Related Experiment Video
Updated: Sep 23, 2025
05:41
Author Spotlight: Integrating Ultrasound Imaging with Biochemical Markers for Thyroid Disease Diagnosis
Published on: February 9, 2024
757
Grading of Medullary Thyroid Carcinoma: an Interobserver Reproducibility Study
Jessica F Williams1,2, Melissa Zhao1,2, Fedaa Najdawi1,2
1Department of Pathology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, 02115, USA.
Endocrine Pathology
|May 13, 2022
Summary
The International Medullary Thyroid Carcinoma Grading System (IMTCGS) shows strong agreement among pathologists for assessing medullary thyroid carcinoma (MTC) grade. This grading system is both reproducible and prognostic for MTC patients.
Area of Science:
- Oncology
- Pathology
- Endocrinology
Background:
- Grading medullary thyroid carcinoma (MTC) based on proliferative activity and tumor necrosis is a recent prognostic indicator.
- Evaluating the interobserver reproducibility of MTC grading is crucial for clinical application.
Purpose of the Study:
- To assess the interobserver reproducibility of the International Medullary Thyroid Carcinoma Grading System (IMTCGS) in medullary thyroid carcinoma.
- To confirm the reliability of MTC grading by pathologists.
Main Methods:
- A cohort of 44 sporadic MTC cases was independently evaluated by three pathologist groups.
- Tumor slides were reviewed for mitotic count and necrosis; Ki-67 proliferation index was determined.
- Cases were graded using the IMTCGS, and kappa statistics were calculated for criteria and overall grade.
Main Results:
- High kappa statistics were observed for mitotic count (0.68), Ki-67 (0.86), and necrosis (0.89).
- The IMTCGS assigned grade demonstrated a strong agreement with a kappa statistic of 0.87.
- Pathologists showed a high level of agreement in assessing MTC grade.
Conclusions:
- The IMTCGS is a reproducible grading system for medullary thyroid carcinoma.
- The strong interobserver agreement supports the prognostic value and clinical utility of IMTCGS in MTC management.
