An official website of the United States government
Home
SEER Inquiry System - Report
Produced: 09/16/2026 2:03 PM
Question 20100061
Inquiry Details
References:
2010 SEER Manual, 7
Question:
MP/H Rules/Histology: The 2010 SEER Manual has omitted some useful information in the Histologic Type ICD-O-3 section, specifically the statement of "Do not revise or update the histology code based on subsequent recurrence(s)". Will this statement be added to the revisions of the MPH rules? See Discussion.
Discussion:
Example: A 2005 diagnosis of left breast lobular carcinoma [8520/3], followed by a 2009 diagnosis of left breast ductal carcinoma [8500/3]. Rule M10 states this is a single primary, but there is no information in the Histology rules (Multiple Tumors Abstracted as a Single Primary) that the original histology should be retained, thus a person could potentially use these rules to change the original histology to 8522/3 [duct and lobular carcinoma] per rule H28.
Answer:
We will reinstate the instruction not to change the histology code based on recurrence in future versions of the histology coding instructions. However, this instruction may not be applicable to all anatomic sites. It will be reinstated on a site-by-site basis. You may also refer to the instructions on Page 7 of the 2010 SEER Manual under the heading "Changing Information on the Abstract."
Cancer Site Category:
N/A
Data Item Category:
Histology
Other Category:
N/A
Year:
2010
