salivary gland diseases

浙江大学医学院附属第二医院口腔颌面外科浙江大学医学院附属第二医院口腔颌面外科Dept. Oral Maxillofac. Surg., Second Affiliated Hospital, ZJUDept. Oral Maxillofac. Surg., Second Affiliated Hospital, ZJU

Salivary gland diseases

Dr. Yanming LiuDept. Oral & Maxillofacial Surgery

2nd Affiliated Hospital, ZJU


Section 1: Clinical anatomy

Submucosal minor salivary glands: labial, buccal, palatal, lingual

Three paired major salivary glands:

• Parotid gl.• Submandibular gl.• Sublingual gl.


Parotid gland largest almost entirely serous between ramus of the

mandible, mastoid process, external acoustic meatus, SCM muscle,

Pyramidal in shape Superficial and deep

lobes by facial nerve and branches

Stenson’s duct, its opening opposite 2nd upper molar

Adjacent structures: facial n., external carotid a., retromandibular v.


Submandibular glands Submandibular gl.: • Intermediate in size• A seromucous

(predominantly serous) gland

• Superficial and deep parts

• Hooked in shape• Wharton’s duct, its

opening: sublingual papilla

• Adjacent structures: facial artery/vein, marginal mandibular branch of facial n., lymph nodes, lingual and hypoglossal n.


Sublingual glands Sublingual gl.: • Smallest• seromucous, but

predominantly mucous

• above mylohyoid m., the sublingual fossa

• Adjacent structures: lingual and hypoglossal n.; deep lingual a./v.

• Open direct to the oral cavity or through Wharton’s duct


Physiology of salivary glands Functions of Saliva• lubricates food • moistens oral mucosa • digestive enzymes • antimicrobial agents,

e.g. immunoglobulin A (IgA)

• Xerostomia may result in periodontal inflammation and dental caries

Data about saliva• 0.5 L saliva / day • 0.3 mL/min when

unstimulated, • 1.5–2 mL/min when

stimulated • Unstimulated state:

parotid gl. contributes 20%, submandibular gl. 65%, other 15%.

• When stimulated, parotid contribution rises to 50%.


Section 2: Investigations


Investigations History taking: swelling, pain,

mass, nerve functions, etc. Clinical examination: • bimanual palpation; • comparing bilateral glands Auxiliary examination:• Radiology (plate radiography, CT,

MR, PET/CT)• Ultrasound• Biopsy • Sialometry


Symptoms and their indication

Symptom Suggestion

Slowing developing swelling or mass

tumor

Immediate swelling at meal, then slowly subsiding

Obstruction by calculus

Pain and swelling, perhaps with bad taste

Infection

Dry mouth Sjogren’s syndrome

Facial nerve palsy with a mass in parotid gland

Malignant tumor?


Sialometry

Method: volume of saliva dribble over 5 minutes at the unstimulated condition

Normal saliva flow rate: 0.3-0.4ml/min Clinically significant xerostomia: <0.1ml/min


Clinical situation and auxiliary test option

Clinical situation Selection

Calculus present? Plain radio.; Ultras.

Obstruction in the duct system?

Sialography

a mass present? Ultrasound, CT, MR

Abnormal gland function? Radioisotope imaging

Evaluation of salivary function

Labial minor gland biopsy


Biopsy in salivary gland disease

Clinical situation Selection

Evaluation of overall salivary function

Labial minor gland biopsy

Tumor of major glands No incisional biopsy!!!;

Fine needle aspiration biopsy

Frozen section


Section 3: salivary gland diseases


3.1 obstructive salivary disorders

Caused by narrowing or total obstruction of ductal system

Typical symptoms: pain and immediate swelling of the affected gland just before meal, or having meal, or maybe thinking about meal, which then slowly subside after meal.

Occasionally accompanied by a bad taste, indicating associated sialadenitis.



Three types: Extraductal obstruction, e.g.

neoplasia duct wall thickening, caused by

trauma or fibrosis intraductal obstruction (most

common type) , caused by calculi (sialoliths), 80% in submandibular gland



Why do intraductal obstruction and sialolithiasis happen more often in submandibular gl. (80%) than parotid gl.?

Submandibular gl. Parotid gl.

Mucoserous saliva Almost serous saliva

Containing more calcium salt Less calcium salt

Saliva flows upwards, against gravity

Nearly horizontally



Treatment options of intraductal obstruction by sialoliths:

Antibiotic and anti-inflammatory treatment Remove sialolith by marsupialization of the duct,

when sialolith is close to the wharton’s papilla. Remove sialolith with the assistance of

sialendoscopy Remove the submandibular gland and the sialolith

when it is close to the gland, especially with fibrosis of the gland.


3.2 acute viral sialadenitis Also named mumps, acute contagious infection, caused by

paramyxovirus through direct contact with infected saliva Incubation period of 2-3 weeks Fever, malaise Sudden and painful swelling of one or both parotid gl. (occasionally

submandibular gl.) clear salivary secretion Occasionally involvement of central nerve system and gonads (orchitis),

in rare case resulting in dysgenesis Lifelong immunity Rising hemodiastase and urinary amylase in some cases Treatment: bedrest, massive water drinking, fluid infusion, antiviral

treatment, etc. Avoiding the infected patients to contact with susceptible population


3.3 acute bacterial sialadenitis Principally involving parotid gl. (parotitis) Etiological factors: • Local: reduced salivary flow leading to bacteria in the ductal

system; mainly by staphylococcus aureus• Systemic: other chronic diseases or large surgical operation,

leading to poor systemic conditions; fluid and electrolyte imbalance

Often unilateral parotid gl., pain and swelling Red and swelling of duct opening, mucopurulent discharge fever, erythema of skin Treatment principles:• supporting therapy: bedrest; water drinking or fluid infusion,

correction of electrolyte imbalance• antibiotic therapy; mouthrinse• Incision and abscess discharge when pitting edema and

tenderness, or when getting pus by needle aspiration or confirmed by ultrasound


3.3 chronic bacterial sialadenitisCaused by low-grade bacterial invasion, often

follows chronic obstructive diseaseSubmandibular gland most commonly

involvedSymptom: recurrent and painful swelling

associated with eating and drinkingSalty and bad tasteMucopurulent dischargeCan be transformed into acute sialadenitisTreatment: removal of sialolith, mouthwash,

removal of gland when fibrosis


3.4 radiation sialadenitis

History of radiotherapy for head and neck cancers Acinar damage and fibrous replacement Low saliva secretion, leading to dental caries and

mucositis Prevention: shielding the salivary glands when

radiotherapy Treatment of xerostomia (dry mouth)


3.5 Sjögren’s syndrome

Autoimmune chronic inflammatory disease involving salivary and lacrimal glands

Characterised by polyclonal B-cell proliferation Continuous destruction of glandular parenchyma

and lymphocytic infiltration Classification: • primary Sjögren’s syndrome • secondary Sjögren’s syndrome



Primary Sjögren’s syndrome • Xerostomia (dry mouth) and xerophthalmia (dry

eyes) (and nasal, vaginal, skin ... dryness) Secondary Sjögren’s syndrome• Xerostomia (dry mouth) and/or xerophthalmia (dry

eyes) • an autoimmune connective tissue disease

(Rheumatoid disease, renal tubular acidois...)



Clinical features• Mostly involving middle-aged females• Symptoms of xerostomia including: glazed oral

mucosa; lobulated beefy-red tongue; difficulty in eating dry foods, swallowing, speaking, etc.

• Parotid gland enlargement, occasional acute infection

• Symptoms of xerophthalmia



Valuable tests in aiding in diagnosis• Sialometry (salivary flow rate measurement)• Schirmer test (lacrimal flow measurement)• Detection of autoantibodies against SS-A, SS-B,

RF (rheumatoid factor), etc. • Labial gland biopsy: infiltration of lymphocytes

around intralobular ducts, resulting in focal lymphocytic sialadenitis



Management• Multidisciplinary team• Management of xerostomia Salivary stimulants (sugar-free gum, pilocarpine) if residual

salivary function remains

Saliva substitutes

Prevention of caries and periodontal disease


3.6 salivary gland tumors

3% of human tumorsMostly arising in the parotid gland (80%), in

which 90% are benignHigher relative proportion of malignant

tumors in submandibular (40%), sublingual (90%), palatal and other minor glands (60%)


3.6 salivary gland tumors

Common benign salivary gland tumors• Pleomorphic adenoma• Wharthin’s adenoma

Common malignant salivary gland tumors• Adenoid cystic carcinoma

• Mucoepidermoid carcinoma


3.6.1 Pleomorphic adenoma

Benign Accounting for 80-90% of all

salivary tumors Slow-growing, painless nodule,

soft or firm in texture, moveable, well-circumscribed

Varied size ( several cm to ~20 cm) and duration ( several months to decades)

Rare involving facial nerve Low potentiality of canceration


3.6.1 Pleomorphic adenoma Also termed “ mixed tumor” Characteristic cellular and

stromal elements Celluar element: ductal

epithelial and myoepithelial cells

Stromal element: myxoid (muscle-like) tissue or chondroid (cartilage-like) tissue

Tumor islands may exist beyond capsule

Management: excision biopsy of tumor together with a margin of normal tissue


3.6.2 Wharthin’s tumour Also termed “adenolymphoma” benign Predominantly in older men and

exclusively in parotid Discrete nodule, smooth, soft in

texture, mostly <3cm in diameter Etiologically related to smoking Can be multiple nodules and in

bilateral parotids Characteristical pathological

feature: a papillary cystic structure composed of double layered ductal cells and a lymphoid stroma


3.6.2 Wharthin’s tumour

Management: tumor excision, when multiple nodules present, excision the surrounding glandular tissue as well


3.6.3 adenoid cystic carcinoma

Middle-aged or elderly patients Frequently in palatal minor gland

and parotid Slow growing, tendency to invade

and spread along nerve, leading to pain, palsy or paraesthesia

Histopathologically “Swiss-cheese”-like structure due to microcysts filled by basement membrane material

Infiltrative, metastasis Poor long-term prognosis Treatment: surgery with adjuvant

radiotherapy; involved nerve has to be sacrificed

Perineural invasion


3.6.4 mucoepidermoid carcinoma

Younger and Middle-aged patients

Histopathologically both mucous and squamous differentiation

Painless slow-growing nodule; blue “cyst”

Treatment:• high differentiation: surgery,

preserving nerve• low differentiation: surgery

with radiotherapy


3.6.5 salivary gland cysts Blue, fluctuant swellings, with a

relapsing history Mucous extravasation mucocele• Tearing of the duct due to trauma,

leading to leakage of saliva into the connective tissue;

• No epithelium lining;• Major type, mainly in low labial mucosa,

buccal mucosa, sublingual gland (ranula)

Mucous retention mucocele• Duct expansion, leading to cyst with

epithelium lining• Mostly in upper labial mucosa


3.6.5 salivary gland cystsTreatment: removal of cyst as well as the minor

gland or sublingual gland


A case of giant cancerized pleomorphic tumor

Slow growth of the tumor for 34 years, painful recently


A case of giant cancerized pleomorphic tumor Slow growth of the tumor for 34 years, painful recently


A case of giant cancerized pleomorphic tumor

salivary gland diseases

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