An official website of the United States government
Home
SEER Inquiry System - Report
Produced: 03/07/2026 9:34 PM
Question 20210020
Inquiry Details
References:
2021 SEER Manual, 101. Behavior Code
Question:
Behavior--Breast: Should the behavior change to /3, invasive, to get a case to clear edits? The histology of this breast case is ductal carcinoma in situ (DCIS), 8500/2. Lymph nodes are positive for micro-mets (0.2 mm-2 mm). SEER Summary Stage: 3, regional lymph nodes positive. This creates an edit for SEER Summary Stage due to the behavior code of /2, in situ.
Discussion:
Answer:
Code the behavior to /3, not just to pass edits, but because this is an invasive case based on the positive lymph nodes.
For most cases, behavior is based on the primary tumor, but in situations like this where an invasive component cannot be found and there are positive lymph nodes, the /3 behavior is assigned based on the positive lymph nodes.
Cancer Site Category:
Breast
Data Item Category:
Behavior
Other Category:
N/A
Year:
2021
