Salivary Gland Tumors Flashcards
What is the innervation to the parotid gland
Parasympathetic: CN 9
Sympathetic: superior cervical ganglion
What and where is stensen’s duct
Parotid duct
- located 1/2 b/w Zarch and angle of mouth
- courses anterior to masseter, pierces buccinator and enters oral cavity at 2nd maxillary molar
Where are the submandibular and sublingual glands located and their ducts
Submandibular: occupies space between two digastric bellies and inferior to mandible border
- mainly lies superficial to mylohyoid but also has deep lobe that lies between mylohyoid and hyoglossus muscles
- Warthins duct, 5cm in length, courses from posterior (deep lobe) along FOM, crossign CN 12 and lingual n to exit at frenulum
Sublingual gland
- lies immediately deep to FOM mucosa at anterior tongue, above genioglossus, behind mandible
- Rivinus and bartholins duct open direct into FOM or into warthins duct
What is the innervation to the sunlingual and submandibular glands
- Parasympathetic: Cn 7
- Sympathetic: superior cervical ganglion
What is the epidemiology of SGT?
- 80% of SGT are in the parotid, 15% submandibular, 5% minor
- 80% are benign
- of the malignant tumors, the majority are in minor salivary glands = the samller the gland, the more likely its malignant
- Most common parotid tumor: Pleomorphic adenoma
- most common submandibularminor tumor: Adenoid cystic Ca
- most common malingnat parotid tumor Mucoepidermoid Ca
What are RFS for developing SGT
Radiation exposure (10-30yr delay)
Also potentially smoking (warthins) EBV
What is your differential Dx for a mass in a Salivary gland
NEOPLASTIC
Benign
- Pleomorphic Adenoma
- Warthins
- oncocytoma
Malignant
- Mucoepidermoid Ca (can be low grade)
- Adenoid Cystic Ca (low grade)
- Adenocarcinoma
- Acinic cell Ca
- Carcinoma Ex-Pleomorphic adenoma
- SCC
INFLAMMATORY
- inflammation, acute, chronic
- sialocele
- sialodenosis
- granulomatous disease (sarcoid)
INFECTIOUS
- TB, cat scratch
What is your DDX for infiltrative process of Salivary gland
- Sarcoid
- Sjogrens
- Sialodenosis
- inflmmation
- Sialolithiasis
What is your managmeent
History
- MASS - growth pattern, tenderness,
- nasal/sinus obstruction (minor glands)
- constitutional
- CN7 involvement
Physical
- MASS - mobility, invasion to adjcent structures
- lymphadenopathy
- bimanual palpation of each SG
- CN 7 exam
Investigation
- U/S
- CT
- FNA/core biopsy
- CXR - lung mets
What i syour treatment of benign vs malignant lesions
Benign
- Parotid - superficial parotidectomy - no scarifice of CN7, no ND
- Submand/sublingual/minor - simple excision
Malignant
- depends on tumor grade, size, type
- Total parotidectomy +/- CN7 resection (only is preop paralysis or intraop gross disease)+ nerve graft/static sling +/- ND +/- Rtx
- ND if + clinical/radiologic
- If node negative, ND elective for T3/4, high grade adenoCa, salivary duct CA, SCC
- Rtx if T3/4
What is a pleomorphic adenoma
Benign mixed tumor - epithelial and myoepithelial
- usually in tail of parotid
- 7% risk of degeneration into Carcinoma Ex-plemorphic adenoma
Tx - superficial parotidectomy
What is warthins tumor
Papillary cystadenoma Lymphomatosum
- 10% bilateral, in tail, ass. w smoking
- 2nd most common parotid tumor
What is mucoepidermoid carcinoma
Most common malignant parotid tumor
- Low grade or high grade
- high grade high risk of LN mets
- 2nd most common submandibular/minor gland tumor behind adenoid cystic ca
What is adenoid cystic ca
Most common malignant tumor of submandibular/minor glands
- high risk of perineural/vascular invasion
- high risk of lung mets
- Tx - WLE + post op Rtx
What tumors metastasize to the parotid
- Melanoma of the H&N, Trunk
- SCC of the H&N
- lung
- breast
- renal
- prostate
- GI
What are methods of identifying the main trunk of the facial nerve
- Via Tragal pointer
- in preauricular portion of incision, seperatio of parotid fascia and ECA reveals tragal pinter. 1-1.5cm deep and inferior is located manin trunk
- Via tympanomastoid suture
- 6-8mm lateral to stylomastoid foramen is located TM suture. From suture, main trunk is located 6-8mm deep to suture
- Retrograde tracing
- identification of terminal facial branches and tracing branches to main trunk
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- identification of terminal facial branches and tracing branches to main trunk
Describe steps for parotidectomy
- Modified Blair incision - preauric from root of helix, to lobuel, posterior to mastoid, then traced along anterior border of SCM til 2 fingerbreadth below mandible
- lift preauric skin flap superficial to parotid fascia and neck flap in subplatysmal plane
- ID GAN EJV along SCM and liekly needed to be divided
- once reached patorid, identify main trunk and trace out. Resect all gland above CN7 (superficial parotidectomy)
Describe excision of a submandibular gland
- Incision 3-4fingerbreadth below mandible, at inferior edge of submandibular gland
- incise though platysma, identify facial vein and ligate, lift superioly, and this will protect marginal br
- ligate facial artery to free superior attachment of gland
- mylohyoid vessels divided and muscle retracted anteriorly and submandibular gland pulled posteriorly to expose deep portion of gland
- Submandibular duct, submandibular ganglion, lingual n, CN12 nerves identified lying on top of hyoglossus
- longual n br to gland trasnected and facial art dvided second time
What is frey syndrome and treatment
Aberrant reinnervation of ATN - parasympathetics to parotid gland and sympathtics to scalp sweat glands cross innervate and results in gustatory sweating
Tx
Non-op
- scopolamine topical/oral
- glycopyrrolate
- botox
Operative
- skin excision, dermal/fat interposition graft/ADM, TPF
