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SEER Inquiry System - Report
Produced: 10/14/2025 9:50 AM
Question 20051145
Inquiry Details
References:
#1: TNM Supplement, 9. 3rd Edition, 2003
#2: 2004 SEER Manual, 130, C-222
Question:
CS Extension/CS Mets at Dx--Colon: How is a small focus of metastatic disease in the submucosa coded for a sigmoid primary? See Discussion.
Discussion:
Path final diagnosis states: "No lymph node metastases identified. One submucosal met in a block taken from a surgical margin section." Path micro states: "Microscopic involvement of the border between the serosa and muscularis propria. Sections of proximal & distal surgical margins reveal no tumor in one, and a small focus of metastatic disease in the submucosa of the other. This focus of tumor exists in a small vascular channel and is complete in and of itself; ie, it has not been cut thru by excision of the specimen from the patient."
Answer:
This answer was provided in the context of CSv1 coding guidelines. The response may not be used after your registry database has been converted to CSv2.
This submucosal metastasis does not affect CS extension. It is not part of CS or TNM staging.
According to the TNM supplement, "Multiple tumour foci in the mucosa or submucosa ("skip metastasis") are not part of the TNM classification and should not be classified as distant metastasis.
