CROSS-SECTIONAL IMAGING FEATURES OF
NEOPLASTIC CONDITIONS OF PAROTID GLAND
WITH HISTOPATHOLOGICAL CORRELATION –A
PICTORIAL ESSAY.
 DR. ASHWINI G (Resident, Radiology)

DR.KARTHIK KRISHNA R (Assistant Professor, Radiology)
 DR. SEENA C .R, (Professor and HOD, Radiology)
 DR .VIMAL CHANDER R (Associate Professor, Pathology)
SAVEETHA MEDICAL COLLEGE AND HOSPITAL, CHENNAI
INTRODUCTION
 Parotid tumors affect 1 in 100,000 people representing 2-3% of tumors of head and neck
and 80% of salivary gland tumors.
 Most of these are benign with Pleomorphic adenoma being the most common, while
mucoepidermoid carcinoma is the commonest malignant lesion.
 Although ultrasonography combined with image guided FNAC is the primary diagnostic
modality, CT and MRI play an important role in evaluation of patients presenting with
suspected neoplastic lesions of parotid gland.
IMAGING FEATURES
CASE 1 – PLEOMORPHIC ADENOMA
A
B
C
32 year old female patient presented with insidious onset of slowly progressive swelling of left parotid region.
On MR imaging (A) a well defined bosselated T1 homogenous iso to hypointense mass lesion ( red arrow) and
(B) T2 homogenous hyperintense lesion seen epicentered in superficial lobe of left parotid gland .Thin rim of T2
hypointensity in the posterior aspect . (C) Post Contrast T1 fat suppressed images at the same level show near
homogenous enhancement (yellow arrow).
E
D

(D) DWI no diffusion restriction seen. With these imaging findings differentials of neoplastic lesions of
parotid namely Pleomorphic adenoma and warthins tumor were given.

This tumor turned out to be Pleomorphic adenoma on histopathology( E) which showed epithelial cells
forming tubules(black arrow) ,myoepithelial cells(yellow arrow) and chondromyxoid matrix(green
arrow).
CASE 2-WARTHIN’S TUMOUR
B
A
A
B
C
C
71 year old male patient presented with painless swelling in lower portion of the right parotid region since
four years, insidious in onset associated with history of chronic smoking.

(A) NCCT a well defined smoothly marginated slightly hyperdense lesion with internal areas of
hypoattenuation noted in the right parotid gland (red arrow). (B) Contrast enhanced CT image shows
near homogenous enhancement with internal eccentric non-enhancing area likely necrotic/cystic
component(yellow arrow). With these imaging findings differentials of neoplastic lesions of parotid
namely Pleomorphic adenoma and warthins tumor were given.

(C) On Histopathology the tumor turned out to be warthin’s tumor showing double layer of oncocytic cells
(black arrow) resting on dense lymphoid stroma(green arrow).
CASE 3-INTRAPAROTID LIPOMA
A
A
B
B
37 year old female came with swelling and pain in right parotid region for a period of 1 month
(A) NCCT a well defined hypodense lesion( red arrow) (mean HU -105 fatty attenuation) epicentered in
the superficial lobe of right parotid gland, with few internal incomplete strands/septae(yellow arrow). ( B )
Post contrast imaging showed no significant enhancement. With these imaging findings diagnosis of fat
containing benign lesion of parotid namely lipoma was given .
CASE 4-MUCOEPIDERMOID CARCINOMA
C
A
A
B
C
A 35 year old female presented with painless right parotid swelling, insidious in onset since 2 years
(A)On MR imaging a well defined T1 hypointense lesion (red arrow) and (B) T2 heterogeneously
hyperintense lesion along the superficial lobe of right parotid gland. (C) post Contrast T1 fat
suppressed images at the same level show near homogenous enhancement (yellow arrow).
D
E

(D) DWI showed diffusion restriction. With reduced diffusivity in ADC.

With these imaging findings differentials of neoplastic lesions of parotid namely atypical /degenerative
Pleomorphic adenoma /early suspicious mucoepidermoid carcinoma were given.

(E) Histopathology the tumor turned out to be low grade mucoepidermoid carcinoma showing sheets of
malignant cells (black arrow).
CASE 5 – MUCOEPIDERMOID CARCINOMA
A
B
AA
B
45 year old female with complaints of painful enlarging mass in the left cheek since 7 years with increasing in
size over past 2 months
( A ) On MR imaging ill-defined T1 heterogeneous mixed intense lesion (red arrow) involving both superficial
and deep parotid glands ( B ) T2 heterointense with small cystic areas (yellow arrow) within.
C
D

(C) Contrast medium enhancement with fat suppression shows heterogenous enhancement. (D)
Contrast enhancement noted along the pharyngeal branches of left mandibular nerve (orange arrow).
E
E
F

(E) DWI showed diffusion restriction. With reduced diffusivity in ADC.

With these imaging findings differentials of neoplastic malignant etiology like mucoepidermoid
carcinoma /adenoid cystic carcinoma were given in view of perineural involvement.

On Histopathology(F) the tumor turned out to be high grade mucoepidermoid carcinoma showing sheets of
malignant cells (black arrow) and mucoid cells(green arrow).
CASE 6-ADENOID CYTSIC CARCINOMA.
A
A
C
B
C

46 year old female who presented with painless swelling in right side of the face since 7 months with
rapid increase in size over past 1 month

(A) a fairly defined lesion T1 hypointense lesion(red arrow) in the right parotid region predominantly
involving the superficial lobe. (B) and T2 isointense lesion. (C) Post contrast at the same level shows
heterogenous enhancement with central non-enhancing necrotic/cystic component(yellow arrow).
D
EE

(D) DWI image shows peripheral diffusion restriction.

With these imaging findings differentials of neoplastic malignant etiology like mucoepidermoid carcinoma
/adenoid cystic carcinoma were given.

On histopathology (E) showed tumor cells arranged in cribriform and tubular architecture(black arrow) in
consistent with a low grade variant of adenoid cystic carcinoma.
CASE-7- CARCINOMA EX PLEOMORPIC ADENOMA
A
B
AA
C
B
C

A 72 year old male with presenting complaints of expanding painful left sided soft tissue swelling of face since
3months

(A) On NCCT an ill-defined heterodense lesion with irregular margins (red arrow) involving both superficial and
deep lobes with (B) post contrast images showing heterogenous enhancement with central non-enhancing
necrotic area (yellow arrow).

On Histopathology (C) tumor cells arranged in papillary and glandular pattern(black arrow) lined by Pleomorphic
nuclei was seen which was consistent with carcinoma ex Pleomorphic adenoma .
CASE-8 METASTATIC SQUAMOUS CELL CARCINOMA
A
A
B
B
C
C
A 67 year old male came with history of primary malignant lesion of soft palate and uvula came with
complaints of left parotid swelling
 (A) NCCT a fairly defined heterogeneous lesion (red arrow) in left parotid gland with (B) post contrast
heterogenous enhancement (yellow arrow)with significant non-enhancing areas within seen.
 On Histopathology(C) this lesion showed sheets of malignant cells(green arrow) with keratin pearl
formation(black arrow) turned out to be moderately differentiated infiltrating squamous cell carcinoma.
CONCLUSION
 Even though the parotid neoplastic lesions present with similar clinical history they
present with varied pathological and imaging features.
 The exact pre-operative evaluation of parotid gland neoplasms remain a major
challenge(1).
 Cross –sectional imaging plays an important role in characterising the lesions.
 However MRI is superior to CT in assessing the extent of tumor and invasion of
neighbouring structures and perineural spread(1).
Acknowledgements
To my professors
 1.DR.SEENA.CHEPPALARAJAN
 2.DR.PAARTHIPAN NATARAJAN
 3.DR.MUTHIAH PITCHANDI
 4.DR.PRAVEEN SHARMA
To my assistant professor for guiding and helping
 5.DR.KARTHIK KRISHNA
 Department of pathology for deciphering the histopathological
slides
 Department of surgery and ENT for clinicalsurgicalreferral
history.
REFERENCES
1.Thoeny HC. Imaging of salivary gland tumours. Cancer Imaging. 2007;7(1):5262. Published 2007 Apr 30. doi:10.1102/1470-7330.2007.0008
2.