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SEER Inquiry System - Report
Produced: 10/30/2025 1:29 AM
Question 20031140
Inquiry Details
References:
ICD-O-3, 32. Rule H
Question:
Primary site--Unknown & ill-defined site/Kidney: How should this field be coded when humeral metastases are compatible with renal cell carcinoma pathologically, no kidney lesion is found clinically and the physician's signout diagnosis is "no primary found, as of now unknown"? See Description.
Discussion:
Path states "biopsy of humerus, mets sarcomatoid carcinoma consistent with renal cell carcinoma." Material was sent to Mayo Clinic for consult & they state "with focus of clear cells, agree that a likely primary is renal cell carcinoma." Abdominal CT showed no abnormality in kidneys. When the registrar abstracted the case she spoke to the managing physician who told her that "no specific site was found and it was, as of now, unknown." This was stated about three months after dx. Can we code as a renal primary based on pathologic information or should we code unknown based on CT and physician's statement?
Answer:
Code this case to C64.9 [Kidney, NOS].
ICD-O-3 rule H states that the topography code attached to a morphology term may be used when the topographic site is not given in the diagnosis. Topography code C64.9 is attached to morphology code 8312/3 [Renal cell carcinoma] in ICD-O-3.
Cancer Site Category:
Unknown & ill-defined sit, Kidney, renal pelvis
Data Item Category:
Primary site
Other Category:
N/A
Year:
2003
