Question: 20210006

Status


Final

Category


#1:   Behavior
#2:   Summary Stage 2018
#3:   Colon


References


Source 1:   Summary Stage 2018 Coding Manual v2.0
pgs:   147
Notes:   September 2020
Source 2:   AJCC Cancer Staging Manual
pgs:  
Notes:   8th edition


Question


Behavior/Summary Stage 2018--Colon:  What is the correct behavior and Summary Stage for a case of intramucosal adenocarcinoma arising in tubular adenoma? AJCC states this is Tis, though SEER Summary Stagie states this is Localized (code 1).  The histology is 8140/2 (adenocarcinoma in situ), but the SEER Summary Stage is Locallized.



Discussion




Answer


Intramucosal carcinoma of the colon is assigned behavior code of /3. Intramucosal is not the same as in situ in terms of behavior. Behavior and staging are separate concepts, although there is some overlap. Use the instructions for coding behavior to code this field. Do not use stage to determine behavior in this case.

For purposes of Summary Stage, intramucosal carcinoma is a localized lesion; however, for purposes of AJCC staging, assign Tis for the stage.



History




Last Updated


01/15/2021

Date Finalized


04/02/2021