Changing the Term “Breast Tumor Resembling the Tall Cell Variant of Papillary Thyroid Carcinoma” to “Tall Cell Variant of Papillary Breast Carcinoma”

Abstract

Papillary lesions of the breast continue to be a diagnostic challenge because of the wide morphologic spectrum that may be encountered in these lesions. A rare entity termed "breast tumor resembling the tall cell variant of papillary thyroid carcinoma" is considered to be a subtype of papillary carcinoma of the breast. It is characterized by distinct morphologic features, setting it apart from typical papillary carcinoma of the breast. Its resemblance to papillary thyroid carcinoma in conjunction with the established terminology may cause confusion, resulting in unnecessary ancillary studies to exclude the association of this lesion with papillary thyroid carcinoma. As immunohistochemical and molecular studies have shown no evidence to support any association between this entity and papillary thyroid carcinoma, we propose to change the current terminology of "breast tumor resembling the tall cell variant of papillary thyroid carcinoma" to the term "tall cell variant of papillary breast carcinoma."

Breast Tumours Resembling the Tall Cell Variant of Thyroid Papillary Carcinoma: Are They Part of the Papillary Carcinoma Spectrum or a Distinct Entity?

“…A rare subtype of PC resembling the tall cell variant of thy- roid PC has been reported in the literature [12,13,[16][17][18]20] (Table 2). These tumours are characterised by the presence of tall, columnar cells arranged in nests, papillae, and follicle-like structures, and are filled with eosinophilic colloid-like material.…”

“…Other authors [18] have proposed a new terminology "tall cell variant of papillary breast carcinoma," in an attempt to avoid confusion as well as unnecessary ancillary studies aimed at excluding the association of this entity with thyroid PC.…”

“…EPC and SPC typically lack the surrounding myoepithelial cells, and they have the ability to develop LN metastasis (despite this being a rare event [2]) and are currently managed as in situ disease [7,10]. Reporting BTRTPC as IPC [15,16,18,27] without sufficient evidence of metastatic behaviour can be confusing and may result in the overtreatment of these patients in routine practice.…”

“…However, reflecting the uncertainty as to the nature and existence of this tumour as a distinct entity, several of its features are also seen in otherwise conventional PC variants [14], and variable terminology has been used to describe it [12][13][14][15][16]. Furthermore, despite being described as an oestrogen receptor (ER)-negative entity [16], a review of the literature reveals the existence of cases described as being ER-positive [13,15,17,18]. Finally, specific mutations involving the IDH2 gene have been reported in this entity [15,19], although it is not clear whether this gene mutation is a prerequisite for its diagnosis and is restricted to BTRTPC.…”

Primary breast carcinoma with features of the follicular variant of papillary thyroid carcinoma

“…[10][11][12][13][14][15][16] Histologically presenting features reminiscent thyroid follicles composed of neoplastic cells that display mostly solid to papillary architecture with areas of glandular-like formation which are filled by amorphous eosinophilic colloid-like material showing scalloped borders. Some of the tumors show abundant psammoma bodies and small aggregates of granular calcifications both within the glandular lumina and within the proliferating epithelium.…”