seminar of odontogenic tumors

4. Contents
Definations
Classification
BENIGN TUMORS OF ODONTOGENIC
EPITHELIUM WITHOUT ECTOMESENCHYME
AMELOBLASTOMA
CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
ADENOMATOID ODONTOGENIC
TUMOR
SQUAMOUS ODONTOGENIC
TUMOR

11. AMELOBLASTOMA
(Admantinoma,Admantoblastoma,Multilocular cyst)

12. CHURCHIL
(1934)
ADMANTINOMA AMELOBLASTOMA
MALASSEZ
(1985)
*Formation of hard tissue

14. Incidence: 1 % among all oral tumors
2nd most common odontogenic tumor
Age: Average age of diagnosis is range of 33-39 yrs
Sex: Males are more affected than femels
Site: 80% of all cases mandible is most commonly affected

15. Molar angle >>> Pre-molar & anterior region
Ramus area 3 times regions comined
more commonly

17. Slow growing painless ovoid or fusiform bony
hard swelling of the jaw
Lesion causes expansion thinning&distortion of
the cortical plates of the jaw bones &
displacement of regional teeth causing
GROSS FACIAL ASYMMETRY
Patient report with typical long time history of
presence of an abcess or cyst that was
operated previously but has recurred
Expansion of the bony cortex occurs since
slow growth rate of the tumors allows time for
the periosteum to devlop thin shell of bone
cracks under digital pressure & phenomenon is
so called “EGG SHELL CRACKING”

18. Higher cancellous bone percentage in the maxilla
facilitates the spread of ameloblastoma whereas
the density of cortical plates in the mandible tend
to limit spread of neoplasm

19. Follicular Ameloblastoma
Plexiform Ameloblastoma
Acanthomatous Ameloblastoma
Granular cell Ameloblastoma
Basal cell type of ameloblastoma
Desmoplastic Ameloblastoma

20. Most commoly encountered variant with highest rate
of recurrence 29.5%
In this variant, tumor cells are arranged in the form
of few follicles distributed in connective tissue

21. Follicles have peripheral layer of
ameloblast like cells i.e. Coloumnar cells
have nucleus arranged away from the
base of the cells
Central mass of polyhedral loosely
arranged cells resembling the STELLATE
RETICULUM.
The stellate reticulum like tissue has
undergone complete breakdown or cystic
degeneration & in such case there is
flattening of peripheral coloumnar cells
Cyst formation is relatively common seen
in this type of ameloblastoma

22. The ameloblast like tumor
cells are arranged in irregular
masses or more frequently as
a network of inter-connecting
strands of cells
These strands are bounded by
ameloblast like cells on either
side having back to back
arrangement with stellate
reticulum like cells in
between.

23. Stellatereticulumcellsarelessprominentthaninfollicularpattern
Connectivetissuestromaisseenenclosedbetweenthenetwork
ofodontogenicepithelialcells
Areasofcysticdegenerationofstromaarealsocommon

24. This variant shows lowest
reccurence of about 4.5%
Tumor cells are arranged in the
form of follicles with peripheral
ameloblast like cells & central
stellate reticulum like cells
The cells occupying the position
of stellate reticulum undergo
squamous
metaplasia,sometimes with
keratin formtion in the central
portion of the tumor islands

25. This variant shows marked transformation of cytoplasm usually
of the stellate reticulum like cells & it takes on very
coarse,granular,eosinophilic appearance
Ultrastructural studies shows,these cytoplasmic granules
presents lysosomal aggregate
This type appears to be aggressivelesion with marked tendency
for recurrence unless appropriate surgical measures are
instituted for 1st operation

27. It bears considerable resemblance to the basal cell carcinomaof
the skin
It is rarest histological type
Epithelial tumor cells are more premitive & less coloumnar are
generally arranged in sheets ,more so than in other tumor types

28. Characteristically it is found in dense collagen stroma that may
appear hyalinized & hypo cellular
It has greater tendency to grow in thin strands & cords of
epithelium rather than in an islands like pattern
Central cells are often scanty in epithelial proliferation & the cells
making up the periphery of the strands & cords often are
flattened or cuboidal rather than tall columnar in appearance
Reverse polarity of nuclei and sub-nuclear vacuole formation may
be difficult to recognize
Occasional classical islands of follicular ameloblastoma among
the predominant strands & cords seen
Without these classical islands, Diagnosis is difficulut

29. Histologically resembles typical central or intra- osseous
ameloblastoma but which occur in the soft tissue outside and
overlying the alveolar bone
Approx. 2:1 ratio of occurrence in mandible over maxilla

30. Admantinoma of long bones
Occurs in TIBIA (90%)
Cases also seen with Ulna,Femur &Fibula
PITUTARY AMELOBLASTOMA (craniopharyngioma,Rathke’s
pouch tumor)
Neoplasm involving central nervous system which grow as
pesudoencapsulated mass, usually in the suprasellar area but
occasionally in intrasellar area & often destroy pitutary gland
It is thought to originate from the unobliterated portions of
foetal craniopharyngeal duct
Similarity is noted between COC and this lesion because of
histological resemblance of islands & nests of ghost cells as well
as calcification & cyst formation is common

31. 2nd & far less frequent growth pattern seen in
the intra osseous ameloblastoma
This growth pattern is seen in approx. 6 % of
ameloblastoma
High percentage of these lesions are
associated with an impacted tooth mostly
cited provisional diagnosis is dentigerous cyst
Better overall prognosis & much reduced
incidence of recurrance

32. Lining epithelium exhibiting alterations
virtually identical with those described by
*VICKERS &GORLIN as representing with
early ameloblastomatous changes in the
dentigerous cyst
Nodules of tumorprojecting intraluminally
Ameloblastomatous lining epithelium
proliferating into the connective tissue wall
Islands of ameloblastoma occuring isolated
in the connective tissue wall

34. Luminal parakeratin layer may or may not be
present
Ameloblastic epithelium may be proliferative with
extension of the ameloblastic epithelium into the
lumen of cystic cavity.This feature is termed as
intra luminal proliferation
Growth pattern resembles to plexiform type of
ameloblastoma
Thus, lesion also been referred to as plexiform
unicystic ameloblastoma

35. Multilocular cyst like lesion of the jaw
Tumor exhibited a compartmented appearance
with septa of bone extending into Radioluncent tumor mass.
The lesion is unilocular in some cases periphery
is smooth,or may be scalloped & irregular
In advanced lesions producing jaw expansion
thinning of cortical plate may be seen

36. Odontogenic Kertocyst
Dentigerous cyst
Central giant cell granuloma
Central hemangioma
Aneurysmal bone cyst
Pindborg’s tumor
Fibromyxoma

38. Complete removal of the neoplasm
regardless of how it is accomplished will
result in a cure of the patient
Radical & Conservative surgical
excisio,curettage,chemical &
electrocautery,radiation therapy or
combination of surgery & radiation
Curettage is least desirable as it has
highest incidence of recurrance
This neoplasm is generally highly
radioresistant
Long term follow up of the pt. is an
absolute necessity

39. 1st described in 1956 by Dr. Jens J pindborg
It is an uncommon benign odontogenic neoplasm that
is epithelial origin
Tumor are reminiscent of the cells in stratum
intermedium layer of the enamel organ in tooth
devlopment
Remnants of the premitive dental lamina found in the
initial stage of odontogenesis and these epithelial rests
are more likely true progenitor cells
Definite etiology of this neoplasm is still enigmatic

40. Incidence rate :- 1 % of all
odontogenic tumor
Age :-Commonly occurs in middle
aged adults (Mean age is 40 yrs)
Sex :- Both sexes are almost equally
affected
Site :-Mandible involved more than
the maxilla
Molar region is three times
than that of
bicuspid region

41. Tumor usually present as slow growing painless
swelling of the jaw with expansion & distortion of the
cortical plates
Swelling is usually bony hard and clinically it can be
either well defined or diffused in nature
Displacement of regional teeth, with derangement of
occlusion & facial asymmetry
Pain,paresthesia & related symptoms may devlop on
rare occasion

42. Lesion appear as diffused or
well-circumscribed unilocular
radiolucent area
Many small irregular bony
trbeculae tranversing the
radiolucent area in many
directions producing multi-
locular or honey-comb
pattern

43. Scattered flecks of
calcification throughout
the radiolucency have
given rise to the
descriptive term ”Driven
snow appearance”
Lesion is totally
radiolucent & is asso.
With an impacted tooth
thus leading to mistaken
clinical diagnosis of
dentigerous cyst

44. CEOT IS composed of sheets or islands of polyhedral
odontogenic epithelial cells in bland fibrous connective tissue
stroma
Occasionally the cells are arranged in cords or rows
mimicking adenocarcinoma
Tumor cells have Well outlined cell borders with finely
granular eosinophilic cytoplasm & intercellular bridges are
promient
Nuclei are frequently pleomorphic with giant nuclei &
multinucleation being quite common but mitotic figures are
rare
Another characteristic feat. of this neoplasm is calcification
seen that may be in the form of concentric rings called as
“LIESEGANG CALCIFICATION”

47. Calcifying epithelial
odontogenic cyst
Adenomatoid odontogenic
tumor
Poorly differentiated carcinoma
Ameloblastoma
Ameloblastic fibro-odontome
Dentigerous cyst
Central ossifying or
cementifying fibroma

48. Variety of alternative surgical treatment
methods used to successfully manage pindbor
tumor
Small intra bony lesions with well defined
borders can be treated with Enucleation or
curettage followed by judicious removal of thin
layer of bone adjacent to the tumor
Maxillary tumor should be treated more
aggressively than a similar sizelesion in the
mandible

49. Recurrent or persistent tumors ,which over an extended
time have become larger and more extesive (greater than 4
cm) would require segmental resection such as partial or
Hemi-mandibulectomy or Hemi-maxillectomy
Radical resection of the affected jaw portion
and any asso. Soft tissues not less than 1 cm in
every direction
Adjunctive external beam radition therapy is
spread to cervical lymph nodes & adjunctive
chemotherapy may play some role in control of
distant organ metastasis in some patiet

50. Adenomatoid odontogenic tumor is generally
considered as uncommon tumor occurs mostly
in association with an unerupted maxillary
cuspid
Some considered it as benign neoplasm while
other categorized it as hamartomatous
malformation due to the limited size and to the
lack of recurrence in most of cases

51. Specific stimulus that triggers proliferation of the
progenitor cells of adenomatoid tumor is unknown
AOT is of odontogenic origin bcz
Its exclusive occurrence within
the tooth bearing areas of the jaws
(Most often asso. closely With
unerupted or impacted tooth )
Its cytoplasmic resemblance to
dental lamina &components of
enamel organ

52. Age : Tumor usually occurs in
(2nd -3rd)decade of life.Rarely it
occurs in older age
Sex: Females are more
commonly affected in
comparison to males
Site :Lesions most typically
occurs in the maxillary anterior
region
74% cases tumors were
associated with an unerupted
tooth,& in over 2/3rd of the
cases tooth was maxillary or
mandibular cuspid

53. Tumor usually present as
slow enlarging,small,bony
hard swelling in max. ant.
Region
Lesion measured between
1.5-3 cm, although large
lesion,exceeding 7 cm have
been reported

54. The lesion often causes elevation of upper
lip,displacement of regional teeth & expansion
of cortical plates
AOT may occur within the jaw bones or the
gingiva peripheral lesions present as painless
gingival colored maas, that ranges from 1-1.5
cm in diameter
It is 10 times more prevalent in maxillary gingiva
than mandibular gingiva
(F:M ratio for gingival lesion 14:1)

56. AOT presents well circumscribed unilocular radiolucentarea
which often encloses a tooth or tooth like structure (mostly max.
canine)
About 65% cases reported demonstrate multiple small radio-
opaque foci of varying radio density may be present inside the
lesion and finding is knownas“snowflake calcification”
Most lesions are pericoronal or juxta coronal but the radiolucency
may extend apicaly beyond the CEJ on atleast one side of the root
Divergence of root & displacement of teeth occurs more
frequently than root resorption
Gingival lesions may cause slight erosion of the underlying
alveolar bone cortex

57. Macroscopic feature :-
central AOT’s appears soft, roughly spherical mass with
a distinct fibrous capsule
On gross sectioning, Tumor may exhibit white to tan
,solid to crumbly tissue or one or more cystic spaces of
varying sizes with yellowish brown fluid or semisolid
materials fine hard gritty granular material & one to
several larger calcified masses
Crown of an embedded tooth in solid tumor mass o
projecting into cystic cavity

59. Microscopic features
Tumor is made up of multinodular proliferation of
spindle,cuboidal & coloumnar cells in a variety of patterns
comprising of scattered duct like structure,eosinophilic
material & calcification in several forms
These ameloblast like cells or epithelial cells are arranged in
different pattern like islands sheets,stransds, whorled
mass,rosettes,duct like pattern or convulkated pattern
varying no. of duct like structure with lumina of varying size
that are lined by a single layer of cuboidal or coloumnar
epithelial cells that have nuclei that frequently are polarized
away from the lumen
These duct like or microcyst lumina frequently are lined by an
eosinophilic rim of varying thickness(Hyaline ring)

60. Stellate reticulum like spindle cells & occasionally round or
polygonal epithelial cells dominate the tissue between cell rich
nodules
Small amount of eosinophilic material or calcifications also may
be present between these cells
Anastomosing strands of basaloid epithelial cells which
resembles cell rests of dental lamina are arranged in plexiform,
trabecular,cribriform,or lattice like configuration
AOT’s contain a few clusters of well defined calcifying epithelial
odontogenic tumor like foci with eosinophilic polyhedral
squamous epithelial cells & prominent intercellular bridges
&occasionally mild nuclear pleomorphism seen

61. Dentigerous cyst
Globulomaxillary cyst
Lateral periodontal cyst
Odontome
Unicystic ameloblastoma
Ossifying or Cementifying
fibroma
Calcifying epithelial
odontogenic tumor
Calcifying epithelial
odontogenic cyst

62. By conservative surgical exicision and
recurrence if it ever occurs is exceedingly rare

63. SQUAMOUS ODONTOGENIC TUMOR
(BENIGN EPITHELIAL OONTOGENIC TUMOR)
Squamous odontogenic tumor are rare,sometimes
multifocal potentially aggressive neoplasm derived
from odontogenic epithelium
1st repoted in 1975
This lesion is mistaken histologic identification as an
acanthomatous ameloblastoma or as well
differentiated epidermoid carcinoma

64. Origin/Histogenesis
Rests of malassez source of epithelial
proliferation for lesion
asso. With alveolar processes
adjacent to the lateral
root surface of the teeth
Remanants of Lesion that
dental lamina- devloped in asso. With
crowns of unerupted or
impacted teeth
Surface stratified source of extraosseous variant
Squamous epithelium
&
Rests of serres

65. Age :-Occurs commonly among young adults between (19-31 yrs) of
age
Sex:-slight male preponderance but some authors says female
predilection
Site :-Mandible is most commonly affected
Maxilla Bicuspid molar area
Mandible centered around incisor to
cuspid area
Multiple site involvement including both maxillary and
mandibular involvement in the same patient

66. Initially there can be painless swelling on the
gingival areas of the jaw with mobility and
looseness of the regional teeth
There can be local tenderness in the area upon
palpation
Many lesions are asymptomatic and are
discovered incidentally during radiographic
examination

67. Radiographically,SOT
present as well-
circumscribed often
semilunar or triangular
shaped,unilocular
radiolucent area with
sclerotic border
Lesions of SOT mimmic
chronic periodontitis due
to similar type of extensive
bone loss

68. SOT composed of entirely of islands of
mature squamous epithelium without
peripheral palisaded or polarized
coloumnar layer
This peripheral layer is usually quite
flattened or at least cuboidal
The squamous cells are very uniform &
exhibit no pleomorphism,nuclear
hyperchromatism or mitotic activity
Occasionally,individual cell keratinization is
present but no epithelial perals moreover
focal areas of keratin or parakeratin is seen
Remaining epithelial cells of islands
composed of mature intermediate cells
with prominent desmosomal
bridges.Intercellular bridges usually seen
with no difficulty

69. Fibrous stroma of the
tumor is simply mature
bundles of collagen fibre
and is devoid of any
peri-insular inductive
effect
Cells in the islands lacks
variation in cell size
shape & nuclear staining
Mitotic figures are
characteristically seen in
squamous cell
carcinoma

70. 3 OTHER VARIABLE FINDINGS
Microcyst formation involving
only small portions of epithelial
Islands
Laminar calcification in the epithelium
Globular , hyaline eosinophilic structure
within the islands which
are not amyloid

71. Acanthomatous
ameloblastoma
Lateral periodontal cyst
Squamous cell carcinoma
Central ossifying or
Cementifying fibroma
Collateral type of OKC
Histiocytes-X

72. Enucleation,curretage, local excision are
modalities
Clinically aggressive lesion have been treted by
En-bloc ressection