Korean J Radiol.  2015 Dec;16(6):1349-1352. 10.3348/kjr.2015.16.6.1349.

Radiologic and Pathologic Findings of a Follicular Variant of Papillary Thyroid Cancer with Extensive Stromal Fat: A Case Report

• Choi JW
• Kim TH
• Roh HG
• Moon WJ
• Lee SH
• Hwang TS
• Park KS

• KMID: 2344291
• DOI: http://doi.org/10.3348/kjr.2015.16.6.1349

Abstract

Thyroid cancer may have small adipose structures detected by microscopy. However, there are no reports of thyroid cancer with gross fat evaluated by radiological methods. We reported a case of a 58-year-old woman with a fat containing thyroid mass. The mass was hyperechoic and ovoid in shape with a smooth margin on ultrasonography. On computed tomography, the mass had markedly low attenuation suggestive of fat, and fine reticular and thick septa-like structures. The patient underwent a right lobectomy. The mass was finally diagnosed as a follicular variant of papillary thyroid cancer with massive stromal fat.

Keyword

Papillary thyroid cancer; Follicular variant; Fat; Ultrasound; Computed tomography; RAS

MeSH Terms

Carcinoma/*diagnosis/pathology/ultrasonography
Exons
Female
GTP Phosphohydrolases/genetics
Humans
Immunohistochemistry
Membrane Proteins/genetics
Middle Aged
Mutation
Thyroid Neoplasms/*diagnosis/pathology/ultrasonography
Tomography, X-Ray Computed
GTP Phosphohydrolases
Membrane Proteins

Figure

• 

  Fig. 1 58-year-old woman diagnosed with follicular variant of papillary thyroid cancer with mature fat. A. Longitudinal image of right thyroid using gray-scale ultrasonography shows hyperechoic, ovoid mass with smooth margin. Peripheral portion of mass is more echogenic than central area. Curtain-like hyperechoic shadowing was observed posterior to mass. Perithyroidal fat, muscle, and vertebral bodies were therefore not clearly visualized. B-D. Pre-contrast computed tomography (CT) shows fatty (mean CT number, -80 Hounsfield units, HU), well-defined mass in parenchyma of right mid-to-upper portion of thyroid (B). Mass has several fine reticular and thick septa-like soft tissue lesions, which show contrast enhancement. Post-contrast CT shows higher enhancement in early phase (C, at 40 seconds; mean CT number, 16 HU) of tumor than in delayed phase (D, 90 seconds; mean CT number, -13 HU). Tumor is lobular in appearance in axial plane (B-D), ovoid in longitudinal direction, and completely located in thyroid parenchyma without evidence of extrathyroidal extension. E. High-power magnification (1:400, hematoxylin and eosin staining) reveals tumor cells with enlarged nuclei, chromatin clearing, and nuclear grooves. Tumor cells are surrounded by mature adipose tissue.

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