PAPILLON COURSE on THYROID ULTRASOUND

Section 2 The nodular goiter

Part 7 Extrathyroidal spread
Lectures

 

Table 4. The issue of identical echogenicity

We meet this pattern in cases in which the echogenicity of the nodule is identical to the neighboring extrathyroidal parenchyma. In most cases, this occurs in the event of deeply hypoechoic nodules which are in at the ventral surface of the lobe.

Papillary carcinoma (histology) - case conp026
Transverse scan
Longitudinal scan

The more hypoechogenic thyroid infiltrates the less hypoechogenic strap muscle. The borders between the former (yellow) and the latter (red) are pointed with arrows.

Papillary carcinoma (histology) - case conp062
Transverse scan
Longitudinal scan
This is a highly suspicious exapmle of extrathyroidal spread. The degree of bulging is high compared to the mass of the lesion. We cannot differentiate the tumor from the strap muscle.

Papillary carcinoma (histology) - case conp008
Transverse scan
Longitudinal scan

The border between the ventral part of the hypoechogenic nodule and the dorsal part of the strap muscle cannot be determined (yellow arrows). Moreover, the echogenic line, the connective tissue running in the ventral surface of the thyroid (red arrows) has been broken (red arrowheads) which increases the likelihood of extrathyroidal spread.
Papillary carcinoma (histology) - case conp003
Transverse scan
Longitudinal scan

The tumor has partly blurred (red arrows) and partly spiculated (yellow arrows) margins. The extent of blurred part of the border exceeds 50%. Green arrows point to that part of the nodule which echogenicity is identical to the extrathyroidal strap muscle. In such cases we can neither prove nor exclude the possibility of extrathyroidal spread.

Papillary carcinoma (histology) - case conp014
Transverse scan
Longitudinal scan

The possibility of extrathyroidal spread should be considered: the ventral part of the nodule cannot be distinguished from the strap muscle running on the ventral surface of the lobe.

Benign lesion (cytology) - case 2026

The hypoechogenic part of the nodule has an almost identical echogenicity to the muscle fiber located at the dorsal part of the thyroid. Because the nodule is located at the dorsal border of the lobe, the borders between the nodule and the muscle fiber are indistinctive. Yellow arrows point to those part of the capsule where it is discontinuous.
Papillary carcinoma (histology) - case conp021

Yellow arrows point to that part of the image where the nodule is in contact with the strap muscle. Note the identical echogenicity of the two tissues.
Benign lesion (cytology) - case 2068

The borders between the nodule and the strap muscle (yellow arrow) are undefined. The capsule is discontinuous.
   
   
 
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