An official website of the United States government
Home
SEER Inquiry System - Report
Produced: 09/17/2025 7:09 AM
Question 20091060
Inquiry Details
References:
2007 SEER Manual. MP/H Rules
Question:
MP/H Rules/Multiple Primaries--Head and Neck: How many primaries are to be accessioned for a case in which a second tumor occurs in an area previously involved by direct extension from a prior primary located in an adjacent site? See Discussion.
Discussion:
Patient diagnosed in August 2007 with squamous cell carcinoma in the right tonsil. This tumor extended to the base of tongue. Treatment consisted of radiation and chemotherapy. In May 2008, the patient was found to have squamous cell carcinoma of the base of tongue. How many primaries are to be accessioned for this case? Rule M7 states that tumors in sites with ICD-O topography codes that are different at the second or third character are multiple primaries. The topography code for base of tongue differs from that of tonsil. Would rule M7 apply? On the other hand, the base of tongue was involved by the tonsil primary which was diagnosed less than one year before.
Answer:
For cases diagnosed 2007 or later:
The May 2008 diagnosis is not a new primary. Base of tongue involvement was originally present in August 2007. The May 2008 diagnosis does not represent new tumor. The 2007 rules apply to new tumors only; therefore, the 2007 rules do not apply to this case.
Cancer Site Category:
Head & Neck
Data Item Category:
N/A
Other Category:
Multiple primaries
Year:
2009
