PMC9249508_01
Imaging of the right parotid gland. (a) CT with contrast demonstrating increased soft tissue density. (b) MRI demonstrating mass-like enhancement. (c) Ultrasound demonstrating a poorly defined nodule.
CRIPA2022-5687190.001.jpg
PMC9249508_01_CRIPA2022-5687190.001.jpg
fig1
CT with contrast revealed a focus of increased soft tissue density in the right parotid gland just lateral to the mandibular subcondylar region measuring 1.3 cm (Figure 1(a)). Inflammation and enlargement of the facial nerve was also noted (Figure 1(b)). Ultrasound showed an ill-defined hypoechoic nodule near the angle of the mandible/preauricular area (Figure 1(c)).
(a) Biopsy of the parotid gland revealed a neoplasm comprised of atypical cells in a fibromyxoid stroma (H&E*, 400x). Resection of the parotid mass. (b) Tumor infiltrating adjacent tissue (H&E*, 20x). (c) Tumor is comprised of atypical cells in small clusters with occasional intracytoplasmic vacuoles and foci of cytologic pleomorphism (H&E*, 400x). (d) Perineural invasion (H&E*, 100x). *Hematoxylin and eosin.
CRIPA2022-5687190.002.jpg
PMC9249508_01_CRIPA2022-5687190.002.jpg
fig2
Subsequent biopsy showed atypical cells embedded in a mostly myxoid background, highly suggestive of EHE (Figure 2(a)). Multiple foci of perineural invasion were identified; however, lymphovascular invasion and tumor necrosis were not seen (Figures 2(b)-2(d)).
Positive immunohistochemistry for (a) CD31 and (b) ERG (100x).
CRIPA2022-5687190.003.jpg
PMC9249508_01_CRIPA2022-5687190.003.jpg
fig3
CD31, and CD34 (Figures 3(a)-3(b)). Cytokeratin AE1/AE3 was negative.