PAROTID GLANDS - Chennai City Branch Of ASI

Download Report

Transcript PAROTID GLANDS - Chennai City Branch Of ASI

Dr.K.Kuberan M.S
Professor of surgery
Govt.Royapettah Hospital
 Largest
salivary
glands lying largely
below the external
acoustic meatus
between mandible
and
sternocleidomastoid
muscle and it also
projects forwards on
the surface of
masseter
Ectodermal in origin
 Each parotid is developed during
5th week from angle of primary
oral fissure.
 The groove is converted into tube
which forms duct and opens into
angle of primitive mouth.

With the growth of maxillary and
mandibular process the duct
opening is shifted to vestibule
opposite the upper 2nd molar
tooth.
 During development the gland lies
in between the branches of facial
nerve, as development progresses
it envelopes the branches.

 Superficial
part(80%)lies over
posterior part of ramus of
mandible
 Deep part(20%) lies behind
mandible and medial pterygoid
 Facial nerve lies between them
 The
gland has a capsule of its
own of dense connective
tissue but is also provided
with a false capsule by
investing layer of deep
cervical fascia.
Skin
 Superficial fascia
 Superficial lamina of investing
layer of deep cervical fascia
 Great auricular nerve (anterior
ramus of C2 and C3)

 Mandibular
ramus,
 Masseter and medial
pterygoid muscles
•
•
•
Mastoid process
Styloid process
Carotid sheath with its contained
neurovasculature (Common and
Internal Carotid artery, Internal
Jugular vein, vagus nerve)
 Superior
pharyngyeal
constrictor muscle
From lateral to medial
 Facial nerve
 Retromandibular vein (Patey's
fascio venous plane)
 External Carotid artery
 External
carotid artery
 Retromandibular vein
 Superficial
and deep group
of parotid lymph nodes.
 Efferents from these nodes
drain into jugulodigastric
group of deep cervical
nodes
 Parasympathetic
– stimulates
watery secretion
 Sympathetic – stimulates
mucus rich thick secretion
and also vasomotor
Also known as Stensen’s duct
 Appears at the anterior part of
upper border of gland and passes
across masseter to traverse
buccal fat and buccinator.
 Runs obliquely forwards for a
short distance between
buccinator and the oral mucosa
and opens upon a small papilla
opposite upper 2nd molar tooth.

 Infections
•
•
–
Very painful due to
unyielding nature of capsule.
Retrograde bacterial infection
may occur from mouth via
duct.







Viral – mumps, coxsackie A & B,
parainfluenza 1 & 3
Bacterial – staphylococcus
aureus,streptococcus viridans
Poor oral hygiene
HIV
Radiotherapy
Syphilis
Sjogren’s syndrome
Painful diffuse swelling
 Fever,malaise
 Warmth, Tender
 Regional lymph node enlarged

 Caused
by paramyxovirus
 Incubation period 2-3 weeks
 Bilateral 90%
 Common in children
 Clinical features:Fever
Swelling
Pain, tender
 Orchitis
 Oophoritis
 Pancreatitis
 Meningoencephalitis
Ultrasound
 Calculous
 Abscess

Meticulous oral hygiene
 Analgesics
 Antibiotics
 Soft diet
 Parotid abscess-I&D (Hiltons
method)







Age 3-6yrs
Recurent episode of pain
Diffuse swelling
Fever
Enlarged lymph nodes
Spontaneus resolution







In Adults
Calculous- Unilateral
Auto immune-Bilateral
Diffuse swelling
Pain
Purulant saliva
Pressure on sialectic gland may express pus
from the duct.
 Xray
Plain films are not much useful since parotid
stones are radiolucent.
 Sialography
 Punctate sialectasis(snowstorm)appearance

Extraction of stone through oral
cavity
 Conservative parotidectomy if
multiple calculi

 ADENOMA
pleomorphic -pleomorphic adenoma
 monomorphic-warthin’s tumor
Oxyphilic adenoma
 CARCINOMA (low grade) :
 acinic cell carcinoma
 adenoid cystic carcinoma
 low grade mucoepidermoid

High grade
adenocarcinoma
squamous cell carcinoma
high grade mucoepidermoid carcinoma
 Non epithelial tumors
haemangioma
lymphangioma

 Lymphomas
primary- non-hodgkin’s
secondary- lymphoma in sjogren’s
 Secondary tumors
 Unclassified tumors
 Tumor like lesions
solid lesions
cystic lesions
RULE OF 80
 80% of salivary neoplasms are of
parotid origin
 80%

of parotid masses are neoplastic
80% of neoplasms in parotid are benign

Intercalated Ducts
◦
◦
◦
◦
◦
Pleomorphic adenoma
Warthin’s tumor
Oncocytoma
Acinic cell
Adenoid cystic

Excretory Ducts
◦ Squamous cell
◦ Mucoepidermoid




Striated duct—oncocytic tumors
Acinar cells—acinic cell carcinoma
Excretory Duct—squamous cell and
mucoepidermoid carcinoma
Intercalated duct and myoepithelial
cells—pleomorphic tumors








Most common parotid neoplasm
Median age—Fifth decade
Common in females
Usually unilateral
Slow growing mass(80%)
Lobular
Not well encapsulated
Malignant degeneration (2-10%)









Mobile
Nontender
Firm
Solitary mass in parotid region
Raised ear lobule
Obliteration of retromandibular groove
Cannot be moved above zygomatic bone
Deviation of uvula & pharyngeal wall towards
midine if deep lobe involved
No facial nerve involvement

Greyish white in
color with
possible cyst
formation and
haemorrhage.
Mixture of epithelial,
myoepithelial and stromal
components
Epithelial cells:
nests,sheets, ducts,
trabeculae
 Stroma:
myxoid, chrondroid,
fibroid, osteoid
No true capsule
Tumor pseudopods
Arise from deep lobe
Swelling in the lateral wall of pharynx
Soft palate displaced to opposite side







Rapid increase in size
Pain and nodularity
Involvement of skin & ulceration
Involvement of masseter
Involvement of facial nerve
Involvement of neck lymph node





2-4% of all salivary gland neoplasms
4-6% of mixed tumors
6th-8th decades
Parotid > submandibular > Minor
salivarygland
Risk of malignant degeneration
 1.5% in first 5 years
 9.5% after 15 years

Presentation
 Longstanding painless mass that undergoes
sudden enlargement

Histology
• Malignant cellular
change adjacent to
typical pleomorphic
adenoma
• Carcinomatous
component:
 Adenocarcinoma
 Undifferentiated
Second most common benign parotid
tumour (5%)
 Most common bilateral benign
neoplasm of parotid.
 Common in lower pole
 Slow-growing, painless mass
 Marked male predominance
 Sixth and seventh decade
 Hot spot in Tc99 scan
 Malignant transformation rare.

◦ Encapsulated
◦ Smooth/lobulated
surface
◦ Cystic spaces of
variable size,
with viscous
fluid, shaggy
epithelium
◦ Solid areas with
white nodules
representing
lymphoid follicles
◦ Papillary projections
into cystic spaces
surrounded by lymphoid
stroma
◦ Epithelium: double cell
layer
 Luminal cells
 Basal cells
◦ Stroma: mature
lymphoid follicles with
germinal centers

May represent heterotopic salivary
gland epithelial tissue trapped within
intraparotid lymph nodes






Rare: 2.3% of benign salivary tumors
6th decade
M:F = 1:1
Parotid: 78%
Submandibular gland: 9%
Presentation
◦ Enlarging, painless mass


Gross
◦ Encapsulated
◦ Homogeneous, smooth
◦ Orange/rust color
Histology
◦ Cords of uniform cells and thin
fibrous stroma
◦ Large polyhedral cells
◦ Distinct cell membrane
◦ Granular, eosinophilic
cytoplasm
◦ Central, round, vesicular
nucleus

Electron
microscopy:
◦ Mitochondrial
hyperplasia
◦ 60% of cell volume

Basal cell is most common: 1.8% of benign
epithelial salivary gland neoplasms

6th decade

M:F = approximately 1:1

Most common in parotid

Trabecular
• Cells in elongated
trabecular pattern
• Vascular stroma

Tubular
◦ Multiple duct-like
structures
◦ Columnar cell lining
◦ Vascular stroma

Membranous
◦ Thick eosinophilic
hyaline membranes
surrounding nests
of tumor cells
◦ “jigsaw-puzzle”
appearance
Malignant –
1.Mucoepidermoid carcinoma
2. Adenoid cystic Carcinoma.
3. Adenocarcinoma.
4. Squamous cell carcinoma.
5. Malignant pleomorphic adenoma.
6. Acinic cell tumor
7. Malignant lymphoma
8. Anaplastic carcinoma




Painless asymptomatic mass (80%)
Pain=> perineural invasion (30%)
Facial nerve palsy or paresis (7-20%)
H/o prior parotid tumor indicates recurrence.




Trismus => advanced disease with extension
to masticatory muscles or less commonly
invasion into TM joint
Dysphagia => tumour of deep lobe of parotid
Ear pain=>extension into auditary canal
Numbness along Trigeminal nerve =>neural
invasion







Hard mass in parotid region
Skin ulceration/fixation
Fixation to adjacent structures
Examination of external auditary canal
for tumor extension
Regional lymph adenopathy
Blood or pus from stensen’s duct
Bulging of lateral pharyngeal wall or soft
palate






Most common salivary gland malignancy
5-9% of salivary neoplasms
Parotid 45-70% of cases
Palate 18%
3rd-8th decades, peak in 5th decade
F>M





Slow growing tumors
Limited local invasiveness
Low metastatic potential
High grade behave like SCC, low grade
behave like benign tumors
Sucessfully treated by adequate radical
excision

Presentation
◦ Low-grade: slow growing, painless mass
◦ High-grade: rapidly enlarging, +/- pain

Gross pathology
◦ Well-circumscribed
to partially
encapsulated to
unencapsulated
◦ Solid tumor with
cystic spaces


Areas of mucous secreting cells
Epidermoid and epithelial cells






Poorly encapsulated infiltrating tumors
Propensity to spread along nerves
Highly invasive but may remain quiescent for
a long time
Highest incidence of distant metastasis
Lung metastasis are most frequent.
Poor prognosis
 They
can arise within a preexisting benign
pleomorphic adenoma (CARCINOMA EX
PLEIOMORPHIC ADENOMA)
 They
may arise denovo (CARCINOSARCOMA)





Intermediate grade malignancy
Low malignant potential
May be bilateral or multicentric
Rarely metastasize
May spread along perineural planes





Most commonly in elderly females
Usually Non-Hodgkins
5-10% of patients with warthin’s
Enlarged parotid with a rubbery consistency
Enlarged regional lymph nodes




Squamous cell carcinoma
Sebaceous carcinoma
Salivary duct carcinoma
Malignant fibrohistiocytoma





Ultrasound
FNAC is the diagnostic
MRI is superior in demonstrating benign
tumors than CT
CT scan/MRI identifies regional lymph node
involvement/ extension into deep lobe /
parapharyngeal space
PET may be useful in assessing malignant
tumors





Efficacy is well established
Safe, well tolerated
Accuracy = 84-97%
Sensitivity = 54-95%
Specificity = 86=100%





First line of management
superficial lobe is involved, superficial
conservative parotidectomy
If deep lobe(dumb bell) also involved, total
parotidectomy with preservation of facial
nerve.
Enucleation should be avoided as recurrence
rate is high
Extracapsular enucleation-warthin’s tumor
◦ RADICAL PAROTIDECTOMY
Removal of the entire gland,facial nerve and
regional lymph nodes
Resection of all involved structures
positive
malignancy nodes
high grade tumors
local invasion
recurrent tumors if no h/o previous neck
dissection
deep lobe tumors






Skin grafting
Cervicofacial flap
Trapezius flap
Pectoralis flap
Deltopectoral flap
Microvascular free flap



Great auricular nerve
Hypoglossal nerve
Sural nerve
 >4
cm in diameter
 High grade
 Local invasion
 Lymphatic/neural/vascular invasion
 Tumor in/extending to deep lobe
 Recurrent tumours following re-resection
 Positive margins







High grade
Neural involvement
Locally advanced disease
Advanced age
Associated pain
Regional lymph node metastasis
Distant metastasis


Inflammation: whole parotid swollen
Neoplasm:A part of the gland is swollen