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Page 1: HISTOLOGY AND FUNCTION - SRM University TUMOURS.pdf · ¾arise from keratinocytes epidermis ¾arise from actinic keratosis, leukoplakia, radiation ¾dermatitis, scars ... lymphatic

SKIN

HISTOLOGY   AND  FUNCTION

Page 2: HISTOLOGY AND FUNCTION - SRM University TUMOURS.pdf · ¾arise from keratinocytes epidermis ¾arise from actinic keratosis, leukoplakia, radiation ¾dermatitis, scars ... lymphatic

THREE  LAYERS  : EPIDERMISBASEMENT  MEMBRANE DERMIS

EPIDERMIS : COMPOSED  OF  KERATINOCYTESNO  MATRIXDEEP  BASAL  LAYER  MITOTICALLY ACTIVESPINOUS  LAYER – MATURE –HYALINHORNY  LAYER – AGED CELLS –SHEDTRANSIT  TIME: 40 TO 56 DAYSKERAINS  5 & 14

MELANOCYTES ORIGIN  FROM  NEURA  CREST1:35MELANIN – TYROSINE  &  CYSTEINEMELANOSOME  – TO  KERATINOCYTESDENSITY  OF  MELANOCYTES  CONSTANTMELANIN  PRODUCTION  INFLUENCED  BY MSH,  ACTH,  UV RAYS etc

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BASEMENT   MEMBRANE 

ZONE  ANCHOR  EPIDERMIS  TO  DERMIS  BY   PROTEIN STRUCTURES

DERMIS :

70%  OF   WEIGHT  COLLAGEN  TYPE  I  TENSILE  STRENGTH

ELASTIC  FIBRES

GROUND  SUBSTANCE  – POLYSACCHARIDE,  POLYPEPTIDES

FIBROBLASTS – THROUGHOUT  DERMIS – PROTEIN  MATRIX

NET WORK  OF  BLOOD VESSELS – PAPILLARY  DERMIS

GLOMUS  BODIES:

TORTUOUS   A‐V  SHUNTS – REGULATES   BODY  TEMPERATURE

SENSORY  NERVE ENDINGS – RECEPTORS,  PACINIAN,  MEISSNER, RUFFINI

FREE  NERVE  ENDINGS   MERKEL’S  CELLS,  HAIR  FOLLICLE

ADENEXCAL :  SWEAT  GLANDS – PALMS,  SOLE,  AXILLA

APPOCRINE  GLANDS – AXILLA,  PERINEUM  SCENT

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MALIGNANT TUMOURS

• EPIDEMIOLOGY

• EXPOSURE  TO  UV RADIATION

• CHEMICAL  CARCINOGEN – TAR,  ARSENIC ,  NITROGEN  MUSTARD

• HPV – SQUAMOUS  CELL CA

• RADIATION  DERMATITIS

• CHRONIC  IRRITATION – MARJOLIN’S  ULCER   etc

• IMMUNO  SUPPRESSION

• HIV

BASAL  CELL  CARCINOMA

SLOW  GROWING

RARELY  METASTASIS

LOCALLY  DESTRUCTIVE

SITES – FACE,  SCALP,  NOSE,  CHEEK

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PRE ‐ DISPOSING  FACTORSFAIR  COMPLEXIONRADIOATION  EXPOSURESUN  BURNSIMMUNO SURESSION

PATHOLOGYARISE  FROM  BASAL  LAYER  OF EPIDERMISPILOSEBACEOUS  ADENEXA

TYPES:a) NODULARb) SUPERFICIALc) MICRONODULARd) INFILTRATING e) SCLEROSINGINFILTRATING  AND  SCLEROSING  TYPES  MOST  AGGRESSIVE 10 %

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CLINICAL  FEATURES

PEARLY,  TRANSLUCENT  MASSRAISED  BORDERSULCERATEERYTHMATOUS  PATCHES,  SCALYSCARING, (DD.PSORIASIS, EZEMA)ISLANDS  OF  TUMOUR  EXTENDING  SURROUNDING

DIAGNOSISBIOPSY – SHAVE , PUNCH,  INCISION,  EXCISION

TREATMENTELECTRO  DESICCATION CURETTAGENODULAR  TYPE  LESS  THAN  2 cmSUPERFICIAL  ANY  SIZE90 – 98 %  CURE  RATE

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CRYOTHERAPY:

• LESION  2 cm ↓

• Scarring,  HYPOPIGMENTATION

• NO HISTELOGICAL  CONFIRMATION

• USED  ONLY  LESS  AGGRESSIVE  LESIONS

• NOT  USED  IN PERI ORAL, ORBITAL  AREAS

SURGICAL  EXCISION

CURE  RATE 90 %

MARGIN 2‐5 mm DEPEND  ON  SIZE

MOH’S  MICROGRAPHIC  SURGERY – PERI  ORAL  AREA

99 %  PRIMARY  96 %  RECURRENT  NASAL  ALA  LESIONS

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SQUAMOUS  CELL  CARCINOMA

MORE  COMMON  THAN BCCARISE  FROM  KERATINOCYTES  EPIDERMISARISE  FROM  ACTINIC  KERATOSIS,  LEUKOPLAKIA,  RADIATION DERMATITIS,  SCARS,  CHRONIC  ULCER,  BOWEN  DISEASE – INSITUSKIN  PATCHES,  NODULE – CENTRAL  INFLAMATIONINDURATION,  NECROSIS – OOZINGMETASTASES – DIRECT  INFILTARTION,  LYMPHATICHAEMATOGENOUS

AUSTRALIA:  HIGH  UV  EXPOSURERACE         : WHITE  COMPLEXIONSEX            : MALE / FEMALE 2:1AGE           : ABOVE  60 years

RISK  FACTORS: IONIZING  RADIATION,  ARSENIC etc

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DIFFERENTIAL   DIAGNOSISACTINIC   KERATOSISBCCMELANOMAKERATOACANTHOMAPYODERMA  GANGRENOSUMWARTS

INVESTIGATIONSCT,  MRI,  DEPTH  OF  INVASIONBIOPSY : PUNCH,  SHAVE,  INCISIONAL,  EXCISIONAL

HISTOLOGYNEST  OF  EPIDERMAL  CELLS – MIXTURE  OF  NORMAL  AND   ANAPLASTIC CELLSWELL   DIFFERENTIATED – EPITHELIAL  PEARL‐ CONCENTRIC  LAYERS  OFSQUAMOUS   CELLS  WITH  CENTRAL  KERANTINIZATIONPOORLY   DIFFERENTIATED  LACKS  HORN  PEARLSSPECIAL   STAINS :  S100 NEGATIVE  FOR   SCC

POSITIVE  FOR   MELANOMA

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STAGING – TNMPRIMARY   TUMOURTx – PRIMARY   TUMOUR  CANNOT  BE   ASSESSEDTo – NO  EVDIENCE   OF   PRIMARY   TUMOURT1  ‐ TUMOUR 2 cmT2 – TUMOUR 2‐4 cmT3 – TUMOUR   LARGER  THAN 4 cmT4 – TUMOUR  INVADES  DEEPER  STRUCTURES

REGIONAL  NODESNX – NODES  CANNOT  BE  ASSESSEDN0 – NO NODESN1 – SINGLE  IPSILATERAL  NODE – 3 cm N2 – a) SINGLE

b) MULTIPLEc) BILATERAL

METASTASISMX  ‐ DISTANT  METASTASIS  CANNOT  BE  ASSESSED M0 – NO  DISTANT  METASTASISM1 – DISTANT  METASTASIS  PRESENT

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TREATMENT :

DRUG  THERAPY

ACTINIC  KERATOSIS – 5‐FLUORORACIL TOPICAL

‐ DICLOFENAC GEL

‐ BIOPSY CONFIRMATION

SCC/BCC                     ‐ IMIQUIMOD 5 % CREAM

SUPERFICIAL                ‐ IMMUNE  MODIFIER  THROUGH  LESIONS  ONLY  INTERFERON,  CYTOKINES

PHOTODYNAMIC   THERPAY (PDT)

PHOTOSENSITIZING  DRUGS

LIGHT – ACTIVATES  OXYGEN,  FREE  RADICALS  DESTROY,  TARGETED TISSUE.

ALA – AMINOLEVULINIC ACID – SKIN   TUMOURS – ACTIVE

PROTOPORPHYRIN   IX

ACTINIC KERATOSIS, FACIAL  LESION  90 %

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SURGICAL   TREATMENTCURETTAGE  AND   ELECTROSURGERYREPEATED  SEVERAL   TIMESNO  SPECIMEN  AVAILABLE   FOR  HPE96 % CURE

CRYOSURGERYLIQUID  NITROGENCURE  97 %

EXCISIONLOCAL   EXCISION – HPE – 92 %  CURE4 mm  MARGIN – RECURRENCE  5 ‐8 %WELL  DIFFERENTIATED  LESIONS

MOH’S   MICROGRAPHIC   SURGERY

LESIONS   ARE   REMOVED IN STAGESHORIZONTAL   FROZEN   SECTIONING – PERIPHERAL   AND  DEEP MARGINS

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CURE  RATE SCC 96 %  IN  5  YEARSFOR  RECURRENT  SCC  90 %  CURE RATETISSUE SPARING – DISFIGUREMENT  IN  DISTINCT  MARGIN, GENITALPENILE  SHAFTLOCAL  ANAESTHESIA,  SAY  CASE  OF  SURGERY  COST  EFFECTIVEMOH’S SURGERY  NOT  USEFUL  IN  INVASIVE  LESIONSSENTINEL  NODE  BIOPSY

LASER SURGERYRADIATION  THERAPYOLDER  PATIENT,  NO  HPE

PREVENTIONSPF – SUN PROTECTING  FACTORCLOTHING SUNSCREEN’S – SPR 30↑ZINC  OXIDE, TITANIUM  OXIDEAPPLIED EVERY 30 MINTS  DURING   EXPOSURE

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MALIGNANT MELANOMAMALIGNANT   TRANFORMATION  OF MELANOCYTES MELANOCYTES  DERIVED  FROM  NEURAL CRESTSKIN, GIT,  BRAIN – ADULTSWHITE  POPULATION   HIGHESTASIAN’S  LOWEST

ETIOLOGY

FAMILY  HISTORYPOSITIVE  IN  5 – 10 %

PERSONAL

BLUE EYES,  FAIRSUN  BURNFRECKLINGNEVI ‐ DYSPLASTICIMMUNOSUPPRESSIVE   STATE

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SUN EXPOSURE

HIGH  U‐V  RADIATIONLOW  LATITUDEBLISTERING  SUN BURNSDYSPLASTIC  NEVI  OVER  A  TIME  MELANOMA

CLINICAL PRESENTATION 

ABCDEA ‐ ASYMMETRYB ‐ BORDER   IRREGULARC ‐ COLOUR  VARIATIOND ‐ DIAMETER  >  6 cmE  ‐ ELEVATED   SURFACE

ITCHING,  BLEED,  ULCERATION,  SATELITE  LESIONS

BIOPSY:  EXCISION / INCISION, 2 mm   MARGINFULL   THICKNESS   SKIN

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SAPPEY : LYMPHATIC   DRAINAGE   DEPEND  ONANATOMICAL  LOCATIONLYMPHATIC   OVER   LAP

HISTOLOGICAL  CLASSIFICATION

GROWTH   PATTERN

SUPERFICIAL SPREADING

70 %   OF   MELANOMACELLS   AT  DERMS – EPIDERAL   JUNCTIONMIGRATE   TO  S.GRANULOSUM  & CORNEUMPAPPILARY   DERMISFROM   DYSPLATIC  NEVUSFLAT,  ELEVATED  LATTER2 cm DIAMETER,  VARIGATED   COLOURS

NODULAR MELANOMAEXTENSIVE   VERTICAL   GROWTH   INTO   DERMIS  THAN   RADIAL

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15‐30 %BLUE  BLACKOCCUR   WITHOUT   PRE EXISTING   LESION

LENTIGO  MALGNA   MELANOMA

4 – 10 %  MELANOMASPINDLE   SHAPE   HYPERCHROMATIC  CELLSEPIDERMIS   ATROPHICSIZE 3 cms, FLAT, FRECKLE,  FACE, NECKARISE   IN  HUTCHINSON’S   FRECKLE  (LENTIGO MALIGNA)

ACRAL  LENTIGINOUS   MELANOMA

2‐8%  IN   WHITE30 – 60% IN  DARK   SKINNED   PEOPLEDERMO   EPIODERMAL   JUNCTION – INVASION   PAPILLAR   DERMISPALMS,   SOLES  , FLAT   IRREGULAR   BORDERS   ULCERATIONS

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DESMOPLASTIC MELANOMA

1%  RAREPERI  NEURAL   INVASIONHIGHER   LOCAL   RECURRENCELOWER   REGIONAL   METASTASIS

CLASSIFICATION  AND  STAGING

BRESLOW’STHICKNESS  0.75 mm  or   LESSTHICKNESS  0.75  – 1.5 mmTHICKNESS   1.5 – 4 mmTHICKNESS   > 4 mm

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CLARK

LEVEL  I – INVOLVES    EPIDERMIS  ONLY   IN  SITU

LEVEL  II – INVADES  PAPILLARY  DERMIS  ONLY

LEVEL  II  ‐ INVADES PAPILLART  & INTERFACE

LEVEL  IV – INVADER  RETICULAR DERMIS  NOT  SUB –CUTANEOUS  TISSUE

LEVEL  V – INVADES  INTO  SUB  CUTAEOUS  TISSUE

TNM  STAGING

T X ‐ PRIMARY  TUMOUR  CANNOT  BE  ASSESSED

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• T0 – NO  EVIDENCE  TUMOUR 

• T15 – IN SITU –INVOLVES  ONLY  EPIDERMIS

• T1  ‐ 1  mm LESS THICKNESS

• T2  ‐ 1‐1.2  mm  LESS  THICKNESS

• T3  ‐ 2‐4 mm  LESS  THICKNESS

• T4 ‐ > 4 mm , INVADES  SUB  CUTANEOUS   TISSUE 

SATELLITE  TUMOURS  WITHIN  2 cm

• a) TUMOUR > 4 mm

• b) WITHOUT  ULCERATION

• c) ULERATION 

REGIONAL  NODES

• NX – CANNOT  BE  ASSESSED

• N0 – NO REGIONAL  NODE  METS

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• N1 – ONE NODE 

• N2 – 2‐3 NODES

• N3 – 4 OR MORE

DISTANT   METASTASIS

• MX – DISTANT  METASTASIS  CANNOT  BE  ASSESSED

• M0 – NO DISTANT  METS

• M1 – DISTANT  METASTASIS

• a) SUB‐ CUTANEOUS  TISSUE  , NODES

• b) METASTASIS  TO  LUNG

• c)  METASTASIS  TO  OTHER  ORGANS

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MEDICAL MANAGEMENT

INTERFERON  (α 2BIFN)STAGE  III  MELANOMATOXICRELAPSE   REDUCED

GM‐CSF (GRANULOCYTE STIMULATING FACTOR)

STIMULATES  IMMUNE    SYSTEMNOT   TOXIC   AND  OVER ALL  SURVIVAL ↑STAGE   III &  IVPALLIATION   ONLY

CYTOKINE  AND   VACCINE   THERAPY

TUMOUR   SPECIFIC  TARGETS – ONCOGENE

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CDK4, TRP‐2, MART‐1AUTOLOGOUS (ALLOGENIC)

CHEMOTHERAPY

TEMOZOLOMIDEDACARBAZINE

SURGICAL  TREATMENT

STAGE – O :0.5 % TO 1.5 % cm MARGIN EXCISION IN‐SITU/OBSERVATION

STAGE – I : T₁  LESION1  TO  2 cms MARGINSENTINEL  NODE   BIOPSYCLOSURE – PRIMARY,   SKIN   GRAFTING

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STAGE II

2 cms MARGIN  – NO  ADVANTAGE   IN 4 – 6 cms MARGINSLYMPH ADENCTOMYSENTINEL   NODE  BIOPSY  IN  NO  NODES  CLINICALLYHYPERTHERMIC   ARTERIAL   LIMB   PERFUSION – MELPHALANADJUVANT   THERPAY

STAGE III

2 cm MARGINREGIONAL   LYMPHADENOCTOMY

STAGE IVREFRACTORYCONSIDER  FOR   CLINICAL  TRIALSDTC ,  BCNURADIATION

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THANK YOU