Bailey's Chapter 112 - Odontogenic Cysts Tumors

1. Which of the following is the most common inflammatory cyst?

Dentigerous Cyst

Odontogenic Keratocyst

Radicular Cyst

Nasopalatine Duct Cyst

Stafne Bone Cyst

The rest are actually developmental cysts.

Explanation

The rest are actually developmental cysts.

2. A middle aged male is seen for a slowly growing mass. It is located in the posterior portion of the mandible. It is asymptomatic and does not alter the sensory nerve function of the patient. Radiographically, the lesion is multilocular, with ill-defined borders. Histologically the specimen is seen below. What is the correct diagnosis?

Odontogenic Myxoma

Adenocarcinoma

Ameloblastoma

Odontogenic Keratocyst

Adenomatoid Odontogenic Cyst

The correct diagnosis is Ambelblastoma. The histology demonstrates a follicular pattern, with islands of odontogenic epithelium characterized by peripheral columnar cells exhibiting reverse polarity away from the basement membrane. The recurrence rate is as high as 90% if inadequately treated. However, when hard and soft tissue margins are negative, a cure rate of nearly 98% is achieved.

Explanation

The correct diagnosis is Ambelblastoma. The histology demonstrates a follicular pattern, with islands of odontogenic epithelium characterized by peripheral columnar cells exhibiting reverse polarity away from the basement membrane. The recurrence rate is as high as 90% if inadequately treated. However, when hard and soft tissue margins are negative, a cure rate of nearly 98% is achieved.

3. An 18yo F presents with the following:

.
She undergoes enucleation and curretage. Pathology demonstrates:

What is the correct diagnosis?

Odontogenic Myxoma

Adenocarcinoma

Ameloblastoma

Odontogenic Keratocyst

Adenomatoid Odontogenic Cyst

AOC's are the "two thirds tumor." 2/3 are in femails in their adolescent and teenage years. 2/3 are assoicated with an unerupted tooth, of which two-thirds are associated with a canine. two-thirds arrise in the maxilla. Radiographically the AOC usually is a well0circumscribed, unilocular radiolucency assoicated withan impacted tooth. Histologically, it is highly cellular with spindoehaped cells in whorls or rosettes. Recurrence is not seen in this benign encapsulated lesion, so curettage alone is curateive.

Explanation

AOC's are the "two thirds tumor." 2/3 are in femails in their adolescent and teenage years. 2/3 are assoicated with an unerupted tooth, of which two-thirds are associated with a canine. two-thirds arrise in the maxilla. Radiographically the AOC usually is a well0circumscribed, unilocular radiolucency assoicated withan impacted tooth. Histologically, it is highly cellular with spindoehaped cells in whorls or rosettes. Recurrence is not seen in this benign encapsulated lesion, so curettage alone is curateive.

4. A 24yo M comes to clinic for chronic postnasal drip. He has a frequent cough because of this. He has attempted many over the counter antihistamines with limited success. A referral to an allergist was made and after a negative skin test the following CT scan was obtained. He is referred to you for treatment of his sinusitis. What is the likely diagnosis?

Dentigerous Cyst

Nasopalatine Duct Cyst

Stafne bone Cyst

Fibroosseous Dysplasia

Radicular cyst

Although the CT scan might confuse you to think this is a nasopalatine Duct cyst, it is not in the midline. The incisince foramen is in the midline. The answer is not Radicular cyst because this is not inflamatory/acute in nature. The answer is dentigerous cyst. This would be quite difficult to answer if one of the answer choices was an Odontogenic Keratocyst due to the common similarities between the two.

Explanation

Although the CT scan might confuse you to think this is a nasopalatine Duct cyst, it is not in the midline. The incisince foramen is in the midline. The answer is not Radicular cyst because this is not inflamatory/acute in nature. The answer is dentigerous cyst. This would be quite difficult to answer if one of the answer choices was an Odontogenic Keratocyst due to the common similarities between the two.

5. A 15yo F presents with Right Maxillary Swelling.

The key findings associated with this disease include all of the following EXCEPT:

A wide range of recurrence from 5-60% depending on the surgical technique.

The preferred treatement is surgical enucleation and osseous curettage, removing the specimen in one piece.

When multiple lesions of this nature appear, one should consider the diagnosis of McCune-Albright Syndrome.

This is an example of an odontogenic keratocyst. Multiple OKC's are seen in Nevoid Basal Cell Carcinoma syndrome (Gorlin Syndrome).

McCune-Albright Syndrome is associated with polyostoti fibrous dysplasia.

Explanation

This is an example of an odontogenic keratocyst. Multiple OKC's are seen in Nevoid Basal Cell Carcinoma syndrome (Gorlin Syndrome).

McCune-Albright Syndrome is associated with polyostoti fibrous dysplasia.

6. Which of the following helps to separate a dentigerous cyst from an odontogenic keratocyst?

Amyloid deposition

Rushton bodies

Unerupted teeth

Ghost cells

Cortical expansion

A dentigerous cyst is the second most common odontoenic cyst. A Dentingerous cyst must be associated with the crown of an unerupted tooth, whereas an OKC can develop from the remnants of the dental lamina, and can occur in any jaw location. Addiontal differentiation of the OKC and dentigerous cysts are the OKC's aggressive growth, causing bony expansion and destruction and high recurrence rate.

Explanation

A dentigerous cyst is the second most common odontoenic cyst. A Dentingerous cyst must be associated with the crown of an unerupted tooth, whereas an OKC can develop from the remnants of the dental lamina, and can occur in any jaw location. Addiontal differentiation of the OKC and dentigerous cysts are the OKC's aggressive growth, causing bony expansion and destruction and high recurrence rate.

7. A 45yo F presents with swelling of the upper lip, pain on the maxilla, as well as sensitivity to cold. A CT scan is obtained. What is the correct diagnosis?

Periapical cyst

Dentigerous Cyst

Odontogenic Keratocyst

Nasopalatine Duct Cyst

Stafne Bone Cyst

With this history of pain and swelling, an infection is likely, and this would be consistent with a radicular cyst (otherwise known as a periapical cyst).

Explanation

With this history of pain and swelling, an infection is likely, and this would be consistent with a radicular cyst (otherwise known as a periapical cyst).

8. Unfortunately, the same child as above incorrectly undergoes segmental resection of the mandible one week later and we have the following histo slide to look at from the pathology. A characterisitic H&E stain of the specimen is shown below. The report indicates that the borders of the specimen are difficult to interpret due to surigical distortion (cutting) at the edges. Which of the following statements regarding this disease is FALSE?

The specimen exibits curvilinear portions of woven bone, sithout appositional osteoblasts, in a background of connective tissue stroma.

The patient is at an increased risk for sarcomatous transformation of the disease

The patient is likely to have other similar lesions in his longbones over the course of his life

Appropriate treatment would have been delayed contouring of the jaw after final growth has occurred.

This disease is a sporadic mutation in the alpha-subunit of a signal transducing G-protein

Fibrous displasia is mostcommonly the monostotic type *occuring in one bone. rarely is it polyostotic, unless it is a component of McCune-Albright syndrome which includes cafe-au-lait skin macules and multiple endocrinopathies, including hyperthyroidism or precocious puberty.

BTW, the pt is at an increased risk for sarcomatous transformation because the pt was operated on during an active growth phase

Explanation

Fibrous displasia is mostcommonly the monostotic type *occuring in one bone. rarely is it polyostotic, unless it is a component of McCune-Albright syndrome which includes cafe-au-lait skin macules and multiple endocrinopathies, including hyperthyroidism or precocious puberty.

BTW, the pt is at an increased risk for sarcomatous transformation because the pt was operated on during an active growth phase

9. A 14yo M presents with assymetrical swelling of his lower jaw. It is non-tender and has been progressively assymetric for the last year at least. On physical exam all cranial nerves are intact. His occlusion is minimally displaced. A CT Scan of a representative sample is shown below. Which of the following would be the best treatment option?

Observation with close follow up

Segmental resection of the mandible with postoperative radiation

Recontouring of the jaw surgically and orthodontics to correct malocclusion

Enucleation of the cyst with osseocurretage

This is an example of Fibrous Dysplasia. Fibrous dysplasia is not a true neoplasm, rather it is a tumor like condition where normal medullary bone is replaced with fibrous ocnnective tissue mixed with irregular bony trabeculae. Treatment includes recontouring of the affected jaw, and surgery is usually delayed until the affected bone has reached maturity.

Explanation

This is an example of Fibrous Dysplasia. Fibrous dysplasia is not a true neoplasm, rather it is a tumor like condition where normal medullary bone is replaced with fibrous ocnnective tissue mixed with irregular bony trabeculae. Treatment includes recontouring of the affected jaw, and surgery is usually delayed until the affected bone has reached maturity.

10. A 30yo M presents for a slowly growing lesion on the side of his temple. It is pearly colored and smooth. It is non ulcerative and non-tender, but has been changing in shape and he is concerned because his father and aunt both have a history of recurrent skin cancer. PSHx is significant for three oral surgeries for "cysts in his jaw", with no reactions to anesthesia. Excisional biopsy is performed resulting in the following:

What other findings/problems is this patient at increased risk for having (select 3)?

Early onset chronic obstructive pulmonary disease

Cataract formation

Calcification of the falx cerebri

Palmar and plantar pitting

Meduloblastoma

Although not discussed in this text, meduloblastoma is seen in 5% of patients with Nevoid Basal Cell Carcinoma Syndrom (Gorlin Syndrome). Nevoid Basal Cell Carcinoma Syndrome is an autosomal dominant inherited condition that exhipts high penetrance with variable expressivity. It is a result of a mutation of the PTCH tumor suppresor gene. Interestingly, once adulthood is reached, the formation of new OKC is less problemeatic and the risk of BCC rises. Treatment of the basal cell carcinomas and the OKC's does not differ from those individuals without this disease.

Explanation

Although not discussed in this text, meduloblastoma is seen in 5% of patients with Nevoid Basal Cell Carcinoma Syndrom (Gorlin Syndrome). Nevoid Basal Cell Carcinoma Syndrome is an autosomal dominant inherited condition that exhipts high penetrance with variable expressivity. It is a result of a mutation of the PTCH tumor suppresor gene. Interestingly, once adulthood is reached, the formation of new OKC is less problemeatic and the risk of BCC rises. Treatment of the basal cell carcinomas and the OKC's does not differ from those individuals without this disease.

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11. Unlike fibrous dysplasia, ossifying fibromas are true tumors of mesenchymal origin that have strong predilection for the tooth-bearing portion of the jaws. Which of the following statements ARE TRUE regarding these tumors (select 2)?

Their radiologic appearance is similar throughout the life of the disease process

In the mandible, they typically appear as a midbody growth at the medial border.

The juvenile form is more common and is benign

The juvenile form has a predilection for the maxilla

It is usually well demarcated

Ossifying fibromas are usually well demarcated, benign lesions that present in middle aged women. An immature lesion initally presents as a radiolucency (hence the fibroma in the name) and then becomes more mixed, and eventually can become completely radiopaque ("ossifying") as it ages. The usual location is at the inferior border of the mandible, thus giving it the "hanging off the lower lateral border" appearance. The juvenile form is rare and has a more aggressive course. It does have a predilection for the maxilla.

Explanation

Ossifying fibromas are usually well demarcated, benign lesions that present in middle aged women. An immature lesion initally presents as a radiolucency (hence the fibroma in the name) and then becomes more mixed, and eventually can become completely radiopaque ("ossifying") as it ages. The usual location is at the inferior border of the mandible, thus giving it the "hanging off the lower lateral border" appearance. The juvenile form is rare and has a more aggressive course. It does have a predilection for the maxilla.

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