Sinonasal lesions and masses Flashcards
List a broad differential for septal perforation
INFECTIOUS
1. Tuberculosis
2. Leprosy
3. Syphillis
4. Septal abscess
INFLAMMATORY
1. GPA
2. Sarcoidosis
3. SLE
4. Drug induced vasculitis
VASCULAR
1. Poorly controlled diabetes
2. Peripheral Vascular Disease
TRAUMA/IATROGENIC
1. Nasal trauma
2. Post septoplasty
3. Septal hematoma
4. Chronic nose-picking
5. Post nasal cautery
DRUGS
1. Chronic nasal decongestant use
2. Cocaine
NEOPLASTIC
1. Lymphoma
What is the difference between a mucous retention cyst vs. a mucocele of the sinus?
What is the cause of each?
Where are each most commonly found?
Mucous Retention Cyst (Pseudocyst):
- Retained mucous within a blocked goblet cell, lined by sinus mucosa rather than true epithelium - Mucous filled sac along a mucosal lining - PSEUDOCYST
- Secondary to obstruction of a mucous gland
- Common (10% of the population) usually asymptomatic
- Maxillary sinus MOST common
- Treatment not required unless obstructive
Mucocele (True cyst) :
- A TRUE cyst - chronic, cystic lesion of the paranasal sinuses lined with pseudostratified or low columnar epithelium, containing occasional goblet cells
- EXPANDING mucous containing epithelial lined cyst
- Due to obstruction of the sinus ostium causing obstructed drainage
- Results in secretion entrapment, bone resorption, and can be locally destructive
- Mucopyocele = infected mucocele
- Frontal (65%) > Ethmoid (25%) > Maxillary (10%) > Sphenoid (1%) - FEMS
- Radiologically presents with complete sinus opacifications, with rounded thinning pushing margins; blocked sinus
- Treated with FESS
DIFFERENT THAN MUCOUS RETENTION CYST/MUCOCELE OF SALIVARY GLAND
Kevan Page 29-30
What are the CT and MRI findings for Mucocele
- Hypointense on CT
- MRI Variable pattern, depends on hydration
1. Hyperintense on T1 (when dehydrated)
2. Hyperintense secretions on T2 with hypointense central area
3. T1 + Gad: Generally does NOT enhance, but if enhancing will do so at periphery
What is the most common sinonasal tumor?
Osteoma
What is the most common sinonasal tumor requiring intervention?
- Inverted papilloma (which is the second most common sinonasal tumor overall)
Discuss the differential for benign sinonasal tumors
A. EPITHELIAL TUMORS
1. Schneiderian Papillomas:
a/ Inverted
b/ Exophytic
c/ Oncocytic
2. Salivary gland adenoma
B. SOFT TISSUE TUMORS
1. Leiomyoma
2. Hemangioma
3. Schwannoma
4. Neurofibroma
C. BONE/CARTILAGE TUMORS
1. Chondroma
2. Osteoma
3. Chondroblastoma
4. Osteochondroma
5. Osteoid Osteoma
6. Osteoblastoma
7. Chondromyxoid fibroma
8. Sinonasal ameloblastoma
9. Chondromesenchymal hamartoma
10. Desmoplastic fibroma
Differential diagnosis for midline benign lesions 7
- Squamous papilloma
- Pleomorphic adenoma
- Hemangioma
- Angiofibroma
- Fibrous dysplasia
- Chondroma
- Osteoma
What are the 4 most common benign bony lesions/fibroosseous lesions of the sinonasal cavity?
- Osteoma
- Fibrous dysplasia
- Ossifying fibroma
- Osteochondroma
What are the 4 most common benign tumors of the sinonasal tract, in order of frequency?
- Osteoma
- Hemangioma
- Inverted papilloma/Papilloma
- Angiofibroma (JNA)
You see a unilateral mass in the nasal cavity. What should you NOT do?
- DO NOT BIOPSY
- May be an encephalocele or JNA
- Always image prior to biopsy
Regarding Antrochoanal polyp, discuss:
1. What is it?
2. Pathophysiology?
3. Features?
4. Treatment
ANTROCHOANAL POLYP:
- Inflammatory polyps (non-eosinophilic) arising from the mucosa of the maxillary sinus and extending through posterior accessory os to the nasal cavity or nasopharynx
Pathophysiology:
- Unclear
- Some suggest that these results from obstruction of natural os causing the polyp to enlarge and herniate through the posterior accessory os
Features:
- Almost always unilateral
- 4-6% of all polyps in general population
- 33% of all polyps in a pediatric population
Treatment:
- Endoscopic removal
Regarding sinonasal papillomas, discuss:
1. What are the risk factors 5
2. Clinical presentation?
3. What is the classification?
3. What is the staging?
4. Investigations?
4. What are the histopathologic findings?
5. What are the radiographic findings?
6. What are the treatment options?
Sinonasal papilloma
- Previously called Schneiderian papillomas
- Proliferation of squamous epithelium through finger-like projections into underlying stroma
RISK FACTORS:
1. M > F, Caucasian
2. Usually occurs around 5th to 7th decade of life
3. Organic solvents (carbon-based substances capable of dissolving or dispersing one or more other substances)
4. Smoking increases risk of recurrence and malignant transformation
5. HPV 6 & 11
6. EBV suspected (inhibit p53)
CLINICAL PRESENTATION:
1. Nasal obstruction (87%)
2. Rhinorrhea
3. Facial pain/pressure
4. Epistaxis
5. Frontal headaches
6. Epiphora
7. Exophytic, fleshy, sessile vs. pedunculated
8. Bony destruction/erosion common
9. Tendency to recur
CLASSIFICATION
1. Inverted Papilloma
- Most common - 50%
- 10% risk of malignant transformation
- Most commonly arises from the lateral nasal wall
- Recurrence rate 27-73%
- Exophytic Papilloma (aka. Fungiform)
- Second most common - 47% frequency
- 5% risk of malignant transformation
- Associated with HPV 6,11
- Most commonly arises from the septum
- Recurrence rate 22-50% - Oncocytic Papilloma (aka. Cylindrical)
- Third most common - 3%
- 15% risk of malignant transformation
- Most commonly arises from the lateral nasal wall (like IP)
- Recurrence rate 25-35%
INVESTIGATIONS:
1. Scope
2. CT: Look for osteitis sign (likely attachment/origin point)
3. MRI
4. Biopsy
KROUSE STAGING SYSTEM
1. T1: Confined to the nasal cavity without extension to the paranasal sinuses
2. T2: Extends to the medial maxillary wall, ethmoid sinuses, or osteometal complex
3. T3: Extends to any other wall of the maxillary sinus (superior, lateral, anterior, medial, inferior wall of the maxillary sinus), frontal sinus, or sphenoid sinus
4. T4: Extension beyond the paranasal sinuses, OR if final pathology is malignant (malignant transformation)
HISTOPATHOLOGIC FINDINGS:
- Hyperplastic ribbons of basement membrane enclosed with epithelium that grows downwards into the underlying stroma
- May have squamous metaplasia
- Exophytic - exophytic fronds with fibrovascular core
RADIOGRAPHIC FINDINGS
- MRI: Convoluted cerebriform pattern (“brain like” alternating roughly parallel lines of high and low signal intensity); Iso/Hypo T1; Enhance with Gad; Hypertense on T2
- Bony hyperostosis (enlargment) at the site of attachment on CT (“osteitis sign”)
TREAMTMENT:
1. Endoscopic Sinus Surgery for Total surgical removal
- Medial Maxillectomy (endoscopic Denker’s)
- TuNa-saving technique (modified medial maxillectomy that spares the inferior TUrbinate (tu) and the NAsolacrimal duct (na)
- Open en-bloc resection (e.g. lateral rhinotomy)
Kevan Page 39
Vancouver 428
Regarding inverted papillomas, discuss in greater detail:
1. Epidemiology
2. Common locations
3. Histology
4. Rate of malignant transformation & risk factors
5. Molecular characteristics
6. Treatment
7. Prognosis
INVERTED PAPILLOMA:
1. Second most frequent benign tumor of sinonasal tract after osteoma
2. Most common type of sinonasal papilloma
Epidemiology:
- 5-6th decade of life
Locations:
1. Most common: Lateral nasal wall
2. Maxillary sinus (maxillary medial wall
3. 30% involve multiple
4. Uncommon: Frontal/sphenoid
Histology:
1. Hyperplastic ribbons of basement membrane-enclosed epithelium that grow downward into underlying stroma
Malignant Transformation: 5-15%
- Usually SCC
- Rarely SNUC, Mucoep, Verrucous carcinoma
- Risk factors: Exposure to organic solvent (dose-response relationship)
- No association with smoke/alcohol
Molecular:
1. Characterized by EGFR mutation
Treatment: Endoscopic resection (dissect subperiosteal plane and drill underlying bone), but may be contraindicated it:
1. Concomitant presence of malignancy involving critical areas
2. Site of origin on anterior wall or lateral recess frontal sinus
3. Orbital involvement
Prognosis:
1. Post-op surveillance is clinical
2. Risk for recurrence: incomplete or inadequate resection, high staging, recurrent tumor, smoking
Regarding exophytic papilloma, discuss:
1. Epidemiology
2. Risk factors
3. Location
4. Treatment
Epidemiology:
- Second most frequent sinonasal papilloma
Risk factors:
1. HPV (6 and 11 - low risk) - therefore rare malignant transformation
Location:
- Predominantly anterior, inferior nasal septum
Treatment:
1. Surgical resection with wide margin - Subperichondrial/subperiosteal dissection
Regarding oncocytic papilloma, discuss:
1. Epidemiology
2. Location
3. Histology
4. Molecular
5. Malignant transformation
6. Treatment
Epidemiology:
1. Rarest form of papilloma
Location:
1. Lateral nasal wall
2. Maxillary sinus
Histology:
1. Abundant mitochondria in cytoplasm
2. Inverted and exophytic growth
Molecular: KRAS mutation (O-K)
Malignant transformation:
1. 4-17% (similar to IP)
2. No risk factors associated
Clinical and radiologic appearance, treatment follow up - same as IP
List a complete differential for an expansile/eroding sinonasal lesion.
NON-NEOPLASTIC
1. Invasive fungal sinusitis (CIFS, AIFS)
2. Allergic fungal sinusitis
3. Mucocele
4. Sarcoidosis
5. GPA
6. Cocaine
NEOPLASTIC - BENIGN
1. Inverted papilloma
2. Exophytic papilloma
3. Oncocytic papilloma
4. Juvenile Nasal Angiofibroma
5. Hemangioma
6. Hemangiopericytoma
7. Ossifying fibroma
NEOPLASTIC - MALIGNANT
1. Squamous cell carcinoma
2. Adenocarcinoma
3. Small round blue cell tumors (MR-SLEEP)
Small round blue cell tumors (MMR-SSLEEPPI):
1. Melanoma
2. Merkel Cell Carcinoma
3. Rhabdomyosarcoma
4. SNUC
5. Small cell neuroendocrine tumor
5. Lymphoma (e.g. NK)
6. Esthesioneuroblastoma
7. Ewing’s sarcoma / PNET
8. Primitive neuroectodermal tumor
9. Plasmacytoma
10. + Immature Teratoma
Child most common: Rhabdo, esthesio, Ewing, Lymphoma
Differential diagnosis for midline destructive or midline necrotizing lesions - 10
- GPA
- Idiopathic midline destructive disease
- Polyarteritis nodosa
- Foreign body granuloma
- Lymphoma
- Midline lethal granuloma (NK T-cell lymphoma)
- Cocaine Use (may also show palate necrosis)
- Iatrogenic (nose picking, septal cautery, etc.)
- Septal abscess
- Post op status
Regarding JNA, discuss:
1. What does it stand for?
2. What is the epidemiology? 3
3. Location? 1
3. What are the proposed theories of etiology? 5
4. What are the common symptoms? 11
5. How is it usually diagnosed?
6. Besides imaging, what other investigations should be done?
6. What are the classic findings on imaging?
7. What are the classic findings on histopathology?
JNA = Juvenile Nasal Angiofibroma
EPIDEMIOLOGY:
1. Adolescent boys (males, second decade, rare beyond 25yo)
2. Caucasian
3. May be associated with FAP (Familial adenomatous polyposis, e.g. Gardner Syndrome)
LOCATION:
- Centered at the PPF (superior border of the sphenopalatine foramen-basisphenoid)
- Usually extends into nasopharynx ± pterygomaxillary fissure (PMF), infratemporal fossa (ITF), skull base, or cavernous sinus and orbit
CAUSATIVE THEORIES:
1. Hormonal
2. Embryologic remnant of the first arch artery
3. Non-chromaffin paraganglionic cells (variant of paraganglioma or infantile hemangioma)
4. Arises from embryologic fibrocartilage between the basi-occiput and basi-sphenoid; OR periosteum of skull base
5. Genetic (deltion of chromosome 17)
SYMPTOMS:
1. Unilateral nasal obstruction
2. Recurrent epistaxis
3. Serous otitis media / CHL
4. Proptosis (exophthalmos)
5. Obstructive sleep apnea
6. Dacrocystitis
7. Rhinolalia (nasal tone in speech especially when caused by excessive closure or openness of the posterior nares)
8. Hard and soft palate deformity
9. Facial swelling
10. Cranial neuropathy
11. Massive hemorrhage
DIAGNOSIS
1. Do NOT biopsy
2. FNL will show a large friable mass
3. Diagnosis is by clinical picture and imaging
IMAGING FINDINGS:
1. Arises from pterygopalatine fossa
2. Holman-Miller sign: Anterior bowing of the posterior wall of the maxillary sinus due to a space occupying lesion in the PPF
- Can also spread through openings of the PPF
3. Hyper intense on T2. Enhances on T1. Flow voids
OTHER INVESTIGATIONS:
1. Angio with embolization prior to removal
2. Female: Karyotyping to rule out androgen insensitivity/testicular feminization
PATHOLOGY FINDINGS:
1. Multiple thin walled vessels lackign smooth muscle in a fibrous connective tissue stroma with abundant mast cells
2. Benign fibrovascular lesion composed of 2 components:
a/ Fibrous component = fibrous or collagenous stroma with fibroblasts and spindle/stellate cells (arising from myofibroblasts)
b/ Vascular space = network of irregularly shaped blood vessels (no muscular layer)
2. Stains positive for Vimentin on electron microscopy
Kevan Page 40
What is the staging system(s) for Juvenile Nasal Angiofibroma?
One to memorize: UFMC (staged after pre-operative embolization)
I - nasal cavity, medial PPF
II - Paranasal sinuses, lateral PPF, no residual vascularity
III - skull base erosion, orbit, ITF, no residual vascularity
IV - skull base erosion, orbit, ITF, residual vascularity
V - intracranial extension, residual vascularity, M = medial extension, L = lateral extension
Multiple staging systems - Radkowski classification is the most commonly used
RADKOWSKI CLASSIFICATION
STAGE 1: Nasal cavity/Sinuses
- 1A: limited to nasal cavity ± nasopharynx vault
- 1B: Involvement of at least 1 paranasal sinus
STAGE 2: PPF/ITF
- 2A: Minimal lateral extension into the PPF
- 2B: Full occupation of the PPF with or without erosion of orbital bones
- 2C: Extension into the ITF laterally with or without cheek, OR extension posteriorly through the pterygoid plates
STAGE 3: Skull base/intracranial
- 3A: Erosion of base of skull ± minimal intracranial extension
- 3B: Extensive intracranial extension ± cavernous sinus involvement
CHANDLER CLASSIFICATION
1. Stage 1: Confined to nasopharynx
2. Stage 2: Extends to nasal cavity ± sphenoid
3. Stage 3: Extends to maxillary sinus, ethmoid sinus, PPF, ITF, orbit, or cheek
4. Stage 4: Intracranial extension
SESSIONS 1981 CLASSIFICATION
1. Stage IA: Tumor limited to posterior nares and/or nasopharyngeal vault
2. Stage IB: Tumor involving posterior nares and/or nasopharyngeal vault with involvement of at least 1 paranasal sinus
3. Stage IIA: Minimal lateral extension into Pterygomaxillary fossa
4. Stage IIB: Full occupation of pterygomaxillary fossa with or without superior erosion of orbital bones
5. Stage IIC: ITF with or without cheek invasion
6. Stage III: Intracranial extension
FISCH CLASSIFICATION
1. I: Limited to nose and/or nasopharyngeal vault
2. II: Extension to one or more sinuses, or the PPF
3. III: Invades the ITF, orbit, or parasellar areas
4. IV: Extends into cavernous sinus, optic chiasm, or pituitary fossa
What are 8 routes of intracranial spread for JNA?
- Direct extension through foramen rotundum, ovale, spinosum, and lacerum
- Through the pterygomaxillary fissure to the infratemporal fossa to the middle cranial fossa
- From the pterygomaxillary fissure to the inferior orbital fissure to the orbital cavity to the superior orbital fissure (to the middle cranial fossa)
- Through the cribriform plate to the anterior cranial fossa
- Through the roof of the sphenoid sinus into the sella (medial to IC and cavernous sinus)
- From the nasopharynx and nasal cavity along the vidian nerve into the floor of the sphenoid sinus
- Anteriorly: Posterior wall of the maxillary sinus is progressively pushed forward
- Through the ethmoid sinuses superiorly to the anterior cranial fossa
What are the treatment options for JNA? 4
- Pre-operative embolization (24-72h prior to excision) - significantly decreases intraoperative blood loss and facilitated resection of larger tumors
- Surgery is the mainstay of therapy - recurrence 30-50% (but can spontaneously regress in some cases)
- XRT 30-35Gy is reserved for recurrence or larger/unresectable lesions with significant risks in a developing child
- Hormonal therapy: Flutamide (testosterone receptor blocker) or estrogen - decreases size and vascularity of tumor, but due to risks and variable response not used
What is the blood supply to a JNA?
External Carotid artery branches (in the majority of cases)
- Internal maxillary artery –> sphenopalatine branches
- Ascending pharyngeal branches
Internal Carotid artery branches (usually in larger tumors)
- Ophthalmic artery
- Ethmoid arteries
- Branches of the cavernous carotid (hypophseal and meningeal branches)
MAIN BLOOD SUPPLY:
1. Internal maxillary artery
2. Others: Ascending pharyngeal, vidian artery, unnamed branches from the internal carotid artery (Rare)
List the possible surgical approaches to a JNA, from least to most invasive
A. Last Invasive: Endoscopic Endonasal
B. Open Approaches
1. Anterior Intraoral
a/ With Degloving Approach
- ± LeFort 1 osteotomy
- Transantral approach
- Modified transantral approach with medial maxillectomy
- Maxillary/zygomatic removal then reinsertion (maxillary swing)
b/ Without Degloving Approach
- Transpalatal approaches
- Anterior Facial
- Weber-Ferguson approach
- Lateral Rhinotomy
- Medial maxillectomy - Lateral
- Fisch Type D trans-temporal approach
- Pre-auricular ITF approach
- Subcranial
Biopsy of which 4 nasal masses are at significant risk of hemorrhage?
- JNA
- Hemangioma
- Hemangiopericytoma
- AV malformations
What are the potential complications of radiotherapy for management of JNA? 4
- Failure of treatment
- Induction of malignancy - fibrosarcoma
- Failure of facial growth centers
- Cataract formation
Regarding sinonasal osteomas, discuss:
1. What is the most common presentation, and which sinus is most common?
2. What syndrome is it typically associated with? What other things come with this syndrome?
3. Describe the classification system of the types of osteomas
4. What are 3 proposed etiology theories?
5. What are the imaging features?
6. Histopathology?
7. What is the treatment?
Sinonasal osteomas are the MOST COMMON benign tumor of the sinonasal tract.
PRESENTATION:
- Frontoethmoidal (95%) > Frontal (80%) > Ethmoid (25%) > Maxillary (< 5%) > Sphenoid (FEMS, same distribution as mucocele)
- Males 3:1
- Painless slow growing mass, usually an asymptomatic finding
- Complications: Sinusitis (28%), Orbital, or intracranial
ASSOCIATED WITH: Gardner Syndrome
- Form of Familial adenomatous polyposis - autosomal dominant - 100% risk of colorectal cancer by age 40
- Skull osteomas
- Epidermoid cysts
- Fibromas
- Increased risk of papillary thyroid cancer
FU & PERZIN CLASSIFICATION
1. Eburnated osteoma (aka. Ivory/Compact osteoma)
- Lobulated
- Made of compact DENSE bone
- Minimal fibrous tissue
- No evidence of haversian ducts (series of tubes around narrow channels formed by lamellae)
2. Mature Osteoma (aka. Osteoma Spongiosum/cancellous)
- Spongy mature bone with bony trabeculae
- Contains fibrous tissue
3. Mixed Osteoma (Combination of features above)
ETIOLOGY: 3 PROPOSED THEORIES
1. Embryologic theory: Embryonic remnants arising from junction between the embryologic membranous frontal bone and endochondral ethmoid
2. Traumatic theory: Develops secondary to trauma (e.g. post-surgical, repetitive traction e.g. mandible)
3. Infective theory: Develops secondary to local inflammation (osteitis) resulting in osteogenesis
IMAGING FEATURES:
1. Localized bony mass on CT
2. Ivory/Eburnated = high density like cortical bone
3. Mature/spongiosum = ground glass appearance
HISTOPATHOLOGY:
1. Gross: Smooth and lobulated, sessile or pedunculated, covered by sinus mucosa
2. Fu & Perzin classification on types
Treatment: Removal only if symptomatic
Kevan page 42
https://img.freepik.com/premium-vector/specific-bone-part-haversian-duct-marrow-cavity-vector-illustration_33402-659.jpg?w=2000
Regarding Sinonasal Ossifying Fibroma, discuss:
1. What is the definition?
2. What are the subtypes?
3. What are the histological findings?
3. What are the imaging features on CT and MRI?
4. What is the treatment?
DEFINITION
Historically, ossifying fibroma and fibrous dysplasia were grouped together, but are now considered separate entities
- Ossifying Fibroma: True benign neoplasm, but can be aggressive and locally destructive
- Fibrous dysplasia: Genetic developmental anomaly
- Histologic differences are that fibrous dysplasia lacks a capsule and there is more immature bone without osteoblastic activity
SUBTYPES OF OSSIFYING FIBROMA (WHO 2017)
1. Odontogenic Origin
- Usually involves tooth bearing bone of mandible or less commonly maxilla
2. Juvenile Trabecular
- Usually involves alveolar process of maxilla
3. Juvenile Psammomatoid
- Usually arises from fronto-orbital and ethmoid bones
HISTOLOGY:
- Osteoid rimmed by osteoblasts forming lamellar bone “osteoblastic rimming”
IMAGING FEATURES
CT Findings:
- Eggshell-like rim: presence of a capsule (unlike fibrous dysplasia lacks a capsule), with central lucency
- Mixed density pattern
- Round or oval
MRI Findings:
- T2 Hyperintense
- T1 Iso or hyperintense in centre, hypointense in periphery
TREATMENT:
- Wide radical surgical resection - if not removed completely can recur rapidly
- High recurrence rate
- Malignant transofmration has never been described
Vancouver 427
Regarding fibrous dysplasia, discuss:
1. What is fibrous dysplasia?
2. What is the genetics?
2. How is it classified?
3. Clinical presentation
4. What are the imaging findings?
4. What are the histopathologic findings?
5. What is the treatment? 3
6. What is contraindicated in the disease with respect to treatment?
Fibrous dysplasia: Genetic abnormality of osteoblastic differentiation
- Results in replacement of normal medullary bone with immature fibro-osseous bone
- Genetic cause, non-familial
GENE:
- GNAS1 (20q13.2) - Post-zygotic missense mutation - NOT hereditary
CLASSIFICATION
1. MONOOSTOTIC (75-80%): Involves a single bone
- Note: multiple locations in the skull are still considered monoostotic (but technically be called craniofacial fibrous dysplasia)
- Usually manifests in second/third decade
- M=F
2. POLYOSTOTIC (20-25%): Involves multiple bones (typically femur and tibia)
- Can be associated with McCune-Albright Syndrome
- Craniofacial skeleton and femur are most frequently involved
- Occurs in first decade
- 3F > 1M
3. McCune-Albright Syndrome (< 1%) - 3P’s with 2/3 diagnostic:
- Polyostotic disease
- Hyperpigmentation (Cafe-au-lait)
- Precocious puberty & endocrinopathy-thyroid/parathyroid
- Typically occurs in 1st decade
4. Juvenile fibrous dysplasia
- Rapidly destructive and aggressive, refractory to treatment
CLINICAL PRESENTATION:
- Presents before age 30
- 25% occur in H/N - most common maxilla, but ethmoid, sphenoid, frontal, and temporal bones common affected too
- Lesions typically present as enlarging painless bony swelling, typically “burn out”
- Symptoms: sinusitis, proptosis, diplopia, compression of cranial nerves in foramina, facial pain, facial asymmetry, headache, and hearing loss
- Ostemyelitis can co-exist
IMAGING
1. Expanded osseous lesion with ground-glass appearance with areas of sclerosis - might look like pagetoid or sclerotic lesion
2. Egg-shell thin cortex
3. No rim (unlike ossifying fibroma)
4. CT: Featureless trabecular (ground-glass) pattern
5. MRI: Hypo to hyperintense on T1; T2 homogenous (like air)
6. Sinus involvement: calcified, thick, enlarged sinus margin and a ground-glass appearance of mass within the sinus
7. Differential - when located on sphenoid ridge, may be a meningioma
HISTOPATHOLOGY:
- “Chinese character-like” spicules of bone in fibrous stroma
- Marrow-space replaced by irregular spindle-shaped mesenchymal cells forming whorled patterns
- Poorly developed bony trabeculae with lack of osteoblastic rimming
- Lack of osteoblastic rimming (in which osteoblasts rim the fibroosseous tissue)
TREATMENT:
1. Unlike with ossifying fibroma (which is ride radical resection), goal here is to relieve symptoms
2. Observation if asymptomatic
3. Partial or radical resection if symptomatic with goal of symptom relief
4. Decompression of cranial nerves (usually optic, facial nerve, cochleovestibular) - only if symptomatic, should not do prophylactically due to risk of injury
5. Curettage for diplopia and sinus obstruction - reucrrence rate 20-30%
6. Radiotherapy is CONTRAINDICATED –> risk of osteosarcomatous degeneration (0.5% for Type 1-2, 5% Type 3, 50% if radiated) - can also impair facial skeleton growth
7. Medical: Consider steroids to temporize optic compression; bisphosphonates if bone pain (and deecreases risk of fractures)
Vancouver 427
What are two ways to differentiate fibrous dysplasia from ossifying fibroma?
- Ossifying fibroma has a capsule
- Fibrous dysplasia has more immature bone without osteoblastic activity
Regarding Hemangiopericytoma, discuss:
1. What is it?
2. What type of tissue is it predilected for?
2. How does it typically present? 2
2. What is the histopathology? 3
3. What is the treatment? 3
4. Prognosis
What is it?
- Vascular tumor, formed by the proliferation of pericytes of Zimmerman (wrap around vessels with occasional spaces instead of a whole smooth muscle)
- A vessel wrapped by a continuous layer of adjacent smooth muscle cells is an arteriole, where a pericyte is if there is only an occasional spatially isolated contractile cell on a vessel
- Occurs wherever there are capillaries; MSK & skin predilection
Presentation
- Can be benign or malignant
- Determined clinically, not histologically
- No reliable histopathologic features to differentiate (similar to paragangliomas)
- Unpredictable, and can be considered malignant and infiltrated
HISTOPATHOLOGY
- Staghorn Vessels: Thin-walled, branching vessels displaying perivascular hyalinization
- Nuclei are oval or spindle shaped; Staghorn shaped capillary spaces lined by lump pericytes
- Packed ovoid/spindle cells
TREATMENT:
1. Open or endoscopic wide surgical resection
- Complete resection is most important factor determining recurrence rate
- May require pre-operative embolization
- Neck dissection NOT necessary as lymphatic spread is rare
- XRT
- Generally for palliative cases
- Option for adjuvant XRT if incomplete resection/positive margins or high grade features
PROGNOSIS:
- 5-year survival rate near 70%
- Distant metastases usually suggest recurrence at the primary site
Vancouver 431
Regarding lobular capillary hemangioma (aka. Pyogenic Granuloma), discuss:
1. What is it?
2. Where do they most commonly occur in the head/neck?
3. What is the etiology? 2
4. How is it treated?
Commonly referred to as a PYOGENIC GRANULOMA
- Currently considered a misnomer as not associated with infection and not a true granuloma either
-Vascular tumor caused by proliferation of capillaries arranged in lobules
- Often infiltrated by inflammatory cells
- In H/N, most occur in oral cavity
- Only 10% in nasal cavity
ETIOLOGY:
1. Often presents in women during pregnancy (hormonal factors)
2. Can also present following trauma (e.g. nose picking, nasal packing)
TREATMENT:
1. Excision with submucosal dissection
Regarding plasmacytoma, discuss:
1. What is it?
2. Types? 3
3. Treatment?
4. What should you differentiate this from, and how do you do so?
PLASMACYTOMA:
- Plasma cell dyscrasia where tumor grows within soft tissue or axial skeleton
TYPES:
1. Solitary plasmacytoma of bone (SPB): Most common, 85% in the upper respiratory tract
2. Extramedullary plasmacytoma (EP)
3. Multiple plasmacytomas
TREATMENT:
1. Radiotherapy
2. Surgery for solitary or obstructive lesions
ASSOCIATION: MULTIPLE MYELOMA
- Must differentiate from multiple myeloma
- Skeletal forms frequently progress to multiple myeloma over 2-4 years
- Multiple Myeloma = CRAB (hypercalcemia, renal dysfx, anemia, multiple bone lesions)
- Plasmacytoma = Normal bone marrow (< 5% plasma cells), normal skeletal survey, absent or low paraprotein (SPEP) and no end organ damage
List a full differential of sinonasal cavity cysts
Sinonasal cavity cysts can be congenital or acquired, midline or lateral
CONGENITAL
A/ MIDLINE
1. Rathke’s cleft cyst
2. Thornwaldt Cyst - remnant of embryologic notochord (bright on both T1 and T2)
3. Dermoid cyst
B/ LATERAL
1. Branchial cyst (aka. Branchiogenic cyst)
ACQUIRED
A/ MIDLINE
1. Mucous retention cyst
2. Intra-adenoid cyst
3. Infectious cyst
B/ LATERAL
1. Oncocytic cyst (e.g. Warthin’s)
2. Mucous retention cyst
3. Intra-adenoid cyst
4. Infectious cyst
What are the 2 most common sinonasal carcinomas?
- Squamous cell carcinoma
- Adenocarcinoma
What are the subtypes of sinonasal adenocarcinomas? 7
- INTESTINAL TYPES
Barnes Classification:
a. Papillary
b. Colonic
c. Solid
d. Mucinous
e. Mixed - NON-INTESTINAL TYPES
a. High grade
b. Low grade
What is the most common salivary malignancy of the sinonasal tract?
Adenoid cystic carcinoma
Mass in the nasopharynx, on histology is cytokeratin negative, LCA positive. What is LCA and what is the lesion?
LCA = Leukocyte common antigen - marker for leukocytes
Cytokeratin is an epithelial marker
This would be consistent with lymphoma (SCC/NPC is ruled out because of negative cytokeratin)
What is the Kadish staging system for olfactory neuroblastoma
- Stage A: Tumor confined to the nasal cavity
- Stage B: Tumor in nasal cavity extending to paranasal sinus
- Stage C: Tumor extending to orbit, base of skull, cranial cavity or with cervical/distant metastasis
What is the UCLA staging systems for Olfactory neuroblastoma?
T1: Tumor involving the nasal cavity and/or paranasal sinuses (excluding sphenoid), sparing the most superior ethmoidal air cells
T2: Tumor involving the nasal cavity and/or paranasal sinuses (including the sphenoid) with extension to or erosion of the cribriform plate
T3: Tumor extending into the orbit or protruding into the anterior cranial fossa
T4: Tumor involving the brain
What is Tornwaldt’s cyst
What is its embryogenesis
What are the signal characteristics on MRI?
- Developmental benign cyst in the midline within the nasopharynx
- Embryogenesis: Forms as a result of a potential space developing in the nasopharynx. Point where the notochord retains its union with the pharyngeal ectoderm resulting in the outpouching of ectoderm into the pharyngobasilar fascia
- Ciliated respiratory epithelium
- Filled with jelly-like material
- thorNwaldts = remnant of the Notochord
- MRI is the investigation of choice. The presence of protein and/or associated hemorrhage within the cyst leads to high signal intensity on both T1- and T2-weighted images.
Vancouver 433
Regarding silent sinus syndrome, discuss:
1. Criteria for silent sinus syndrome 3
2. Pathogenesis
3. Differential
CRITERIA:
1. Spontaneous change in appearance of the eye (midfacial deformity)
2. Presence of ipsilateral enopthalmos and hypoglobus
3. Radiographic findings, including maxillary sinus atelectasis with complete or partial opacification of the affected sinus
Pathogenesis: Unclear, thought to result from sinus outflow obstruction, negative pressure and atelectasis.. precipitating event
Differential:
1. Maxillary sinus hypoplasia
- Congenital; often associated with hypoplastic or absent uncinate process
- ?Common after prior Caldwell-Luc
What is the difference between silent sinus syndrome vs. Maxillary hypoplasia?
Describe the classification (name and system) of maxillary sinus hypoplasia.
Maxillary Hypoplasia = CONGENITAL lack of development of the maxillary sinus. no enopthalmos
Silent Sinus Syndrome = ACQUIRED negative pressure in the maxillary sinus due to poor drainage, results in enopthalmos. On CT silent sinus looks like the whole lateral wall is being sucked in, including turbinate.
BOLGER CLASSIFICATION OF MAXILLARY SINUS HYPOPLASIA
1. Type 1:
- Small maxillary sinus
- Normal uncinate process
- Patent infundibular tract
- Type 2:
- Aplasic or hypoplastic uncinate
- Infundibular tract ill defined or absent
- Marked hypoplasia and opacification of the maxillary sinus - Type 3:
- Absent uncinate process
- Maxillary sinus is only represented by a cleft in the lateral nasal wall
Kevan Page 50
What are 13 granulomatous diseases of the sinonasal tract?
Alternative question: Differential for a patient with smelly crusts and open nasal cavity
A. FUNGAL
1. Sporotrichosis (Sporothrix Schenckii)
2. Blastomycosis
3. Coccidiomycosis
4. Rhinosporidiosis (Rhinosporidium Seeberi)
B. BACTERIAL
1. TB
2. Leprosy (Mycobacterium Leprae)
3. Rhinoscleroma (Klebsiella Rhinoscleromatis)
4. Syphillis (Treponema Pallidum)
C. SYSTEMIC
1. Granulomatosis with Polyangitis
2. Eosinophilic granulomatosis with polyangitis
3. Sarcoidosis
4. Histiocytosis X
5. NK T-cell lymphoma
D. Non-granulomatous Crusts
1. INCS
2. Cocaine
3. Decongestants
Discuss Rhinoscleroma:
1. What is it?
2. What are the risk factors?
3. What is the common causative organism?
4. What are the stages?
5. How is it diagnosed?
6. What are the classic pathology findings? 3
7. What is the treatment?
What is it?
- Chronic Granulomatous infection of the nasal mucosa, paranasal sinuses, and respiratory tract
- Aka “Balkan leprosy”
Risk Factors:
1. Middle east
2. Latin america
3. Eastern europe
Organism:
- Klebsiella Rhinoscleromatis (Gram negative bacteria) - transmitted sexually or vertically
STAGES:
1. Catarrhal (some also call this atrophic)
- Foul smelling, Purulent rhinorrhea for weeks/months (“honey-coloured rhinorrhea”)
- Mucosal crusting
2. Atrophic
- Large foul crusts/plaques simulating atrophic rhinitis
- Some sources say the Catarrhal and Atrophic stage are the same
3. Granulomatous (aka. hypertrophic)
- Nasal mucosal granuloma and hyperplasia with bleeding (epistaxis) and cartilage destruction
- Large granulomas of the upper respiratory tract, uvula hypertrophy
- Hebra nose deformity
4. Fibrotic (aka. sclerotic)
- Nasal, laryngeal, tracheobronchial tree stenosis
- Rare to affect the larynx, most common stenosis of the nares and Nasopharynx
Diagnosis:
- Classic honey-comb color crusting in the nasal cavity
- History of travel to endemic countries
- Positive tissue culture (only 50%)
- May result in Hebra (marine snail) nose deformity
- Biopsy confirmation
Histology/Pathology (especially during granulomatous phase):
1. Mikulicz Cells = histiocytes with foamy cytoplasm (vacuolated, contains klebsiella)
2. Brown-Brenn or silver stain may be used to see bacteria
3. Russell bodies = eosinophilic bodies in cytoplasm (looks like pink specs/circles in cytoplasm)
4. Warthin Starry stain positive
- Pathology during catarrhal and atrophic phases: Mucosal inflammation, granulation tissue, neutrophilic infiltration, squamous metaplasia
- Pathology during Sclerotic/fibrotic phase = fibrosis, scleroma
Treatment:
1. Long term tetracyclines/Streptomycin OR ciprofloxacin (500mg BID x 3 months)
2. Debridement
3. Surgery if there is a laryngeal obstruction at the fibrotic stage
Kevan Page 8
Vancouver Notes Page 15
Kevan Gen #99
Discuss Rhinosporidium:
1. What is it and how is it transmitted?
2. What bug is it caused by?
3. What does it affect
2. What are the risk factors?
3. What are the features of the disease?
4. How is it diagnosed and what is seen on pathology?
5. How is it treated?
What is it?
- Chronic granulomatous infectiion of the mucous membranes
- Usually transmitted via traumatic inoculation
- Affects the mucosal epithelium
Cause:
- Water parasite Rhinosporidium Seebri
Risk factors:
- Endemic to South America, Africa, Southern India, Sri Lanka
Features:
1. Strawberry Lesions - pink lesions with whitish specks which are the chitinous walls (aminopolysaccharide) of the Rhinosporidium
2. Develops large, hyperplastic vascular friable bleeding nasal polypoidal masses (looks like a strawberry)
3. Friable vascular polyps can also involve conjunctive, oropharynx, nasopharynx, maxillary antrum, larynx, EAC, and parotid duct
Diagnosis:
1. Biopsy showing Sporangia (spores)
- Can be seen with typical fungal stains, including (1) Gomori Methenamine silver (GMS) = Grocott, or (2) Periodic Acid-Schiff (PAS)
Treatment:
1. Local surgical excision
2. Dapsone cream if recalcitrant (antibiotic, combined with rifampicin and clofazimine to treat leprosy)
Vancouver 425
What are the common nasal findings from cocaine use?
- Midline granuloma - septum, nasopharynx, soft palate
- Septal perforation
- Secondary infection - Staphylococcus aureus
“SMS” text me when he’s discharged
Regarding midline lethal granuloma (NK T-cell lymphoma), discuss:
1. What is it?
2. Associations?
3. Histology?
4. Treatment?
5. Survival?
Midline lethal granuloma:
- Lymphomatoid granulomatosis
- Extranodal tissue seen in lung, skin, kidney (as opposed to lymphom)
- 12% degenerate to lymphoma
Associations:
1. EBV
2. Asian heritage
Histology:
1. Angiocentric and invasive
2. Atypical polymorphonuclear neutrophils
3. No granuloma
Treatment:
1. XRT if localized
2. Cyclophosphamide and steroid if multifocal
Survival: 50%
What is the classic histology of idiopathic midline destructive disease? 3
- Typical polymorphonuclear neutrophils
- No vasculitis
- No granuloma
Differs from GPA and midline lethal granuloma
What is a nasal foreign body granuloma usually associated with? 2
What is the histology? 2
Associations:
1. Cocaine use
2. Intramucosal steroids
Histology:
1. Multinucleated giant cells
2. Foreign body material
What are four histologic and clinical differences of T-cell lymphoma and GPA of the nose?
- GPA has diffuse nasal ulcerations; Lymphoma lesions are focal, localized, and explosive
- GPA has small and medium vessel vasculitis; Lymphoma has a polymorphic lymphoid infiltrate with angiocentric & angioinvasive features
- GPA has an inflammatory cell infiltrate, histiocytes, and multinucleated giant cells; Lymphoma has a primarily lymphocytic infiltrate
- Otologic, tracheal, and renal involvement are rare in lymphoma
What are the imaging findings of osteogenic sarcoma and chondrosarcoma? 3
- Popcorn calcifications
- Sunburst pattern
- New periosteal bone formation
What are the limits of endoscopic resection of sinonasal tumors? 8
- Frontal sinus extension (massive)
- Nasal pyramid extension
- Lacrimal tract extension
- Intraorbital extension
- Massive skull base erosion
- Dural/intradural extension
- Hard palate extension
- Nasopharyngeal extension (beyond pharyngobuccal fascia)
What are the contraindications to exclusive endoscopic technique in sinonasal benign tumors? 4
Nicolai & Castelnuovo:
1. Massive involvement of the frontal sinus and/or of the supraorbital cell (mid-pupillary line)
2. Intradural extension or orbital extension
3. Concomitant presence of a malignancy involving critical areas
4. Presence of abundant scar tissue from previous surgery
FOMP’D
Frontal massive involvement / supraorbital cell
Orbital extension
Malignancy involving critical areas
Previous surgery/abundant scar tissue
Dural / intracranial invasion
What are the benefits and limitations of MRI for sinonasal pathology? 4 and 3
ADVANTAGES:
1. Differentiation of soft tissue involvement
2. Differentiation of soft tissue from fluids
3. Multiplanar capabilities with minimal patient movement
4. No exposure to radiation
DISADVANTAGES:
1. Poor visualization of bony involvement
2. Increased cost compared to CT scan
3. Liimitations due to metal
List 5 types of nasopharyngeal cysts.
What would be the differential diagnosis for these?
What are their associations?
- Rathke’s pouch cyst
- Thornwaldt’s cyst
- Dermoid Cyst
- Intraadenoidal cyst
- Extraadenoidal cyst
- Branchial cleft cyst
Differential diagnosis:
- Glioma
- Encephalocele
- Hemangioma
- Teratoma
Associations:
- Craniofacial deformities - hemicrania, anencephaly, palatal fissure
Discuss Rathke’s pouch cyst:
1. What is it?
2. Epithelium type?
3. Appearance on MRI?
RATHKE’S POUCH CYST:
- Remnant of invaginated ectoderm of the anterior pituitary gland
- Anterior to the pars intermedia
- High in nasopharynx near sphenovomeral junction
Epithelium: Ciliated respiratory epithelium
MRI: Variable depending on cyst composition (mucoid vs. serous)
- T1: Hyperintense if high protein content, or hypointense
- T2: Mostly hyperintense (70%) but can be hypo
- Gad: Usually no contrast of cyst is seen, but a thin enhancing rim of surrounding compressed pituitary tissue may be apparent
Vancouver 432
Discuss Thornwaldt’s cyst:
1. What is it and where is it located?
2. Epithelium type?
3. Imaging finding?
THORNWALDT’S CYST:
- Remnant of the notochord (long, rod-like midline structure that develops dorsal to the gut tube and ventral to the neural tube)
- Inferior to Rathke’s pouch
- Filled with jelly-like material
Epithelium: Ciliated respiratory epithelium
Imaging:
1. MRI: High signal intensity on both T1 and T2
Vancouver 432
What is a dermoid cyst of the nasopharynx?
- Epithelial lining?
- MRI findings?
- Benign developmental cyst derived from ectoderm and mesoderm
Epithelium: Stratified squamous epithelium with adnexal structures
MRI: Hyper T1, Hypo T2
Where is an intra-adenoidal cyst vs. extra-adenoidal cyst formed in the nasopharynx?
INTRA-ADENOIDAL:
- From median pharyngeal recess of Rosenmuller, opens onto adenoid bed
EXTRA-ADENOIDAL:
- Deep within pharyngobasilar fascia, remnant of the pharyngeal bursa; usual findings are a cuff of granulation tissue rostral to the pharyngeal tubercle
