Wk 9, Case 3 - Review

Patient History
Left parotid mass

Findings
Pre- and postcontrast MR was performed of the brain and parotid gland.

Brain: Sagittal T1-weighted images demonstrate corpus callosum to be intact. No evidence of Chiari malformation. No abnormal pineal region masses. Pituitary gland is not enlarged. Diffusion imaging demonstrates no evidence of recent infarct. Axial FLAIR and T2 weighted images show prominence of the sulci and ventricles. No evidence of vasogenic edema or mass effect. Contrast-enhanced T1 weighted images show no abnormal intraaxial or extraaxial enhancing masses. Mucosal thickening involving multiple ethmoid sinuses and right maxillary sinus. There is an approximately 1.3cm pedunculated left scalp lesion overlying the left occipital bone.

Parotid Gland: Thin-section pre- and postcontrast MR was performed through the parotid glands. There is approximately 1.9cm x 1.4cm mass involving the superficial lobe of the left parotid gland. This lesion is intermediate signal on T1 and may mildly enhance. The lesion is low signal on T2. These findings indicate a solid lesion or a mass that contains high protein. The deep extent of this dominant mass appears to be superficial to the right retromandibular vein and lateral to the expected location of the pes anserinus. The superficial extent of the lesion appears to be deep to the paritidomassteric fascia. There is a similar appearing 8mm lesion involving the tail of the left parotid gland.

There is also a similar 9mm lesion involving the anterior aspect of the tail of the right parotid gland and a 1.2 mm lesion involving the anterior aspect of the midportion of the right parotid gland which is subcapsular in location. These findings are atypical for normal intraparotid lymph nodes with a more typical appearing left pretracheal lymph node that contains fat, best seen on image 16 of series 8.

There are prominent bilateral postglandular level 1 lymph nodes that measure approximately 2cm on the right and 1.7cm on the left which are best appreciated on the coronal images.

Conclusions
1. Multiple intraparotid lesions with the largest being approximately 1.9cm x 1.4cm involving the superficial lobe of the left parotid gland. Given these lesions are multiple and bilateral, one must consider the possibly of Warthin's tumors. Oncocytosis is a possibility but less likely. The lack of avid enhancement makes systemic processes such as lymphoma or metastases less likely, but would be included in the differential diagnosis. Other rheumatologic disorders can also present with bilateral enlarged intraparotid nodes such as Sjogren's disease.
2. No abnormal intraaxial enhancing masses.
3. Approximately 1.3cm pedunculated left scalp lesion overlying the left occipital bone.
4. Prominent bilateral postglandular level 1 lymph nodes that measure approximately 2cm on the right and 1.7cm on the left which are best appreciated on the coronal images and could be related to systemic processes that could result in the parotid lesions.