Odontogenic Cysts Dr. T Flashcards
What are the two types of Odontogenic Cysts?
Inflammatory
or
Developmental
List the type of Inflammatory cysts
(4)
- Periapical (radicular)
- Residual periapical
- Buccal bifurcation
- Paradental
List the types of Developmental Cysts?
(9)
‐ Dentigerous
‐ Eruption
‐ Gingival cyst of newborn
‐ Gingival cyst of adult
‐ Lateral periodontal
‐ Glandular odontogenic
‐ Odontogenic keratocyst
‐ Orthokeratinized odontogenic
‐ Calcifying Odontogenic
All of the following are histologically the same because they are all what?
-Periapical (radicular)
‐ Residual periapical
‐ Buccal bifurcation
‐ Paradental
‐ Dentigerous
‐ Eruption
‐ Gingival cyst of newborn
‐ Gingival cyst of adult
squamous epithelial lined cysts
What are the sources of epithelium
within the jaw bone ?
(6 sources)
▪ Epithelial rests of Malessez
▪ Reduced enamel epithelium
▪ Fissural cysts – when 2 pieces of bone come together
▪ Odontogenic cysts
▪ Epithelial component of odontogenic tumors
▪ Salivary gland inclusions – rare, incorporated in development
radicular cyst, inflammatory cyst are other names for
Periapical Cysts
▪ The most common cyst of the jaws
Periapical Cysts
Periapical Cysts
Demographic and location
▪ Any age (peak in 3rd ‐ 6th decades, rare in 1st decade)
▪ No sex predilection
▪ MX > MD (anterior MX most common)
Tooth vitality and Periapical Cysts
- Involved tooth usually non‐vital/non‐responsive with thermal and electric pulp testing
- Should test vitality of tooth if see radiolucency in apex\
- If tooth vital, and still see radiolucency ► should do biopsy
Periapical Cyst
(Radiographic)
- Usually appears as well‐circumscribed periapical radiolucency with widening of the PDL space and/or loss of lamina dura
- Typically small (< 1 cm) but can grow to large dimensions if left untreated
- Radiographic findings can NOT be used for definitive diagnosis
Why the Radiographic findings of Periapical Cyst can NOT be used for definitive diagnosis?
‐ similar appearance with:
- periapical granuloma
- odontogenic tumors
- early COD {Cemento Osseous Dysplasia}
Lateral radicular cyst appears on the lateral surface of the root of a non‐vital/non‐responsive tooth
‐ A differential for which cyst?
lateral periodontal cyst
What is this radiographic finding?
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Periapical Cysts
►Would need to test both teeth for vitality.
What is this radiographic finding?
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Periapical Cyst
What is this radiographic & clinical findings?
Periapical cyst
shows inflammation at site
abscess developed fistula tract thru
soft tissue. Pt will have pain until
pressure is released
The wall of which cyst?
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Periapical Cyst
Open clear areas = Cholesterol clefts where fat
used to be. Multinucleated cells (purple dots)
trying to break down cholesterol
What is this and what is it associated with?
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keratin pearl – can be associated w/SCC
Periapical Cyst
treatment
- endodontic therapy or extraction of involved teeth
- larger lesions may require biopsy along with endodontic therapy
- lesions which fail to resolve should be biopsied
- follow-up at 1-2 years
Residual Cyst
Etiology
- After tooth extracted, not properly cleaned ► the residual cells of the cyst lining and inflammatory cells continue to proliferate
- Has to be at site where tooth was previously removed
Residual Cyst
Radigraphically
- well defined round to oval radiolucency in the site of a previous extraction
Residual Cyst
Histologically is identical to which cyst?
- identical to the radicular cyst (periapical cyst)
- Should biopsy to rule out other causes
Residual Cyst
Treatment
-Removal
- Enucleation if small
- Marsupialization if large
- Note:*
- Enucleation* means: removal of an organ or other mass intact from its supporting tissues
Marsupialization means: surgical technique of cutting a slit into an abscess or cyst to empty its contents and suturing the edges of the slit to form a continuous surface from the exterior surface to the interior surface of the cyst or abscess.
Promotes Decompressing and shrinkage.
What are these radiographic findings?
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Residual Cysts
What is the radiographic finding?
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Residual Cyst
Paradental Cyst
Etiology
Some controversy over this designation
‐ some think they are inflammatory cyst
‐ some think they are developmental cysts
▪ Etiology: remains unclear
Paradental Cyst
Radiographically
- Radiolucent area noted
- most frequently, along the distal aspect of an impacted or partially erupted third molar
Which cyst has been associated w/ enamel extensions into furcation areas of the
involved teeth?
Paradental Cyst
Paradental Cyst
Treatment
Extraction of the tooth along with the lesion
What is the radiographic finding?
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Paradental Cyst
What is the radiographic finding?
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Paradental Cyst
Buccal Bifurcation Cyst
is similar to what Cyst ?
Similar to a paradental cyst
‐ EXCEPT: location is central on the buccal of mandibular first molars
Buccal Bifurcation Cyst
Etiology
unclear
Buccal Bifurcation Cyst is most commonly seen with eruption of what tooth?
The eruption of the permanent first molar
Buccal Bifurcation Cyst
Clinically
seen as
- swelling
- tenderness of soft tissue over involved area
Which
Radiograph type is best to see
Buccal Bifurcation Cyst?
▪ Radiolucency best seen with an occlusal radiograph
What is the radiographic finding?
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Buccal Bifurcation Cyst
as seen in occlusal radiographs
What is the radiographic finding?
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Buccal Bifurcation Cyst
as seen in occlusal radiographs
Buccal Bifurcation Cyst
Treatment
▪ Enucleation of cyst; tooth extraction unnecessary
▪ Some cases resolve w/o surgery
▪ Some resolve w/ daily irrigation of buccal pocket with saline/hydrogen peroxide
Dentigerous Cyst
also known as ?
Follicular Cyst
What is most common type of developmental odontogenic cysts?
20% of all epithelial lined cysts of the jaw
Dentigerous Cyst
Dentigerous Cyst
Origin & Etiology
Originates: by the separation of the follicle from the crown of an unerupted tooth
Pathogenesis: accumulation of fluid between the tooth and the reduced enamel epithelium
Dentigerous Cyst
Clinically
▪ Small cysts typically asymptomatic and picked up
on routine radiographic exam
▪ Large lesions may show expansion of bone
▪ Cysts may become infected, especially if partially erupted
tooth
Dentigerous Cyst
Demographics & Location
- Mostly mandibular 3rd molars (rarely unerupted deciduous teeth)
- Most commonly present in 2nd and 3rd decades
What is a key characteristic of Dentigerous Cyst location?
- Attached to the tooth at the CEJ
Small Dentigerous Cyst
are hard to differentiate radiographically from —?
enlarged/hyperplastic follicle
Rule of thumb:
- If 4‐5mm or more of radiolucency ► dentigerous cyst
- If <4mm of radiolucency► can be hyperplastic follicle
dentigerous cyst or
follicle ?
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_dentigerous cys_t
b/c *attachment at CEJ
What is the radiographic finding?
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Dentigerous Cyst
What are these radiographic findings?
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dentigerous cyst
What are these radiographic findings?
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dentigerous cyst
What is the radiographic finding?
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dentigerous cyst
What is this gross finding?
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Grossly image of
Dentigerous Cyst
Dentigerous Cyst
Treatment
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- Decompression: Try to open window in the jawand put tube into cyst lumen and have pt irrigate a few times a day for a few weeks ► release pressure and allows bone to grow back ► cyst will shrink
- If get rid of whole area surgically► c_an risk_ fracturing the jaw
What is the Soft tissue counterpart of a dentigerous cyst?
Eruption Cyst
Eruption Cyst also known as
eruption hematoma
Eruption Cyst
Etiology
- Results from accumulation of fluid in the follicular space when the tooth has erupted over the alveolar bone *NOT in bone*
Eruption Cyst
Demographic & Location
▪ Usually seen in 1st decade (children)
▪ Most often involves 1st permanent molar and maxillary incisors
Eruption Cyst
Clinically
Frequently normal mucosal color, BUT surface trauma (ex. chewing) may result in bleeding into the cystic space► may look purple or blue
▪ Usually soft or fluctuant(like a balloon) upon palpation
Eruption Cyst
Treatment
- Unless symptomatic, no treatment required, cysts resolve upon eruption of teeth
What is the clinical finding?
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Eruption Cyst
What is the clinical finding?
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Eruption Cyst
Cysts of the Newborn
can either be — or —
Palatal cysts
or
Gingival cyst
Palatal cysts
Types
&
Location
‐ Bohn’s nodules: scattered over HP (hard palate), often junction of HP and SP (soft palate)
‐ Epstein’s pearls: along median palatal raphe
Cysts of the Newborn:
Palatal cysts
Demographics
- Seen in 60‐80% of neonates
Cysts of the Newborn:
Palatal cysts
Clinically
- 1‐3 mm cream to white papules (keratin filled cysts)
*NOT in bone*
Cysts of the Newborn:
Palatal cysts
Treatment
No treatment is required
‐ Resolve (degenerate or rupture) on their own in a
few months
‐ Once baby eats solid foods, will go away
What is the clinical finding?
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Cysts of the Newborn:
Palatal cysts
Cysts of the Newborn:
Gingival cyst of the Newborn
Also known as
Dental lamina cysts
Gingival cyst of the newborn
demographics & Location
- Found superficially on the alveolar ridge mucosa
- MX > MD
- Rarely seen after 3 mos. of age
Gingival cyst of the newborn
Treatment
▪ No treatment is necessary
▪ Spontaneously resolve (degenerate or rupture)
Gingival cyst of the newborn
Clinically
- 1‐3 mm creamy white papule (keratin filled cysts)
- *NOT in bone*
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Gingival cyst of the newborn/ Dental lamina cysts/Cysts of the Newborn-gingival
What is the soft tissue counterpart of the lateral periodontal cyst ?
Gingival Cyst of the Adult
Gingival Cyst of the Adult
Origin
Derived from dental lamina rests
‐ Rests of Serres
Gingival Cyst of the
Adult
Demogrophic & Location
▪Uncommon lesion
▪ 60‐75% mandibular canine/premolar area
‐ most common location on the facial or buccal aspect
▪ 5th and 6th decade most common
Gingival Cyst of the
Adult
Clinically
- Painless, dome‐like swellings up to 5 mm in diamete
- Often with a bluish or grayish hue
Gingival Cyst of the
Adult
has similar histology to which cyst?
lateral periodontal cyst
Gingival Cyst of the
Adult
Treatment
- simple surgical excision
- Unlikely to recur/come back
What is the clinical finding?
Gingival Cyst of the
Adult
What is the clinical finding?
Gingival Cyst of the
Adult
What is the clinical finding?
Gingival Cyst of the
Adult
notice the bluish hue
Lateral Periodontal Cyst represents the intrabony counterpart of which cyst?
gingival cyst of the adult?
Lateral Periodontal
Cyst
Origins
- Developmental cyst believed to arise from dental lamina rests
Lateral Periodontal cyst is diagonsed when cysts occur in the lateral periodontal region and after what have been excluded?
- an inflammatory origin cysts or the diagnosis of odontogenickeratocyst have been excluded
Lateral Periodontal Cyst
Charcterstics and tooth vitality
▪ Commonly asymptomatic and found on routine radiographic exam
▪ Associated teeth tests vital/responsive with electric pulp test
if you see a radilucency Lateral to a teeth
how would you know if it’s
Lateral Periodontal Cyst
or
Lateral Radicular Cyst
or
Lateral OKc
‐ If pulp alive► lateral periodontal cyst or Lateral Okc ( if huge lesion)
‐ If pulp dead► lateral radicular cyst
Lateral Periodontal Cyst
Demographic and Location
▪ Most likely found after age 30
▪ Males>Females
▪ ~65% mandibular canine/premolar area
‐ Can also be seen between canine and lateral incisor
Lateral Periodontal Cyst
Radiographically
Present as well circumscribed, unilocular radiolucencies between 2 teeth, located lateral to tooth root
▪ Most often 0.5‐1.0 cm in diameter
▪ Radiographic features are NOT diagnostic
Which is here is
Lateral Periodontal Cyst
Lateral Radicular Cyst
Lateral Odontogenic Kertocyst
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- Could be differential for lateral Odontogenic keratocyst, except this does not grow in size
- Lateral radicular cysts from an accessory canal if tooth is non vital
- or it could be Lateral Periodontal Cyst if tooth is vital!
What is the radiographical finding?
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Lateral Periodontal
Cyst
What is the radiographical finding?
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Lateral Periodontal
Cyst
What is the histological finding?
Lateral Periodontal Cyst
see the alternating
thin to thick epithelium
a characteristic of these cysts
What is the histological finding?
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Lateral Periodontal Cyst
Lateral Periodontal
Cyst
Treatment
- consists of conservative enucleation
What cyst is a variant of lateral periodontal cyst?
Botryoid Odontogenic
Cyst
Botryoid Odontogenic
Cyst
Grossly and Microscopically
shows a grape‐like cluster of small
individual cysts
Botryoid Odontogenic
Cyst
Radiographically
▪ Either unilocular or multilocular on radiographs, depending on size of the lesion
▪ Cyst lining similar to lateral periodontal cyst
What is the radiographical finding?
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Botryoid Odontogenic
Cyst
well circumscribed, between 2 teeth (similar to
lateral odontogenic cyst), multilocular
What is the radiographical finding?
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Botryoid Odontogenic
Cyst
Glandular Odontogenic
Cyst
Charcterstics
- A rare odontogenic cyst which exhibits features of glandular differentiation within the epithelium
- Presumably represents the pluripotentiality of odontogenic epithelium
Glandular Odontogenic
Cyst
Demographics
▪ Wide age range from 2nd to 9th decades
‐ mean age 49
▪ ~ 80% of cases in mandible
▪ Anterior lesions
‐ More common
‐ May cross the midline
Glandular Odontogenic
Cyst
Radiographically
▪ Uni‐ or (more often) multilocular radiolucency
▪ Well‐defined with a sclerotic border
Glandular Odontogenic
Cyst
reccurance rate
(~ 25% recurrence rate)
Can be locally aggressive
Glandular Odontogenic
Cyst
Clinically
▪ Usually asymptomatic unless inflamed
“Primordial” Cyst
why it is controversial!
- Mixed up with OkC
- Originally meant to describe cyst which develops in bone at a site where a tooth was meant to develop (usually a third molar)
- If this lesion exists, it is truly rare and would have histology distinct from OKC
- In the current literature, reference has been almost nonexistent
What is the radiographical finding?
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“Primordial” Cyst
Assuming histologically it is different from OKC
“Primordial” Cyst
is not a true ——-
- lesion, was actually some other type of cyst
- it is now thought that most of the reported Primordial cysts were actually OKCs
Odontogenic
Keratocyst
OKC
Also known as
keratocystic odontogenic tumor (KOT) -2005 WHO
but now it’s back to OKC
Odontogenic
Keratocyst (OKC)
Etiology
- Growth and expansion of this lesion due not only to osmotic effects/pressure, but to unusual gene expressions
Which unusal gene expression causes growth and expansion of OKC ?
- Expresses Ki‐67 (high rate of cell proliferation)
- O_verexpression of Bcl‐2_ (antipoptotic protein)
- Overexpression of MMP’s 2 and 9 (thought to allow growth into connective tissue)
-
Mutation of PTCH, a tumor suppressor gene
- when PTCH is non‐functional → cell proliferation
Odontogenic
Keratocyst (OKC)
Demographic & Location
- ~ 60% present in 2nd and 3rd decade, but can occur at any age
-
Mandible affected in 60‐80% of cases
- tendency to occur in posterior mandible and ramus
- 25‐40% of cases involve an unerupted tooth
- ‐ 5% of patients have multiple cysts
Odontogenic
Keratocyst (OKC)
differes from
Meloblastoma
in its growth pattern
Odontogenic Keratocyst (OKC) :grows in anterior to posterior manner before causing cortical expansion
while
Meloblastoma: causes cortical expansion early
Which cyst make up ~10‐15% of all odontogenic cysts?
Odontogenic
Keratocyst (OKC)
5% of Odontogenic
Keratocyst (OKC) are associated with which syndrome?
nevoid basal cell carcinoma
syndrome(Gorlin syndrome)
What are the site distribution of OKC?
Most of OKC in
posterior region
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Odontogenic
Keratocyst
Reccurance Rate
- HIGH Recurrence Rate
- Benign, but locally aggressive biologic behavior
- Solitary OKCs have ~10% recurrence rate with appropriate treatment
- _Multiple OKCs hav_e ~ 30% recurrence rate
Odontogenic
Keratocyst
(OKC)
Reccurance Rate Order
from highest to lowest reccurance rate
Syndrome OKC > Multiple OKC > Solitary OKC > Conventional odontogenic cysts
Odontogenic
Keratocyst
OKC
Radiographically
- Usually a well‐circumscribed radiolucency with smooth, often corticated margins
▪ Cysts may be
‐ Unilocular (most common)
‐ Multilocular (larger lesions)
Odontogenic
Keratocyst
OKC
clinically
▪ Small cysts are typically asymptomatic and picked up on routine radiographic exam
▪ Larger cysts may or may not be asymptomatic
▪ *Cysts tend to grow in an antero‐posterior direction prior to lateral growth ►therefore cysts are usually quite large when they start to expand the cortical plate
Odontogenic
Keratocyst
OKC
Has similar Radiographic findings with ?
- dentigerous cyst
- ameloblastoma
- and others
Odontogenic
Keratocyst
OKC
Treatment
▪ Marsupialization (decompression)
▪ Peripheral ostectomy
‐ Carnoy’s solution
▪ Resection
▪ Medications targeted to PTCH
▪ Long term follow‐up
What is the radiographical finding?
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Odontogenic
Keratocyst
OKC
What is the radiographical finding?
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Odontogenic
Keratocyst
OKC
What is the radiographical finding?
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Odontogenic
Keratocyst
OKC
What is the radiographical finding?
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Odontogenic
Keratocyst
OKC
What is the radiographical finding?
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similar to
lateral
periodontal cyst
but is actually
OKC
What is the histological finding?
Odontogenic
Keratocyst
Histology
Notice the daughter cysts
Nevoid Basal Cell Carcinoma
Syndrome
is also known as —– ?
Basal Cell Nevus or Bifid Rib Syndrome
or
Gorlin syndrome
Which cyst is assoicated with
Nevoid Basal Cell Carcinoma
Syndrome
?
Odontogenic Keratocyst
“OKC”
Nevoid Basal Cell Carcinoma
Syndrome
(Gorlin syndrome)
_modes of inheritanc_e
Autosomal dominant inheritance
Which Gene mutation and pathway
associated with
Nevoid Basal Cell Carcinoma
Syndrome
(Gorlin syndrome)
- Mutation of PTCH (tumor suppressor gene)
- in the Sonic Hedge Hog pathway
Nevoid Basal Cell Carcinoma
Syndrome
Prognosis
■ Prognosis depends on progression of skin tumors
Nevoid Basal Cell Carcinoma
Syndrome
Treatment
✎Surgery (typically MOHS)
✎Sometimes curette them
✎ Radiation therapy (RT) is typically not the first line of therapy with small lesions RT
✎Cryotherapy which means they just use a little liquid nitrogen and freeze them
✎Photodynamic therapy with photosensitizer and topical medications
■ New medication: Vismodegib inhibits sonic hedgehog pathway by binding smoothened (SMO)
- suppressive rather than curative cause it seems to work for short time and after ~7-8 months ..may also helps suppress growth of OKC
What is this radiographic finding?
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✎A patient who has Nevoid Basal Cell Carcinoma
Syndrome
✎We can see multiple cystics areas and lesions in
the jaws, maxillary and mandible
✎Both 3rd molar displaced in the maxilla because of
the cyst
What is this radiographic finding?
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✎Multiple lesions, impacted 3rd molar in mandible
and displaced 3rd molar up into the sinus,
✎These too many lesions hard to manage the issue
with a surgery
✎This large area on the left mandible – good example of why we do
decompression because if you just remove this lesion
and the entire area is left open, this would be an area
risk for fracture
What is this called
which can be seen with
Nevoid Basal Cell Carcinoma
Syndrome
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✎An example of the pitting that can be seen palmar
and plantar
~ This is a side of a hand
✎This is an early stage of basal carcinoma which
never goes on (like it is aborted)
What are these findings that is associated with
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Nevoid Basal Cell Carcinoma
Syndrome?
- thousands of basal cell carcinoma is developing on the skin
-very difficult to manage with surgery,
~ That’s why they remove
the larger ones, the deeper ones ~ They leave the one
that’s less as an issue until they get to a larger size to
be removed
Why Basal Cell Carcinoma is very problematic ?
It’s not the lesion themselves causing metastasis
that’s the issue, it’s the lesion growing deeply and in affecting adjacent structures that really is the
issue with basal carcinoma
What is the Most common type of skin cancer?
Basal Cell Carcinoma
(BCC)
Basal Cell Carcinoma
(BCC)
Demographics
- 2-3 million cases a year
- About 3 out of 4 skin cancers are basal cell carcinomas
Basal Cell Carcinoma
Growth and location
(BCC)
- Develop in the lowest layer of the epidermis, called the basal Layer
- Develops on sun-exposed areas: cumulative DNA Damage
- Slow-growing
• If not treated, basal cell cancer can grow into nearby areas
and invade the bone or other tissues beneath the skin
Basal Cell Carcinoma
Progrssion
(BCC)
within 5 years of being diagnosed with
BCC►35%-50% of people develop a new skin cancer
Calcifying Odontogenic Cyst
COC
also known as
?
- Calcifying Cystic Odontogenic Tumor
- Gorlin Cyst ( don’t confuse it with Gorlin syndrome)
- Ghost Cell Tumor
*
Calcifying Odontogenic Cyst
(COC)
can present in 3 types
-
■ Cystic Unilocular COC
- COC with odontoma (~ 20%)
- Extraosseous/peripheral – present in older patients
-
■ Solid COC (odontogenic ghost cell tumor)
- Often demonstrate a more aggressive behavior
- WHO once considered them all CCOT now back to COC
- ■ Odontogenic ghost cell carcinoma
- very rare lesion
Collision Tumors is a term used to describe lesions involving Calcifying Odontogenic Cyst (COC), what does that mean?
- where you see both features of ameloblastoma with COC or adenomatoid odontogenic tumor with COC
Calcifying Odontogenic Cyst
(COC)
may occur in association
with
which tumors or cysts?
- Odontomas (a benign tumour linked to tooth development)
- Ameloblastomas (rare, noncancerous (benign) tumor)
- Adenomatoid odontogenic tumor (rare tumor of epithelial origin that is benign, painless, noninvasive, and slow-growing)
Calcifying Odontogenic Cyst
(COC)
Demographics & Location
■ Peak in second decade, most before age of 40
■ Frequently presents anterior to molars
■ ~ 20% extraosseous (peripheral), found in older age group (~ 50 years of age)
■ Female > Male
■ ~ 70% occur in MX
■ One third are associated with unerupted teeth, usually a canine
Calcifying Odontogenic Cyst
Radiographically
(COC)
■ Usually a well-circumscribed unilocular radiolucency, infrequent multilocular cases
■ One third to one half show radiopaque structures within the radiolucency
■ When you see calcifications within a lesion, you don’t use the term uni or multi locular anymore, but they are called mixed radiolucent/radiopaque lesions
■ May cause resorption or displacement of roots
■ One third are associated with unerupted Canine
What is this radiographic finding?
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**Calcifying Odontogenic Cyst (COC)**
- in the mandible and you can see it well circumscribed radiolucency
- a little bit of blunt root resorption in this area
- No calcifications in this one yet ►so this is still unilocular radiolucency
What are the clinical and radiographic findings here?
What is this lesion?
- Clinical finding for this patient was Obliteration of the vestibule space, because the mandible is showing expansion
- radiographically:we see radiolucency going as far as the first molar
- This is a mixed radiolucent radiopaque lesion in developing calcifications.
- This is an example of Calcifying Odontogenic Cyst (COC)
The hallmark of Calcifying
Odontogenic Cyst COC Histology is
Ghost cells
They have that sort of polygonal shape or roundish shape with the pink that looks like the cytoplasm, but in
the location where the nucleus would have then, there’s an empty spot
Histologically speaking, Calcifying
Odontogenic Cyst COC, basically
looks similar to what epithelium?
ameloblastic epithelium
Calcifying Odontogenic Cyst COC
Treatment
■Enucleation with peripheral ostectomy ~ Very similar to odontogenic keratosis
■ Follow up is long term because s_ome of the solid tumors have a more aggressive behavior_
■ Peripheral lesions are treated with excision
When COC is associated with another tumor, ameloblastoma, how would you treat?
■ the treatment is based on the more aggressive tumor
~ So you would treat the ameloblastoma.
~You wouldn’t treat conservatively the COC though
Odontogenic ghost cell carcinoma
Prognosis
(5 year survival ~ 70%).
- It is rare and shows cytologic atypia histologically
- It has an unpredictable biologic behavior