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SEER Inquiry System - Report
Produced: 04/04/2026 7:03 AM
Question 20100063
Inquiry Details
References:
2010 SEER Manual
Question:
Primary Site-Lung: Can you use a lung subsite code for a histologically confirmed lung primary when a CT scan indicates a sized mass located in one lobe of the lung as well as "too numerous to count nodules" through one or both lungs? See Discussion.
Discussion:
For example, chest CT shows "1.6 cm RUL suspicious mass and too numerous to count nodules throughout both lungs." Core biopsy of mass in the RUL compatible with adenocarcinoma.
Answer:
For lung primaries with one large mass and numerous nodules, code the primary site to the subsite where the large mass is located. For your example, code the primary site to C341 [upper lobe of lung]. Note: This answer does NOT mean that the other nodules are primary or metastatic cancer.
Cancer Site Category:
Lung
Data Item Category:
Primary site
Other Category:
N/A
Year:
2010
