Salivary Gland Tumors
Sasan Dabiri, M.D. - Assistant Professor
Department of Otorhinolaryngology – Head & Neck surgery
Amir A’lam hospital
Tehran University of Medical Sciences
Epidemiology
• Overall prevalence:
– 3% of Head & Neck neoplasms
– 100 parotid neoplasms
– 10 submandibular neoplasms
– 10 minor salivary gland neoplasms
– 1 sublingual neoplasm
Salivary Gland Tumors
Epidemiology
• The most common neoplasms:
– Benign in anywhere:Pleomorphic Adenoma
– Malignant in parotid:Mucoepidermoid Carcinoma
– Malignant in others:Adenoid Cystic Carcinoma
– Post radiation, benign: Warthin’s tumor
– Post radiation, malignant: Mucoepidermoid Carcinoma
Salivary Gland Tumors
Fine Needle Aspiration / Biopsy
• Goals are:
– Differentiation of neoplastic and non-neoplastic mass
– Differentiation of benign and malignant neoplasm
• High specificity (96-98%)
• Good sensitivity (79-96%)
Salivary Gland Tumors
Fine Needle Aspiration / Biopsy
• Is it Accurate?
– Highest inaccuracy rates in Parotid
• Diversity in pathology ( 11 benign & 24 malignant )
• Other than mixed tumor, are uncommon
• Morphologically complex
• Some carcinomas have not malignant cellular appearance
Lower accuracy for diagnosing malignant tumor
Salivary Gland Tumors
Frozen Section
• Indications :
– Determination of tumor extension
– Evaluation of surgical margin
– Non-diagnostic FNA
– Incompatible FNA according to clinical judgement
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
Salivary Gland Tumors
Imaging
• Differentiation of benign and malignant tumors is not the primary goal of CT and MRI; but:
– Anatomical localization
– Local, Regional (lymph node), and Distant invasion
• Overall
– Low intensity in T1 & T2 malignant (high probable)
Salivary Gland Tumors
Imaging
• Why MRI is better than CT?
– Well visualized on T1 (especially parotid “fatty gland”)
• Excellent assessment of margins
• Deep extension & Infiltration
– Best mapping on T1+ Gd + Fat suppression• Bone marrow & cortex: hyposignal
invasion, well visualized
• Fatty & bony foramina at skull base: hyposignal
perineural spread: well visualized
• Meningeal invasion
Salivary Gland Tumors
Imaging
• Perineural invasion for parotid tumor
– Facial nerve
• entire nerve should be assessed all the way
( even if there is no clinical facial paralysis )
– Auriculotemporal nerve
• through a small fat pad along the
medial aspect of the lateral pterygoid muscle and just inferior to the foramen ovale
Salivary Gland Tumors
Imaging
• Perineural invasion for submandibular tumor
– Hypoglossal nerve
• Tongue movement impairment
– Lingual nerve
• Tongue tingling
Salivary Gland Tumors
MRI visualizes :• enlarged nerve• obliterated fat• enlarged ganglion• atrophy of the masticator muscles
Imaging
• Radionuclide Scanning (Tc 99m)
–Warthin’s tumor
– Oncocytoma
Salivary Gland Tumors
Helpful for elderly patients with parotid mass
Aldred Scott Warthin1866 - 1931
Imaging
• Ultrasonography
Pros
– Differentiation of glandular from extraglandular mass
– Guiding the biopsy (FNA)
Cons
– Operator dependent
– Just in superficial masses
Salivary Gland Tumors
Pleomorphic Adenoma
Salivary Gland Tumors
• Epithelial and
Mesenchymal
components
• 10% risk of
malignancy after
15 years
Warthin’s tumor
Salivary Gland Tumors
• Papillary Cystadenoma Lymphomatosum
• Only in parotid
• Male & cigarette smoking
• No risk of malignancy
• bilateral
Mucoepidermoid Carcinoma
Salivary Gland Tumors
• Contains mucoid
and epidermoid cells
• Low, intermediate
and high grade
classification
Adenoid Cystic Carcinoma
Salivary Gland Tumors
• Perineural invasion
• Grading according
dominant cells:
• Cribriform
• Tubular
• Solid
Management
• Surgery
– primary management in all new and recurrent cases
Unless :
• Surgery cannot be done (patient’s condition)
• Invasion to skull base
• Invasion to pterygoid plates
• Encase carotid artery
Salivary Gland Tumors
T4b
Management
• Radiation therapy ± Chemotherapy
– Unable to surgery
– Adenoid cystic carcinoma
– Intermediate or high grade carcinoma
– Close or positive margin
– Perineural or perivascular invasion
– Lymph node metastasis
Salivary Gland Tumors
In cases with complete resection
Thanks for Your Attention