Columnar cell carcinoma of the thyroid, which was first described by Evans1 in 1986, is an aggressive variant of PTC. In Evan's initial description of 2 cases, he noted that the columnar cell variant was characterized by thin fibrovascular cores lined by elongated columnar cells with marked nuclear stratification. Although the papillary architecture was well developed and psammoma bodies were sometimes seen, these tumors lacked the ground glass nuclear appearance that hallmarks conventional PTC. Indeed, columnar cell carcinoma more closely resembles carcinomas from other sites than conventional PTC. For example, an immunohistochemical stain for thyroglobulin (Figure 3) may be necessary to rule out a metastatic carcinoma from the endometrium or colorectum. Since Evans' initial report, other investigators have described primary thyroid carcinomas with similar morphological findings.2- 4 Many believe that the distinct morphological features and clinical behavior of columnar cell carcinoma clearly set it apart from other primary carcinomas of the thyroid gland. Nonetheless, according to the World Health Organization classification scheme, columnar cell carcinoma is considered a variant of PTC.
Pathologic Quiz Case 1. Arch Otolaryngol Head Neck Surg. 1998;124(10):1172. doi:10-1001/pubs.Arch Otolaryngol. Head Neck Surg.-ISSN-0886-4470-124-10-orp8196