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SEER Inquiry System - Report
Produced: 01/29/2026 5:14 PM
Question 20000849
Inquiry Details
References:
Question:
Primary Site--Lymphoma: How should you code the primary site for a lymphoma that presents with involvement of an extranodal site and regional lymph nodes? See discussion.
Discussion:
1. Lymphoma involves the spleen and the splenic lymph nodes.
2. MALT Lymphoma involves the stomach and the gastric and iliac lymph nodes.
Answer:
1. Code the Primary Site field to C42.2 [spleen].
2. Code the Primary Site field to C16._ [stomach].
When lymphoma presents in an extranodal site and in the regional lymph nodes for that extranodal site, code the Primary Site field to the extranodal site. The typical disease process is that lymphoma can spread from an extranodal organ to its regional lymph nodes. It cannot metastasize from the regional lymph node to the extranodal organ. The exception to this would be if the lymph nodes presented as one large mass that extended into the regional organ.
Cancer Site Category:
Lymphoma
Data Item Category:
Primary site
Other Category:
N/A
Year:
2000
