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Produced: 10/27/2025 1:57 PM
Question 20120057
Inquiry Details
References:
#1: ICD-O-3
#2: Subject matter expert
Question:
Reportability--Appendix: Is a low grade mucinous neoplasm of uncertain malignant potential with an in situ mucinous cystadenoma component reportable? See Discussion.
Discussion:
The patient was diagnosed with pseudomyxoma peritonei and the pathology report final diagnosis stated, "Low grade mucinous neoplasm, of uncertain malignant potential, involving a dilated appendix (5cm) with the following features: In situ mucinous cystadenoma component is identified, with low-grade cytology of neoplastic epithelium." Does the presence of an in situ component make this mucinous cystadenoma of the appendix reportable based on the ICD-O-3 matrix rule?
Answer:
This diagnosis is not reportable. Cystadenoma is not reportable. The "in situ" description in this case does not make cystadenoma reportable.
According to our expert pathologist consultant, this is a "non-invasive, low grade, epithelial proliferation in an often cystic appendiceal tumor, 8480/1. If this has leaked or ruptured it can seed the peritoneal cavity causing pseudomyxoma peritonei."
Cancer Site Category:
N/A
Data Item Category:
N/A
Other Category:
Reportability
Year:
2012
