Evaluation of Gastroenteropancreatic Neuroendocrine Tumors

The incidence of Gastroenteropancreatic Neuroendocrine Tumor (GEP-NET) was shown to be steadily increasing (~4-5% per year), especially in the older population, by a recent publication by Lee et al.¹ As the patients’ survival is directly related to their management, the treating oncologist is heavily dependent on the correct grading/staging by the pathologist. Currently there is a lack of clarity with the scoring of Ki67 staining and the best specimens to test.

Scope

The primary goal of this guideline is to provide evidence-based recommendations on the evaluation of GEP-NETs. The guideline scope begins with specimens submitted to the laboratory with confirmed diagnosis of GEP-NET. Specimens under review will include fine needle aspirations, biopsies, surgical resections of both primary tumors, and metastases.

Key Questions

The draft overarching questions include:

• What is the best Ki67 scoring method of assigning grades in GEP-NETs?
• What are the best specimens to grade in GEP-NETs?

Key questions would be developed around the pre-analytic factors of specimen adequacy and the analytic factors of testing, counting, and interpretation.

Guideline Information

Guideline Status: Determine Scope and Form Panel

Review more upcoming CAP evidence-based guidelines by the Center.

1. Lee MR, Harris C, Baeg KJ, et al. Incidence trends of gastroenteropancreatic neuroendocrine tumors in the United States [published online December 20, 2018]. Clin Gastroenterol Hepatol. 2018. doi: 10.1016/j.cgh.2018.12.017