An official website of the United States government
Home
SEER Inquiry System - Report
Produced: 10/17/2025 3:24 AM
Question 20190089
Inquiry Details
References:
Solid Tumor Rules, 33, 36. Lung, July 2019 Update
Question:
Solid Tumor Rules (2018)/Histology--Lung: Rule H3 of the Solid Tumor Rules was added to capture non-small cell carcinoma modified by ambiguous terminology when the physician confirms the ambiguous term as the histologic diagnosis, also included in Coding Histology instruction 3.B. If differentiation and features are not included in the histology term, does instruction 2 takes precedence? See Discussion.
Discussion:
For example, pathologic diagnosis is non-small cell carcinoma with squamous features. The medical oncologist describes this as squamous cell carcinoma and begins treatment regimen. As I interpret the rules, we would use code 8046, non-small cell carcinoma, because of instruction 2 and the fact that features is not included in the list of ambiguous terminology.
Answer:
Code 8046 using Coding Instruction 2 that says to: Code the histology described as differentiation or features/features of ONLY when there is a specific ICD-O code for the "NOS with ____ features" or "NOS with ____ differentiation."
Note: Do not code differentiation or features when there is no specific ICD-O code.
In the example, no ambiguous terminology is used. If ambiguous terminology is used indicating a more specific term, you would code to the specific histology.
