominantly dedifferentiated carcinoma with focal well-differentiated endometrioid adenocarcinoma as stated in the pathology: Uterus, bilateral ovaries and fallopian tubes; supracervical hysterectomy/BSO: Predominantly dedifferentiated carcinoma with focal well-differentiated endometrioid adenocarcinoma in the endometrium, FIGO grade 1 Portion of omentum, omental/anterior abdominal wall/ round ligament/uterine/small bowel mesenteric tumor nodules all involved by dedifferentiated carcinoma. Synoptic reads as follows: Histological Type: Endometrioid carcinoma, NOS Dedifferentiated carcinoma predominantly Histological Grade: Endometrioid carcinoma, FIGO grade 1.
Assign code 8380/3 for endometrioid carcinoma, NOS as this is listed as the histological type in the synoptic report.