Neoplastic Diseases Of Skin 2007

NEOPLASTIC DISEASES OF SKIN

PONGSAK MAHANUPAB,M.D. Department of Pathology Faculty of Medicine

Integumentary System ( 330203) Sept.2

วัตถุประสงค์เชิงพฤติกรรม เมื่อสิ้นสุดการเรียนการสอน นักศึกษาสามารถ 1. ทราบชนิดเนื้องอกของผิวหนังที่พบได้บ่อย รวมทั้งซีสต์ของผิวหนัง 2. ทราบพยาธิกำาเนิดของเนือ้ งอกของผิวหนัง 3. ทราบลักษณะที่เห็นด้วยตาเปล่าและลักษณะที่เห็นจากกล้อง จุลทรรศน์ของเนื้องอกเหล่านัน้

Content 1. Tumors of epidermis - Squamous cell carcinoma - Basal cell carcinoma - Actinic keratosis

Content 2. Tumors of skin appendages - Syringoma - Trichoepithelioma - Sebaceous carcinoma

Content 3. Tumors of melanocytes - Nevus - Malignant melanoma 4. Tumors of blood and lymphatic vessels - Hemangioma, lymphangioma

Content 5. Cysts of the skin - Epidermal inclusion cyst 6. Tumor-like lesions of skin - Seborrheic keratosis - Keratoacanthoma - Keloid/hypertrophic scar

Tumors of Epidermis

SQUAMOUS CELL CARCINOMA •Most common skin tumor arising on sun-exposed sites of older people

•Occur anywhere on skin and squamous lining mucosa •Damaged skin ,scar from burn, stasis ulcer

• Predisposing factors : sunlight, industrial carcinogens ( tars and oils ), chronic ulcer and draining osteomyelitis, old burn scars, ingestion of arsenicals, ionizing radiation, tobacco and betel nut chewing

•Increase incidence in immunosuppressed patient ( chemotherapy, organ transplant ), xeroderma pigmentosum

Gross : - Nodular, ulcerated, scaly

•Histopathology - True invasive carcinoma - Irregular mass of atypical squamous cells proliferation downward into dermis ( breakthrough basement membrane )

Intercellular bridge

- Cell : - Hyperplasia - Polygonal shape - Nuclear hyperchromasia - Vary in size and shape ( pleomorphism ) - Intercellular bridge,atypical mitosis,

Keratin pearl

True invasive carcinoma Irregular mass of atypical squamous cells proliferation downward into dermis

Individual keratinization

Intercellular bridge

BASAL CELL CARCINOMA •Exclusively on hair bearing skin •Usually single •Adults •Do not metastasize

•Common, slow-growing •A tendency to occur at sites subject to chronic sun-exposed and in lightly pigmented people

•High incidence in immunosuppression and in patients with defects in DNA replication or repair

•Predisposing factors 1. Light skin color, prolong exposure to strong sunlight 2. Ray 3. Burn and other scars

•Gross - Pearly papules often with dilated subepidermal vessels ( telangiectasia ) - Some containing melanin pigment similar to nevi or

- Ulceration - Local invasion to muscle, bone and sinuses - Do not occur in mucosal surface

•Clinical 1. Noduloulcerative ( rodent ulcer ) 2. Pigmented 3. Morphea - like 4. Superficial 5. Fibroepithelioma

• Histopathology - Nodular mass of basaloid cells, extend into dermis - Cell

- Large, oval , elongated nuclei, little cytoplasm, poorly defined - No intercellular bridge - Nuclei : uniform , resemble basal cell, nonanaplastic - No abnormal mitosis, no

- Two patterns of growths 1. Multifocal ( multifocal superficial type ) - spreading many sq.cm. of skin surface 2. Nodular - growing downward into dermis as cords or islands

Continuation from basal cell layer

CONTINUATION FROM BASAL CELL LAYER

PERIPHERAL PALISADING

PROLIFERATI ON OF BASALOID CELLS

ACTINIC KERATOSIS - Premalignant lesion ( precancerous lesion ) - Result from chronic exposure to sunlight

- High incidence in lightly pigmented individual - Ionizing radiation, hydrocarbons, arsenicals may induce

•Gross - <1 cm. in diameter, tan brown, red or skin colored, scaly - Rough, sandpaper-like consistency - Increase keratin similar to cutaneous horn

- site of involvement :- sun exposure area ( face, arm, dorsum of hands ), lip ( actinic cheilitis )

•Erythematous scales somes are pigmented, peripheral spreading •Can develop into squamous cell carcinoma ( about 20 %),

Multiple lesions on areas exposed to sun

Minimally elevated, slightly scaly, flesh colored to pink

•Microscopic - Cytologic atypia at the lower most layers, may be associated with hyperplasia of basal cells - Atrophy:- thinning of epidermis - Basal cells:- dyskeratosis with pink or reddish

- Stratum corneum is thickened with retained nuclei ( parakeratosis )

- Presence of intercellular bridge - Dermis :- thickened, blue-gray elastic fibers (elastosis), a probable result of abnormal dermal elastic fiber synthesis by sun-damaged fibroblasts

focal or confluent parakeratosis Cellular atypia and mitotic figure in deep epidermal layer, may bud in to superficial dermis

Normal epidermis

HYPERKERAT OSIS AND PARAKERATO SIS

Tumors of Skin Appendages

SKIN APPENDAGE TUMORS

- Hundreds of benign tumor arising from appendages

- Often clinical nondescript, solitary or multiple papules or nodules - Some have a predisposition for occurrence on specific

- Syringoma :- lesions of eccrine differentiation , multiple small tan papules in the vinicity of the lower eyelid

Small papules, 1-2 mm., mainly at lower eyelid

Epithelial strands of small basophilic cells, characteristics of cystic duct ( commalike or tadpole ) lined by a doublelayer of flattened epithelial cells containing colloid material

- Trichoepithelioma :follicular differentiation, multiple , semitranslucent, dome-shaped papules - Face, scalp, neck, upper trunk

SEBACEOUS CARCINOMA - Most frequently on eyelid ( Meibomian gland ) - Easily mistaken from chronic blepharoconjunctivitis or

Gross: - Nodule, may or may not ulcerate

Great masquerader Chalazion - like

Microscopic : - Irregular lobular formation, variation in lobular size - Foamy cytoplasm of malignant cells

- Variation in size and shape of nuclei ( nuclear pleomorphism ) - Foamy cytoplasm, demonstration of fat by frozen section, staining with oil red O

Irregular lobular masses of cells resemble sebaceous cells, bizarre and invasive

Foamy cytoplasm

Fat stain ( Oil red O )

Pagetoid epidermal invasion

Tumors of Melanocytes

NEVUS ( MOLE , NEVOCELLULAR NEVUS, MELANOCYTIC NEVUS, PIGMENTED NEVUS )

•Benign neoplastic proliferation of melanocytes •Adolescent and early adulthood •Tan to brown , small < 6mm., solid papules, well defined round borders

•Microscopic - Presence of nevus cell (melanocyte ) arranged in clustered or nests - Level of nevus cell

JUNCTIONAL ACTIVITY

Junctional nevus - Well circumscribed nests either entirely within lower epidermis or bulging downward into dermis but still in contact with epidermis

NEVUS CELL

JUNCTIONAL

NEVUS

Compound nevus - Junctional + intradermal (dropping of) - Three types of nevus cells A, B and C

N

N COMPOUND NEVUS

Type A : upper dermis, “ epithelioid cell “ cuboid, abundant cytoplasm, varying amount of melanin pigment

TYPE CELL

A NEVUS

Type B : middle,

smaller, less cytoplasm,less melanin, resemble lymphoid cells

Type C : lower, resemble fibroblast or Schwann cells, elongated, spindleshaped nuclei, strands, rarely contain melanin

TYPE C NEVUS CELL

Intradermal nevus - No junctional activity

NEVUS CELL

MALIGNANT MELANOMA •Originate from melanocytes at DE - junction •More than half, arise de novo •Cause : sunlight, intermittent sunburn

• Presence of pre-existing nevus • Clinical warning signs 1. Enlargement of pre-existing mole 2. Itching or pain in pre-existing mole 3. Development of new pigmented lesion during adult life 4. Irregularity of border of

•Classification - Radial growth :

horizontally growth within epidermis and superficial dermis

- Vertical growth :

dermal layer as expansile

•Microscopic - Melanoma cell - larger than nevus cells, larger nuclei, irregular contour, prominent red nucleoli - Poorly formed nests or individual cells - Pagetoid invasion of epidermis

PROMINENT NUCLEOLUS

Pagetoid skin invasion

Tumors of Blood and Lymphatic Vessels

HEMANGIOMA - Extremely common, particularly in infancy and childhood about 7 % of all benign tumors - Most benign pediatric hemangiomas are capillary and cavernous

- Presence from birth and expand along with the growth of children - Many regress spontaneously at or before puberty

Capillary Hemangioma - Composed of blood vessels that resemble capillary, narrow, thin-walled, and lined by relatively thin endothelium - Grow rapidly in the first few months, begin to fade when the child is 1 to 3 years old, and regress by age 7 in 75-90% of

Gross : - Few millimeters to several centimeters - Bright red to blue - Level with the surface of skin or slightly elevated

Cavernous Hemangioma - Less common - Gross:- red-blue, soft spongy , 2 cm. - Microscopic : sharply defined, not encapsulated, large, cavernous vascular spaces, intravascular thrombosis with associated dystrophic calcification

Lymphangioma - Lymphatic analoque of the hemangioma - 1. Simple (capillary) lymphangioma 2. Cavernous lymphangioma (cystic hygroma)

Lymphatic space

Lymphatic space

Cysts of The Skin

EPITHELIAL CYST ( EPIDERMAL OR INFUNDIBULAR CYST ) •Slow growing, elevated, round, firm intradermal or subcutaneous tumor

•Histopathology - Wall : true epidermis ( infundibular epithelium ) - Content : horny material, laminated layer - Rupture : foreign body

CYSTIC CAVITY

W ALL

KERATIN CAVITY

FOREIGN BODY REACTION

Tumor-like Lesions

SEBORRHEIC KERATOSIS

• Very common, often multiple • Trunk, face,extremity (except palm,and sole ) • Do not appear before middle age • Sharply demarcated, brown , slightly raised, stuck on the

- Stuck on lesion - Sharply defined - Softly lobulated papule or plaque - Warty surface

•Histopathology - Hyperkeratosis, acanthosis - Basaloid cells: proliferation of small , uniform, relatively large nuclei - Horn cysts

ACANTHOSIS

Epidermal hyperplasia ( acanthosis )

Horn cyst

Proliferation of basaloid cells

PROLIFERATION OF BASALOID CELLS WITH MELANIN PIGMENT

HORN CYST

KERATOACANTHOMA •Solitary or multiple •Common, clinically and histologically resemble squamous cell carcinoma •Elderly •Firm,dome- shaped nodule 1 - 2.5 mm.

•Reach full size within 6 - 8 W, involuted spontaneously about one year •Increase incidence in immunosuppressed

Raised smooth edge and umbilicated, crusted center lesion

•Histopathology - Large center, irregular shape crater,keratin - Lips or buttress - Base : irregular epidermal

LIP

CRATER

LIP

dome-or cupshaped elevated wall central keratin mass

BASE

FIBROEPITHELIAL POLYP

• Acochordon, squamous papilloma, skin tag • Common • Middle age and old • Neck, trunk, face, intertriginous area • Soft, flesh - colored, baglike,

•Histopathology - Fibrovascular core - Benign squamous epithelium

KELOID / HYPERTROPHIC SCAR Initially have the same clinical appearance, red, raised, firm and posses smooth, shiny surface

Hypertrophic scars flatten spontaneously in 1 or several years, keloids persist and may even extend beyond the site of original injury

- Usually follow an injury - Occasionally, there is a familial predilection for keloid formation - Keloids are much more common in blacks than in whites

Microscopic - New collagen formation, arrangement of newly formed collagen - Collagen bundles are arranged in a whorl or nodular pattern

- Collagen: thick, highly compacted, hyalinized bundles lying in a concentric arrangement

Hypertrophic scars :- remain within boundaries of the wound, flat or slightly elevated

Keloids :- extending beyond the confines of the original wound and usually protruding prominently above the skin