SEER Inquiry System - Report
Produced: 12/11/2023 3:41 AM
#1: WHO Class Endocrine Tumors, online. 5th edition
Reportability/Histology--Thyroid: Is a diagnosis of papillary carcinoma, follicular variant, encapsulated/well demarcated, non-invasive reportable? See Discussion.
The final diagnosis for a left thyroid lobectomy was Papillary thyroid microcarcinoma, further stated to be Histologic Type: Papillary carcinoma, follicular variant, encapsulated/well demarcated, non-invasive. The diagnosis comment states there is a small follicular pattern papillary microcarcinoma.
Is the designation of “non-invasive” for this papillary follicular tumor equivalent to a non-reportable diagnosis of Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), 8349/1? Or should this be accessioned as either a reportable in situ (non-invasive) papillary follicular thyroid carcinoma or a papillary microcarcinoma per the diagnosis comment?
Your case is equivalent to encapsulated follicular variant of papillary thyroid carcinoma, non-invasive (non-invasive EFVPTC) and is not reportable for cases diagnosed in 2021 or later even though it says "carcinoma." That is because the WHO assigned a behavior code of /1 to this entity (8349/1). NIFTP is assigned to the same histology and behavior code.