case_images: PMC5346937_01
case_images: Sonograms of the left neck in the transversal (a) and longitudinal (b) planes showing a hypoechoic mass. The mass (arrowheads) showed a relatively regular border, enhanced back echoes, and dissimilar internal echoes. c Computed tomography showing an enhanced lesion (arrowheads) in the left upper neck in contact with the carotid bifurcation and the jugular vein. d Positron emission tomography/computed tomography (PET-CT) revealed FDG avidity in the left-sided neck at a level II lymph node. There was no evidence of a primary lesion including the parotid and submandibular glands on PET-CT.
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case_images: f1
case_images: Back echoes were enhanced, and internal echoes were dissimilar (Fig. 1a, b). Computed tomography showed an enhanced lesion in the left upper neck in contact with the carotid bifurcation and the jugular vein (Fig. 1c). There was no evidence of a primary lesion, including the parotid and submandibular glands, on PET-CT (Fig. 1d).
case_images: a The gross resected specimen was yellow-white in color and formed lobular nodules involving a level II lymph node in the left-sided neck. b, c HE staining of the tumor revealed various cell populations, including a solid proliferative component (b) and tubular and papillary-cystic structures (c). The papillary-cystic lesion (c) included many microcystic structures in the component cells. Scale bars, 500 microm (b); 100 microm (c).
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case_images: PMC5346937_01_cro-0010-0192-g02.jpg
case_images: f2
case_images: The gross resected specimen was yellow-white in color and formed lobular nodules (Fig. 2a). The tumor consisted of tubular structures containing secretion, papillary-cystic structures, and a solid proliferative component (Fig. 2b). The papillary-cystic lesion showed many microcystic structures in the component cells (Fig. 2c).
case_images: a-c Immunohistochemical staining showed that the neoplastic cells were negative for DOG1 (a) but positive for S100 protein (b) and GATA3 (c). Scale bars, 50 microm (a-c). d A fluorescence in situ hybridization study with an ETV6 (12p13) break apart probe revealed green (small arrow) and red split signals (large arrow), indicating a break in the ETV6 gene.
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case_images: PMC5346937_01_cro-0010-0192-g03.jpg
case_images: f3
case_images: Immunohistochemical staining showed that the neoplastic cells were negative for p63 and DOG1 (Fig. 3a) but were positive for S100 protein (Fig. 3b) and GATA3 (Fig. 3c). A fluorescence in situ hybridization (FISH) study with an ETV6 (12p13) break apart probe revealed split signals in 95% of the nuclei (Fig. 3d).