Primary small cell carcinoma of the thyroid: a case report

Abstract

The diagnosis of cervical mass is a challenge due to the wide variety of benign and malignant etiologies. Extrapulmonary small cell carcinomas (EPSCC) are rare entities, and those tumours arising as a primary cervical, especially in the thyroid gland, are exceedingly rare. As others small cell neuroendocrine carcinomas, the disease has an aggressive behavior. This case report is about a 40-years-old female patient admitted to the Hospital Felício Rocho, with airway compression caused by a cervical mass originated in the thyroid gland. The data were extracted from the medical records and information provided by the attendants. We describe here the multidisciplinary approach used to treat the patient as well as her outcome. We also review the clinical and molecular aspects of this rare entity.

Primary small cell thyroid carcinoma combined with poorly differentiated thyroid carcinoma, evidence for a common origin: A case report

“…In the 4th edition of WHO classification of thyroid tumors, high-grade neuroendocrine carcinomas are not listed as a distinctive type ( 2 ) and the fact that this tumor exhibited neuroendocrine differentiation, meant that calcitonin-negative medullary thyroid carcinoma (MTC) needed to be considered in the differential diagnosis. However, the tumor had no histological characteristics for MTC, and the morphological characteristics, such as minimal cytoplasm, nuclear molding, high mitotic figure, and immunohistochemical features such as being positive for CD56 and synaptophysin were similar to those of lung SCC ( 9 ). Sporadic MTCs are well-differentiated and locally aggressive tumors ( 12 ).…”

“…Primary SCCs have been intermittently reported previously, but most of them have presented as low-grade lymphoma or PDTC following immunohistochemical evaluation. Approximately 6–7 cases of primary small cell thyroid carcinomas (SCTCs) meeting the diagnostic criteria for small cell carcinoma have been reported in previous years ( 3 , 4 , 5 , 9 , 11 ). Eusebi et al ( 5 ) reported two cases of SCC that met the morphologic and immunohistochemical criteria for SCC.…”

“…The SCC component was positive for synaptophysin and CD56, and negative for calcitonin, chromogranin, CEA and TTF-1 ( Fig. 2E and F ) ( 9 ). Conventional nuclear features of papillary thyroid carcinoma, such as nuclear clearing, intranuclear groove and nuclear pseudo-inclusions, were not identified ( 10 ).…”