DermatopathologyDermatopathologySlide ReviewSlide Review--33

Paul K. Shitabata, M.D.Paul K. Shitabata, M.D.DermatopathologistDermatopathologist

Pathology Inc.Pathology Inc.

69 69 yoyo F complained of a mass on the F complained of a mass on the upper neck/base of scalpupper neck/base of scalp

EccrineEccrine spiradenomaspiradenomaCylindromaCylindromaBasal cell CABasal cell CAMerkel cell CAMerkel cell CA

EccrineEccrine SpiradenomaSpiradenoma

HistopathologyHistopathology

Nodules of Nodules of basaloidbasaloid cellscellsMixture of 2 cells typesMixture of 2 cells typesPerivascularPerivascular hyalinizationhyalinizationScattered lymphocytesScattered lymphocytesThymomaThymoma--likelike

CylindromaCylindroma

HistopathologyHistopathology

Low power Low power circumscribed nodulecircumscribed noduleCircumscribed nests of Circumscribed nests of basaloidbasaloid cellscellsCharacteristic Characteristic compartmentalization by compartmentalization by hyalinizedhyalinized BMBM

Basal Cell CarcinomaBasal Cell Carcinoma--with with micronodularmicronodular featuresfeatures

HistopathologyHistopathology

Nodules of Nodules of basaloidbasaloid cells cells showing minimal showing minimal atypiaatypiaDeep infiltrative growth Deep infiltrative growth patternpatternMinimal Minimal stromalstromalresponseresponse

Merkel Cell CarcinomaMerkel Cell Carcinoma

HistopathologyHistopathology

Small round blue cellsSmall round blue cellsHigh mitotic rateHigh mitotic rateNuclear moldingNuclear moldingStippled chromatinStippled chromatinEpidermal involvement Epidermal involvement occasionallyoccasionallyParanuclearParanuclear dotdot--like like reactivity for CK20, CKreactivity for CK20, CK

38 yr F complained of a lesion on her 38 yr F complained of a lesion on her left elbowleft elbow

SweetSweet’’s syndromes syndromeLeukemia cutisLeukemia cutisLeukocytoclasticLeukocytoclastic vasculitisvasculitisPustularPustular psoriasispsoriasis

SweetSweet’’s Syndromes Syndrome

HistopathologyHistopathology

Diffuse Diffuse neutrophilicneutrophilicdermatosisdermatosisNo No vasculitisvasculitisMay have secondary May have secondary vesicle/bulla formationvesicle/bulla formation

Leukemia CutisLeukemia Cutis

HistopathologyHistopathology

Depends upon Depends upon histologichistologicsubtypesubtypeSmall Small lymphocyticlymphocyticleukemia/CLL has leukemia/CLL has superficial and deep and superficial and deep and diffuse changesdiffuse changesRule out granulocytic Rule out granulocytic sarcomasarcoma

LeukocytoclasticLeukocytoclastic VasculitisVasculitis

HistopathologyHistopathology

Must have Must have fibrinoidfibrinoidnecrosis of small vesselsnecrosis of small vesselsNeutrophilsNeutrophils, nuclear , nuclear dust, hemorrhagedust, hemorrhage

PustularPustular PsoriasisPsoriasis

HistopathologyHistopathology

IntraepidermalIntraepidermal pustulepustuleNo No acantholysisacantholysisRule out Rule out dermatophytedermatophyteinfectioninfection

48 yr M complained of scaly lesion 48 yr M complained of scaly lesion on right index fingeron right index finger

Lichen simplex Lichen simplex chronicuschronicusVerrucaVerruca vulgarisvulgarisPorokeratosisPorokeratosisVerrucaVerruca plantarisplantaris ((myrmeciamyrmecia))

Lichen Simplex Lichen Simplex ChronicusChronicus

HistopathologyHistopathology

Irregular epidermal Irregular epidermal hyperplasiahyperplasiaHypergranulosisHypergranulosisDermal papillary fibrosisDermal papillary fibrosisOverlap with Overlap with prurigoprurigonodularisnodularis

VerrucaVerruca VulgarisVulgaris

HistopathologyHistopathology

Epidermal hyperplasia Epidermal hyperplasia with with papillomatosispapillomatosisInward bending of Inward bending of retereteridgesridgesVascular Vascular telangiectasiatelangiectasiaSuperficial Superficial koilocyteskoilocytes

PorokeratosisPorokeratosis

HistopathologyHistopathology

CornoidCornoid lamellaelamellaeEpidermal thinning in Epidermal thinning in center of lesioncenter of lesionLichenoidLichenoid dermatitisdermatitis

VerrucaVerruca PlantarisPlantaris ((MyrmeciaMyrmecia))

HistopathologyHistopathology

EndoEndo--exophyticexophytic papillary papillary proliferationproliferationViral inclusion bodies Viral inclusion bodies throughout most of throughout most of epidermisepidermis