Oral Pathology II Forth Year

1. Februray 29, 2009
Salivary Glands
Classification, General Considerations
&
Tumors Like Conditions
By Louay Jaber DDS, MSc, MSD, PhD

2. The Normal Salivary Gland
• The system is comprised of
major & minor salivary glands
– Major: Parotid, submandibular &
sublingual.
– Minor:
• They produce the fluid that
constitute oral saliva
– Parotid: serous
– Submandibular: serous & mucous
– Sublingual: mucous & serous
•
•
•
•
Palate: mucous
Tongue: mucous & serous
Lip: mucous
Buccal mucosa: mucous
Oral
mucosa
Acinus
Intercalaetd-Striated-Excretory
“ducts”

3. The Normal Salivary Gland (Cont.)
“Parotid gland”
Lymph node
Serous Acini
& striated duct
Facial nerve

4. The Normal Salivary Gland (Cont.)
“Submandibular, sublingual & minor glands”
Submandibular
Sublingual
Minor

5. Mucocele
70% in the lower lip
The remainders
floor of the mouth, tongue & buccal
mucosa
Third decades of life
Men > women (slight)
Small dome-shaped swelling
Size 0.2-1.0 cm
Mucoceles of the floor of the
mouth can be a large size
(several centimeters-Ranula)
Mucocele
Ranula

6. Mucocele
Pts might report a fluctuation
in size related to meals or
rupture
They are generally soft &
fluctuant (older becomes
firmer)
They are painless
They develop rapidly within
hours to days
Ruptured mucocele
Mucocele

7. Mucocele
Microscopically
Pool of mucus
It is a rounded pool of mucus
within fibrous connective tissue
Inflammatory reaction
(Macrophages that contain
phagocytized mucus)
Phagocytic macrophages

8. Mucus Retention Cyst
 Etiology:
It results from obstruction of salivary
flow because of sialolith, periductal
scar or impinging tumor
 Clinical features:
it is commonly found in the upper lip,
palate, cheek and floor of the mouth.
It represents asymptomatic swelling
Microscopically
 Retention cyst: Epithelial-lined
fibrous tissue wall surrounds the
mucus pool
 Little or no inflammatory reaction (no
epithelial rupture
Cuboidal epithelium

9. Ranula
 It is a clincial term that includes mucus extravasation
phenomenon and mucus retention cyst
 Occur specifically in the floor of t he mouth
 Etiology:
 Trauma & ductal obstruction
 Sialolith: represents precipitation of calcium salts
around the central nidus of cellular debris
 Clinical features:
 it is fluctuant, unilateral soft tissue mass in the floor of the mouth
 Histopathology:
 It is similar to mucus retention cyst

10. Necrotizing Sialometaplasia
Clinically
 It is a reactive inflammatory
condition of the salivary glands
 Average age is 46 years
 Male predominence 2:1
 Palatal location preference
 Deep crater-like ulcer, develops
rapidly & slow to heal
 Size 1-5 cm.
Unilateral ulcer of necrotizing sialometaplasia

11. Necrotizing Sialometaplasia
Pathogenesis: Ischemic
necrosis or infarction
 Traumatic injury
 Dental injection
 Denture use
 Adjacent tumor & cyst
 Surgery
 Upper respiratory
infection or allergy
Swelling but no ulceration of necrotizing sialometaplasia

12. Necrotizing Sialometaplasia
Acini necrosis
Histologically
The principle
characteristics are:
 Lobular coagulative
necrosis of acini
 Squamous metaplasia of
ducts
 Pseudoepitheliomatous
hyperplasia
 inflammation
Necrotizing sialometaplasia

13. Necrotizing Sialometaplasia
Necrotic mucous acini &
mild inflammatory infiltrate
Squamous metaplasia (ducts)

14. Infectious Conditions
 Mumps:
 It is an infectious , acute viral sialadenitis primarily
affected the parotid glands
 It is the most common salivary gland diseases
 Etiology:
 The causative agent is a paramyxovirus
 2-3 weeks incubation period
 Transmission by direct contact with salivary droplets

15. Mumps
 Clinical features:
 Fever
 Malaise
 Headache
 Chills
 Preauricular pain
 Parotid swelling
 Male = female
 Young adults & children

16. Mumps
 Complications:
 Serious complication in adults can occur:
 Oophoritis
 Orchitis
 Widspread involvement can include
 Liver
 Pancreas
 Kindney
 Nervous system

17. Mumps
 Differential diagnosis
 Bacterial infection (suppurative parotitis)
 Salivary calculi
 Lymphoma
 Lymphoepithelial lesion
 Metabolic diseases

18. Mumps
 Treatment & Prognosis
 Symptomatic therapy
 Bed rest
 Analgesics
 Corticosteroids (variable success)
 Vaccination is now available

19. Metabolic Conditions
Sialadenosis
 It is non-neoplastic & non-inflammatory salivary gland
enlargement
 It is related to metabotic factor or
secretory dysfunction
 Painless bilateral swellings
 Peak incidence: 5th & 6th decades of life
 Slight female predominence
 Swelling develops slowly, painless & accompanied by
decreasing salivary secretion

20. Metabolic Conditions
Sialadenosis
It is usually associated
with systemic
conditions:
 Diabetes mellitus
 Malnutrition
 Liver cirrhosis (Chronic
Alcoholism)
 Hyperlipidemia
 Acromegaly
Enlargement of parotid associated with
chronic alcoholism & liver cirrhosis

21. Metabolic Conditions
Sialadenosis
Microscopically
As the disease persistsAtrophy of the paranchymal
tissue but compensatory
increase in the amount of
adipose tissue
Inflammatory cell infiltrates
are absent
Atrophy of parotid parenchymal tissue &
increase of intraglandular fat

22. Sjögren Syndrome
 It is the expression of an autoimmune process that principally
results in
 Rheumatoid arthritis
 Dry eyes (keratoconjunctivitis sicca)
 Dry mouth (xerostomia)
 Lymphocytic replacement of lacrimal
and salivary glands

23. Sjögren Syndrome
 Clinical features:
 Peak age: 50 yo
 Parotid gland enlargment
 Treatment:
 Artificial saliva and tears & preventive oral measures

24. Sjögren Syndrome
Focal aggregates of lymphocytes, periductal lymphocytes & dilated ducts

25. Mixed Tumors
“Pleomorphic Adenoma”
 It is the most common benign neoplasm
of salivary glands origin
 It represents 45-74% of all salivary gland
tumors
 Slow growing & asymptomatic,
 Average age is about 43 yo.
 Recurrent lesion occurs as multiple
nodules & are less mobile than initial
lesion.

26. Mixed Tumors
“Pleomorphic Adenoma”
CT revealed a mixed tumor
medial to the mandibular
ramus
It has prominent cartilagenous
& osseous elements that led
initially to diagnosis of
osteochondroma

27. Mixed Tumors
“Pleomorphic Adenoma”
 The most common intraoral site is
the palate followed by the upper
lip & buccal mucosa
 Mobility is limited for palatal
tumors.
 Large intraoral tumors are
susceptible to trauma

28. Mixed Tumors
“Pleomorphic Adenoma”
Submandibular
Small glistening
capsular surface
 Gross finding: It is
irregular round to ovoid
mass & well defined
borders
Parotid
Homogeneous tan
or tan white surface

29. Mixed Tumors
“Pleomorphic Adenoma”
Gross findings
Translucent central zone
represents myxochondroid
tissue
The presence of multiple
individual nodules are typical
of recurrent mixed tumor

30. Mixed Tumors
“Pleomorphic Adenoma”
Microscopic findings
Composed of epithelial
& mesenchymal like
tissue
Present or absent of
fibrous capsule

31. Mixed Tumors
“Pleomorphic Adenoma”
Cystic
degeneration
Prominent osseous
differentiation in
mixed tumor
Epithelial cell in
mixed tumor
Cytokeratin
immunoteactivity
in epithelial cells

32. Mixed Tumors
“Pleomorphic Adenoma”
Microscopic findings
 In the absence of surgical
intervention, viable epithelial cells
within necrotic tissue suggest a
malignant transformation
 Rarely tumor cells are seen within
vascular spaces

33. Mixed Tumor
“Treatment”
 Parotidectomy & excision of the scar tissue with
preservation of the facial nerve are recommended
(specially recurrent)
 Long term follow up is recommended more than 5 years
 The risk of malignant degeneration increases with time
 Radiotherapy has been found by some investigators to be
useful in some recurrent mixed tumor

34. Carcinoma Ex-Mixed Tumor
“Clinical Features”
 It arises from a benign mixed tumor (diagnosis requires
identification of mixed tumor)
 20% of patients had previous operation for mixed tumor
 The risk for malignant transformation correlates with the
duration of mixed tumor
 Painless mass or sometimes associated with facial nerve
pain or palsy
 Tumor is freely movable or sometime fixed to underlying
tissue (especially with recurrent tumors)

35. Carcinoma Ex-Mixed Tumor
“Microscopic Findings”
Myxochondoid bening elements &
carcinomatous elements
Capsular
invasion

36. Carcinoma Ex-Mixed tumor
“Treatment”
38-53% develop recurrence
Distant metastasis to lung, bone, brain, liver &
subcutaneous tissue
Radiotherapy alone has proven ineffective, although
it may have a beneficial role when combined with
surgery

37. Basal Cell Adenoma
It is composed of cells
predominantly of one type
Basal cell adenoma:
Occurs mainly in parotid
Slow growing & painless
Can be multinodular
Age 35-80
Male predominence
Well circumscribed mass near
the inferior pole of the parotid

38. Basal Cell Adenoma
Solid
Trabecular
Solid

39. Basal Cell Adenoma
Immunostaining for cytokeratin
Histology:
Ultrastructure shows ductal cells

40. Basal Cell Adenoma
Basal cell adenoma usually
lack cribriform pattern
Histology:
Adenoid cystic carcinoma with
clear cytoplasm & angular nuclei

41. Basal Cell Adenoma
Treatment & prognosis:
Conservative surgical
excision including a margin
of normal uninvolved tissue
Prognosis is good and
recurrence rate is so low
Small cells in the periphery of the epithelial islands
And larger cells adjacent to the tumor islands

42. Malignant Epithelial Tumors
“Mucoepidermoid Carcinoma”
It is the most common
malignant salivary
glands tumor
It represents 15.5% of all
benign & malignant
tumors at all sites
resemble a mucoceles.
Size varies from 1-12cm

43. Mucoepidermoid Carcinoma
It is believed to arise from
salivary duct system
Normal duct-lining epithelium
Neoplastic transformation

44. Mucoepidermoid Carcinoma
 Ionizing radiation increases the risk for its developing
 Occurrence:
 45% Parotid gland
 7% Submandibular gland
 1% Sublingual gland
 21% in the palate and 19% for the rest of the minor
salivary glands.
 Mean age is about 47 years with the age range between
8 to 92 yo.
 Women > men

45. Mucoepidermoid Carcinoma
 Typically, it is a solitary painless mass
 2/3 of pts. are asymptomatic
 if growing rapidly, usually accompanied with pain &
mucosal ulceration, and sometimes a discharge of fluid
resemble abscess.
 6 years average between onset & diagnosis (high grade
lesions demonstrate a 1.5-year interval before diagnosis).

46. Mucoepidermoid Carcinoma
According to cytologic features, it is divided into:
- Low
- Intermediate
- High grade types.
 All grades of this neoplasm are carcinomas and
have the potential to metastasize.
 They are epithelial mucin-producing tumor

47. Mucoepidermoid Carcinoma (Central)
This lesion may also arise centrally within the mandible

(Differential diagnosis: giant cell granuloma & odontogenic tumors).
Asymptomatic radiolucencies
Mandibule > maxilla
Third molar region is the
most likely to be involved

48. Mucoepidermoid Carcinoma (Central)
It
arises from either:
Ectopic salivary gland tissue
Neoplastic transformation of epithelial lining of odontogenic cysts
Glandular odontogenic cyst
Mayer’s mucicarmine stain
highlights numerous mucus
cells in a dentigerous cyst

49. Mucoepidermoid Carcinoma
Treatment & Prognosis:
 low grade usually follow a benign course.
However, in several instances low grade lesions
have metastasize widely.
 High grade metastasize widely (60% of cases).
 Surgical, or surgery plus postoperative
radiotherapy (high grade)
 Central mucoepidermoid carcinoma is usually of
low grade (40% recurrence rate).

50. Adenoid Cystic Carcinoma
Oral mucosa overlying this palatal mucosa is ulcerated
Clinical Features
• 50-70% starts in the
minor salivary glands.
• If major salivary gland
(parotid is the most affected)
• Age: 5th and 7th decades
This tumor appears
deceptively well circumscribed

51. Adenoid Cystic Carcinoma
 No gender predilection
 (slight female predominance).
 Unilocular mass
 Firm on palpation
 Occasional pain or tenderness
 Slow growth rate
 Bone invasion occurs
 Lung metastasis
Sublingual gland tumor.

52. Adenoid Cystic Carcinoma
Treatment & prognosis:
 Surgery is the treatment of choice
 Radical resection is justified to obtain surgical
margins that are free of tumor
 Multiple-agent chemotherapy showed some
promise for postoperative treatment
 High recurrence rate

53. Acinic Cell Carcinoma
Clinical features
 Age: 5th
 No
to 6th decades of life
gender predilection
 It
represents 14% of parotid
gland tumor
 9%
of total salivary gland
carcinoma of all sites
 50%
of cases, the clinical
appearance is a benign lesion

54. Acinic Cell Carcinoma
Usually less than 3 cm in
diameter
Pain
The interval between the
initial appearance &
treatment is 6 months to 5
years
The
origin is the ductal cells

55. Acinic Cell Carcinoma
Treatment & prognosis:
 Surgery is the preferred treatment
 Seldom metastasize
 Tendency to recur

56. Polymorphous Low-Grade Adenocarcinoma
• It is considered to be low grade malignancy and low risk
of metastasis
• Age: 5th to 8th decades
• No gender predilection
• Occurs in minor salivary
glands (palate)
• Firm, non-ulcerated &
non tender
• Size between 1-4 cm
• Slow growth
Well circumscribed mass at the junction of the hard &
soft palate

57. Polymorphous Low-Grade Adenocarcinoma
Partially circumscribed but lack encapsulation

58. Polymorphous Low-Grade Adenocarcinoma
Treatment & prognosis:
 Conservative surgical excision
 Prognosis is good

59. Carcinoma Ex-Mixed Tumor
“Microscopic Findings”
The carcinomatous elements appeared
separated from benign element
Apparent malignant transformation

60. Carcinomatous & benign Components of ExMixed
• w

61. Mucoepidermoid Carcinoma
Fluctuant because of cyst formation
Mucin filled cystic spaces

62. Mucoepidermoid Carcinoma
Microscopic features:
 The name is a contraction of
 epidermoid and mucus-secreting carcinoma
A close association of mucous
& epidermoid cells
Mayer’s mucicarmine
hightlights the extracellular &
Intracytoplasmic mucin

63. Mucoepidermoid Carcinoma
Mucoepidermoid carcinoma incites
secondary lymphoid proliferation
The lymphoid response extends
along the periphery of the tumor

64. Mucoepidermoid Carcinoma
Low grade. Note
Intracystic spaces
Intermediate grade.
hyperchromatic nuclei
& several microcystic spaces
High grade
Focal necrosis

65. Epidermoid &
mucus cells
Epidermoid cells
solid & infiltrative
Central Mucoepidermoid
Carcinoma
Cyst
Solid & cystic
neoplastic area
Characteristic variety
of cell types

66. Adenoid Cystic Carcinoma
Tubular pattern in the top
& bottom. A cribriform pattern
in the center
Epithelial cells have a clear
Cytoplasm, poorly defined
border & irregular shaped nuclei
Immunoreactivity of the
tumor cells for cytokeratin

67. Adenoid Cystic Carcinoma
Mitotic figures
The tumor appears
well circumscribed
Myoepithelial &
ductal cells

68. Adenoid Cystic Carcinoma
Neural invasion
Comedo-type necrosis

69. Acinic Cell Carcinoma
Well differentiated acinar cell
» Cytoplasmic granules.
» Slightly basophilic cytoplasm
» Eccentricaly located nuclei
Acinar cells

70. Acinic Cell Carcinoma
Papillary cystic growth pattern
Follicular pattern

71. Acinic Cell Carcinoma
Cluster of neoplastic epithelial cells & numerous
electron dense cytoplasmic granules

72. Polymorphous Low-Grade Adenocarcinoma
The nuclei are round or ovoid
& have a slightly irregular contour
Tumor cells are often
concentrically arranged