Grading of medullary thyroid carcinoma on the basis of tumor necrosis and high mitotic rate is an independent predictor of poor outcome

• DOI: 10.1038/s41379-020-0532-1
• Publication Date: 2020-04-20T08:04:13Z
• Authors: Bayan Alzumaili; Bin Xu; Philip M. Spanheimer; R. Michael Tuttle; Eric Sherman; Nora Katabi; Snjezana Dogan; Ian Ganly; Brian R. Untch; Ronald A. Ghossein
• Keywords: Grading (engineering); Medullary carcinoma

Medullary thyroid carcinoma (MTC) is a rare nonfollicular cell-derived tumor. A robust grading system may help better stratify patients at risk for recurrence and death from disease. In total, 144 MTC between 1988 2018 were subjected to detailed histopathologic evaluation. Clinical pathologic data correlated with disease specific survival (DSS), local free (LRFS) distant metastasis (DMFS). Median age was 53 years (range: 3-88). tumor size 1.8 cm 0.2-11). Lymph node metastases present in 84 (58%) cases while presentation found 9 (6%) patients. Seven (5%) had ≥5 mitoses/10 HPFs. Tumor necrosis 30 (20%) lymphovascular invasion occurred 41 (28%) of tumors. Extra-thyroidal extension 44 (31%) positive margins seen 19 (14%). There strong correlation increasing (p < 0.001). follow up 39 months. univariate analysis, male gender, higher American Joint Committee on Cancer (AJCC) stage group, larger size, necrosis, high mitotic index (≥5/10 HPF), nodal status, largest metastasis, elevated postoperative serum calcitonin predicted worse DSS, LRFS, DMFS 0.05). DSS imparted multivariate activity (5 mitosis/10 HPFs as the cutoff) only independent predictors = 0.008 0.026, respectively). sole prognostic factor LRFS 0.001 0.003, The presence rate are powerful factors outperform stage. We propose based counseling, post-resection surveillance, therapy.