Category: Oral Pathology

HISTOPATHOLOGICAL FEATURES OF COMMON ODONTOGENIC CYSTS

Dr.S.P.SunanthaLeave a comment

DENTIGEROUS CYST

• The lining epithelium is derived from reduced enamel epithelium and hence appears as uniformly thin non-keratinized epithelium.

• The epithelium comprises of 2-3 layers of flattened cells and is characteristically devoid of rete ridges.

Connective tissue capsule is derived from dental follicle, consists of young fibroblasts widely separated by ground substance rich in mucopolysaccharide.

• Connective tissue capsule may show odontogenic epithelial remnants.

• Cystic lumen contains cystic fluid which is thin, watery or may be blood tinged.

ODONTOGENIC KERATOCYST

• Typically shows a thin friable wall which is often difficult to enucleate from the bone in one piece.

• Cystic lumen may contain a clear liquid that is similar to a transidase of serum or it may be filled with a cheesy material, that on microscopic examination consists of keratinaceous debris.

• Microscopically, thin fibrous wall is essentially derated of any inflammatory infiltrate.

• Epithelium may show infoldings into the connective tissue capsule and may be separated from capsule in some areas.

CALCIFYING ODONTOGENIC CYST

• The lining epithelium is of variable thickness commonly around 5-10 layers.

• Spinous cells are loosely arranged.

• Presence of Ghost cells.

• Ghost cells are degenerating cells that appear as void, eosinophilic cells with nucleus showing different stages of degeneration.

• These cells are seen in thickened areas of lining epithelium.

• Connective tissue capsule is often scanty and sometimes contain discrete islands of odontogenic cells.

RADICULAR CYST

• The epithelial lining of the radicular cyst is stratified squamous in type of variable thickness.

• Epithelium shows spongiogenesis and inflammatory cell infiltration.

• Epithelium may show arc-shaped structures called Rushton bodies.

• The surrounding connective tissue shows granulomatous reaction due to the presence of Cholesterol clefts.

Source: Maji Jose

Letterer – Siwe Disease

Dr. Kriti JainLeave a comment
  • Rare, acute aggressive disseminated proliferative lethal disease of Langerhans cells that affects infants <2 years old.
  • Accounts for 10% of cases of Langerhans cell histiocytosis

Clinical features:-

  • Initial manifestation often skin rash involving trunk, scalp & extremities.
  • Recurrent pyoderma – like lesions with crusting and scaling, vesicopustular and purpuric eruption; resembling seborrhoeic dermatitis.
  • Denuded skin may facilitate microbial invasion, leading to sepsis.
  • Persistent low grade spiking fever with malaise & irritability.
  • Splenomegaly, hepatomegaly & lymphadenopathy are early manifestations.
  • Nodular lesions in body flexures and intraoral haemorrhage.
  • Myelophthisic anemia , leukopenia and thrombocytopenia may also be seen.
  • Bone lesions are not common initially.
  • Diffuse involvement of skeletal system occurs later in the disease.
  • The uvea may be affected; orbital involvement is most unusual
  • The pustules are sterile and Tzanck smear of the vesicopustules shows pale histiocytes which can be used as a rapid screening test.

Oral manifestations:-

  • Ulcerative lesions, gingivitis, loose teeth, ectopic teeth also may be seen.
  • Parents frequently report precocious eruption of teeth, when in fact the gums are receding to expose immature dentition
  • Diffuse destruction of maxilla & mandible.
  • Some cases extreme rapid course of disease; oral involvement does not occur.

Histologic Features:-

1.Very similar to HSC; histiocytic proliferation with or without eosinophils.

2.These histiocytes do not contain significant amounts of cholesterol.

3.‘Foam cells’ not a feature.

Treatment & Prognosis:-

  • Extremely poor; Course of disease rapid & terminates fatally in short time.
  • Poor prognostic features include younger age; dissemination of lesions; involvement of lungs, liver, CNS and RE system; associated infection; anaemia, thrombocytopenia and purpura
  • Chemotherapy coupled with radiation to localised bony lesions and supportive measures are useful in treatment.
  • Thymic extracts have been successfully used to treat LS disease

References:-

Shafer’s 8th edition

HISTOPATHOLOGICAL FEATURES OF COMMON SALIVARY GLAND TUMOURS

Dr.S.P.Sunantha1 Comment

PLEOMORPHIC ADENOMA

• It is a well circumscribed tumour with complete or partial encapsulation with dense fibrous tissue.

• Epithelial components include proliferating ductal and myoepithelial cells forming ductal structures containing eosinophilic material.

• These cells also may form sheets, strands or islands.

• Ductal cells are cuboidal in shape with scanty cytoplasm.

WARTHIN TUMOUR

• Warthin tumour is made up of epithelial component and lymphoid component.

• Cystic formation, papillary projections are seen, showing germinal centres.

• The cyst are lined by papillary proliferation of bilayered oncocytic epithelium.

• The epithelial cells are abundant, finely granular, eosinophilic and are arranged in two layers.

• The inner luminal layer consists of tall columnar cells with centrally placed, palisaded and slightly hyper-chromatic nuclei.

• The outer luminal layer consists of cuboidal or polygonal cells with more vesicular nuclei.

MUCOEPIDERMOID CARCINOMA

• Microscopically, three types of cells are seen, dispersed in the connective tissue stroma.

• First type is Epidermoid cells which are squamous with distinct intercellular bridges, rarely with evidence of keratin formation.

• Second type is mucous secreting cells which are ovoid, filled with mucin and peripherally placed nucleus (clear cells)

• Intermediate cells are another type of cells, ovoid with darkly staining nucleus and scanty eosinophilic cytoplasm.

ADENOID CYSTIC CARCINOMA

• The tumour is composed of uniform cells resembling basal cells arranged in anastamosing whorls or duct like pattern.

• Some of these duct like areas contain mucoid material.

• This feature gives rise to the characteristic appearance described as “cribriform”, “honeycomb” or “swiss cheese” pattern.

• There may be areas where the cells are tubular or more solid

• The connective tissue components is often hyalinized and surrounding the tumour cells, forming a structural pattern of cylinders (ACC aka cylindroma).

Source: Maji Jose

HISTOPATHOLOGICAL FEATURES OF MAJOR EPITHELIAL LESIONS

Dr.S.P.SunanthaLeave a comment

SQUAMOUS PAPILLOMA

• Papilloma is characterized by finger-like projections lined by hyperplastic stratified squamous keratinized epithelium.

• Each finger like projection has a central thin connective tissue core carrying the blood vessels.

LEUKOPLAKIA

• Histopathologically, leukoplakia is characterized by Hyperkeratosis, Acanthosis and Dysplastic features.

• Dysplastic features include bulbous or drop shaped rete ridges, basal cell hyperplasia, loss of polarity of basal cells, irregular epithelial stratification, cellular pleomorphism, alteration in nuclear cytoplasmic ratio, nuclear hyper chromatism and increased mitosis.

ORAL SUBMUCOUS FIBROSIS

• The epithelium is atrophic with short or flat rete ridges.

• Connective tissue shows juxta epithelial hyalinization and exhibits fibrosis with dense bundles of collagen fibres.

• Focal collections of chronic inflammatory cells are present.

• In severe cases, muscles undergo degenerative changes.

SQUAMOUS CELL CARCINOMA

• The most significant microscopic feature of squamous cell carcinoma is dysplastic epithelial cells invading connective tissue.

• These cells may be arranged in the form of cords, sheets or islands.

• Dysplastic features seen are hyperchromatism of nuclei, alteration of nuclear cytoplasmic ratio, pleomorphism of cells and nuclei, prominent nucleoli, many normal and abnormal mitotic figures, individual cell keratinization and keratin pearl formation.

Source: Maji Jose

Hand Schuller Christian Disease (Multifocal Eosinophilic Granuloma)

Dr. Kriti JainLeave a comment
  • Characterized by widespread skeletal & extra – skeletal lesions & chronic clinical course.
  • Occurs primarily in early life, before the age of 5; more common in boys & girls.
  • Most cases reported from Western literature, authentic cases from India are few.

Clinical features:-

  • Classic triad of :-
  1. Single or multiple areas of ‘punched out’ bone destruction in skull
  2. Unilateral or bilateral exophthalmos
  3. Diabetes insipidus with or without other manifestations of dyspituitarism
  • Involvement of facial bones frequently associated with soft tissue swelling & tenderness; causes facial symmetry.
  • Classically involves the flat bones of the skull, ribs, pelvis, and scapula
  • Diabetes insipidus affects 5 to 50% of patients.
  • Skin involvement in the form of erythematous scaly rash or papular or nodular lesions which is seen in only 30% of patients.
  • Poor sexual development and retarted growth is another feature.
  • Vision loss or strabismus caused by optic nerve or orbital muscle involvement occurs rarely.
  • Chronic otitis media and otitis externa due to involvement of the mastoid and petrous portions of the temporal bone with partial obstruction of the auditory canal are fairly common

Oral manifestations:-

  • Earliest signs of the disease; may be present in 5 – 75% of cases.
  • Often non specific; sore mouth, halitosis, gingivitis, ulcerations, loose teeth, suppuration, failure of healing of extraction sockets
  • Loss of supporting alveolar bone mimicking advanced periodontal disease is characteristic.

Radiological features:-

  • Skull lesions sharply outlined; jaw lesions may be diffuse.
  • Jaw lesions manifested as bone destruction with tooth displacement.
  • Panoramic may show remarkable atrophy of the alveolar ridge and severe parodontitis.
  • Remaining teeth abnormally sited in an extra alveolar position

 

Histological features:-

  • Manifesting in four stages during progression of characteristic lesion
  • Proliferative histiocytic phase with accumulation of collections of eosinophilic leukocytes scattered throughout sheets of histiocytes.
  • Vascular – granulomatous phase with persistence of histiocytes & eosinophils, sometimes with aggregation of lipid laden (cholesterol) macrophages.
  • Diffuse xanthomatous phase with abundance of ‘foam cells’
  • Fibrous healing phase.
  • Infiltration with CD1 positive histiocytes disclosing intracytoplasmic Birbek granules at the electron microscopic examination .
  • Histological diagnosis is based on the presence of a histiocytic infiltrate in the upper and middle dermis.
  • The optical microscope examination reveals in the papillary dermis an important oedema, large cells with an indented nucleus and abundant eosinophilic cytoplasm
  • Histochemical colouring, showing positiveness for S-100 protein, the presence of CD1, CD4 and HLA-DR surface antigens confirm the diagnosis

Treatment & prognosis:-

  • Therapy of the Hand-Schuller-Christian disease varies according to the age of the patient, the severity and extent of the clinical picture.
  • Approximately half of the patients undergo spontaneous remission over a period of years.
  • Treatment of choice is curettage or excision of lesions.
  • Inaccessible lesions may be irradiated.
  • Some patients may benefit from chemo – therapeutic drugs like Prednisone, Vinblastine & Cyclophosphamide.

Reference:

1.Faculty notes

2.Google

Tay – Sachs Disease

Dr. Kriti JainLeave a comment
Tay-Sachs disease
  • Characterized by mutation in or deficiency of enzyme hexosaminidase.
  • Without this, gangliosides, particularly ganglioside GM2, build up in cells, especially nerve cells in the brain.
  • Classified into infantile, juvenile, and adult forms, depending on the symptoms and when they first appear.
  • Most people with Tay-Sachs have the infantile form.

Clinical Features:-

  • Infants with this disorder typically appear normal until the age of 3 to 6 months
  • Affected infants lose motor skills such as turning over, sitting, and crawling.
  • Develop an exaggerated startle reaction to loud noises.
  • As the disease progresses, children experience seizures, vision and hearing loss, intellectual disability, and paralysis.
  • An eye abnormality called a cherry-red spot, is characteristic of this disorder.
  • Children with this severe infantile form of Tay-Sachs disease usually live only into early childhood.
Tay sachs DISEASE

References:-

1.Shafers’ 8th edition

2.Google images

3. For better understanding: https://youtu.be/2z3nSnBe8Vg

Niemann – Pick Disease

Dr. Kriti JainLeave a comment
  1. Autosomal recessive trait; due to lysosomal accumulation of sphingomylin resulting from inherited deficiency of sphingomyelinase.
  2. The accumulations take place in spleen, liver, lungs, bone marrow, and brain.
  3. A missense mutation causes complete deficiency of sphingomyelinase.
  4. The enzyme deficiency block degradation of lipid, resulting in the accumulation of sphingomyelin within lysosomes in the macrophage-monocyte phagocyte system.
  • The following 6 types of Niemann-Pick disease have been described:- 
  1. Type A – Acute neuronopathic form
  2. Type B – Visceral form
  3. Type C – Chronic neuronopathic form
  4. Type D – Nova Scotia variant
  5. Type E – Adult form
  6. Type F – Sea-blue histiocyte disease
  • Another classification divides this disease into –
  1. Type A – acute infantile form.
  2. Type B – less common, chronic, non – neurological form.
  3. Type C – biochemically & genetically distinct form

Clinical Features:-

  • Niemann-Pick disease type A begins in the individual’s first few months of life. Symptoms include the following:

    ◦Feeding difficulties

    ◦Abdominal enlargement within 3-6 months

    ◦Progressive loss of early motor skills

    ◦Rapid decline leading to death by the time the patient is aged 2-3 years

  • Niemann-Pick disease type B is similar to Niemann-Pick disease type A, but the symptoms are more variable.

    ◦Abdominal enlargement may be detected in early childhood.

    ◦Respiratory infections recur.

    ◦No neurologic involvement is present.

  • Niemann-Pick disease type C usually affects school-aged children, but the disease may occur at any time from early infancy to adulthood.

Symptoms may include the following:

◦Unsteadiness of gait, clumsiness, problems in walking

◦Difficulty in posturing of the limbs

◦Slurred, irregular speech

◦Learning difficulties and progressive intellectual decline

◦Sudden loss of muscle tone, which may lead to falls

◦Seizures

Tremors accompanying movement.

Histologic features:-

  • Niemann  – Pick cells are foamy, lipid – laden cells distributed throughout RES.

  • Positive for cholesterol & only weakly positive for ALP.

  • Affected cell becomes extremely large, enlarged secondary to distention of lysosomes.

Treatment:-

  • Enzyme replacement therapy currently being explored.

  • Current treatment symptomatic; consists mainly of antibiotic therapy for infections of pulmonary involvement.

  • Organ transplant (liver) also proposed

  • Overall prognosis poor.

References:-

Shafers’ 8th edition

Gaucher’s Disease

Dr. Kriti JainLeave a comment

Common LSD, characterized by deposition of gluco – cerebroside in cells of macrophage – monocyte system.

Results from mutation in gene or deficiency of enzyme that codes for glucosylceramidase.

Leads to accumulation of glucosylceramide in mononuclear phagocytic cells; transformed into “Gaucher cells“.

Five autosomal recessive variants exist resulting from distinct allelic mutations.

Three have been described in the literature.

Pathogenesis:-

  • Normally glycolipids derived from breakdown of senescent blood cells are sequentially degraded.
  • In this condition, degradation stops at level of glucosylceramidases.

  • These transit through blood as macromolecules; engulfed by phagocytic cells of the body.

  • These phagocytes “Gaucher cells” become enlarged due to accumulation of distended lysosomes

Type I – Chronic nonneuronopathic form:-

  • Presents in childhood with hepatosplenomegaly, pancytopenia & skeletal disease.
  • Most common variety, striking predilection for Ashkenazi Jews.

  • Characterized by clinical or radiologic bone involvement.

  • Spleen enlarges massively filling the entire abdomen.

Type II – Infantile/acute neuronopathic form:-

  • Rapidly progressive neurovisceral involvement.

  • Symptoms start before 2 years of age, very severe.

  • Results in death in infancy.

Type III – Juvenile/ Norrbotnian form:-

  • Patients are juvenile presenting with systemic involvement.

  • (intermediate between type I and type II).

  • Progressive CNS involvement usually begins in teens or early twenties.

Histologic Features:-

  • Numerous large, foamy, slightly granular cells with small, round, pyknotic nuclei – replace normal marrow structure.
  • Sternal puncture or biopsies of liver or spleen will reveal typical “Gaucher’s cell”.
  • Round, pale cell, 20 – 80µ, containing small eccentric nucleus & wrinkled or “crumpled silk” cytoplasm.

 

Treatment & Prognosis:-

  • Prognosis of Type II is very poor; death within first year.

  • Less virulent form may persist till 6th decade.

  • Administration of purified glucocerebrosidase results in dramatic decrease in hepatic accumulations of glucocerebroside.

  • Enzyme replacement therapy available; effective but extremely expensive.

REFERENCES:-

Shafer’s 8th edition