Lesson 18. Pathology of the mucous membrane of the mouth and lips 2.pptx

maxiofacial surgery

1. Federal Educational Institution of Higher Professional Education Peoples' Friendship University of Russia Medical institute Department of pathological anatomy Pathological Anatomy of the Head and Neck

2. Lecture 20 Pathology of the mucous membrane of the mouth and lips

3. Multilayered flat non-corneating (keratinizing) epithelium It covers the outside of the cornea of the eye, conjunctiva, and lines the oral cavity (partially), pharynx, esophagus, vagina, cervix, and parts of the urethra. There are 3 layers: The lower one is basal, prismatic-shaped cells located on the basement membrane. Function - attachment to the basement membrane. The middle one is stratum spinosum , the cells are irregular, polygonal in shape. The upper layer is superficial, formed by flat cells. They die off and fall off from the surface of the epithelium.

4. Clinical and morphological elements of lesions of the oral mucosa Clinical and morphological elements of lesions of the oral mucosa are divided into primary and secondary. Primary - appear on the unchanged mucous membrane - it is a spot, nodule, node, vesicle, bladder, abscess, cyst, blister. Secondary - elements of the lesion of the oral mucosa - the stage of evolution of the primary elements: aphtha, erosion, ulcer, fissure, scar, scales, plaque, crust.

5. Primary elements: 1. Spot (macula) – roseola hyperemia d up to 1 cm; erythema – diffuse hyperemia. 2. Petechiae – spot hemorrhages, ecchymoses – extensive hemorrhages. 3. Pigmentation in the form of a border along the gingival margin or diffusely, under the action of lead, bismuth, mercury, silver. 4. Nodule ( papula ) – d 3-4 mm – elevation without a cavity, inflammatory infiltration by mononuclears . 5. Plaques – merging papules.

6. Primary elements: Node – (nodulus) is a dense, towering formation that captures the submucosal layer, observed in granulomatous inflammation, tuberculosis, syphilis, actinomycosis, etc. Vesicle – (vesicula) – d 1.5–4 mm – a cavity with serous exudate in the thorny layer of the epithelium. Bubble – (bulla) – more than a bubble, a cavity with exudate in the subepithelial layer (exudate serous, purulent, hemorrhagic). Cyst ( cysta ) – a cavity lined with flattened epithelium or connective tissue. Blister – ( urtica ) – asexual formation of 0.2–2 cm, as a result of acute swelling of the papillary layer.

7. Secondary elements: Aphthae is a superficial defect of the epithelium d 0.3–0.5 mm, the bottom with inflammatory infiltration. The defect is filled with fibrin (whitish-gray color). The outcome is the restoration of the epithelium without a scar. Erosion (erosio) is the same as afta, only the depression is crater–shaped, filled with fibrin and cells, it is often formed when opening the cavity elements. Heals without scarring. Ulcer (ulcus) is a defect of the epithelium and its own plate. The bottom is muscles, it is covered with fibrinous-purulent exudate, granulation tissue is at the bottom, papillomatosis, epithelial dysplasia are at the edges. The outcome is scarring. A fissure is a kind of ulcer – a deep, linear defect.

8. Secondary elements: 5. Cicatrix (cicatrix) – limited sclerosis of its own plate and submucosa, covered with regenerating epithelium. Keloid scar (hyalinosis) – a rough scar, with deformation, develops after necrosis of the oral mucosa. 6. Peeling ( sqama ) – desquamation of the scales of the horny epithelium in the hyperkeratosis zone. 7. Plaque is a surface overlay of fibrin with desquamation of the epithelium, contains leukocytes, bacteria, fungi, and is most characteristic of inflammation in candidiasis. 8. Crust – ( crusta ) – coagulated exudate on the surface of the epithelium and rejected with it.

9. Lichen planus Lichen planus (LP) is an autoimmune condition present on the skin, hair, eyes, mucous membranes, and nails. When the lesions present in the oral cavity, it is referred to as oral lichen planus (OLP), with OLP being found in 53.6% of cutaneous LP patients. OLP lesions appear as inflamed ulcerations that may have a white linear or lacy pattern. Usually, there is a constant presence of the lesions; however, the lesions will not remain in one area of the mouth or skin and tend to migrate over time.

10. Lichen planus of the oral mucosa

11. Clinic The lesions characterize by remissions and flares, "flare," meaning that the lesions will become much more proliferative and painful. When OLP is present, it is challenging for the patient to eat, drink, and function because of constant pain. OLP is more common in females over the age of 40 and in non-Asian countries. There are numerous possible causative agents for LP/OLP, the most common being pharmaceuticals and dental materials that produce a lichenoid reaction. If the lesions resolve when the causative agent is removed, it confirms a lichenoid reaction. If the lesions continue, then it is given the diagnosis of LP/OLP.

12. Classification

13. Reticular OLP Is the most commor form of OLP. In the mucous membrane, whitish (due to keratinization) papules are formed, which merge with each other to form a reticulated lace-like pattern or a bizarre plant pattern or rings, stripes, half-arches (Wickham's stretch marks) on the cheeks or buccal mucosa. These lesions are not static, they grow and shrink over weeks or months.

14. Microscopically Histologically, hyperkeratosis is noticeable, with possible parakeratosis, eosinophilic Sevatta’s bodies (apoptosis of epithelial cells). Typical are acanthosis with a pointed form of acanthotic cords (the form of a "saw tooth"). There is a pronounced lymphocytic infiltration of the lamina propia of the oral mucosa, which can lead to the destruction of the basement membrane. Bilateral involvement of the posterior buccal mucosa is more common, but the dorsal surface of the tongue, gums, and palate may be involved.

15. Erosive OLP In the central zones of erythematous atrophied areas of LP, erosions appear, less often ulcers. Along the periphery of mucosal defects, Wickham's stretch marks are observed. In contrast to the reticulated form, there is pain and discomfort in the oral cavity. Microscopically, the bottom of the ulcer is represented by granulation tissue with a chronic inflammatory infiltrate and covered with fibrinous masses.

16. Lichenoid reaction The term lichenoid reaction (lichenoid eruption or lichenoid lesion) refers to a lesion of similar or identical histopathologic and clinical appearance to lichen planus (i.e., an area which resembles lichen planus, both to the naked eye and under a microscope). Sometimes dental materials or certain medications can cause a lichenoid reaction. They can also occur in association with graft versus host disease.

17. Pemphigus. Pemphigus is an autoimmune disease in which intraepidermal blisters form in the skin. A distinction is made between common (vulgar), vegetative, erythematous, foliaceous, herpetiformis and drug-induced. The foliaceous form is not accompanied by lesions of the oral mucosa.

18. Pemphigus vulgaris Pemphigus vulgaris is the most common of all pemphigus and can lead to the death of the patient if left untreated. Middle-aged and elderly people are more likely to be affected. The etiology is not known. In about 50% of cases, this type of pemphigus begins with a lesion of the OM.

19. Morphology Changes can occur at any site of the OM, but the palate, cheeks, lips, gums, and ventral surface of the tongue are more commonly affected. Macroscopically, blisters with transparent fluid that quickly breaks open to form painful, bright red or whitish erosions. Along the periphery of the erosions, the remains of the blister cap are visible.

20. Morphology For histological diagnosis, it is necessary to excise material from the boundary zones of the blister or erosion. There is intercellular edema of the multilayered squamous epithelium in the early stages, then acantholysis develops in the spinous layer and a cleft is formed, and later a vesicle is formed, in the cavity of which fluid accumulates with the presence of Tzanck acantholytic cells (small round epithelial cells with a large dark nucleus and a narrow cytoplasmic rim around). To diagnose pemphigus, cytological examination of smears from the surface of erosions is also possible. The presence of Tzanck cells supports the diagnosis of pemphigus vulgaris.

21. Tzanck acantholytic cells

22. Bullous pemphigoid (benign non-acantholytic pemphigus) Is a chronic long-term disease with the formation of subepidermal blisters without the process of acantholysis. More common in patients over the age of 60 years, it is considered as a paraneoplastic process with the formation of autoantibodies to the proteins of the basement membrane of the epithelium. Mucosal lesions are usually painless and without pronounced salivation. At the beginning, edematous reddish spots are formed on the which appear blisters with a dense tire, quickly epithelialize the erosion after opening. The chronic course lasts for years with complete and incomplete remissions.

23. Pemphigus herpetiformis Pemphigus herpetiformis is a rare atypical bullous dermatosis that in some cases clinically resembles Dühring's dermatitis herpetiformis. Eruptions may present as plaques with papules and vesicles on the periphery or as grouped papules, vesicles, or tense blisters, as in Dühring's dermatitis herpetiformis. Pemphigus herpetiformis is characterized by severe itching of the skin. In the absence of adequate therapy, the disease can progress and acquire signs of pemphigus vulgaris or pemphigus foliaceus.

24. Stomatitis Stomatitis is a heterogeneous group of independent diseases of the oral mucosa of an inflammatory, infectious, infectious–allergic and allergic nature, as well as a local manifestation of skin, infectious, autoimmune and other diseases.

25. Candidiasis stomatitis. The causative agent is fungi of the genus Candida. Risk factors include primary (hereditary and congenital) and secondary, acquired (HIV infection, malignant neoplasms, malabsorption syndrome, diabetes mellitus, iatrogenic medications, etc.) immunodeficiency syndromes, as well as changes in the composition of the oral microflora (antibiotic therapy, poor hygiene, xerostomia) and some other factors (dentures, deficiency iron).

26. Acute stomatitis, pseudomembranous form (thrush) Is characteristic of patients with HIV infection and iatrogenic drug acquired immune deficiency after chemotherapy and radiation therapy of neoplasms. In the lesions, often multiple, there is a loosely adjacent pseudomembrane of white color, consisting of colonies of fungi, exfoliated cells of multilayered squamous epithelium, horny masses, bacteria, fibrinous exudate with an admixture of leukocytes.

27. Acute herpetic gingivostomatitis and pharyngotonsillitis caused by herpes simplex virus type I. It is more common in children aged 1 to 3 years. Swelling, hyperemia, bleeding and tenderness of the gums are observed, there are numerous painful vesicles on the mucous membrane, the opening of which leads to the formation of ulcers. Acute herpetic gingivostomatitis

28. Necrotising stomatitis (Noma or Cancrum oris) This occurs more commonly in poorly-nourished children like in kwashiorkor; infectious diseases such as measles, immunodeficiencies and emotional stress. The lesions are characterised by necrosis of the marginal gingiva and may extend on to oral mucosa, causing cellulitis of the tissue of the cheek. The condition may progress to gangrene of the cheek.

29. Inflammatory diseases of the oral mucosa of autoimmune nature Recurrent aphthous stomatitis is a chronic disease of unknown etiology characterized by the formation of painful ulcers ( apht ) on the mobile mucous membrane of the mouth, which recur with varying frequency. The first manifestation of RAS usually occurs between the ages of 10 and 30, women and non-smokers are more likely to be affected, because nicotine causes keratinization of the epithelium, and aphthae are formed in places of non-keratinizing epithelium.

30. Contributing factors: trauma of the OM, emotional stress; lack of certain substances – vitamin B12, iron, folic acid; hormonal changes in women, accompanied by recurrences during menstruation, remission during pregnancy, hypersensitivity to microorganisms. Immunopathological processes are of great importance in the pathogenesis of RAS, and patients with this disease have an increased level of autoantibodies to OM cell antigens.

31. Morphology This disease is characterized by small, whitish ulcers with red borders. The disease normally occurs as a single lesion or, infrequently, as multiple lesions on the wet mucous membranes of the lip, tongue, cheek or floor of the mouth.

32. Recurrent aphthous ulcer Histologically, ulcer floor represented by granulation tissue with chronic inflammatory infiltrate, covered with fibrinous-purulent masses. Spongiosis is observed at the edges of ulcerative defects in the epithelium, and chronic inflammatory infiltrates are visible in the lamina propria of the mucous membrane around the vessels.

33. Recurrent aphthous ulcer Hydropic changes IgG Elements of compliment Recurrent aphthous ulcer

34. There are 3 forms of aphthae: Small aphthae. They occur in 80% of RAS patients, more often in the anterior parts of the mouth. A prodromal period (1-2 days) is characteristic, during which erythematous spots appear, which turn into rounded or oval-shaped ulcers from 3 to 10 mm in diameter. The bottom of the aphthae is covered with a yellowish-gray coating, the edges are clearly defined and surrounded by a thin hyperemic rim (erythematous halo). The number of ulcers ranges from 1 to 5 during each recurrence. Healing takes 7-21 days.

35. Large or extensive aphthae (Sutton's disease). They occur in 10% of RAS patients. They are whiter, deeper, and larger than small ones. They are more common in the back of the mouth. During recurrence, 1 to 10 ulcers with a diameter of 10 to 30 mm occur.

36. Multilayered squamous epithelium of the oral mucosa in the initial phase of alteration. Pericellular edema, necrosis of keratinocytes. There is a large number of intraepithelial leukocytes in the necrosis area. There is a diffuse inflammatory infiltrate of neutrophils and lymphocytes in the submucosa. Ulcer of the oral mucosa. The epithelium in the center of the ulcer is necrotic. The bottom of the ulcer is covered with structureless necrotic masses, including leukocytes (shadow cells, pyknosis). Necrosis spreads into the submucosa, in which granulation tissue is detected.

37. Herpetiform aphthae Herpetiform ulcers are considered to be a separate nosological form. Such lesions manifest themselves as many recurrent small ulcers throughout the oral mucosa. They occur in 10% of patients with RAS. Frequent recurrence is characteristic, the formation of up to 100 ulcers with a diameter of 1-3 mm during one recurrence, the fusion of elements and the formation of larger ulcers are possible.

38. Reactive changes can occur in the epithelium: Epithelial hyperplasia is an increase in the thickness of the epithelial layer due to an increase in the number of cells of the basal layer and the layer of spiny cells. Epithelial atrophy is the thinning of the epithelial layer due to a decrease in the number of cells in the layers of the epithelium (epidermis) with a decrease in their volume and the disappearance of connective tissue papillae of the lamina propria in the mucous membrane. Epithelial metaplasia is the transition of one type of epithelium into another (non-keratinized multilayered squamous and cylindrical to keratinized multilayered squamous) due to the previous proliferation of cambial cells with altered differentiation. Acanthosis is a thickening of the epithelium due to a layer of spiny cells with their hyperplasia, with elongation of interpapillary outgrowths, but with the preservation of the basement membrane of the thickened epithelial layer.

39. Reactive changes can occur in the epithelium: Acantholysis is an irreversible process manifested by the formation of slits and blisters in the styloid layer of the epidermis and epithelium of the mucous membranes as a result of the disappearance of intercellular contacts in it. Spongiosis is characterized by excessive accumulation of serous fluid in the intercellular spaces of the spiny layer of the epidermis, which leads to their sharp expansion, stretching, and sometimes breaking of intercellular connections with the formation of cavities ( vesiculation ). Papillomatosis is a combination of acanthosis with overgrowth and enlargement of connective tissue papillary outgrowths of the epithelium (vegetation). May be combined with hyperkeratosis. Keratosis is a moderate thickening of the stratum corneum of the epithelium where it is present or occurrence where it is normally absent due to the appearance of keratohyaline in superficial spiny cells.

40. Spongiosis

41. Acanthosis of the mucous membrane with the presence of papillomatous outgrowths .

42. Reactive changes can occur in the epithelium: Hyperkeratosis is a significant and sometimes excessive thickening of the stratum corneum where it is normally present or the appearance where it is absent. Parakeratosis is a perversion of the keratinization process due to the loss of the phase of keratohyalin formation; In this case, the granular layer is absent, the rod-shaped nuclei of cells are preserved in the stratum corneum, which take a horizontal position. Dyskeratosis is a disorder of the process of keratinization of the epithelium, manifested in the appearance of individual cells undergoing keratinization in any layer of the epithelial layer, mainly in the zone of spiny cells. Pseudoepitheliomatous epithelial hyperplasia is an invasive acanthosis with deep penetration into the lamina propria of the mucous membrane or the dermis of epithelial strands and layers, sometimes with keratinization phenomena; The strands usually retain their connection with the cells of the basal layer. Atypism, dyskeratosis, cell polymorphism are absent. Epithelial dysplasia is a hyperplasia of cells of the basal layer of the epithelium without a tendency to differentiation and maturation, with the loss of the row and polarity of cells with the development of nuclear hyperchromia , atypia. This is a violation of the histostructure of epithelial tissue without destruction by cells of the basement membrane. According to the severity of atypia, there are 2 degrees of dysplasia (low and high). A low degree of dysplasia is considered a variant of hyperplasia. High epithelial dysplasia is actually a precancer. It is difficult to distinguish it from "cancer in situ".

43. Epithelial hyperplasia with hyperkeratosis

44. Hyperkeratosis of the mucous membrane of the tongue and cheek .

45. 49 Histological examination of hyperplasia of the epithelium of the oral mucosa reveals parakeratosis.

46. Pseudoepitheliomatous hyperplasia featuring acanthotic squamous epithelium showing irregular thick finger-like downgrowths into the underlying dermis. (H&E, ×20).

47. Fibromas Fibromas are the most common benign tumor growths in the oral cavity. They are a connective tissue response to irritations resulting in a well-defined, slow-growing firm mass. The overlying tissue (oral mucosa) is usually normal in appearance and color. A common site for irritation fibromas is the buccal mucosa, but they may be found throughout the oral cavity. After surgical removal, there is no recurrence. The biting line of the buccal mucosa is a common area for fibroma development. Fibromas are benign, mucosal-covered, traumatically-stimulated growths of fibrous connective tissue which are removed surgically by excision.

48. Fibroma on the oral mucosa has the appearance of a node with a smooth surface. Fibroma formation is often the result of occlusive trauma. On the micropreparation , fibroma is an exophytic node consisting of fibroblasts and collagen bundles.

49. Benign tumors of multilayered squamous epithelium Squamous cell papilloma is a benign tumor with exophytic growth, resembling cauliflower in its structure. This tumor is often found in people of different genders and ages, more often at the age of 30-50 years. The main cause is considered to be human papillomavirus types 6 and 11. Macroscopic picture: it has the form of papillary formation, sometimes in the form of "cauliflower", dirty gray, sometimes brownish in color, up to 1-2 cm in diameter, soft or dense consistency. Papilloma is localized on the soft palate, tongue, mucous membrane of the lips and gums in the form of single nodules up to 0.5 cm in size. Microscopic picture: Epithelium with a superficial layer of para- or hyperkeratosis. In the basal epithelial layer, the presence of mitosis is possible due to trauma and inflammation. Epithelial outgrowths surround the connective tissue stroma with dilated blood capillaries. Treatment is carried out by excision, recurrences and malignant transformation are usually not observed.

50. Squamous papilloma on the leg with a large number of outgrowths, resembling an ordinary wart. Depending on the degree of keratinization, squamous cell papilloma can be white, red or pink.

51. Papilloma of the oral mucosa

52. Genital warts (condyloma acuminatum) Genital warts (condyloma acuminatum ) are bulky soft outgrowths of pale pink color protruding above the surface of the mucous membrane with a heterogeneous surface of viral etiology. Human papillomaviruses of types 6 and 11 are detected in genital warts. Macroscopically, they present painless neoplasms with exophytic growth, more often located on the mucous membrane of the lips, soft palate and frenulum with a fine-grained surface of pink or reddish color, up to a diameter of up to 1.5 cm.

53. Morphology Histologically, a genital wart is a proliferation of multilayered squamous epithelium in the form of broad papillary structures without pronounced keratinization around a broad base with a vascularized connective tissue stroma . The terminal portions of the short epidermal ridges are dilated. After surgical excision of neoplasms, the formation of recurrences is often noted, malignant transformation, as a rule, is not noted. To prevent recurrence, vaccination against human papillomavirus types 6 and 11 is used.

54. Multifocal epithelial hyperplasia (focal epithelial hyperplasia) – Heck’s disease Is a multifocal proliferation of multilayered squamous epithelium on the oral mucosa of papillomavirus etiology. This disease is predominantly seen in predominantly female children and adolescents, originally described in the American Inuit Ethnic Group. Human papillomaviruses of types 13 and 32 are considered as etiological factors.

55. Morphology Macroscopically hyperplastic Foci are localized on the mucous membrane of the lips and cheeks in the area of tooth closure in the form of multiple papules 0.5-1 cm in size, which can undergo keratinization. Histologically, a slight hyperkeratosis and pronounced acanthosis are detected on the surface of the papules, in some keratinocytes there is koilocytosis, karyorexis . In children, as puberty progresses, there is a spontaneous regression of neoplasms.

56. Potentially malignant neoplasms of the oral mucosa and dysplasia of the epithelium of the oral mucosa Potentially malignant neoplasms of the oral mucosa are neoplasms with a high risk of transformation into squamous cell carcinoma. These include leukoplakia and erythroplakia . Smoking, alcohol abuse and betel nut use are considered to be the causes of such neoplasms, but etiological factors have not been identified for most of these neoplasms, including high-risk human papillomaviruses . Potentially malignant neoplasms occur in all parts of the oral mucosa, but erythroplakia is more often observed on the mucous membrane of the floor of the oral cavity and cheek. Clinically, red, white, and variegated neoplasms are the most suspicious. The risk of squamous cell carcinoma forming from potentially malignant neoplasms of the oral mucosa is low, and many of them can regress. Malignancy is observed in 1-2% of cases in flat leukoplakia, 12% in erythroplakia , and 60% in verrucous leukoplakia.

57. Leukoplakia Leukoplakia is the most common lesions of the oral mucosa (detected in 30% of people over 35 years of age, more often in men). Leukoplakia is a clinical concept describing white spots or plaques on the mucous membrane that cannot be attributed to other diseases (candidiasis, lichen planus, white spongy nevus, etc.) Microscopic picture: 80-85% of lesions show epithelial hyperplasia or hyperkeratosis, 5-15% – dysplasia, 2-5% - cancer. In 1-17% of cases, leukoplakia undergoes malignancy over the next 1-10 years.

58. Note Leukoplakia (white plaque) may be clinically defined as a white patch or plaque on the oral mucosa, exceeding 5 mm in diameter, which cannot be rubbed off nor can be classified into any other diagnosable disease. However, from the pathologist’s point of view, the term ‘leukoplakia’ is reserved for epithelial thickening which may range from completely benign to atypical and to premalignant cellular changes.

59. "Idiopathic" leukoplakia of the oral mucosa

60. Nicotine leukoplakia of smokers ( Tappeiner's leukoplakia) of the mucous membrane of the palate – in the form of white plaques with small red depressions corresponding to the excretory ducts of small salivary glands.

61. Hairy (fleecy) leukoplakia on the lateral surface of the tongue Hairy (fleecy) leukoplakia is a typical manifestation of HIV infection in the oral cavity. Fleecy growths (from which the HIV virus can be isolated) appear on the lateral surface of the tongue and the mucous membrane of the cheeks.

62. Displasia A reliable factor in malignancy of the epithelium of the oral mucosa is the presence of dysplasia. Dysplasia is detected in leukoplakia, erythroplakia , and erythrolikoplakia . Histologically, there is hyperplasia of cells of the basal layer of the epithelium without a tendency to differentiation and maturation, with the loss of the characteristic row and polarity, with the development of hyperchromia of the nuclei. Currently, there is a system of grading dysplasia according to the degree of impaired proliferation, maturity and differentiation of epithelial cells: low – with cell proliferation up to the middle of the epithelial layer, high – with signs of cell proliferation to the superficial epithelial layer. At the same time, cell atypia in carcinoma in situ on the oral mucosa is considered synonymous with high-grade dysplasia.

63. Low dysplasia (SIN 2) 1/2 of the oral mucosa High dysplasia cancer in situ of the oral mucosa

64. Despite the fact that the presence of dysplasia correlates with the formation of squamous cell carcinoma, most of these changes do not lead to the development of cancer. A 15-year follow-up of low- and high-grade dysplasia malignancy revealed malignancy in 18% and 39% of cases, respectively.

65. Proliferating verrucous leukoplakia Proliferating verrucous leukoplakia is an aggressive form of potentially malignant neoplasms of the oral mucosa. It is represented by a multifocal neoplasm that relapses with a high probability of malignancy. Proliferating verrucous leukoplakia usually occurs in women over the age of 60. The cause of occurrence has not yet been identified. It is located on the gingiva, alveolar processes and palate.

66. Clinically, it is characterized by four stages:

67. Verrucous leukoplakia

68. Morphology The histological structure of verrucous leukoplakia corresponds to clinical forms ranging from local verrucous hyperkeratosis without signs of dysplasia to pronounced dysplasia in the late stages of verrucous leukoplakia formation. In 70% of cases, verrucous leukoplakia degenerates into invasive cancer, which has a better prognosis compared to conventional squamous cell carcinoma of the oral mucosa.

69. Proliferating verrucous leukoplakia of the oral mucosa

70. Erythroplakia ( erythroplasia Keira)

71. Erythroplakia

72. Morphology Macroscopic picture: bright red velvety plaques, sometimes with a knobby surface, white or yellow spots of keratinization (keratosis). The red color of the lesions is due to the fact that the papillae of the subepithelial connective tissue penetrate high into the epithelium and contain dilated capillaries, and the epithelium itself is thin with slight keratinization. Lesions in the form of a mixture of white and red foci are called "speckled erythroplakia ".

73. Erythroplakia of the soft palate in the form of white plaques of various shapes with mottled areas of erythema. Microphoto reveals cancer in situ of the soft palate with pronounced cellular changes, including pleomorphism, atypical mitotic figures and dyskeratosis on the background of an intact basement membrane.

74. Erythroplakia of the hard palate with dysplasia, hyper- and parakeratosis of the mucous membrane.

75. Pathogenesis of malignant transformation of proliferating verrucous leukoplakia and flat leukoplakia Hyperkeratosis Proliferating Verrucous leukoplakia Verrucous carcinoma or squamous cell carcinoma Squamous carninoma Carcinoma in situ SIN 1 SIN 2 SIN 3

76. Algorithm for diagnosis and treatment of leukoplakia Hyperkeratosis Remove the reason Repeated extensive excision Squamous carcinoma cancer in situ Dysplasia * Excise and observe Oncological surgery Idiopathic white mucosal formations Mandatory biopsy Relapse Observation *-removal of low-grade dysplasia depending on the clinic

77. Malignant tumors from multilayered squamous epithelium

78. Squamous cell carcinoma Squamous cell carcinoma is a malignant tumor with squamous cell differentiation from the epithelium of the oral mucosa. As a rule, it occurs at the age of 40-60 years, in people prone to smoking, drinking alcohol, using betel nut, and the role of the human papillomavirus is not excluded. Squamous cell carcinoma accounts for more than 90% of malignant neoplasms of the oral mucosa. The most common localization is the mucous membrane of the tongue, the floor of the oral cavity, and the gums. Clinically, the tumor causes discomfort in the oral cavity, pain, may interfere with the movement of the tongue, and an inflammatory reaction.

79. Morphology Macroscopically, an erythematous dense nodular neoplasm with ulceration and raised margins is revealed. If the ulcer does not respond to treatment, this is the first sign of malignancy. Microscopically, the tumor is more often a well-differentiated or moderately differentiated squamous cell carcinoma with focal or trabecular clusters of large cells with pink cytoplasm, pronounced intercellular bridges, and rounded light nuclei. I n high-grade tumors, dyskeratosis and cancerous pearls are detected. As the differentiation of tumor cells decreases, polymorphism, hyperchromatism , and mitotic activity increase. Around the tumor foci, there is a pronounced inflammatory reaction in the desmoplastically altered stroma . On the periphery of the tumor focus, dysplastic changes in the oral mucosa are noted.

80. Squamous cell carcinoma of the oral mucosa 84

81. Squamous cell carcinoma of the oral mucosa,HPV16

82. Clinical characteristics

83. HPV-positive oropharyngeal squamous cell carcinoma (non-keratinized squamous cell carcinoma) Is associated with high-risk papillomavirus infection and differs epidemiologically, clinically, and morphologically from squamous cell carcinoma of the oral mucosa. Men aged 50-56 are more likely to be affected. The etiological factor is human papillomavirus type 16. The tumor forms in the area of the root of the tongue and palatine tonsils. It is clinically detected in the advanced stages of the disease in the form of a small tumor node secondary to cervical lymph node lymphadenitis.

84. Morphology Histologically, squamous cell carcinoma is represented by a non-keratinized tumor, without dysplastic changes in the superficial epithelium. The tumor forms from the epithelium above the palatine tonsils and grows downwards in the form of sockets and lobules with necrosis in the central part. Tumor foci are infiltrated by lymphocytes. Tumor cells are characterized by a high nuclear-cytoplasmic ratio and high mitotic and apoptotic indices. Keratinization of the tumor is not pronounced. Papillary, glandular-squamous, lympho-epithelial-like, sarcomatoid and small cell variants were revealed. At present, the gradation of this tumor has not been developed. The prognosis is better for HPV-positive tumors compared to HPV-negative tumors.

85. Subject XVIII. Pathology of the mucous membrane of the mouth and lips

86. Papilloma

87. 220.226 Warty (verrucous) leukoplakia of the tongue

88. Thanks for attention 92

89. Drawings

90. 219. Papilloma of oral mucosa. Tumor, covered with a mature stratified epithelium. Basal membrane is preserved. Stroma is represented by connective tissue. To indicate at the figure: 1- parenchyma, 2- stroma.  

91. 220, 226. Warty (verruque) leukoplakia of tongue. Thickening of stratified epithelium, acanthosis and enhanced keratinization. To indicate at the figure: 1 - acanthosis, 2 - hyperkeratosis.