Oral Pathology

Question 1

Odontogenic Cysts definition

Answer 1

Cysts derived from the tissues involved in odontogenesis

Question 2

Dentigerous Cyst

Answer 2

Accumulation of fluid between the reduced enamel epithelium and the crown of the tooth.
Variants
1. Central - cyst surround entire crown attached to CEJ
2. Lateral - cyst grows lateral along lateral aspect of tooth
3. Circumferential - cyst surround the tooth

Tooth most commonly involved
- Mand third
- Max cuspid
- Max third
- Mand second premol

Can cause bony expansion, root displacement and resorption

Radiographic appearance
Well-delineated unilocular or multilocular radiolucency

Treatment
Enucleation
Large lesions (marsupialization then enculeation after decompression)
Uncommon recurrence

Question 3

Periapical cyst (radicular cyst)

Answer 3

Sequela of chronic inflammation in preexisting periapical granuloma
Normally seen at the apex of non-vital teeth
Most common cyst of jaw bones

Radiographic appearance
Well-circumscribed unilocular radiolucency around the apex of tooth

Treatment
Endo/Endo with apicoectomy
Extraction with curettage of socket

Question 4

Residual Cyst

Answer 4

Cyst that has been left in the jaw bone after associated tooth has been extracted (most common in maxilla)

Radiographic appearance
Well-circumscribed radiolucency

Treatment
Simple excision

Question 5

Lateral periodontal cyst

Answer 5

Arises in periodontal ligament along lateral aspect of the root of the tooth
Teeth are vital
Most common in canine-premolar region of mandible or lateral incisor canine region of maxilla
Has a polycystic variant known as the botryoid-odontogenic cyst (grape-like clusters)

Radiographic appearance
Well-defined (unilocular or multilocular) radiolucency along lateral surface of tooth root

Treatment
Enucleation

Question 6

Glandular Odontogenic Cyst

Answer 6

Rare cyst that can be clinically aggressive (expansion, pain, paresthesia)
Anterior mandible usually crosses midline
Can have features of a low-grade mucoep

Radiographic appearance
Well defined unilocular or multilocular radiolucency surround by sclerotic border

Treatment
Curettage
Some advocate for marginal or en bloc resection due to high recurrence (30%)

Question 7

Odontogenic Cysts List

Answer 7

Dentigerous Cyst
Periapical Cyst (Radicular Cyst)
Lateral periodontal cyst
Glandular Odontogenic Cyst
Odontogenic Keratocyst (OKC)
Calcifying Odontogenic Cyst (Gorlin Cyst)

Question 8

Odontogenic Keratocyst (OKC)

Answer 8

Derived from rests of dental lamina (rests of Serres)
Associated with PTCH tumor suppressor gene
More common in mandible (third molar region)
Aggressive with high tendancy to recur in the first 5 yeras
Will displace nerve and resorb teeth

May be associated Nevoid Basal Cell carcinoma syndrome (Gorlin Syndrome)
- Multiple Basal Cell Carcinomas
-Multiple OKC’s
-Palmar and plantar pits
-Calcified falx cerebri
-Rib anomalies (bifid, missing, partially developed)
-Spina Bifida
-Hypertelorism
-Enlarged head circumference due to frontal bossing
-Cleft lip and palate

Radiographic appearance
well-defined unilocular or multilocular radiolucency bounded by corticated margins usually with displacement or resorption of teeth

Treatment
Enucleaction and curettage with peripheral ostectomy.
Large cysts can be decompressed prior to treatment
Cryotherapy with liquid nitrogen offers penetration up to 1.5 mm into the bone.
Chemical cauterization - Carnoy’s solution (ethanol, chloroform, glacial acetic acid, ferric chloride). This form is banned due to chloroform being a carcinogen. Modified form without chloroform but recurrence rate is considerably higher since chloroform is essential for its successful use

Question 9

Calcifying Odontogenic Cyst (Gorlin Cyst)

Answer 9

Odontogenic epithelial remnants that were trapped within the bone or gingival tissues
Most cases are within bone and found in second or third decade

Radiographic Appearance
a unilocular, lucent lesion with smooth, corticated borders that is often associated with an impacted tooth

Treatment
Conservative removal with low recurrence rate

Question 10

Odontogenic Tumors

Answer 10

Neoplasms derived from tissues that are involved in odontogenesis

These include:
Ameloblastoma
Unicystic ameloblastoma
Peripheral ameloblastoma
Malignant ameloblastoma
Ameloblastic fibroma
Ameloblastic Fibrosarcoma
Ameloblastic Fibro-Odontoma
Calcifying epithelial odontogenic tumor (pindborg tumor)
Adenomatoid Odontogenic Tumor
Odontogenic Myxoma
Odontoma (compound and complex)
Cemento-Ossifying Fibroma (Ossifying Fibroma)
Cementoblastoma

Question 11

Ameloblastoma

Answer 11

originates from the residual odontogenic epithelium
Most common in mandible and can cause jaw expansion
High rate of recurrence

Radiographic appearance
Well defined borders that are uilocular or multilocular radiolucency with soap-bubble appearance often referred to as honeycomb
May simulate a dentigerous cyst

Histological subtypes
Follicular - most common from odontogenic epithelium
Plexiform - interconnected elongated islands of epithelium
Acanthomatous - Squamous metaplasia in center of ep islands
Granular cell - Eosinophilic granular cells
Desmoplastic - Well-collagenized stroma (mimcs fibro-osseous lesion)

Treatment
Marginal or block resection - curative using 1.0-1.5 cm bony margins and one uninvolved anatomical margin.

Question 12

Unicystic Ameloblastoma

Answer 12

13-21% of all cases of ameloblastoma
Slow growing, paresthesia uncommon

3 histological variants
Unicystic
Intraluminal
Mural

If extraluminal invasion then normal marginal resection
If intraluminal then E&C with long term follow up

Question 13

Peripheral Ameloblastoma

Answer 13

Arises from rests of dental lamina or basal cell layer of surface epithelium
Exophytic mass of the tooth bearing area
Does not normally invade bone
Less agressive than intraosseous counterpart

Local surgical excision with 2-3 mm margins

Question 14

Malignant Ameloblastoma

Answer 14

Metastasizes but metastatic deposits are benign
Less than 1% of ameloblastoma
Most metastasize to lungs followed by cervical lymph nodes

Malignant ameloblastoma
Treatment - En bloc resection of primary tumor with wedge resection of the lung and possibly chemotherapy.

AMELOBLASTIC CARCINOMA -
histologically malignant with hyperchromatism, increased nuclear-to-cytoplasmic ration presence of high mitosis

Treatment - resection with 2-3 cm bony leions with neck dissection. Consider chemoradiation

Question 15

Calcifying Epithelial Odontogenic Tumor (Pindborg Tumor)

Answer 15

Arise from odontogenic epithelium
Commonly in premolar region
Slow painless expansion

Radiographic appearance
Well delineated, bu may have ill-defined borders in 20% of them. Unilocular or multilocular radiolucency.
Can show expansion and association with an impacted tooth
Calcified structures (Liesegang ring calcifications can be seen within the lesion. Amyloid-like material is found within the stroma)

Treatment
Conservative local resection with peripheral ostectomy with recurrence rate of 15%
May advocate fro resection with 1-1.5 cm margins

Question 16

Adenomatoid Ondotogenic Tumor

Answer 16

2/3rds lesion (female, anterior maxilla, impacted canines)
Slow growing and asymptomatic
Thick fibrous capsule

Radiographic findings
expansile radiolucency with well-circumscribed margins that are unilocular and have snowflake-like calcifications

Treatment
Conservative enucleation and are removed easily from bed due to thick fibrous capsule

Question 17

Odontogenic Myxoma

Answer 17

Arises from odontogenic ectomesenchyme
More commonly in mandible than maxilla
Can cause expansion and displacement/resorption of teeth
Myxoid stroma containing spindle and stellate-shaped cells

Radiographic appearance
Multilocular radiolucency as well as soap bubble, tennis-racquet and honeycomb patterns

Treatment
Resection - curative form of treatment 1.0-1.5 cm margins and one uninvolved anatomical margin
Curettage - small lesions and palliative care

Question 18

Cemento-Ossifying Fibroma (Cementifying or Ossifying Fibroma)

Answer 18

Form of ossifying fibroma confined to tooth-bearing area of jaws
Female and third-fifth decade
Most common mandible
Slow growing, painless, may cause large expansion

Radiographic appearance
Well circumscribed round radiolucent or radiopaque lesion with displacement of teeth

Treatment
Conservative enucleation for a small, well-demarcated lesion usually encapsulated
Large lesions require resection with 5 mm borders. No need to remove involved soft tissue as tumor is encapsulated

Question 19

Cementoblastoma (True Cementoma)

Answer 19

Solitary lesion found in continuity with a tooth root
Normally vital teeth
Mandibular premolar or molar
less than 30 yrs old
May have expansion and discomfort

Radiographic appearance
Well-defined dense radiopaque mass in continuity with tooth root with radiolucent halo around the lesion
Periodontal ligament space surrounds the mass to distinguish from hypercementosis

Treatment
Excision often with loss of involved tooth
May consider endo treatment with root resection

Question 20

Ameloblastic Fibroma

Answer 20

First and second decade in males. Posterior mandible. Bony expansion

Radiographic appearance
Unilocular or multilocuar radiolucency with well-defined borders. Commonly associated with unerupted tooth
Cortical expansion is common

Treatment
Conservative surgical excision is recommended
More aggressive excision for recurrent lesions
Ameloblastic fibrosarcoma may develop in setting of recurrences

Question 21

Ameloblastic Fibrosarcoma

Answer 21

Third decade in mandible
Rapid growth with pain and swelling
Malignant counterpart to ameloblastic fibroma
May arise de novo or from pre-existing ameloblastic fibroma

Radiographic appearance
Poorly defined destructive radiolucency that is unilocular or multilocular with expansion

Treatment
Radical surgical excision with 1.0-1.5 cm margins. Lesions dont usually metastasize, but patient may die from uncontrolled local disease

Question 22

Ameloblastic Fibro-odontoma

Answer 22

Younger population in mandible, developmental stage of odontoma

Radiographic appearance
Well-defined unilocular or multilocular lesion with calcifications associated with unerupted tooth

Treatment
Enucleation and curettage

Question 23

Odontoma

Answer 23

May be found associated with tooth that has failed to erupt
Most common odontogenic tumor.

Radiographic appearance
Compound odontoma appears as small tooth like structure often surround by radiolucent halo
Complex odontoma: radiopaque mass surrounded by radiolucent rim

Treatment
Excision

Question 24

Fibro-Osseous Lesions

Answer 24

Disease processes characterized by normal bone being replaced by fibrous tissue containg a mineralized product

Fibrous dysplasia
Cemento-Osseous Dysplasia
Central Giant Cell Tumor
Peripheral Giant Cell Granuloma

Question 25

Fibrous dysplasia

Answer 25

Normal bone being replaced by fibrous tissue associated with GNAS mutation/deletion
Can involved one bone (monostotic) if late mutation or multiple (monostotic) bones if early mutation

Monostotic disease:
-Most common involved in craniofacial bones, ribs, femur and tibia
-Slow, painful growth of jaw. Adjacent teeth may be displaced by expansion
-Maxillary lesions can obliterate the antrum if extensive enough
-Lesion stabilize after skeletal maturation and even regress in some cases

Polystotic diseases: usually associated with syndromes that have cutaneous and endocrine abnormalities
- Jaffe- Lichtenstein syndrome has cafe au lait pigmentation
-McCune albright syndrome with cafe au lait pigmentation and endocrinopathies like precicious puberty, hyperparathyroidism, hyperthyroidism, and hypercortisolism
-Mazabraud syndrome with intramuscular myxomas

Radiographic appearance
Ground glass opacity with poorly defined margins including ill-defined lamina dura

Treatment
Conservative management is treatment of choice
Surgical controuing if severe cosmetic deformities
Orthodontic treatment and orthognathic surgery for malocclusion
High concern for blood loss after surgery
Radiation contraindicated due to post radiation sarcoma
Bisphosphonates may help relieve bone pain but risk for MRONJ

Question 26

Cemento-Osseous Dysplasia

Answer 26

Black females 4-5th decade with vital teeth

Radiographic and clinical findings
Black female with multiquadrant or lower anterior teeth involvement where bone is replaced by cementum-like material

Three variants
Focal: Involves single site, posterior mandible, radiolucent to mixed to radiopaque
Periapical: Anterior mandible, black, radiolucent and mimic periapical granulomas or cysts. They mature and become mixed radiopacity and radiodense
Florid: Can involve all four quads, black, may develop swelling if simple bone cyst occur in long standing lesions

Diagnosis: Vital teeth, radiographic and clinical findings match

Treatment:
No surgical removal
Sclerotic lesions are hypovascular so they are prone to necrosis and infection from traumatic insults
Prevent dental disease leading to tooth loss
Patient with osteomyelitis should undergo debridement with saucerization

Question 27

Central Giant Cell Tumor

Answer 27

Unknown origin, Intraossesous lesion, nonaggressive or aggressive, mandible, routine radiographic discovery
Aggressive subtypes results in pain, paresthesia, root resorption, tooth displacement
1. Major: greater than 5 cm, recurrence after treatment
2. Minor: Rapid growth, clinical displacement or loosening of teeth, cortical thinning or perforation, radiographic evidence of tooth resorption or displacement

Similar to brown tumors of hyperparathyroidism.
PTH assay for primary hyperparathyroidism levels (with hypercalcemia)
Secondary hyperparathyroidism (with hypocalcemia)
Alkaline phosphatase elevation not necessarily needed to be assayed.

Histology
CGCs multinucleated giant cells within a spindle mononuclear cell stroma

Radiographic features
Well delineated unilocular or multilocular radiolucency with displaced teeth and resorption of interradicular bone

Treatment
E&C with peripheral ostectomy. Recurrence 20% or higher in large lesions
En bloc resection with 1 cm margins for recurrent lesions

Conservative treatment for large lesions:
-Intralesional corticosteroid injections - 1:1 mixture of local anesthestic and triamcinolone 10 mg/mL weekly for 6 weeks. 2 cc for every 1 cc of lesions visible on pano, high recurrence rate
-Submucosal or nasal calcitonin: 100 units/day 6 months.
-Subcutaneous interferon alpha-2a. In conjunction with curettage and postoperative treatment for 6 months
-Imatinib - tyrosine kinase inhibitor
-Bisphosphonates
-Rank-L inhibitor Denosumab showing to be effective

Question 28

Peripheral giant cell granuloma

Answer 28

Soft tissue variant caused by trauma or irritation
Part of the 3 Ps
1. Pyogenic granuloma
2. Peripheral Ossifying Fibroma
3. Peripheral Giant Cell Granuloma

Smaller than 2 cm with sessile or pedunculated base with blue/purple color

Treatment
Excision down to the bone

Question 29

Medication Related Osteonecrosis of Jaw (Drugs and Radiographic appearance)

Answer 29

Antiresorptive medications and antiangiogenic medications with exposed bone for more than 8 weeks that can be probed through an intraoral or extraoral fistula in the maxilla or mandible. No history of radiation therapy or obvious metastatic disease to the jaws

Bisphosphonates and RANK ligand inhibitors are antiresorptive medications
- Diminish or alter osteoclasts

• RANK ligand inhibitors prevent osteoclast differentiation
  Denosumab (Prolia) - for osteoporosis. Subcutaneous route
  Denosumab (Xgeva) - for bone metastasis. Subcutaneous route
• Bisphosphonates inhibit osteoclast function and increase apoptosis of osteoclasts
  Alendronate (Fosamax) - Osteoporosis. Oral route
  Risendronate (Actonel) - Osteoporosis. Oral Route
  Ibandronate (Boniva) - Osteoporosis. Oral or IV route
  Zolendronate (Reclast) - Osteoporosis. IV route
  Zolendronate (Zometa) - Bone Metastases. IV route
  Pamidronate (Aredia) - Bone Metastases. IV route

Antiangiogenic Medications reports indicate low risk for MRONJ
-Tyrosine Kinase inhibitors
-Monoclonal Antibodies inhibiting VEGF

Radiographic Appearance
Changes seen before clinical evidence of necrosis including radiopacity in areas of increased bone remodeling
Periosteal hyperplasia
Moth eaten radiolucency with central sequestra

Question 30

MRONJ Staging System

Answer 30

Stage 0 - Non exposed bone variant
Stage 1 - Exposed and necrotic bone or fistulae that probe to bone in asymptomatic patients with no infection
Stage 2 - Exposed and necrotic bone or fistulae that probe to bone in symptomatic patients with evidence of infection
Stage 3 - Exposed and necrotic bone or fistulae that probe to bone in symptomatic patients with evidence of infection and one or more of the following:
- Exposed necrotic bone extending beyond alveolus
-Pathologic fracutre
-Extra-oral fistula
-Oral antral/oral nasal communication
-Osteolysis extending to inferior border of mandible or sinus floor

Question 31

MRONJ Preventative Management and Treatment

Answer 31

Sources of dental infection eliminated prior to starting treatments. Takes 1 month after extractions or restorations before ready for medication treatment.
Bisphosphonates for 4 years or more as well as systemic corticosteroids or antiangiogenic agents, a DRUG HOLIDAY should be considered beginning 2 months prior to surgery and holding until healing complete. Drug holiday is not necessary for osteoporosis patients on bisphosphonates for less than 4 years

Treatment
Removal of bony sequestrum
Pain management, antibiotics (penicillin, if allergic then fluoroquinolones, metronidazole, doxycycline, or erythromycin), antimicrobial rinses, debridement with possible resection for severe cases.

Question 32

Osteoradionecrosis of Jaws (Risk factors, findings, Radiographic appearance, Marx theory)

Answer 32

Radiation therapy for head and neck cancer. Irradiated bone exposed through a wound in overlying skin or mucosa and persists without healing for 3-4 months
Diagnosis requires proven necrotic bone not related to other causes.
Risk for developing following radiation ranges from 5%-15% with cases 4 months to 3 years after completion of therapy.

Risk factors
Radiation dose greater than 60 Gy
Primary tumor located in tongue, floor of mouth, alveolar ridge, retromolar triangle or tonsil
Satge III or IV cancer with mandibulectomy or ostectomy
Perio disease, poor oral hygiene, dental extractions after radiation, alcohol and tobacco use, poor nutrition

Clinical Findings
Trauma such as tooth extractions, but some spontaneous
Focal area of mucosal breakdown with exposure of bone. Progression into neuropathic pain, trismus, chronic drainage, dysgeusia, dysphagia, decreased tongue mobility
Eventually lead to pathologic fracture

Radiographic appearance
Pano will show poorly demarcated sclerotic radiolucent with intermixed lytic areas. Pathological fracutre may be seen
CT could show hypodense/hyperdense changes and interruptions in cortical margins

Marx theory of ORN - 3 H’s include Hypovascular, hypocellular, hypoxic tissue. Mandible is less vascularized than other bones which is why we see it more often

Question 33

Osteoradionecrosis (prevention and treatment)

Answer 33

PREVENTION
Avoid tooth extraction during or following radiation
-Extractions prior would include: extensive decay or infection, partially impacted, pocket depths more than 5 mm
-2-3 weeks healing before radiation initiation. Extractions can be done within 4 months following completion of radiation therapy if necessary. Within 5-6 months progressive fibrosis and loss of vascularity
-Stress importance of oral hygiene (high fluoride tooth paste, fluoride treatment with custom tray)

Hyperbaric Oxygenation
-Part of Marx’s theory that ORN cause by hypoxia, hypocellularity, hypovascularization
-HBO therapy increases oxygenation by stimulating angiogenesis, fibroblast proliferation, collagen formation which lead to healing.

TREATMENT
-30 HBO dives then re-evaluated. Improvement include decrease in amount of exposed bone, granulation tissue formation, re-mucosalization. May do another 30 as needed.
-No improvement after HBO dives, advanced to trans-oral debridement or sequestrectomy with primary mucosal repair.
-If recurrent bone exposure after HBO and surgery, patient will require resection to bleeding bone with primary wound close and fixation. Then dives until closure or a total of 60 dives completed.
-Reconstruction after disease is under control
-Pentoxyfylline (improves the flow of blood through blood vessels) and tocopherol (Vitamin E) for prevention and treatment

Question 34

Cutaneous Melanoma (What is it, risk factors, how to identify)

Answer 34

Malignant neoplasm of melanocytic origin. Melanocytes are pigmented dendritic cells at base of epidermis
Can arise de novo or from melanocytic nevus (benign counterpart)

RISK FACTORS
UV radiation
fair complexion
light hair or eyes
Family history
History of dysplastic or excessive nevi
Tanning bed usage
White adult around 60

Can resemble melanocytic nevus, ABCDE mneumonic
A- asymmetry
B- Border irregularity, scalloping, poor definition
C- Color variegation
D- Diameter greater than 6 mm in size
E- evolving, change in size, shape or color

Question 35

4 major types of Melanoma

Answer 35

1. Superficial spreading
   - most common and found on trunk and extremeties. Tan, brown, pink, blue. Sharply marginated outline with peninsula-like protrusions. Papule or nodule extends above surface
2. Lentigo Maligna
   - Large and mostly flat, tan, black and brown flecks of color with irregular outline. Commonly on face and neck
3. Nodular
   - Uniform brown-black or blue-black color with smooth surface nodule, elevated plaque with irregular outlines or ulcerated tumor. Trunk and extremities
4. Acral Lentiginous Melanoma
   - rare on palms, soles, mucous membranes, nail beds on Africans or Asian. Most common form of Oral Melanoma. Worse prognosis than other subtypes

Question 36

Cutaneous Melanoma Prognosis (chart and tumor staging, gene therapy)

Answer 36

Prognosis most closely linked to primary tumor thickness
Breslow depth chart measures mm of tumor cell depth from granular layer to base of melanoma

Breslow chart
Melanoma in-situ - 0.5 cm margin of resection
< or equal to 1 - 1 cm resection
1.01 - 2.0 mm - 1-2 cm resection
>2 mm - 2 cm resection

-Surgical margins based on Breslow depth. If depth greater than 4 mm or with ulceration, sentinel lymph node biopsy is recommended. Radiation therapy used for tumors with high suspicion of recurrence.

-TNM
T- Tumor thickness
N- Ulceration/mitosis
M - Metastasis

BRAF mutations involved in 50% of cutaneous melanomas. BRAF inhibitor treatments include. These are for metastatic melanoma
- Vemurafenib
- Ipilimumab

Question 37

Mucosal Melanoma (what is it, diagnosis, and radiographs needed

Answer 37

Rare and aggressive malignancy with primary in Head and Neck
Mainly in oral cavity, nasal cavity, paranasal sinuses, pharynx, larynx

RISK FACTORS
No associated with UV exposure, but inhaled and ingested carcinogens such as smoking and formaldehyde may play role.

DIAGNOSIS
CT and MRI used to define extend of tumor
- Enhancing, expansile, benign-apperaing destructive mass. May see moth-eaten irregular destructive resorption pattern on radiography
PET/CT used for staging
Must get chest xray to rule out metastasis
Can use ABCDE to distinguish between melanoma, racial pigmentation, amalgam tattoo, Peutz-Jeghers syndrome (the combination of skin hyperpigmentation and polyps in the gastrointestinal tract. The pigmentation consists of clusters of black-brown freckles about the lips, the buccal mucosa, and the perianal and genital area), Addison disease

Oral mucosal melanoma with widespread or multiple pigmented lesions with ill-defined borders. (Acral Lentiginous Melanoma most common form)
- Most common locations are maxillary alveolar ridge and hard palate

Question 38

Mucosal Melanoma of head and neck TNM classification

Answer 38

PRIMARY TUMOR (T) starts at T3
T3- Mucosal disease limited to mucosa and immediate underlying soft tissue regardless of thickness of greatest dimension.
T4 - Moderately advanced or very advanced
T4a - Tumor invading deep soft tissue, cartilage, bone, or overlying skin
T4b - very advanced involving brain, dura, skull base, lower cranial nerves, masticator space, carotid artery, prevertebral space, mediastinal structures

REGIONAL LYMPH NODES (N)
Nx - unable to assess lymph nodes
N0 - No regional lymph node metastases detected
N1- Regional lymph node metastases present

DISTANT METASTASES
M0 - no distant metastases
M1 - Distant metastases

Question 39

Mucosal Melanoma Treatment

Answer 39

Complete surgical resection with wide diessection of 3 cm with Primary mucosal melanoma
Lymph node dissection with evident regional metastasis. Can perform sentinel lymph node biopsy to identify patients who would benefit from elective neck dissection
Radiation therapy when patient is poot surgical candidate or margins are inadequate.
Chemotherapy as palliative care. No increase in 5 years survival

Question 40

Basal Cell Carcinoma (BCC) What is it, risk factors, pathogenesis

Answer 40

Most common cancer that rarely causes death or results in metastasis
Can be locally aggressive
40+ yr old male with 80% on head and neck

Risk Factors
UV radiation - recreational exposure to sun during childhood and adolescence
Fair complexion, red or blonde hair, light eye color
Immunosuppression
Radiotherapy treatment
Exposure to arsenic or tar

Pathogenesis
Inappropriate activation of the sonic hedgehog signaling pathway. This protein binds to and inactivates the PTCH1 tumor suppressor gene on chromosome 9q22. Germline mutation of PTCH1 are found in patients with nevoid basal cell carcinoma syndrome. Gorlin syndrome is autosoma dominant disorder, but around 40% of cases represent a new mutation.

Question 41

Basal cell carcinoma three main subtypes

Answer 41

Nodular - most common with shiny pearlescent nodules. May be crusting with central depression or ulceration with rolled border.

Superficial - well-circumscribed, scaly, pink-red macules or plaques with a crust or thin rolled border. Trunk and extremeties

Morpheaform - rarest type representing 5-10%. Indurated plaques, ill defined borders. Difficult to identify, and are usually more aggressive.

Question 42

BCC Staging, Treatment, High Risk

Answer 42

Tx - primary tumor cannot be assessed
Tis - Carcinoma in situ
T1 - Tumor 2 cm or less in greatest dimension
T2 - Tumor > or = 2 cm and <4 cm in greatest dimension
T3 - Tumor > or = 4 cm in greatest dimension and/or perineal invasion and/or deep invasion and/or minor bone erosion
T4a - Tumor with gross cortical bone/marrow invasion
T4b - Tumor with skull base invasion and/or skull base foramen involvement

Regional Lymph nodes (N)
Nx - regional nodes cant be assessed
N0 - No regional lymph node metastases
N1 - Metastasis in a single ipsilateral lymph node. < or = 3cm in greatest dimension and no extranodal extension
N2a - Metastases in a single ipsilateral lymph node > 3 cm but not > 6 cm in greatest dimension and no ENE
N2b - Metastases in a single ipsilateral lymph node, > 6 cm in greatest dimension and no ENE
N2c - Metastasis in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension and no ENE
N3a - Metastasis in a lymph node > 6 cm in greatest dimension and no ENE
N3b - Metastasis in single ipsilateral node > 3 cm in greatest dimension with ENE, or multiple ipsilateral, contralateral, or bilateral nodes, any with ENE; or a single contralateral node < or = 3 cm and ENE

Distant Metastases (M)
Mx - distant metastasis cannot be assessed
M0 - No distant metastases
M1 - Distant metastases

TREATMENT
Complete removal of tumor. Low risk of recurrence if treated with electrodessication and curettage or surgical excision.
Radiation may be used for patient unable to have surgery

RISK
High risk features include: lesion of 6 mm or more in mask area of face
Lesion more than 1 cm in head and neck
Lesions poorly defined
Perinerual invasion
Recurrent lesions
Immunosuppressed patients
Aggressive growth pattern.

Question 43

Squamous Cell Carcinoma (Lymphatic drainage)

Answer 43

Primary lymphatic drainage of ORAL CAVITY is upper cervial lymph nodes including:
Level 1a - submental nodes
Level 1b - submandibular nodes
Level 2 - upper jugular nodes
Level 3 - Middle jugular nodes
Level 4 - Lower jugular nodes: Up to 15% of tongue carcinomas can have “skip metastasis” to level 4 without involving 1,2 and 3.

Selective lymphadenectomy called “Supraomohyoid Neck dissection” which includes the removal of lymph nodes levels 1-3. Some routinely include level 4 for tongue carcinomas due to possibility of skip metastasis.

Primary lymphatic drainage of OROPHARYNX is upper cervial lymph nodes including:
Levels 2, 3, and 4 in addition to retropharyngeal and parapharyngeal nodes.

Question 44

Levels of the neck anatomy

Answer 44

Level 1a (submental lymph node group)
- superior is mandible
- bilaterally is anterior belly of digastric muscle
- inferiorly is hyoid bone
- mylohyoid forms floor

Level 1b (submandibular lymph node group)
- superior is mandible
- anterior is anterior belly of digastric
- posterior is stylohyoid/posterior belly of digastric
- inferiorly is hyoid bone
- mylohyoid and hypoglossus form floor

Level 2 (upper jugular lymphatic chain)
- superior is skull base
- anteriorly is sternohyoid muscle
- posterior is posterior border of sternocleidomastoid
- inferiorly is carotid bifurcation

Level 2a
- nodes anterior to spinal accessory nerve (CN 11)

Level 2b
- nodes posterior to CN 11

Level 3 (middle jugular lymphatic chain extending to carotid bifurcation)
- superior is carotid bifurcation
- inferior is omohyoid muscle
- at the level of lower border of cricoid cartilage
- anterior is sternohyoid
- posterior is posterior border of SCM

Level 4 (Lower jugular lymphatic chain)
- superior is omohyoid muscle
- inferior clavicle
- anterior by sternohyoid muscle
- posterior is SCM

Level 5 (posterior triangle of neck
- posterior border is SCM
- anterior border of trapezius muscle and clavicle
- cricoid cartilage

Level 6 (central compartment nodal group)
-bilaterally by carotid artery
-superiorly by hyoid bone
-inferiorly by sternal notch
-includes pretracheal, paratracheal, recurrent laryngeal, precricoid nodes
-Drains the thyroid gland, glottic and subglottic laryn, cervical esophagus, and apex of pyriform sinuses. Not included in neck dissection for oral cavity SCC

Question 45

SCC (high risks for cancer, premalignant lesions)

Answer 45

Tobacco (increases risk 5-9 fold)
Alcohol (increases risk 3-9 fold)
Tobacco and alcohol together increase chances 100x
Betel nut and other carcinogens
Immunosuppresion
Malnutrition
Excessive sun exposure of lips

Can develop SCC from premalignant lesions such as:
- Leukoplakia (white patch or plaque. remove and follow)
- Erythroplakia (red patch or plaque. remove with adequate margins due to higher malignancy potential than leukoplakia)
- Oral Lichen Planus (mucocutaneous disease characterized by T cell mediated degeneration of basal cell layer with low malignant potential. There is erosive and atrophic subtypes)
- Oral Submucous fibrosis (progressive fibrosis of submucosal layer and atrophy)

Question 46

Oropharyngeal SCC most commonly caused by what?

Answer 46

HPV more than 80% of oropharyngeal SCC, as opposed to 3-5% in oral cavity cancers

Question 47

Anatomic Stage/Prognostic Groups for SCC

Answer 47

-Stage 0: Tis N0 M0
-Stage 1: T1 N0 M0
-Stage 2: T2 N0 M0
-Stage 3: T3 N0 M0, T(1-3) N1 M0
-Stage 4a: T4a N(0-1) M0, T(1-4a) N2 M0
-Stage 4b: T4b AnyN M0
-Stage 4c: AnyT AnyN M1

Question 48

Indications for adjuvant radiation, complications with radiation

Answer 48

T3/T4 tumors
Positive or close (< 5 mm) resection margins
2 or more cervical lymph nodes containing metastatic cancer
Perineural or lymphovascular invasion
Extracapsular spread

Should be given within 6 weeks after surgery based on studies that showed poorer outcome with delayed treatment

radiation mucositis, dermatitis, tirmus, dysphagia, xerostomia, osteoradionecrosis, dental caries

Question 49

Chemotherapy indications for head and neck cancer

Answer 49

Positive resection margins
Extracapsular spread

Cisplatin is chemotherapeutic drug of choice. Commonly given weekly or every 3 weeks.

Cetuximab (monoclonal antibody targeting the EGFR) as alternative to those who cant use Cisplatin

Question 50

Management of the Neck for SCC (Oral cavity, Oropharynx)

Answer 50

Negative N0 with >20% chance of having occult regional metastasis (clinically and radiographically unidentifiable cancerous node due to small quantity of cancer cells present in the node) receive Selective Neck Dissection (SND)

Oral tongue SCC with depth invasion > 4 mm believed to have >20% chance of occult regional metastasis and warrants selective neck dissection for N0 neck. If lesion approaches within 1 cm of midline then bilateral neck dissection.
- Oral cavity SCC, SND involves removal of lymph node levels 1-3 and is called supraomohyoid neck dissection. Level 4 is often included for tongue carcinomas due to skip metastases

N0 oropharyngeal SCC requires removal of level 2-4 if surgery is selected as primary treatment.

Patient with nodal positive (N+) neck generally received removal of lymph nodes level 1-5.

Question 51

Types of comprehensive neck dissection

Answer 51

Radical neck dissection - includes levels 1-5 along with SCM, IJV and CN11. Reserved for N3 for extensive cervical involvement

Modified radical neck dissection - same as RND except preservation of one or more non-lymphatic structures (SCM, IJV, and/or CN 11) not invaded by cancer
MRND Type 1 - CN 11 preserved
MRND Type 2: CN 11, IJV preserved
MRND Type 3: CN 11, IJV, and SCM preserved

Extended neck dissection - RND and MRND and also removes carotid artery, hypoglossal nerve, or level 6 or 7 nodes. END reserved for cancer spread to these extended location

Question 52

Surgical Technique for a Neck Dissection

Answer 52

STANDARD UTILITY INCISION for exposure to level 1-4.
-Patient is placed supine on OR table with a shoulder roll to allow slight extension of the neck.
-Incision marked from mastoid process in a gentle curve over the mid-portion of the neck up to the contralateral submental region
-Infiltrate with local anesthetic with epi for hemostasis
-Incision with scalpel through skin and subq
-Bovie electrocautery to dissect through subq exposing platysma
-Platysma sharply divided with care taken to preserve clean edge for closure
-Subplatysmal flaps elevated superiorly until inferior border of mandible and inferiorly until the clavicle
- External jugular vein and greater auricular nerve are found coursing transversely over the SCM from inferior to superior, and during elevation of platysmal flap, structures preserved. Will encounter marginal mandibular branch of facial nerve
- Divide muscle over SCM and then retract muscle exposing levels 2,3,4
-CN11 identified and dissected from surrounding fascia to level of posterior belly of digastric
-CN 11 can be retracted and lymph node tissues from levels 2a and 2b can be dissected off over the splenius capitis muscle.
-Dissect inferiorly staying medial to transverse cervical nerves. Allows adequate dissection of level III lymph nodes off of the internal jugular vein
-Dissect lymph nodes off carotid artery, and retracted medially. Lymph nodes can then be dissected from levels 1A and 1B.
-Contralateral anterior belly of digastric, level 1A lymph nodes are dissected from mylohyoid muscle and digastric muscles. Care for submental branch of facial artery
-Dissect to level 1B, posterior edge of mylohyoid muscle is retracted anteriorly and sailvary gland is retracted out of submandibular fossa. Lingual nerve is identified along with submandibular ganglion and submandibular duct.
-Duct can be ligated and divided and gland dissected. Deep to digastric muscle is hypoglossal nerve and ranine veins. Care to not injure hypoglossal nerve or damage veins
-Lymph node specimen elevated from fascial attachment and oriented for pathological evaluation
-Close with 1-2 large suction drains and close platysma and then skin in separate layers.