novel lesion first described in 2014 9 cases have been reported so far recently included in the 2017 who classification of odontogenic tumors

2. SUBMITTED BY: Lekshmy Jayan
I MDS
Department of Oral Pathology
GUIDED BY: Dr. Jayant

3. ODONTOGENIC TUMOR
 Group of neoplasm and tumor- like
malformations arising from cells of
odontogenic apparatus and their remnants.
 In simple terms, odontogenic tumors arise
from odontogenic or tooth forming apparatus.

4. Origin of Odontogenic
Tumors
Ectodermal
Dental
lamina( Cell
rests of
Serre)
Enamel
organ
REE
HERS( Cell
rests of
Malassez)
Mesenchymal
Dental
papilla
Dental sac

5. • Malignant Odontogenic Tumors
 Ameloblastic carcinoma
 Primary intraosseous carcinoma
 Clear cell odontogenic carcinoma
 Sclerosing odontogenic carcinoma
 Ghost cell odontogenic carcinoma
 Odontogenic carcinosarcoma
 Odontogenic sarcoma
 Benign Odontogenic Tumors
 Ameloblastoma
 Squamous odontogenic tumor
 Calcifying epithelial odontogenic tumor
 Adenamatoid odontogenic tumor
 Ameloblastic fibroma
 Primordial odontogenic tumor
 Dentinogenic ghost cell tumor
 Odontoma
 Odontogenic fibroma
 Odontogenic myoma
 Cementoblastoma
 Cemento-ossifying fibroma
Odontogenic
carcinoma with
dentinoid

6.  Odontogenic Cysts
Dentigerous cyst
Odontogenic keratocyst
 Lateral periodontal and botryoid odontogenic cyst
Gingival cyst
 Glandular odontogenic cyst
Calcifying odontogenic cyst
Nasopalatine cyst
Orthokeratinized odontogenic cyst
(Wright et al : Update from the 4th Edition of the World Health Organization Classification
of Head and Neck Tumours: Odontogenic and Maxillofacial Bone Tumors, 2017)

7.  First described by Mosqueda et al, 2014
 Found 6 cases of tumors that did not fulfil
the criteria of any described odontogenic
tumor
 Primordial odontogenic tumor is an intraoral
mixed odontogenic tumor consisting of dental
papilla like tissue covered with cuboidal to
columnar epithelium that resembles inner
enamel epithelium of enamel organ
(Mikami et al : Primordial odontogenic tumor: A
case report with histopathological analysis. 2017)

8. Soft tissue odontoma with massively enlarged dental
papilla
Soft tissue odontoma with monstrous papillomegaly
(Slater et al: Primordial Odontogenic Tumor: Report of a Case:2015)

9.  Still not clear
 But may possibly originated from
mesenchyme of an abortive tooth germ that
failed to produce a dental organ
 The mesenchymal tissue may have
stimulated the epithelium to proliferate
around it
 Mimics early/ primordial stages of tooth
development
(Ronell Bologna- Molina et al: Primordial odontogenic
tumor: an immunohistochemical profile: 2017)

10.  Novel lesion
 Only 9 cases reported so far
 Age= 3-19years
 Sex =
 Mandible : Maxilla = 6:1
 Posterior molar region
 All cases except one has been
reported in left side

11.  Asymptomatic expansile lesion
 Average size= 56mm (25-90 mm)
 Seen in association with unerupted teeth
 Aggressive lesion
( Toshinori Ando et al: A case report of priomordial
odontogenic tumor: A new entity in WHO
classification 2017: 2017)

14. Age/
Gender
Location Clinical findings Radiographic findings Treatment Follow
up
1.
18yr/M
Left posterior mandible from
the first molar to the angle of
the mandible
Asymptomatic buccal
swelling clinically
evident for 6 months
RL, UL, well defined,
45 9 40 mm, enclosing
the crown of the third
molar
Enucleation together
with embedded third
molar
20
years,
NED
2.16yr/M Left posterior mandible from
the first molar to the angle of
the mandible
Asymptomatic, buccal
and inferior mandibular
cortical bone expansion.
Clinically evident for 4
months
RL, UL, well defined,
55 9 50 mm, enclosing
the crown of the third
molar
Enucleation together
with embedded third
molar
LFU
3.
16yr/M
Left posterior mandible from
the first molar to the angle of
the mandible
Asymptomatic buccal
swelling. Clinically
evident for 1 year
RL, UL, well defined,
65 9 50 mm, enclosing
the crown of the third
molar
Enucleation together
with embedded third
molar
10
years,
NED
4. 3yr/F Left posterior mandible from
the first molar to the angle of
the mandible
Asymptomatic buccal
and lingual bony
expansion. Clinically
evident for 22 months
RL, biloculated, well
defined, 90 9 70 mm,
enclosing the crowns of
the second deciduous
and first permanent
molars. Root resorption
of the first deciduous
Enucleation together
with first and second
deciduous molars
and tooth 19
9 years,
NED

15. Age/
Gender
Location Clinical features Radiographic features Treatment Follow
up
5. 13yr/F Left posterior mandible
from the second premolar
to the upper third of the
ascending ramus
Asymptomatic
buccal swelling.
Clinically evident
for 4 months
RL, biloculated, well defined,
80 9 50 mm, enclosing the
third molar
Enucleation with the
third molar and
extraction of the first
and second molars
3 years,
NED
6.
3yr/F
Left posterior maxilla from
the first deciduous molar
up to the floor of the
maxillary sinus and
tuberosity
Asymptomatic
buccal and palatal
bony swelling.
Clinically evident
for 3 months
RL, UL, well defined, 35 9 30
mm, displacing the second
deciduous and first permanent
molars
Enucleation together
with the second
deciduous and first
permanent molars
6
months,
NED
7.
8yr/F Left posterior maxilla from
second premolar upto the
floor of the maxillary sinus
and tuberosity
Asymptomatic left
maxillary buccal
and palatal
swelling
well-defined RL associated
with an unerupted first
deciduous molar, which
induced buccal cortical plate
expansion and elevation of the
floor of left maxillary sinus,
and also slightly displaced the
first premolar toward palatal
side
Enucleation together
with the deciduous
first molar
16
months,
NED
8. 5yr/M Right posterior mandible
from deciduous first molar
to permanent first molar
Asymptomatic
buccal swelling
Well-defined homogenous
radiolucency pushing the
unerupted tooth to the base of
the mandible.
Enucleation together
with second deciduous
molar
7
months,
NED

16.  White, solid spherical mass
 Glossy and multilobulated
 If enucleated along with the
involved tooth then it is also
seen

18.  Loose and myxoid fibrous
tissue
 Scattered stellate and fusiform
fibroblast- forms central area
of tumor

19.  Cell-rich
ectomesenchymatous
tissue or myxoid tissue

20.  Periphery of lesion is covered by
columnar or cuboidal epithelium
 Resemble INNER ENAMEL
EPITHELIUM of developing
tooth
 No odontoblastic differentiation

21.  REE overlying enamel surface of
embedded teeth- no direct continuity
 Independent ectomesenchymal
proliferation??
 Induce proliferation of adjacent dental
lamina to surround it !!
(Mosqueda- Taylor et al ; Primordial odontogenic
tumor: Clinicopathological analysis of 6 cases of
previously undescribed entity: 2014)

22.  CK 14- positive in all epithelial layers

23.  CK 19 positive in columnar epithelium

24.  Vimentin strongly positive in mesenchymal tumor cells
Moderately positive in all epithelial layers
 Amelogenin -positive in cuboidal and columnar epithelium

25.  MOC-31- found in localised areas in epithelium
 SYNDECAN-1( CD138)- vary from entirely negative zones to focally
positive areas in epithelium
Strong stromal expression

26.  PITX2- Weak immunostaining in mesenchymal cells
Weak to moderate positivity in endothelial cells
Focal moderate positivity in epithelium

27.  CD34- strong positivity in mesenchymal tumor cells in contact or closer
to epithelial layers and blood vessels
Indicate presence of embryonic fibroblast
(Ronell Bologna et al: Primordial odontogenic tumor: A immuohistochemical profile, 2017)

28. Dentigerous
cyst
Ameloblastic
fibroma
Cemento-ossifying
fibroma
Odontogenic myxoma
Hyperplastic dental follicle

33.  Loose collagenous fibrous connective tissue with myxoid areas
 Small odontogenic epithelial nests
 Lined on inner surface by epithelium derived from Enamel Organ
 Epithelium never covers external surface
 Doesn’t show expansile growth as big as lesions reported with POT

34.  Highly cellular mesenchymal tissue
 Surface has single layer of odontoblasts adjacent to enamel organ
 Represent primordial ectomesenchymal odontogenic proliferation with
features closely resembling dental papilla
 (Mosqueda- Taylor et al ; Primordial odontogenic tumor: Clinicopathological analysis of 6
cases of previously undescribed entity: 2014)
Only
difference

35.  Enucleation of lesion by separating it from the
adjacent bone along with the impacted tooth
 No recurrence has been reported so far

38.  Primordial odontogenic tumor (POT) was first reported by Mosqueda-
Taylor et al in 2014.
 Classified into benign mixed epithelial and mesenchymal odontogenic
tumour in the 4th edition of the World Health Organization (WHO)
classification of Head and Neck tumours in 2017.
 Radiographic appearance and histopathological features
 However, there are only eight reported cases so far, therefore,
pathogenesis and the biological properties of this tumor are not well
understood.
 Reported case of 5 year old patient with POT

39.  5-year-old Japanese boy
 Chief complaint of delayed eruption of the second deciduous molar in
the right mandible
 No relevant medical or family history
 Intraoral examination revealed mobility of the adjacent first deciduous
molar, and buccal swelling in the affected area of the mandible with no
pain
 Normal overlying mucosa

41.  Surgical excision of the lesion was performed under general anesthesia
 The tumor was detached from adjacent bone, and surgically enucleated
in one piece

46.  Vimentin
 CK 18
 Mitotic activity of tooth germ
 CD 34
 All these support that the mesenchymal
component of POT is derived from
dental papilla of primordial tooth germ
 10-20th week- cap to late bell stage

47. FOR CASE REPORT

48. TOPIC ITEM CHECKLIST ITEM DESCRIPTION REPORTED
ON PAGE
TITLE 1 The area of focus and “case report” should appear in the title 
KEYWORDS 2 Two to five key words that identify topics in this case report 
ABSTRACT 3a Introduction – What is unique and why is it important? 
(UNSTRUCTURED) 3b The patient’s main concerns and important clinical findings 
3c The main diagnoses, interventions, and outcomes 
3d Conclusion—What are one or more “take-away” lessons? 
INTRODUCTION 4 Briefly summarize why this case is unique with medical literature
references.

PATIENT INFORMATION 5a Demographic information 
5b Main concerns and symptoms 
5c Medical, family, and psychosocial history including genetic information 
5d Relevant past interventions and their outcomes 
CLINICAL FINDINGS 6 Relevant physical examination (PE) and other clinical findings 

49. TIMELINE 7 Relevant data from this episode of care organized as a timeline (figure or table) X
DIAGNOSTIC
ASSESSMENT
8a Diagnostic methods (PE, laboratory testing, imaging, surveys) 
8b Diagnostic challenges 
8c Diagnostic reasoning including differential diagnosis 
8d Prognostic characteristics when applicable
THERAPEUTIC
INTERVENTION
9a Types of intervention (pharmacologic, surgical, preventive) 
FOLLOW UPS AND
OUTCOMES
10a Clinician and patient-assessed outcomes when appropriate -
10b Important follow-up diagnostic and other test results X
DISCUSSION 11a Strengths and limitations in the approach to this case X
11b Discussion of the relevant medical literature 