SEER Inquiry System - Report
Produced: 11/28/2024 11:30 AM
Question 20190102
Inquiry Details
References:
#1: ICD-O-3
#2: 2018 SEER Manual, 6-7. Reportability section
Question:
Solid Tumor Rules/Histology--Head & Neck: What is the histology code of an external ear lesion when the dermatopathology report is the only available information (follow-up with the physician or pathologist is not possible) and the final diagnosis is malignant spindle cell neoplasm, most consistent with atypical fibroxanthoma? See Discussion.
Discussion:
There are two histologies provided in the final diagnosis, malignant spindle cell neoplasm (8004/3) and atypical fibroxanthoma (8830/3). There is a definitive diagnosis of the non-specific histology, but the more specific histology is only described using ambiguous terminology.
The external ear (C442) is included in the Head and Neck schema for diagnosis year 2018 and later. The Head and Neck Histology Rules indicate ambiguous terminology cannot be used to code a more specific histology. So ignoring the atypical fibroxanthoma, because it is modified by ambiguous terminology, we are left with a non-reportable site and histology combination (C442, 8004/3).
Diagnoses of malignant atypical fibroxanthomas are regularly diagnosed using the syntax above in our area. Follow-up with the physician or pathologist is generally not possible as these cases are received from dermatopathology clinics only. The pathology report is the only information that will be received. If the reportable diagnosis of malignant atypical fibroxanthoma is ignored per the current Solid Tumor Rules, incidence cases will be lost.
Answer:
By definition, atypical fibroxanthoma (AFX) is a diagnosis of exclusion. Markers of specific differentiation must be negative. As written in your example, neither histology is reportable for skin. If possible, clarify the behavior of the AFX (8830/1) with the pathologist to determine reportability of the case.