Granulation tissue (early scar): Reactive myofibroblasts look scary, but NOT CANCER! pathology video

Majocchi granuloma/tinea misdiagnosed as Zoster shingles clinically (tinea dermatophytosis fungal folliculitis pathology)

Acantholytic SCC Follicular Squamous Cell Carcinoma video

Basal cell carcinoma under microscope (with TONS of plasma cells!) video

It's NOT a "sebaceous" cyst! Epidermoid cyst/Dilated pore/Follicular Cyst under microscope pathology video

Rare Lung Cancer/Tumor: Epithelioid Hemangioendothelioma (EHE) vascular tumor pathology histology (video)

Panniculitis Dermpath Review (subcutaneous inflammation & fat necrosis) pathology histology video

Subcutaneous panniculitis-like T-cell lymphoma (alpha beta T-cell lymphoma) pathology histology video

Silicone granuloma with foreign body giant cells (ruptured silicone breast implant leak) pathology video

Lipodermatosclerosis (hard firm dark brown red thick skin lower legs from venous stasis) pathology video

Encapsulated fat necrosis mobile “lipoma” (moveable skin lump like a marble under skin pathology) video

Hidradenitis suppurativa (pus draining cysts in groin armpits pathology dermatopathology) video

Erythema Nodosum (painful red bumps/lumps on legs panniculitis fat necrosis inflammation pathology) video

Erythema induratum/Nodular vasculitis with necrotizing caseating granulomas (tuberculosis reaction) (video)

NOT "infected cyst/sebaceous cyst" - Ruptured epidermoid cyst & keratin granuloma under microscope (video)

Systemic Amyloidosis on abdominal fat pad biopsy with Congo red stain (pathology dermatopathology) video

Tumid lupus erythematosus (red firm skin plaques nodules on trunk) pathology dermpath video

Eosinophilic fasciitis (spectrum with morphea profunda) hard thick tight bound-down skin arms & legs video

Calciphylaxis: Painful Black Ulcers from Chronic Kidney Failure/End Stage Renal Disease (ESRD) video

Hibernoma - brown fatty tumor (vacuolated cells granular eosinophilic cytoplasm) video

Subcutaneous fat necrosis of the newborn (tender red-purple skin lumps in baby) histology pathology video

Lipoatrophy (fat atrophy): possible mimic of liposarcoma & signet ring carcinoma video

Lupus panniculitis (lupus profundus) - subcutis fat necrosis due to lupus erythematosus video

Pancreatic Panniculitis (fat necrosis with calcification saponification from pancreatitis) histology video

"Spitting Stitches" under microscope (perforating suture breaking out of skin after surgery) video

Stitches under a Microscope! (beautiful rainbow suture vicryl polarized light) video

"Gottlieb body" (eosinophilic inclusion) & Touton-like vacuolated melanocytes in nevus (pathology) video

"Mott cells" grape-like plasma cells with multiple pink vacuoles Russell bodies histology pathology video

Infectious Disease & Parasite Pathology Cases/Board Review (for UPenn Pathology Residents 2024) video

Acne keloidalis nuchae/folliculitis keloidalis: scarring bumps lumps hair loss on back of neck/scalp (video)

Verruca plana (flat wart) video

“Woo Cheal Cho lesion” epidermodysplasia verruciformis/verruca plana with eosinophilic inclusions video

Skeletal Muscle Histology & Muscle Fiber Atrophy video

Beautiful pink & green soap bubbles? Nope! Skeletal muscle atrophy on PAS stain! #PathArt #histology video

Lice & lice eggs/nits under the microscope (parasitology pathology head lice louse infestation) video

Amoeba infection under microscope (entamoeba amoebiasis) video

Giardia lamblia under the microscope (gastrointestinal parasite diarrhea from drinking river water) video

Bed bug (Cimex) (dermatoscope). Live & crawling around.

Rhinosporidiosis (Rhinosporidium seeberi) video

Scurvy (vitamin C deficiency) (corkscrew hair & hemorrhage, bleeding gums) video

Melanocytic Dermpath Board Review (melanoma, blue nevus, other nevi, & mimics) pathology dermatology video

Subungual acral melanoma (brown/black line under fingernail toenail nail) video

"Ancient" Nevus (benign nuclear atypia/symplastic change in melanocytic nevus) histology pathology video

“Nested" Melanoma: NOT Dysplastic Nevus!!! histology pathology dermatopathology video

Pigmented spindle cell nevus of Reed (Reed nevus - subtype of Spitz nevus?) pathology histology video

Ingrown Hair (ruptured hair follicle/cyst with hair shafts and granulomas) video

Metastatic Melanoma in a Lymph Node (under the microscope) video

Benign Nevus in a Sentinel Lymph Node (Capsular nevus with Ki-67/MART-1 immunostain) pathology video

Amalgam "tattoo" (metal particles causing oral mucosa dark spot after dentist cavity filling) video

"Blood blister" under microscope Talon noir subcorneal hemorrhage black spot on foot or hand skin video

Melanoma in tattoo (coincidence; tattoo didn't cause skin cancer) video

Foreign body granuloma & foreign body giant cells with gauze (pathology histopathology histology) video

Squamous cell carcinoma in situ (video)

Don't Curette Melanoma!!! Melanoma misdiagnosed as seborrheic keratosis & curetted into fragments (video)

Nodular Melanoma with satellite lesion video

Dysplastic nevus (compound dysplastic nevus with moderate atypia) short video

Squamous cell carcinoma short video

Desmoplastic Melanoma short video

Nevus + Neurofibroma (vs neurotized nevus) video

Combined Nevus (deep penetrating nevus/melanocytoma & congenital nevus) pathology dermpath (video)

Desmoplastic (Sclerotic) Spitz Nevus under the Microscope - pathology dermatology dermpath (video)

Metastatic Melanoma in Dermis (melanoma spread from primary skin location to other skin sites) video

Melanoma arising in a large congenital nevus (pathology dermpath dermatology dermatopathology) video

Deep penetrating nevus/melanocytoma - dark black mole beta catenin wnt signaling pathway pathology (video)

Nevus of Ito, Ota, Sun, Hori & Dermal Melanocytosis ("Mongolian Spot") under the microscope dermpath video

Blue Nevus under the microscope (blue/grey/black mole skin spot) video

Paget disease (breast cancer in nipple skin - nipple rash/sore/ulcer that won't heal) pathology video

Halo nevus (nevus with brisk inflammation) video

Spitz nevus with p16 immunohistochemistry video

Nevus mimicking hemangioma (pseudovascular/pseudoangiomatous nevus) pathology dermatopathology video

Lentigo maligna melanoma from chronic UV exposure sun damage (pathology dermpath dermatology) video

Cellular Blue Nevus (dumbbell spindle cell pigmented melanocytic lesion) video

Melanoma with regression (mimicking recurrent nevus & dysplastic nevus) video

“Pseudo-Melanoma” (recurrent nevus over scar after biopsy mimic of melanoma) video

Cellular Neurothekeoma (mimic of Spitz nevus, sarcoidosis, & granulomas) pathology dermpath video

Monsel’s “Tattoo” dark spot on skin from using Monsel’s solution (ferric subsulfate) after biopsy video

Heavily Pigmented Melanoma (mimic of blue nevus, pigmented epithelioid melanocytoma, or DPN) video

Live Scabies mites under the microscope - moving around on mineral oil skin scraping #parasites (video)

Cutaneous Syncytial Myoepithelioma (S100 & EMA +, Keratin -, EWSR1::PBX3 gene fusion) video

Cute Warty HAK (hypertrophic actinic keratosis) & squamous cell carcinoma (pathology histology) video

Soft Tissue Pathology Case Discussion for FedPatMex 2023: lipoblastoma, Kaposi, angiosarcoma, & more VIDEO

Folliculitis inflamed hair follicle under microscope (w/ Gram positive cocci bacteria on Gram stain) video

Angiofibroma (fibrous papule) with multinucleated giant cells pathology dermatopathology

Angiofibroma (fibrous papule) with multinucleated giant cells digital slide

Tricky Nodular Kaposi Sarcoma - NO extravasated blood! Pathology dermatology dermatopathology video

YIKES! Angiosarcoma hiding in a ruptured cyst! Sarcoma pathology dermatology dermatopathology video

Angiosarcoma hiding in a ruptured cyst! Digital slides

Dedifferentiated Liposarcoma with Meningothelial Whorls - sarcoma pathology video

Lipoblastoma (benign fatty tumor in kids - can mimic myxoid liposarcoma) soft tissue pathology video

Sclerosing Epithelioid Fibrosarcoma (related to low grade fibromyxoid sarcoma) pathology

Metabolism & Deposition Diseases in Skin (dermatology dermpath pathology board review) video

Deep Granuloma Annulare vs Rheumatoid Nodule (palisaded necrobiotic granuloma) pathology dermpath video

Systemic Amyloidosis on abdominal fat pad biopsy with Congo red stain (pathology dermatopathology) video

Tumid lupus erythematosus (red firm skin plaques nodules on trunk) pathology dermpath video

Calcified pilomatrixoma under the microscope (mimic of osteoma cutis calcinosis cutis) dermpath video

Amyloid under the microscope (nodular vs systemic amyloidosis AL light chain) dermpath pathology

Amalgam "Tattoo" black spot in gums/gingiva from metal cavity filling (dermpath oral pathology)

Gelfoam in a dermatofibroma (pathology dermpath dermatology dermatopathology) video

Seborrheic Keratosis with keratin amyloid and amyloid P stain pathology dermpath dermatology

Scleredema (firm hard thick skin on upper back) with colloidal iron mucin/myxoid stain

Scrotal Calcinosis (Multiple Skin Bumps/Nodules on Scrotum)

Digital myxoid cyst (digital mucous cyst) - translucent skin bump/papule near fingernail

Scar with injected steroids (Kenalog triamcinolone) pathology

Ganglion cyst under the microscope (synovial cyst; Baker's cyst) pathology

Focal cutaneous mucinosis (focal dermal mucinosis) pathology

Nephrogenic systemic fibrosis from Gadolinium MRI contrast (pathology dermatology dermatopathology)

Macular amyloidosis (cutaneous keratin derived amyloid)

Cutaneous Myxoma (superficial angiomyxoma) pathology

Gout in Bone (Toe Amputation for Gout plus possible osteomyelitis) pathology podiatry orthopaedics

Monsel’s Solution "Tattoo" (causing Skin Hyperpigmentation at Biopsy Site)

Pretibial Myxedema (thyroid dermopathy of Graves disease hyperthyroidism)

Oxalate (Oxalic Acid) Crystals Under the Microscope (cutaneous oxalosis)

Morphea skin disease (localized scleroderma) histology pathology

Scleromyxedema (with colloidal iron stain) pathology

Zinc/Vitamin Deficiency (acrodermatitis enteropathica, pellagra, & necrolytic migratory erythema)

Ochronosis (dark skin pigmentation caused by hydroquinone skin lightening cream or alkaptonuria)

Subepidermal Calcified Nodule (eyelid face skin bump in kids - a type of calcinosis cutis)

Mucocele (Bump on Lip from ruptured salivary gland/duct) oral pathology dermpath

Argyria (blue skin from colloidal silver) under the microscope (pathology dermpath dermatology)

What's that Pink Stuff??? Lipoid proteinosis vs Amyloidosis vs Colloid Milium (dermpath pathology)

Nerve vs Smooth Muscle Histology (fasicles of pink spindle cells) video

Paraganglioma under the microscope (carotid body paraganglioma) pathology video

Synovial Chondromatosis (cartilage nodules in joint synovium) video

Lipoma arborescens (synovial lipomatosis) - benign polypoid fat mass in joint space (pathology) video

Solitary bone cyst aka Unicameral bone cyst [UBC] aka Simple bone cyst (pathology orthopedics) video

Traumatic Neuroma & Peripheral Nerve Histology Discussion (short video)

Lipidized Dermatofibroma plus Tattoo (video)

"Ancient" Schwannoma (with benign degenerative atypia/pleomorphism) video

Atypical Fibrous Histiocytoma (atypical dermatofibroma): a mimic of sarcoma (video)

Epithelioid fibrous histiocytoma (EFH) an ALK-1 positive spindle cell tumor (pathology dermatology) video

Atypical fibrous histiocytoma (atypical dermatofibroma) (WSI digital slide)

Soft Tissue Pathology (epithelioid fibrous histiocytoma ALK-1, atypical FH, paraganglioma, and more) video

Vascular Tumors of Skin (31 cases in 3 hours): Board Review for Pathology Dermatology Dermpath (video)

Radiation-associated Angiosarcoma & post radiation therapy reactive changes (short video)

Vascular malformation under the microscope (aka cavernous hemangioma) short video

Microvenular hemangioma (potential mimic of Kaposi sarcoma) short video

Temporal arteritis (giant cell arteritis) under the microscope (headache, jaw pain, vision problems = emergency!) video

Venous Lake under the microscope (video)

Superficial angiomyxoma (cutaneous myxoma) video

Spindle cell hemangioma (video)

Pilomatrixoma under the microscope (with calcification & metaplastic bone ossification) short video

Venous Insufficiency under the microscope (vascular stasis changes) short video

Solar purpura (purple bruise like areas on elderly sun damaged skin) short video

Nodular stage Kaposi sarcoma (short video)

Tufted angioma/Kaposiform Hemangioendothelioma (short video)

Targetoid hemosiderotic hemangioma (hobnail hemangioma) short video

What is hobnail??? Vascular tumor basics short video

10 Classic Head & Neck Dermatopathology Unknown Cases (video)

"Ancient" Schwannoma (benign degenerative nuclear atypia and pleomorphism)

"Wolverine sign" clue for foreign body granuloma (silica in this case) video

"Ankle type" DF (lipidized dermatofibroma)

Acquired digital fibrokeratoma

Accessory Nipple: Dermpath in 5 Minutes (video)

All That Is Honeycomb Pattern Is Not DFSP! Tips, Tricks, & when to use FISH (Pathology Dermatopathology)

AFX (atypical fibroxanthoma) & PDS (pleomorphic dermal sarcoma)

Alveolar rhabdomyosarcoma in skin mimicking Merkel cell carcinoma

Aluminium chloride (drysol) deposition at prior biopsy site scar

Amyloidosis (nodular vs systemic) (AL light chain type amyloid)

Aneurysmal dermatofibroma (dermatofibroma with internal haemorrhage)

Angiofibroma (fibrous papule): clinical mimic of basal cell carcinoma

Angiokeratoma (short video)

Angioleiomyoma (leiomyoma, vascular type) painful skin bump often on leg (short video)

Angiomatoid fibrous histiocytoma

Angiosarcoma under the microscope (explained in 5 minutes) short video

"Arteriovenous" Hemangioma (short video)

Atrophie blanche (livedoid vasculopathy)

Atypical cellular neurothekeoma

Atypical Mycobacteria Infection (non-leprosy, non-tuberculosis AFB) with Stellate Abscess & Granuloma: 5-Minute Pathology Pearls video

Axillary Granular Parakeratosis: 5-Minute Pathology Pearls

Bacterial & Fungal Infections: Dermpath Board review video

Basic Dermpath Cases 1

Basic Dermpath Cases 2

Basic Dermpath Cases 3

Basic Dermpath Cases 4

Basic Dermpath Cases 5

BCC Escaping! Basal cell carcinoma falling out of tissue section (due to cleft artifact)

Bednar tumour dermatofibrosarcoma protuberans (DFSP with melanin pigment)

Beware the CD34 Halo in dermatofibroma (not DFSP)

Bite fibroma in mouth (aka irritation fibroma/oral fibroma)

Blue Nevus

Botfly larva (fly maggot) in skin (myiasis pathology dermpath dermatology dermatopathology)

Botfly (fly larva/maggot in skin) dermatobia hominis tropical parasite myiasis pathology

Botfly under the microscope (dermatobia hominis larva skin biopsy)

Bowenoid papulosis (HSIL high grade squamous intraepithelial lesion high risk HPV dermpath)

Branchial Cleft Cyst: 5-Minute Pathology Pearls (video)

Bronchogenic Cyst: 5-Minute Pathology Pearls (video)

Bug bite under the microscope aka "arthropod assault" (patient had scabies)

Bullous Impetigo vs Staphylococcal Scalded Skin (SSSS): 5-Minute Pathology Pearls video

Calcifying aponeurotic fibroma: rare benign hand/foot tumor in a child (soft tissue pathology)

Calciphylaxis (deadly complication of chronic kidney disease renal failure)

Calciphylaxis (complication of ESRD chronic kidney disease)

Cat Scratch Disease (Bartonella henselae): 5-Minute Pathology Pearls video

Cellular Dermatofibroma & Aneurysmal Dermatofibroma 101

Cholesterol emboli - artery blocked by detached fragment of atherosclerosis plaque

Candida Yeast Infection of Skin (Candidiasis) 5-Minute Pathology Pearls Dermatology Dermatopathology video

Chronic sun/tanning skin damage seen under the microscope (skin wrinkles solar elastosis dermatology) video

Chromoblastomycosis (Dematiaceous Fungus): 5-Minute Pathology Pearls (video)

Churg-Strauss syndrome (eosinophilic granulomatosis with polyangiitis EGPA vasculitis) pathology

Clear cell acanthoma

Clonal Seborrheic Keratosis (Borst–Jadassohn Phenomenon): 5-Minute Pathology Pearls (video)

CMV cytomegalovirus infection in skin ulcer

CNH (Chondrodermatitis nodularis helicis)

CNH: Chondrodermatitis Nodularis Helicis (Dermatology Mimic of Squamous Cell Carcinoma of Ear) video

Condyloma Lata (Syphilis): 5-Minute Pathology Pearls video

Crazy Mast Cells with Non-specific Immunostaining: 5-Minute Pathology Pearls

Condyloma acuminatum

Cryoglobulinemia type 1

Cutaneous Ciliated Cyst: 5-Minute Pathology Pearls (video)

Cutaneous Hemepath 101

Cutaneous Horn: Everything You Need to Know (video)

Cutaneous Myxoma (superficial angiomyxoma)

Cutaneous Soft Tissue Dermpath Unknown Cases for Emory Dermatology

Cystic Molluscum: 5-Minute Pathology Pearls (video)

Cylindroma

Dermatofibroma 101

Dermatofibroma 101 video

Dedifferentiated spindle cell melanoma with osteosarcoma & chondrosarcoma heterologous differentiation

Dermatofibroma with basaloid follicular induction

Dermatofibroma with "monster cells" (scary name, benign tumour)

Dermatofibroma with basaloid follicular induction (mimic of basal cell carcinoma)

Dermatofibroma with hemosiderin laden Touton giant cells

Dermatofibroma with induction phenomenon

Dermatology Emergencies Every Pathologist Should Know

Dermatomyofibroma vs fibroblastic connective tissue nevus (mimic of DFSP)

Dermatopathology Board Review for Dermatology Pathology Dermpath (19 Classic Cases) video

Dermatopathology Pearls for Head & Neck / Oral & Maxillofacial Pathologists

Dermatopathology Pearls for Head & Neck / Oral & Maxillofacial Pathologists video

Dermoid Cyst: 5-Minute Pathology Pearls (video)

Dermatopathology Unknown Cases (for Stony Brook Dermatology Residents) video

Dermpath Board Review: Hyaluronic Acid Filler, Trichoblastoma, Blue Nevus, Lupus & More

Dermpath Board Review: Pemphigus, Tattoo, Tick, Mycosis Fungoides, Keloid, Langerhans Histiocytosis and more

Dermpath Clues: Acute Ischemia in Skin (video)

Dermpath misdiagnosis pitfall! Patch Stage Kaposi sarcoma (video)

Dermpath Pearls & Pitfalls for General Surgical Pathologists

Dermpath Slide Session with the Mayo Clinic Pathology & Dermatology Residents

Dermpath Soft Tissue Pathology Cases for Australasian Dermatopathology Society 2022 meeting

Dermpath Soft Tissue Unknowns - 12 Cases for Australasian Dermatopathology Society 2022

Desmoplastic Trichoepithelioma (with perineural involvement!) video

DFSP (dermatofibrosarcoma) with perfect storiform pattern

DFSP 101 (dermatofibrosarcoma protuberans - sarcoma that mimics cyst lipoma scar)

DFSP mimicking dermatofibroma (dermatofibrosarcoma protuberans with epidermal induction & collagen trapping)

Digital Mucous Cyst vs Ganglion Cyst: 5-Minute Pathology Pearls (video)

Diffuse neurofibroma in neurofibromatosis NF1 (round nuclei & tiger stripe pattern & Wagner Meissner bodies)

Digital mucous cyst (Digital myxoid cyst) similar to ganglion cyst

Dysplasia in lichen sclerosus (differentiated vulvar intraepithelial neoplasia dVIN)

Discoid Lupus Erythematosus

Dysplastic Nevus Explained in less than 5 Minutes (video)

Ecthyma Gangrenosum (Pseudomonas aeruginosa) 5-Minute Pathology Pearls Dermatology Dermatopathology video

EED (Erythema elevatum diutinum) fibrosing vasculitis (short video)

"EHKoma" (epidermolytic hyperkeratotic acanthoma - solitary lesion of epidermolytic hyperkeratosis)

Elastofibroma dorsi (mass under scapula tip with beaded elastic fibres)

Epidermodysplasia Verruciformis (EDV) variant of flat wart verruca plana

Epithelioid angiosarcoma (CD34 negative)

Epithelioid fibrous histiocytoma (benign ALK1+ skin tumour; ALK gene fusion)

Epithelioid fibrous histiocytoma with signet ring & xanthomatous cells video

Epithelioid hemangioma/angiolymphoid hyperplasia with eosinophilia (ALHE)

Epithelioid hemangioma (angiolymphoid hyperplasia with eosinophilia; ALHE) short video

Epithelioid hemangioendothelioma (EHE)

Pyogenic granuloma (lobular capillary hemangioma) (short video)

Polypoid Dermatofibroma, aneurysmal type (aka sclerosing "hemangioma”) short video

Mucin/Myxoid change around sweat glands/eccrine coils: what does it mean? (short video)

Erythema Induratum/Nodular Vasculitis

Erythrasma (Corynebacterium minutissimum): 5-Minute Pathology Pearls Dermatopathology Dermatology video

Erythema nodosum panniculitis

Ewing sarcoma arising in skin

Erythema nodosum leprosum (a vasculitic reaction to leprosy)

Exogenous Ochronosis (possible side effect of hydroquinone skin lightening cream) same pathology as alkaptonuria

Fibrin Thrombus (short video)

Fibrohistiocytic Dermpath Basics - dermatofibroma & mimics

Fibrohistiocytic Skin Tumors 101 (Australasian Dermatopathology Society 2022 meeting)

Fibrosarcoma & Herringbone Pattern Explained in 5 Minutes

Fibrous hamartoma of infancy

Fibroma of tendon sheath (explained in 5 minutes) video

Fibrous hamartoma of infancy explained in 5 minutes

Fibrous papule (angiofibroma): skin bump on nose mimic of basal cell carcinoma

Focal cutaneous mucinosis (focal dermal mucinosis)

Follicular mucinosis & folliculotropic mycosis fungoides (cutaneous T-cell lymphoma) short video

Fournier gangrene: acute necrotic scrotum infection (pathology dermatology dermpath urology) video

Flat wart under the microscope (verruca plana)

FS-DFSP with PDGFD fusion (fibrosarcomatous dermatofibrosarcoma protuberans)

FS-DFSP (fibrosarcomatous dermatofibrosarcoma protuberans)

Gelfoam in skin

Genital warts under the microscope (Condyloma HPV pathology dermpath dermatology dermatopathology)

Giant cell arteritis/Temporal arteritis (headaches jaw pain vision loss)

Giant cell arteritis (temporal arteritis)

Giant cell tumor of tendon sheath 101 pathology

Giant cell fibroblastoma (paediatric variant of dermatofibrosarcoma protuberans - DFSP)

Glomangioma/Glomuvenous Malformation (glomus tumor with lots of vessels) short video

Glomeruloid hemangioma (classic vascular tumor in POEMS syndrome) short video

Glomus tumor (short video)

Glomus tumour with oncocytic & clear cell change mimic skin adnexal tumour

Giant cell tumour of tendon sheath

Granuloma annulare (video)

Gout (gouty tophus)

Gout crystals fixed in ethanol (monosodium urate uric acid gouty tophus birefringent needle shaped) (short video)

Hailey-Hailey Disease ("benign familial pemphigus") erosive blistering disease of groin and axillae

Keratin Amyloid (Lichen amyloid vs Macular amyloidosis) (NOT systemic amyloidosis)

Gout & Pseudogout (calcium pyrophosphate deposition disease - chondrocalcinosis)

Granuloma faciale (with EED/erythema elevatum diutinum-like fibrosis)

Hand foot and mouth disease (HFMD Coxsackievirus)

Herpes (acantholytic blister with neutrophil pustule)

Herpes Hair Follicle Infection (Herpetic Folliculitis) with follicle and sebaceous gland necrosis

Hemosiderin Halos / Ladybird Cells in Giant Cell Tumor of Tendon Sheath

Hibernoma (benign brown fat tumor) video

Hidradenitis suppurativa

Hidradenoma (Acrospiroma) short video

Hidrocystoma: 5-Minute Pathology Pearls

How sunburn looks under the microscope (sunburn cells in a solar lentigo) video

How to diagnose a rash on skin biopsy (basic approach – short video)

How to examine skin cancer excision specimen after biopsy (to evaluate for residual tumour)

Hypertrophic scar under the microscope with injected kenalog steroid

Immunohistochemistry in Normal Skin: Cytokeratins

Immunohistochemistry in Normal Skin: p63, EMA, desmin, SMA, CD34, Factor XIIIa

Infantile digital fibroma (inclusion body fibromatosis)

Inclusion Body Fibromatosis (Infantile Digital Fibroma/Fibromatosis) in 5 Minutes

Infantile hemangioma ("Strawberry birthmark") under the microscope (short video)

Inflamed seborrheic keratosis with keratin amyloid

Intraneural epithelioid MPNST (malignant peripheral nerve sheath tumour)

Irritated Seborrheic Keratosis (squamous eddies): 5-Minute Pathology Pearls

Ischemic fasciitis (atypical decubital fibroplasia) video

Juvenile xanthogranuloma WITHOUT Touton giant cells (JXG sans Touton)

Kaposi sarcoma, nodular/tumour stage

Kaposiform Hemangioendothelioma & Tufted Angioma

Keloid under the microscope

Keratin amyloid (NOT systemic amyloidosis/light chain AL amyloid!) video

Keratin Pearl (SCC) vs Horn Pseudocyst (SK) video

Leishmaniasis (Leishmania Infection) 5-Minute Pathology Pearls ‪Dermatology Dermatopathology video

Lepromatous Leprosy: 5-Minute Pathology Pearls Dermatology Dermatopathology video

Lichen sclerosus with epidermotropism (mimic of mycosis fungoides)

Lymphangioma (Lymphatic Malformation) short video

Macular amyloid (keratin derived amyloid - NOT systemic amyloidosis)

Masson "Tumor” (Intravascular papillary endothelial hyperplasia IPEH) pattern of organizing thrombus (video)

Masson "Tumor" (organizing thrombus & papillary endothelial hyperplasia in a vascular malformation) video

Median Raphe Cyst: 5-Minute Pathology Pearls (video)

Melanocytes vs Keratinocytes Made Easy: 5-Minute Pathology Pearls

Melanocytic Dermpath Basics: Benign Nevus 101 (video)

Metabolic/Deposition Diseases of Skin & Mimics: Board Review for Dermpath Dermatology Pathology

Melanocytic Dermpath Basics: Immunohistochemistry

Molecular Testing Basics explained in 15 minutes (video)

Molluscum "Cyst"

Monckeberg medial calcific sclerosis (blood vessel calcification - not calciphylaxis)

Mucocele of Lip (Mucous Extravasation Phenomenon): 5-Minute Pathology Pearls

Myofibroblasts vs Smooth Muscle Made Easy

Myofibroma 101 explained in 5 minutes

Myofibroma under the microscope

Myopericytoma vs Angioleiomyoma

Myrmecia Wart (verruca myrmecia type)

Necrotizing Fasciitis "Flesh Eating Bacteria" Group A Streptococcus Under the Microscope Pathology video

Nerve vs Smooth Muscle vs Dense Regular Connective Tissue (tendon fascia ligament) Histology Anatomy video

Nocardia Infection: Gram-positive, Partially Acid Fast, Aerobic, Filamentous Bacteria video

Nodular Amyloidosis (AL light chain amyloidosis in skin)

Nodular fasciitis

Nodular fasciitis 101 - tips & tricks for diagnosis

Nodular Fasciitis Tips & Tricks: 5-Minute Pathology Pearls video

Nodular fasciitis with intravascular "invasion" (video)

Normal skin histology 101 video

Onchocerciasis (Onchocercoma - tangled mass of Onchocerca worms with paired uteri & microfilariae)

Orf (ecthyma contagiosum/skin virus disease from sheep)

Palisaded Encapsulated Neuroma vs Schwannoma explained in 5 minutes

Pemphigus foliaceus (autoimmune skin blister immunobullous disease in pemphigus vulgaris family)

Perniosis/Chilblains (one cause of blue/purple fingers and toes in cold weather)

Pigmented Purpuric Dermatosis (Schamberg disease, lichen aureus, etc)

Pilonidal cyst/sinus/tract: 5-Minute Pathology Pearls (video)

Pitted Keratolysis (Corynebacterium Skin Infection of Feet): 5-Minute Pathology Pearls Dermatology video

Pityriasis Versicolor/Tinea Versicolor 101: Malassezia/Pityrosporum Fungus Skin Infection video

Polyarteritis Nodosa

Porokeratosis Ptychotropica: 5-Minute Pathology Pearls (video)

Pleomorphic fibroma (looks like skin tag but relative of spindle cell/pleomorphic lipoma)

Post-traumatic fat necrosis (encapsulated subcutaneous fat necrosis)

Pretibial myxedema (Graves disease thyroid dermopathy) (NOT scleredema or scleromyxedema)

Proliferative Myositis / Proliferative Fasciitis (an important pseudo-sarcoma all pathologists should know!) video

Pseudomyogenic hemangioendothelioma (a mimic of epithelioid sarcoma)

Random Dermpath Cases (tick mouthparts, Masson, Pinkus, Fournier gangrene, etc) video

Rash got WORSE with topical steroids? Check for fungus! (tinea incognito) Dermatology Tips (video)

Reaction to Skin Fillers (Hyaluronic acid lip filler with palisaded granuloma reaction)

Rosai Dorfman Disease (mimicking "inflammatory pseudotumor") video

Scabies poop (scybala) - a microscopic clue for scabies

Scar & biopsy site change

Scleredema (NOT pretibial myxedema or scleromyxedema)

Scleromyxedema (lichen myxedematosus) (NOT pretibial myxedema or scleromyxedema)

Sclerotic fibroma aka plywood fibroma aka storiform collagenoma (swirling collagen with cracking artifact)

Sclerotic fibroma (storiform collagenoma/plywood fibroma)

Scrotal calcinosis (calcinosis cutis of scrotum)

Seborrheic Keratosis 101 video: 5-Minute Pathology Pearls

Shingles under the microscope (Varicella Zoster Herpes virus Chickenpox VZV pathology dermatology)

Skin Histology: Acral Skin (aka glabrous skin of palm of hand & sole of foot) video

Skin Histology: Blood Vessel vs Gland vs Artifact

Skin Histology: DERMIS (the Epidermis can't live without it!) video

Skin Histology: Epidermis Layers (stratum basale, spinosum, granulosum, lucidum & corneum) video

Skin Histology: Immunohistochemistry Basics (for Dermatology Histotechnologist Dermpath Pathology) video

Skin Histology: Meissner Corpuscle (tactile corpuscle) video

Soft Tissue Pathology (epithelioid fibrous histiocytoma ALK-1, atypical FH, paraganglioma, and more) video

Solar Elastosis: 5-Minute Pathology Pearls (video)

Solar Lentigo vs Junctional Nevus (plus sun burn cells & large cell acanthoma) video

Solar purpura (bruising on arms and hands of the elderly due to sun damage)

Squamous cell carcinoma in situ (Bowen's disease) with massive pleomorphism

Steroid injection under the microscope (kenalog with giant cell reaction in hypertrophic scar)

Subepidermal calcified nodule (calcium eyelid bump in kids)

Subungual acral lentiginous melanoma in situ

Subungual crusted scabies (scabies under the fingernail)

Verrucous Hemangioma (short video)

Superficial and/or deep perivascular pattern

Superficial thrombophlebitis

Sweat glands under microscope (skin adnexa histology anatomy eccrine apocrine sebaceous hair) video

Sweet syndrome explained in 5 minutes

Syphilis: Spirochete Immunostain vs Steiner & Warthin-Starry Silver Stains 5-Minute Pathology Pearls video

Tick bite close up under microscope (tick embedded in skin with vasculitis)

Tick bite under the microscope (tick mouthparts in skin)

Tick Bite...under the microscope (tick mouthparts stuck in skin) video

Tick head & body under the microscopic (Tick Microscopic Anatomy & Histology)

Tinea capitis (dermatophyte fungus in hair follicles endothrix ectothrix patterns)

Tinea Nigra: Black Mold Skin Infection (Dematiaceous Pigmented Fungus) 5-Minute Pathology Pearls video

Tinea Versicolor/Pityriasis Versicolor (Malassezia aka Pityrosporum Skin Infection) 5-Minute Pathology Pearls video

Tinea/Dermatophyte Fungal Skin Infection: 5-Minute Pathology Pearls video

Tinea/dermatophytosis with fungal folliculitis (discussion of Majocchi granuloma & tinea incognito) video

Tonsil Actinomyces: 5-Minute Pathology Pearls video

Trichilemmal Cyst/Pilar Cyst: 5-Minute Pathology Pearls (video)

Trichoblastoma

Tuberculoid Leprosy (Hansen disease): 5-Minute Pathology Pearls Dermatology Dermatopathology video

Tuberous xanthoma

Tumid lupus erythematosus

Urticaria

Urticaria (short video)

Venous stasis vascular change

Verruca Plana (Flat Wart): 5-Minute Pathology Pearls video

Verruca Vulgaris vs Seborrheic Keratosis: 5 Minute Pathology Pearls video

Verruciform xanthoma (looks like a "wart on fire" with foamy cells in dermis)

Verrucous carcinoma (not caused by HPV)

Verrucous cyst (benign cyst with HPV infection)

Verrucous Cyst: 5-Minute Pathology Pearls (video)

Viral Infections of Skin & Mimics: Board Review for Dermpath Dermatology Pathology

VZV Varicella Zoster Herpes

Wart with cutaneous horn (verruca wart under the microscope pathology dermpath dermatology)

Warty Dyskeratoma

Wells syndrome (eosinophilic cellulitis) with flame figures

What contaminated cocaine does to skin (Levamisole Vasculopathy)

What is Botryomycosis? Hint: it's not fungus! 5-Minute Pathology Pearls Dermatology Dermpath video

Where are the Verocay bodies?! Recognizing subtle nuclear palisading in schwannoma

Xanthelasma (xanthoma of eyelid)