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Produced: 10/29/2025 10:43 AM
Question 20200067
Inquiry Details
References:
2018 Summary Stage. Colon and Rectum
Question:
Summary Stage 2018/Extension--Colon: What is the Summary Stage for adenocarcinoma of cecum where the tumor extends into the proximal portion of attached vermiform appendix? See Discussion.
Discussion:
2020 Diagnosis: Patient had a right hemicolectomy showing adenocarcinoma of cecum, tumor extends into proximal portion of attached vermiform appendix. Tumor invades through muscularis propria into pericolorectal tissues (NOS). Regional lymph nodes: 06/39. Primary Tumor EOD: Where does the appendix involvement come into coding or will this be based on the pericolorectal tissue (NOS) invasion? What is my Summary Stage? I know it is at least 3 due to regional ln involvement, but the appendix involvement is making me question 3 vs 4.
Answer:
Assign code 4, Regional by BOTH direct extension AND regional lymph node(s) involved. In this case, the Regional component for Summary Stage 2018 is based on Note 6, under Colon and Rectum where Regional is defined as:
-Mesentery
-Peritonealized pericolic/perirectal tissues invaded [Ascending Colon/Descending Colon/Hepatic Flexure/Splenic Flexure/Upper third of rectum: anterior and lateral surfaces; Cecum; Sigmoid Colon; Transverse Colon; Rectosigmoid; Rectum: middle third anterior surface]
-Pericolic/Perirectal fat
