Oral Pathology Flashcards
1-52 - OP 1/2: Intro to Oral Cancers/White Lesions 53-61 - OP 3: Red Lesions 62-84 - OP4: Pigmented Lesions 85-118 - OP5: Ulcerated Lesions 119-157 - OP6: Oral Cancer 158-172 - OP7: Non-Cystic Dental inflam lesions 173-209 - OP8: Odontogenic Cysts 210-217 - OP9: Non Odontogenic Cysts 218-252 - OP10: Odontogenic Tumors 253-296 - OP11: Bone Pathology
What is Leukoplakia?
Leukoplakia is a white patch that develops in the mouth. The condition is usually painless but is closely linked to an increased risk of mouth cancer
What is Proliferative Verrucous Leukoplakia?
Proliferative verrucous Leukoplakia (PVL) is a rare type of oral Leukoplakia, where white patches that have a high risk of becoming cancerous develop inside the mouth. It mainly involves the lining inside of the cheeks (buccal mucosa) and tongue.
What are Fordyce spots?
Are ectopic sebaceous glands which tend to be seen on the lip and buccal mucosa, becoming more prominent as patient get older. This is an example of developmental white lesion. Fordyce spots are harmless and painless.
What is Leukoedema?
Leukoedema is a white or whitish-grey oedematous lesion of the buccal and labial oral mucosa. The lesions may be diffuse or patchy and are usually asymptomatic. Leukoedema may be confused with Leucoplakia.
What is white sponge naevus?
White sponge nevus is a hereditary autosomal dominant condition characterized by the formation of white patches of tissue called nevi (singular: nevus) that appear as thickened, velvety, sponge-like tissue. The nevi are most found on the moist lining of the mouth (oral mucosa), especially on the inside of the cheeks
What is pachyonychia congenita?
Pachyonychia congenita is a rare genetic disorder characterized mainly by hypertrophy of the nails and hyperkeratosis of the skin and mucosae.
What is Dyskeratosis congenita?
Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome that is characterized by lacey reticular hyperpigmentation of the skin, dystrophic nails, mucous membrane Leucoplakia and pancytopenia. Diagnosis may be delayed until clinical signs are apparent.
What is Oral lichen planus?
(LIE-kun PLAY-nus) is an ongoing (chronic) inflammatory condition that affects mucous membranes inside your mouth. Oral lichen planus may appear as white, lacy patches; red, swollen tissues; or open sores. These lesions may cause burning, pain or other discomfort.
What is the pathogenesis for lichen planus?
T cell-mediated immunological damage to the basal cells of epithelium.
What are basal cells?
Basal cells are found at the bottom of the epidermis — the outermost layer of skin. Basal cells produce new skin cells. As new skin cells are produced, they push older cells toward the skin’s surface, where the old cells die and are sloughed off
Oral lesions are typically found in what percentage of patients who suffer from skin lesions?
50%
If skin lesions are described as violaceous, what does that mean?
They are of a violet colour.
Which surface is the common site for lichen planus to develop?
Flexor surface of the wrist is the most common site, here skin lesions develop slowly and 85% resolve within 18 months.
In contrast oral LP runs a more chronic course, sometimes several years. Oral lesions are usually bilateral or unilateral?
Bilateral and often symmetrical.
Where is the mist common location for oral lichen planus?
Buccal mucosa
A spectrum of appearances may be observed, alone or in various combinations for oral lichen planus, what best describes reticular appearance?
characterized by a fine network or netlike structure
A spectrum of appearances may be observed, alone or in various combinations for oral lichen planus, what best describes atrophic appearance?
Diffuse red lesions resembling erythroplakia.
A spectrum of appearances may be observed, alone or in various combinations for oral lichen planus, what best describes papular appearance?
Small white papules that may coalesce (come together to form one mass)
A spectrum of appearances may be observed, alone or in various combinations for oral lichen planus, what best describes erosive appearance?
Extensive areas of shallow ulceration
A spectrum of appearances may be observed, alone or in various combinations for oral lichen planus, what best describes bullous appearance?
Development of subepithelial bullae (blisters)
This dense, band-like infiltrate (dark purple) of lymphocytes hugging epithelial/connective tissue junction is shown histopathological to which oral condition?
Lichen planus
The histopathological slide of lichen planus shows that the epithelial layer has undergone what?
Hyperkeratosis.
Histopathology of lichenoid inflammation- not exclusive to lichen planus!
Therefore, close correlation with clinical findings is very important
Features of lichenoid inflammation is also seen in.
- Lichenoid reaction to drugs/restorative materials
- Lupus erythematosus
- Graft-versus-host disease
- Lichenoid inflammation associated with dysplasia
Why is Lichen Planus an oral potentially malignant disorder (OMPD)?
Because they have the potential risk of developing into oral squamous cell carcinoma.
Treatment for symptomatic Lichen Planus includes steroids, how do steroids affect the body?
Steroids also reduce the activity of the immune system, which is the body’s natural defence against illness and infection. This can help treat autoimmune conditions, such as rheumatoid arthritis or lupus, which are caused by the immune system mistakenly attacking the body.
Which medication can cause oral lichen planus?
Systemic medications such as beta blockers, nonsteroidal anti-inflammatory drugs, anti-malarial, diuretics, oral hypoglycaemics, penicillamine, oral retroviral medications are reported to initiate or exacerbate oral lichen planus and oral lichenoid reaction.
What is lupus erythematosus?
Lupus is an autoimmune disorder which attacks healthy part of your body, including soft tissues.
Candidosis, syphilitic leukoplakia, oral hairy leukoplakia all causes oral white lesions, however they fall under which class of white lesions?
Infective.
What is candidiasis?
Candidiasis is a fungal infection caused by a yeast (a type of fungus) called Candida.
Some species of Candida can cause infection in people; the most common is Candida albicans.
Candida normally lives on skin and inside the body, such as the mouth, throat, gut, and vagina, without causing problems.
Candida can cause infections if it grows out of control or if it enters deep into the body. For example, it can cause infections in the bloodstream or internal organs like the kidney, heart, or brain.
Oral thrush is a fungal infection of the mouth. It is not contagious and is usually successfully treated with antifungal medication.
What is syphilitic leukoplakia?
This term refers to a white lesion associated with syphilis, specifically in the tertiary stage of the infection. It is not considered to be a type of idiopathic leukoplakia, since the causative agent Treponema pallidum is known
What is oral hairy leukoplakia?
Oral hairy leukoplakia is a condition triggered by the Epstein-Barr virus (EBV). It causes white patches on your tongue. Sometimes the patches happen in other parts of your mouth. The patches may look hairy. This is where the name comes from.
What is meant by idiopathic?
relating to or denoting any disease or condition which arises spontaneously or for which the cause is unknown.
What causes Leukoplakia, proliferative verrucous leukoplakia?
The cause is yet unknown, these conditions are known as idiopathic.
What is meant by neoplastic?
A neoplasm is an abnormal growth of cells, also known as a tumour. Neoplastic diseases are conditions that cause tumour growth.
Growth can be either benign (noncancerous) or malignant (cancerous). Benign tumours usually grow slowly and can’t spread to other tissues.
What is meant by dysplastic lesions?
A term used to describe the presence of abnormal cells within a tissue or organ. Dysplasia is not cancer, but it may sometimes become cancer. Dysplasia can be mild, moderate, or severe, depending on how abnormal the cells look under a microscope and how much of the tissue or organ is affected.
What are squamous cells?
Squamous cells: These are flat cells in the upper (outer) part of the epidermis, which are constantly shed as new one’s form.
What is squamous cell carcinoma?
Squamous cell carcinoma (SCC) of the skin is the second most common form of skin cancer, characterized by abnormal, accelerated growth of squamous cells.
What is meant by ill defined margins?
Ill definition of the margins of a lesion is a common, though nonspecific, characteristic that suggests a malignant process. Ill-defined margins are often due to superimposed normal breast tissues obscuring the margins of a lesion.
White sponge naevus usually appears bilaterally or unilaterally?
Bilaterally, can present anywhere in the oral mucosa but is typically seen in the buccal mucosa.
What other areas of the body can white sponge naevus affect?
Nose, oesophagus and anogenital region.
What is hyperparakeratosis?
Hyperkeratosis refers to thickening of your skin’s outer layer
What is acanthosis?
Acanthosis nigricans (AN) is a mucocutaneous disorder of unclear origin characterized by the presence of hyperpigmented papillary lesions on the skin and papillomatous lesions in the oral cavity.
What is histopathology?
Histopathology refers to the microscopic examination of tissue in order to study the manifestations of disease
What is atypia?
State of being not typical or normal, in medicine, atypia is an abnormality in cells in tissue.
What are parakeratinized cells?
parakeratinized epithelium + An epithelium that is characterized by incomplete keratinization of the cells in the stratum corneum. The cells are flattened and composed primarily of packed tonofilaments. However, the cells may retain remnants of nuclei and other organelles.
What is a prickle cell?
Also known as a spinous cell is an epidermal cell that, as a histological artifact, develops numerous intercellular bridges that give it a prickly appearance.
What is the lamina propria?
A type of connective tissue found under the thin layer of tissues covering a mucous membrane
What are the treatment options for white sponge naevus?
None required
This basket appearance marked by the blue circle is indicative in which hereditary oral condition?
White sponge naevus.
Roughened white patch at site of chronic trauma is indicative of frictional keratosis, what would you expect to see histopathological?
Hyperkeratosis and prominent scarring fibrosis within submucosa
What is squamous cell carcinoma?
Squamous cell carcinoma (SCC) of the skin is the second most common form of skin cancer, characterized by abnormal, accelerated growth of squamous cells.
How do you treat frictional keratosis?
Should resolve when source of friction removed
What is median rhomboid glossitis?
Median rhomboid glossitis (MRG) is defined as the central papillary atrophy of the tongue.
What is erythroplakia?
Erythroplakia means “red patch” and refers to a lesion with a reddish appearance that doesn’t have another obvious cause. They appear in the mouth or throat. They tend to be flat and have a velvety texture. They may have white spots on them. Some have a tendency to bleed easily.
There is no treatment for geographic tongue however patients are told to avoid which type of food?
Spicy/acidic
Can dysplastic lesions, squamous cell carcinoma present as a red patch?
Yes
Median rhomboid glossitis aetiology is uncertain, however in most cases it is associated with which type of infection candida.
Histopathological view would show the loss of what on the dorsum of the tongue?
Lingual papillae
What would you expect to see histopathologicaly of median rhomboid glossitis?
- Loss of lingual papillae
- Parakeratosis and acanthosis of the squamous epithelium
- Candidal hyphae in parakeratin and associated neutrophils
- Chronic inflammatory infiltrate in connective tissue
Treatments for median rhomboid glossitis includes antifungal medication, regardless of the success of the treatment, what part of the tongue cannot be fixed?
The lingual papillae on the dorsum of the tongue will not grow back.
Erythroplakia and speckled leukoplakias have high likelihood of malignant transformation of what percentage?
(50%)
What form of leukoplakia is this?
Speckled leukoplakia
What is meant by exogenous?
having an external cause or origin.
What is meant by endogenous?
having an internal cause or origin.
Oral pigmentation can arise from exogenous causing superficial staining of mucosa such as?
- Foods
- Drinks
- Tobacco
What is hyperplasia?
An increase in the number of cells in an organ or tissue. These cells appear normal under a microscope. They are not cancer, but may become cancer
What is black hairy tongue?
Black hairy tongue is caused by an overgrowth of dead skin cells, causing lengthening of the papillae, and staining from bacteria, yeast, food, tobacco or other substances in the mouth. Black hairy tongue is a temporary, harmless oral condition that gives the tongue a dark, furry appearance.
What is the aetiology of an amalgam tattoo?
Amalgam introduced into socket/mucosa during treatment, presents as asymptomatic blue/black lesion, which can be seen in radiographs.
Amalgam tattoo can be associated which layers of the soft tissues?
Associated with collagen, elastic fibres and basement membranes.
If an amalgam tattoo cannot be seen on a radiograph what is the process for a diagnosis?
May be excised to confirm diagnosis.
What is melanotic macule?
Oral melanotic macule is a non-cancerous (benign), dark spot found on the lips or inside the mouth. An oral melanotic macule found on the lip is sometimes called a labial melanotic macule.
What causes a melanotic macule?
Melanotic macules usually arise from three sources: an intraoral freckle, postinflammatory pigmentation, or disorders such as Addison’s disease, Peutz-Jeghers syndrome, or Laugier-Hunziker syndrome. Although the melanotic macule does not develop due to sun exposure, its origin is not conclusive.
What are pigmented nevi?
Pigmented nevi (moles) are growths on the skin that usually are flesh-coloured, brown or black. Moles can appear anywhere on the skin, alone or in groups. Moles occur when cells in the skin grow in a cluster instead of being spread throughout the skin
What is Peutz-Jeghers syndromes?
Peutz-Jeghers syndromes (PJS) is a genetic disorder. People with PJS develop polyps and dark-coloured spots that appear on various parts of the body and are at greater risk for some types of cancer. Include multiple pigmented lesions on skin/mucosa, lips, tongue, palate, buccal mucosa, intestinal polyposis.
What is smoker’s melanosis?
Smoker’s melanosis (see Right) is increased tissue pigmentation, or darkening, due to irritation from tobacco smoke. Typically, this pigmentation occurs on the gingiva (gums) of the upper and lower front teeth
What is melanotic neuroectodermal tumour of infancy?
Melanotic neuroectodermal tumour of infancy (MNTI) is a rapidly growing benign tumour arising from the neural crest cells. It typically affects infants and occurs in the head and neck region.
What is mucosal melanoma?
Mucosal melanoma (MM) is a rare melanoma subtype that originates from melanocytes within sun-protected mucous membranes. Compared with cutaneous melanoma (CM), MM has worse prognosis and lacks effective treatment options
Melanotic macules are benign legions caused by increased activity of melanocytes, these are most found where?
Buccal mucosa, palate and gingiva most common sites. They are frequently excised to confirm diagnosis and exclude melanoma.
Histologically what would you expect to see for a melanotic macule?
- Increased melanin pigment in basal keratinocytes – not increased number of melanocytes
- Melanin pigmentary incontinence in underlying connective tissue
Mucosal melanoma is a malignant neoplasm of what?
Melanocytes
What are melanocytes?
A cell in the skin and eyes that produces and contains the pigment called melanin.
How does mucosal melanoma present at first in terms of symptoms?
Presents as asymptomatic. May remain unnoticed until pain, ulceration, bleeding or a neck mass.
What is the prognosis of mucosal melanoma?
Prognosis is poor, as it is typically very advanced at presentation, very invasive and metastasise early. Biology of mucosal melanomas is different from skin melanomas.
What doe the term pleomorphic mean?
Occurring in various distinct forms. In terms of cells, having variation in the size and shape of cells or their nuclei.
What is the treatment option for mucosal melanoma?
Surgical resection is mainstay treatment along with adjuvant radiotherapy.
What is an Ulcer?
localized surface defect with loss of epithelium exposing underlying inflamed connective tissue
Ulcers are associated with haematological disease, GI disease, HIV, what are these types of diseases?
Systemic disease.
Ulcers are associated with lichen planus, discoid lupus erythematosus, immunobullous disease, what are these types of disease?
Dermatological disease
What type of ulcer is this?
Aphthous
What type of ulcer is this?
Traumatic
Why is it extremely important that cause for traumatic ulcer is identified?
If no apparent cause is found with what appears to be a traumatic ulcer, then further investigations is warranted.
What does this image show?
Ulcerated squamous cell carcinoma, this can easily be mistaken as traumatic ulcer, hence the urgency to determine the diagnosis.
Why is it difficult to differentiate between the types of ulcers?
A large proportion of ulcers will show non-specific features, ulceration with loss of surface epithelium, inflamed fibrinoid exudate and inflamed granulation tissue.
If a vesicle is a small blister, what is a bulla?
Bulla is a blister with a diameter greater than 10mm
A subset of lesions are known as immunobullous disorder, what is this?
These are autoimmune diseases on which autoantibodies against components of skin and mucosa produce blisters.
Disorders which result in vesicles/bullae can be classified histologically depending on the location of the bulla, which are?
- Intraepithelial
- Subepithelial
Intraepithelial bullae can be further classified in to two groups what are they?
- Non-acantholytic (death and rupture of cells) eg viral infection such as HSZ
- Acantholytic (desmosomal breakdown)
What does acantholysis mean?
Means loss of coherence between epidermal cells due to the breakdown of intracellular bridges.
What are the stages for a intraepithelial non-acantholytic bullae?
- Virus targets and replicates within epithelial cells
- Leads to cell lysis
- Groups of infected cells breakdown to form vesicles within the epithelium
- Infected cells infect nearby normal cells and an ulcer forms when the full thickness of the epithelium is involved and is destroyed
What is a bullae?
A bulla is a fluid sac or lesion that appears when fluid is trapped under a thin layer of your skin.
What is pemphigus?
Pemphigus is a disease that causes blistering of the skin and the inside of the mouth, nose, throat, eyes, and genitals.
What is pemphigus vulgaris?
Is a rare group of autoimmune diseases. It causes blisters on the skin and mucous membranes throughout the body.
Pemphigus vulgaris is most frequently found in which sex and affects which ages?
Most frequently found in females ages 40-60.
What are autoantibodies?
An antibody produced by an organism in response to a constituent of its own tissues.
What is the treatment for pemphigus vulgaris?
Steroids
Which studies is used in combination of routine histopathology to confirm diagnosis of pemphigus vulgaris?
Direct immunofluorescence (DIF) studies.
What type of specimen needs to be provided for Direct Immunofluorescence?
Fresh specimen
These are examples of what type of lesions?
- Pemphigoid
- Erythema multiforme
- Dermatitis herpetiformis
- Epidermolysis bullosa acquisita
Subepithelial
What is pemphigoid?
Bullous pemphigoid is a rare skin condition that mainly affects older people. It usually starts with an itchy, raised rash. As the condition develops, large blisters can form on the skin. It may last a few years and sometimes causes serious problems, but treatment can help manage the condition in most cases
What is erythema multiforme?
Erythema multiforme is a skin reaction that can be triggered by an infection or some medicines. It’s usually mild and goes away in a few weeks. There’s also a rare, severe form that can affect the mouth, genitals and eyes and can be life-threatening. This is known as erythema multiforme major
What is Dermatitis Herpetiformis?
Dermatitis herpetiformis (DH) is a chronic, intensely itchy, blistering skin manifestation of gluten-sensitive enteropathy, commonly known as celiac disease. DH is a rash that affects about 10 percent of people with celiac disease
What is Epidermolysis bullosa acquisita?
Epidermolysis bullosa acquisita (EBA) is an acquired form of EB with similar symptoms. Like EB, EBA causes the skin to blister easily. It can also affect the mouth, throat and digestive tract. But EBA isn’t inherited, and symptoms don’t usually appear until later life.
The following belong to a group of?
- Bullous Pemphigoid
- Mucous Membrane Pemphigoid
- Linear IgA disease
- Drug-induced Pemphigoid
Autoimmune diseases
Which of the pemphigoid diseases is the most common orally?
Mucus membrane pemphigoid. Oral mucosa almost always involved and usually first affected site. Gingiva, buccal mucosa, tongue, palate.
With mucous membrane pemphigoid the bullae tend to be relatively tough, why?
Bullae tend to be relatively tough as the ‘lid’ is full thickness epithelium. When they rupture tend to heal slowly with scarring. Ocular lesions can lead to blindness.
What is the treatment for mucous membrane pemphigoid?
Steroids
What type of specimen is required for DIF for mucous membrane pemphigoid?
Fresh specimen
How many variants of epidermolysis bullosa is there?
3 variants
- Simplex- intraepithelial, mutations in keratins 5/14
- Junctional- subepithelial, separation in lamina lucida, laminin mutations
- Dystrophic- subepithelial, separation beneath basal lamina, mutation in type VII collagen gene
What is the name of the blood bullosa that presents on the palate?
Angina bullosa haemorrhagica
What is the name of this oral cancer?
Oral Submucous Fibrosis
What is chronic hyperplastic candidiasis?
Chronic hyperplastic candidiasis (CHC), earlier known as candida leucoplakia, is a variant of oral candidiasis that classically presents as a white patch on the commissures of the oral mucosa, and it is mostly caused by Candida albicans.
What would you grade these histological slides for epithelial dysplasia?
What is this type of cancer?
Squamous cell carcinoma
Where do teeth develop from?
Odontogenic epithelium and neural crest derived ectomesenchyme, the dental lamina buds down from the ectoderm and becomes the enamel organ.
What are the 4 layers of the enamel organ during odontogenesis?
4 layers of the enamel organ-
1. Inner enamel epithelium (future ameloblasts)
2. Outer enamel epithelium
3. Stellate reticulum
4. Stratum intermedium
With the radicular cyst being a slow growing swelling, how would describe the radiolucent lesion seen at the apex?
Typically, well-circumscribed unilocular radiolucent lesion.
What is a lateral radicular cyst?
Radicular cyst arising from a lateral root canal branch of a non-vital tooth
What is a residual cyst?
residual cyst that persists after extraction of the associated non-vital tooth
60% of inflammatory collateral cysts are paradental cysts, what are their clinical features?
. Long-standing pericoronitis
* Associated with vital tooth
* Well-demarcated radiolucency
What are the clinical features of a, mandibular buccal bifurcation cyst?
- Often painless swelling
- Associated tooth usually tilted buccally with deep perio pocket
- Well-demarcated buccal radiolucency
Odontogenic keratocyst is seen where in a radiograph?
Angle of the mandible
What are the clinical features of dentigerous cyst?
- 2nd most common odontogenic cyst
- Encloses all or part of crown of unerupted tooth
- Attached to Amelocemental junction
- Impacted teeth or late to erupt; 3, 5, 8 s
- Mandible > Maxilla, 20-50yrs
- Symptom-free until significant swelling or if infected
- Ballooning expansion
- Well-circumscribed unilocular radiolucency associated with crown of unerupted tooth
What is an eruption cyst and what are the clinical features?
Eruption cyst = dentigerous cyst arising in extra-alveolar location, clinical features are:
* Typically seen in children
* Deciduous and permanent molars
* Presents as bluish swelling
What is an eruption cyst and what are the clinical features?
Eruption cyst = dentigerous cyst arising in extra-alveolar location, clinical features are:
* Typically seen in children
* Deciduous and permanent molars
* Presents as bluish swelling
what are the clinical features of a lateral periodontal cyst?
- Uncommon
- Arise adjacent to vital tooth
- Canine and premolar region of mandible
- Wide age range
- Usually symptom-free, incidental finding
- Well-circumscribed radiolucency in PDL
What is a botryoid odontogenic cyst?
- Very rare multicystic variant of lateral periodontal cyst
- Botryoid= ‘Bunch of grapes’- polycystic appearance
- Typically multilocular radiolucency
- Mandibular premolar =canine region
- Adult
- Can recur
What is a glandular odontogenic cyst?
- Very rare
- Anterior mandible
- Wide age range
- Multilocular radiolucency
- Strong tendency to recur
What is the treatment option for infant gingival cysts?
None usually disappear in a few weeks
What is the name of this cyst?
Gingival cyst of adult
what is the name of this cyst?
Calcifying odontogenic cyst, arising from dental lamina
Where do nasopalatine duct cysts originate from?
Originate from epithelium of nasopalatine duct in incisive canal
What are the clinical features of ameloblastoma?
Clinical features:
1. 2nd most common odontogenic tumour
2. 30-60 yrs
3. Usually posterior mandible
4. Swelling
5. Radiolucent lesion on imaging
6. Slow growing, locally aggressive
Histopathology you will see 2 types of patterns for ameloblastoma, what are they?
2 patterns
* follicular (islands of epithelial cells)
* plexiform (long strands of epithelial cells)
Set in fibrous stroma
What would you expect to see histopathology for adenomatoid odontogenic tumour?
- Odontogenic epithelium arranged in solid nodules or rosette-like structures
- Duct-like structures
- Eosinophilic amorphous material
- Minimal fibrous stroma
What are the features of odontoma, compound type?
- Most common odontogenic tumour
- Esp Anterior maxilla
- Lots of tooth-like structures on imaging
- Fibrous capsule enclosing many separate, small, tooth-like structures (denticles/ odontoids)
- Aetiology???
What are the features of odontoma, complex type?
- Commonly posterior mandible
- Radiopaque mass on imaging
- Consist of an irregular mass of hard and soft dental tissues, haphazard arrangement with no resemblance to a tooth and often forming a cauliflower-like mass
- Cementum is often very scant
What are the treatment of cementoblastoma?
- Complete excision and removal of tooth
- Commonly recur if incompletely excised
What are the features for Melanotic Neuroectodermal Tumour of Infancy?
- Very rare
- Most < 1 yr old
- M>F
- Locally aggressive, rapidly growing pigmented mass
- Most frequently anterior maxillary alveolus
What are the features of polyostotic fibrous dysplasia?
- Rare
- F>M
- Affects several bones
- Skin pigmentation and endocrine abnormalities also associated
- Albright’s syndrome comprises polyostotic fibrous dysplasia, skin pigmentation and sexual precocity
- Head + neck involved in ~50% of cases
What are the histological features of polyostotic fibrous dysplasia?
- Irregularly shaped slender trabeculae of woven (immature) bone lying in a very cellular fibrous tissue
- Fuses directly with normal bone at edges of lesion
- Lesions stabilise as skeleton matures.
What are the histological features of cherubism?
- Lesions consist mainly of cellular and vascular fibrous tissue containing varying numbers of multinucleate giant cells
- As activity decreases lesions become progressively more fibrous and numbers of giant cells decreases
What are the histological features of hyperparathyroidism?
Histologically it is impossible to distinguish ‘brown tumour’ of hyperparathyroidism from other giant-cell lesions of bone (central giant cell granuloma, aneurysmal bone cyst) therefore clinical, radiological and biochemical investigations required
What are the histological features of Paget’s disease? –
varies with phase
- Main features are irregular pattern of reversal lines, many osteoblasts and osteoclasts, fibrosis of marrow spaces and increased vascularity
- Destruction and new bone formation may alternate rapidly, marked histologically by haemotoxylin-staining reversal lines Their irregular pattern produces a ‘Mosaic’ appearance in the bone
- Early phase there is typically more resorption than osteoblastic activity
- Late stage bones are thick, cortex and medulla are obliterated and the whole bone is spongy in texture
