Primary high-grade calcitonin-negative neuroendocrine carcinoma of the thyroid: a very rare cancer. (17th April 2018)

• Record Type: Journal Article
• Authors: Chorny, Joseph A; Orrego, John J; Cameselle-Teijeiro, José Manuel
• Is Part Of: Endocrinology, diabetes & metabolism case reports. (2018)
• Publication Date: 2018-04-17
• Subjects: Adult -- Female -- White -- United States; Thyroid -- Endocrine-related cancer -- Thyroid carcinoma -- Neuroendocrine tumour -- Medullary thyroid cancer -- Hypothyroidism; Neck mass -- Core needle biopsy -- CD-56 -- Synaptophysin -- Thyroid transcription factor-1 -- PET scan -- Ultrasound scan -- Immunostaining -- Haematoxylin and eosin staining -- Radiotherapy -- Chemotherapy -- Cisplatin -- Etoposide; Oncology; New disease or syndrome: presentations/diagnosis/management -- April -- 2018; Endocrinology -- Periodicals; Diabetes -- Periodicals; Diabetes Mellitus; Endocrinology; Diabetes; Endocrinology; Case Reports; Periodicals; Periodicals; 616.4
• DOI: 10.1530/EDM-18-0036
• Languages: English
• ISSNs: 2052-0573

Abstract

Summary: Most medullary thyroid carcinomas (MTCs) are low grade and produce calcitonin. There are some calcitonin-negative MTCs that produce only calcitonin gene-related peptide (CGRP). Rarely, MTCs are negative for calcitonin and CGRP peptides, but contain their corresponding mRNAs. Primary thyroid neuroendocrine neoplasms other than MTCs are extremely rare. We describe a primary high-grade neuroendocrine carcinoma that was negative for CGRP and calcitonin at both the protein and mRNA levels. A 42-year-old woman presented with a rapidly enlarging thyroid mass replacing most of the left lobe and isthmus. A computed tomography-guided core-needle biopsy was performed. The tumor was composed of sheets of small-to-medium sized epithelial cells. The cells were immunoreactive for pancytokeratin, synaptophysin, CD56 and thyroid transcription factor-1, but negative for CK7, CK20, CD45, CD99, ERG, chromogranin A, thyroglobulin, calcitonin, CGRP and carcinoembryonic antigen. The Ki-67 proliferation index was ~90%. In situ hybridization was negative for calcitonin mRNA. The patient was initially diagnosed as having a small cell carcinoma. She was treated with cisplatin and etoposide (VP16), followed by radiation therapy. Given the excellent clinical course, the tumor was reviewed and reclassified as a high-grade neuroendocrine carcinoma (non-small-cell type). Heretofore, only a few other similar high-grade neuroendocrine tumors with negative markers of C-cell derivation have been reported. In our case, the patient is cancer free five years after diagnosis, but in the other cases, the outcome was poor. Learning points: There are neuroendocrine carcinomas of the thyroid that do not produce calcitonin or calcitonin gene-related peptide. This category of calcitonin-negative neuroendocrine carcinomas is heterogeneous, consisting of low- and high-grade tumors. The high-grade neuroendocrine carcinomas of the thyroid are rare and generally have a poor prognosis. They are divided into small cell and non-small cell or large cell types.