BENIGN TUMORS OFEPITHELIAL ORIGIN DR. ABHAY KUMAR INTRODUCTION Characteristics: 1) Slow rate of growth and longer duration 2) Well defined mass of regular smooth outline (possesses a fibrous capsule ) 3) Swelling and pressure effect on surrounding structures 4) Smaller compared to malignant tumors 5) Displacement of adjacent normal tissues 6) Usually painless Benign Epithelial Tissue Lesions: 1) Papilloma 2) Keratoacanthoma 3) Squamous Acanthoma SQUAMOUS PAPILLOMA • A benign exophytic papillary growth of stratified squamous epithelium • 4th most common oral mucosal mass • 3-4% of all biopsied oral soft tissue lesions • Associated with papilloma virus (HPV type 6 and 11) • Low virulence and infectivity rate • Clinically and microscopically indistinguishable from Verruca Vulgaris (virus-induced focal papillary hyperplasia of the epidermis) Clinical Features: - Exophytic growth made up of numerous fingr like projections (roughened , verrucous or cauliflower surface) - <1cm in greatest diameter - Sessile or pedunculated and white(keratinized) or pink (nonkeratinized) , mostly solitary - Occurs on the soft palate, uvula , and ventral and dorsal surfaces of the tongue , gingiva and buccal mucosa - Painless , white or pink in colour - Occurs at any age - Papilloma like or papillomatous lesions as well as ‘pebbly’ lesions and fibromas of various sites in the oral cavity are recognized as manifestation of multiple hamartoma and neoplasia syndrome (Cowden’s syndrome) HISTOLOGICAL FEATURES: - Long , thin , finger-like projections extending above the surface of the mucosa Each made up of continous layer of stratified squamous epithelium Contains a thin , central connective tissue core (supports nutrient blood vessels) - Proliferation of the spinous cells in papillary pattern - May show basilar hyper plasia and mild mitotic activity (SHAFER’S) • A thick papillary layer of keratinized or non-keratinized squamous epithelium • A central core of fibrovascular connective tissue (characteristic) • Long and finger –like or short , rounded and blunt(papillary projections) • Normal maturation pattern shown by epithelium • Mild degree of basilar hyperplasia (SAPP) Differential diagnosis: Verruca vulgaris Oral condyloma acuminatum Focal epithelial hyperplasia (Heck disease) Treatment : - Surgical excision of the base of lesion and small area of surrounding normal tissue - Recurrence is uncommon Squamous Acanthoma Description :- Uncommon Lesion - Represents reactive phenomenon of epithelium - Not true neoplasm - Tomich and Shafer described lesion Clinical features:Age :- Older Adults Site of Occurance:- Any site on oral mucosa - Appears small flat or elevated - White , sessile or pedunclated lesion on mucosa Causes : - Trauma H/P features: - Elevated or Umblicated epithelial proliferation - Thickened layer of orthokeratin and underlying spinous layer of cells T/P: - Excision - No case of recurrence after excision KERATOACANTHOMA • Self –healing carcinoma ,molluscum pseudocarcinomatosum , molluscum sebaceum , verrucoma • A benign endophytic epithelial growth appearing as a wellcircumscribed keratin-filled crater on sun-exposed skin • Low grade malignancy , originates in pilosebaceous glands • Variant of invasive SCC (considered) - Occurs on: Hair-bearing skin (cheeks , nose , eyelids , ears ) Lower lip - Arises from hair follicle epithelium above sebaceous glands - Lower lip – arises from superficial epithelium of sebaceous ducts or from the hair follicle epithelium of adjacent skin Etiological factors: - Trauma , chemical carcinogens , human papilloma virus , genetic factors and immunocompromised status Clinical Features: Seen above >50yrs of age Male:female – 2:1 Less common in dark skinned individuals Occurs in sun exposed areas Face,neck,and dorsum of the upper extremities are common sites - 8.1% cases occurred on lips( vermilion border of both upper and lower lips are equally affected) • Develops rapidly over a period of 1to2months • Soliatry and benign as firm, round ,skin coloured or reddish papules • Rapidly progress to dome-shaped nodules with a smooth shiny surface and a central crateriform ulceration or keratin plug (projects like horn) • Appears elevated umblicated or crateriform(with depressed central core or plug) • 1 to 1.5cm in diameter • Painful often and regional lymphaedopathy present Differential diagnosis: Actinic keratosis Molluscum contagiosum Muir-Torre syndrome SCC Verrucous carcinoma Histological features: - Hyperplastic squamous epithelium growing in underlying connective tissue - Parakeratin or orthokeratin covers the surface with central plugging - Dysplastic features seen – occasionally (peripheral zone formed by squamous cells with atypical mitotic figures , hyperchromatic nuclei and loss of polarity ) - Pseudocarcinomatous infiltation typically presents a smooth , regular , well-demarcated front that does not extend beyond the level of the sweat glands - Connective tissue – shows chronic inflammatory cell infiltration - Characteristic features – seen at margins , normal adjacent epithelium elevated towards the central portion of crater (abrupt change in epithelium occurs as hyperplastic acanthotic epithelium is reached) (SHAFER’S) Features : - Central plug of keratin surrounded by a sharply demarcated - Cup-shaped buttress of normal epidermis - Epithelium pattern represents pseudocarcinomatous growth - Epithelium composed of well-differentiated spinous cells with abundant cytoplasm, minimal pleomorphism , infrequent mitotic figures , absence of abnormal mitotic figures TREATMENT: - Surgical excision - Recurrent tumors may require more aggressive therapy Benign pigmented lesion - Depending on amount and distribution of melanin in skin or mucosa, different color ranges seen - Brown - Basal cells - Black - keratin and Spinous cells - Dark blue – Deeper Connective Tissue ORAL NEVI • Oral melanocytic nevus , nevocellular nevus , mole , mucosal melanocytic nevi • Ackermann and field reported 1st case in 1943 • Benign proliferation of nevus cells either in epithelium or connective tissue • Benign , Pigmented ,acquired lesion* of skin or mucosa • Focal collection (nests) of rounded melanocytes (nevus cells) • Histologic location ,acquired nevi classified in 3 types : 1) Junctional Nevi: - Nevus cells limited to basal cell layer of epithelium 2) Compound Nevus: - Epidermis and dermis 3) Intradermal Nevus: - Nests of nevus cells in connective tissue *Nevi can be classified as congenital or acquired (Buchner and hansen) • Blue nevus : - A true mesodermal structure - Composed of dermal melanocytes - Spitz nevus (spindle cell or epitheloid cell nevus) : - known as juvenile melanoma - Common mucosal type : Intramucosal Nevus - 2nd common mucosal type : Blue Nevus • Junctional and compound nevus : 3-6% of all oral nevi • Oral acquired melanocytic nevi evolve through stages Junctional Nevi (infants , children & young adults) matures Compound Nevi Intramucosal Nevi Congenital Nevi • Ainsworth and her colleagues divided congenital nevi of skin : 1) Small Nevi: >1cm diameter (3-5 cm) 2) Garment Nevi : >10cm in diameter - covers large areas of skin - 1 to 2.5% of neonates - Flat , pale tan macules to elevated , verrucous, hairy lesions - Approx 15% - skin of head and neck - Intraoral occurrence is rare • Acquired nevi are common • Eight month of life and in number with age • Number of nevi as one ages • Clark stated “number of nevi a person has is genetically determined” • 85% - young patients (<40 years) 55% - white patients 23% - black patients Mean age for: 1) Junctional /Compound Nevi – 22 – 24 yrs 2) Intramucosal / Blue Nevi – 35-38yrs Predominant in women than in man Site of occurrence:hard palate -40% buccal mucosa – 20% Vermillion border of lip & labial mucosa gingiva – 10% Tongue and floor of mouth – 1 case reported • Asymptomatic , incidental finding on routine dental check up • Melanotic macules,amalgam tatoos , physiologic ethnic pigmentation , smoke’s melanosis or pigmented lesion • Differences :- melanotic macules and amalgam tatoos are flat while nevi are elevated from mucosal surface • 85% of oral nevi - pigmented - brown to black or blue • Nevi - well circumsribed ,round or oval , raised (65-80%) Anatomic distribution closely follows histologic type - 2/3rd of blue nevi – palate - Intramucosal : hard palate -25% buccal mucosa – 25% gingiva – 17% vermilion border of lip – 17% labial mucosa – 9% • H/P features:- Large ovoid, rounded or spindle –shaped cells with pale cytoplasm - Vesicular nucleus - Granules of melanin pigment in cytoplasm - Group in sheets or cords (nests or theques) • Intramucosal (Intradermal) Nevus: - common mole - common lesion of oral mucosa Clinical features:Young patients Asymptomatic, pigmented – brown to black Smooth flat lesion or elevated above surface Hard palate or gingiva Grows slowly Measures <1cm in diameter H/P features:- Nests , cords or sheets of nevus cells within connective tisssue - Multinuclested giant cells seen - Spindles cells may be present - Seperated from epithelium by well – defined band of connective tissue - Free of nevus cells • - Junctional Nevus:Benign , brown –black Skin , oral mucosa (occasional) Hard Palate or Gingiva H/P features:- No zone of demarcation - Nevus cell in contact and blend with surface epithelium - Overlying epithelium is thin ,irregular and shows cells crossing junction & growing down into connective tissue - Known abtropfung or dropping off effect - Feature showing malignant transformation ( junctional activity) • - Compond Nevus:Lesion Composed of two elements Common in skin than in oral mucosa Pigmented papulae or macule on hard palate or gingiva H/P features:- Combined characteristic seen ( intramucosal + junctional nevus) (nevus cells in basal region of epithelium and adjacent connective tissue) - Nests of nevus cells dropping off from epidermis • - Blue Nevus:True mesodermal structure Consisting of dermal melanocytes Rarely undergo malignant transformation Present at birth and early childhood Remains unchanged throughout life - Appears as big pigmented lesion - Dark blue , dome shaped papule or flat macule on skin or mucosa - Smooth and exhibit hair growing from surface - Color :– - Due to melanocytes resides deep in connective tissue overlying vessels dampen brown coloration of melanin BLUE tint seen • H/P features:- Two types : 1) Common Blue Nevus 2) Cellular Blue nevus 1) Common Blue Nevus: - Elongated melanocytes with long branching dendritic process lie in bundles - Parallel to epidermis - Middle and lower third of dermis - No junctional activity seen 2) Cellular Blue Nevus:- Large , round or spindle cell with pale vacuolated cytoplasm - Alveolar pattern arrangement seen • - Spitz Nevus:Children : on face or extremities 15% reported in adults Solitary , dome-shaped , pink to reddish brown papulae - Size < 6mm H/P features :- Composed of Pleomorphic cells of three types 1) spindle cells 2) oval 3) epitheloid cells - Mononuclear and multinucleated giant cell - Arranged in cicumscribed sheets - Junctional activity seen Treatment and Prognosis:1) Acquired Pigmented Nevus : - common occurrence - removal adviced – occur in area irritated by clothing (belt or collar line) or increase in size, deepen in colour or ulcerated Trauma to intradermal nevus doesnot induce malignancy 2) Congenital pigmented Nevus:- Great risk for transformation to malignant melanoma - Clark and Coworkers described B-K mole Syndrome (autosomal dominant condition) - large pigmented nevi - higher risk for development of melanoma - not intraoral • Conclusion:Surgical excision of all intraoral pigmented nevi adviced Due to chronic irritation of mucosa in all intraoral sites ( eating , toothbrushing) THANK YOU
Report "Benign and Malignant Tumors of Oral Cavity"