Atlas of Dermatopathology

DETAILED CONTENTS
How to Use This Book vii
Preface xvii
Preface to the First Edition xix
Acknowledgments xxi
Introduction xxiii
Disorders Mostly Limited to
the Epidermis and Stratum
Corneum 1
A. Hyperkeratosis With Hypogranulosis 1
1. No Inflammation 1
Ichthyosis Vulgaris 2
B. Hyperkeratosis With Normal or Hypergranulosis 2
1. No Inflammation 3
X-Linked Ichthyosis 3
Epidermolytic Hyperkeratosis 3
Epidermodysplasia Verruciformis 5
2. Scant Inflammation 6
Lichen Amyloidosis and Macular Amyloidosis 7
C. Hyperkeratosis With Parakeratosis 8
1. Scant or No Inflammation 8
Dermatophytosis 8
Granular Parakeratosis 9
D. Localized or Diffuse Hyperpigmentations 10
1. No Inflammation 10
Mucosal Melanotic Macules (Mucosal Lentigines) 11
Ephelids (Freckles) 12
2. Scant Inflammation 13
Pityriasis (Tinea) Versicolor 13
E. Localized or Diffuse Hypopigmentations 14
1. With or Without Slight Inflammation 14
Vitiligo 14
References 16
Localized Superficial
Epidermal or Melanocytic
Proliferations 17
A. Localized Irregular Thickening of the Epidermis 18
1. Localized Epidermal Proliferations 18
I
II
Actinic Keratosis 18
Eccrine Poroma 20
Squamous Cell Carcinoma In Situ and Bowen Disease 20
Bowenoid Papulosis 22
Clear Cell Squamous Cell Carcinoma In Situ 23
Clear Cell Acanthoma 23
2. Superficial Melanocytic Proliferations 26
Superficial Melanocytic Nevi and Melanomas 26
Pigmented Spindle Cell Nevus 27
Acral Melanoma 27
B. Localized Lesions With Thinning
of the Epidermis 30
1. With Melanocytic Proliferation 30
Lentigo Maligna Melanoma, In Situ or
Microinvasive (High CSD) 30
Recurrent (“Persistent”) Nevus, Lentiginous Patterns 31
Superficial Atypical Melanocytic Proliferations of
Uncertain Significance (SAMPUS and IAMPUS),
Lentiginous Patterns 33
2. Without Melanocytic Proliferation 34
Atrophic Actinic Keratosis 34
Porokeratosis 34
C. Localized Lesions With Elongated Rete Ridges 36
1. With Melanocytic Proliferation 36
Actinic Lentigo 36
Lentigo Simplex 37
Lentiginous Junctional Nevus 37
Nevus Spilus 38
Junctional or Superficial Compound Dysplastic Nevi 40
Nevoid Lentigo Maligna 42
2. Without Melanocytic Proliferation 44
Epidermal Nevus 44
Seborrheic Keratoses 45
Acanthosis Nigricans 45
D. Localized Lesions With Pagetoid
Epithelial Proliferation 47
1. Keratinocytic Proliferations 47
Pagetoid Squamous Cell Carcinoma In Situ (Bowen Disease) 47
Clonal Seborrheic Keratosis 47
2. Melanocytic Proliferation 48
Melanoma In Situ or Microinvasive, Superficial
Spreading Type 48
Recurrent Nevus (Pseudomelanoma), Pagetoid Pattern 51
Junctional Spitz Tumor (Nevus) With Pagetoid
Proliferation 51
Superficial/Intraepidermal Atypical Melanocytic
Proliferations of Uncertain Significance
(SAMPUS/IAMPUS), Pagetoid Patterns 51x Detailed Contents
3. Glandular Epithelial Proliferations 54
Paget Disease 54
4. Lymphoid Proliferations 55
Pagetoid Reticulosis (Woringer–Kolopp Disease) 55
E. Localized Papillomatous Epithelial Lesions 55
1. With Viral Cytopathic Effects 55
Verruca Vulgaris 55
Verruca Plana 55
Deep Palmoplantar Warts (Myrmecia) 57
Condyloma Acuminatum 57
Molluscum Contagiosum 58
Parapox Virus Infections (Milkers’ Nodules, Orf) 60
2. No Viral Cytopathic Effect 61
Seborrheic Keratosis 61
Dowling–Degos Disease 61
Confluent and Reticulated Papillomatosis
(Gougerot–Carteaud) 62
Verrucous Melanoma 64
F . Irregular Proliferations Extending
Into the Superficial Dermis 65
1. Squamous Differentiation 65
Inverted Follicular Keratosis 65
2. Basaloid Differentiation 67
Basal Cell Carcinoma 67
G. Superficial Polypoid Lesions 69
1. Melanocytic Lesions 69
Polypoid Dermal and Compound Nevi 70
2. Spindle Cell and Stromal Lesions 70
Neurofibroma 71
Fibroepithelial Polyp 71
References 72
Disorders of the Superficial
Cutaneous Reactive Unit 77
A. Superficial Perivascular Dermatitis 79
1. Superficial Perivascular Dermatitis, Mostly Lymphocytes 79
Viral Exanthem 79
Pityriasis Versicolor 81
Lupus Erythematosus, Acute 81
Small Plaque Parapsoriasis (Guttate Parapsoriasis) 83
1a. Superficial Perivascular Dermatitis With Eosinophils 84
Morbilliform Drug Eruption 84
Urticaria 84
Urticarial Bullous Pemphigoid 87
1b. Superficial Perivascular Dermatitis With Neutrophils 87
Erysipelas 87
Erysipelas/Cellulitis 87
1c. Superficial Perivascular Dermatitis With Plasma Cells 88
Secondary Syphilis 88
Kaposi Sarcoma, Patch Stage 90
III
1d . S uper ficial P eriv asc ular D erma titis , W ith
Extravasated Red Cells 92
Pityriasis Rosea 92
Pityriasis Lichenoides 93
Pigmented Purpuric Dermatosis 95
1e. Superficial Perivascular Dermatitis, Melanophages
Prominent 97
Postinflammatory Hyperpigmentation 97
2. Superficial Perivascular Dermatitis, Mast
Cells Predominant 98
Urticaria Pigmentosa 98
B. Superficial Dermatitis With Spongiosis
(Spongiotic Dermatitis) 100
Acute Spongiotic Dermatitis 100
Subacute Spongiotic Dermatitis 100
Chronic Spongiotic Dermatitis 100
1. Spongiotic Dermatitis, Lymphocytes Predominant 101
Nummular Dermatitis (Eczema) 101
Meyerson Nevus 101
1a. S pongiotic D erma titis , W ith E osinophils 103
Allergic Contact Dermatitis 103
Allergic Contact Dermatitis 104
1b. Spongiotic Dermatitis, With Plasma Cells 106
1c . S pongiotic D erma titis , W ith N eutr ophils 106
Seborrheic Dermatitis 106
C. S uper ficial Derma titis W ith Epidermal
Atrophy (Atrophic Dermatitis) 107
1. Atrophic Dermatitis, Scant Inflammatory Infiltrates 107
Aged Skin 108
Chronic Radiation Dermatitis 108
2. Atrophic Dermatitis, Lymphocytes Predominant 108
Poikiloderma Atrophicans Vasculare 108
Dermatomyositis 110
3. Atrophic Dermatitis With Papillary Dermal Sclerosis 111
Lichen Sclerosus Et Atrophicus 111
D. Superficial Dermatitis With Psoriasiform Proliferation
(Psoriasiform Dermatitis) 113
1. Psoriasiform Dermatitis, Mostly Lymphocytes 113
Pityriasis Rubra Pilaris 113
Mycosis Fungoides, Patch-Plaque Stage 113
Parapsoriasis 117
1a. P soriasif orm D erma titis , W ith Plasma C ells 118
Lichen Simplex Chronicus (See also IIIE) 118
1b . P soriasif orm D erma titis , W ith E osinophils 120
Chronic Spongiotic Dermatitis 120
2. Psoriasiform Dermatitis, Neutrophils Prominent
(Neutrophilic/Pustular Psoriasiform Dermatitis) 120
Psoriasis Vulgaris 120
Guttate Psoriasis 121
3. Psoriasiform Dermatitis, With Epidermal Pallor
and Necrosis (“Nutritional Pattern” Dermatoses) 123
Necrolytic Migratory Erythema (Glucagonoma Syndrome) 124
Necrolytic Acral Erythema 125
Pellagra 126Detailed Contents xi
E. Superficial Dermatitis With Irregular Epidermal
Proliferation (“Hypertrophic Dermatitis”) 128
1. Hypertrophic Dermatitis, Lymphocytes Predominant 128
Prurigo Nodularis 128
1a. Irregular Epidermal Proliferation, Plasma
Cells Present 129
Actinic Keratosis (See also IIA1) 129
2. Irregular Epidermal Proliferation,
Neutrophils Prominent 130
Keratoacanthoma (See also VIB1) 130
Deep Fungus Infection (See also VD1) 130
3. Irregular Epidermal Proliferation, Above A Neoplasm 130
Verrucous Melanoma (See also VIB3) 130
F . Superficial Dermatitis With Lichenoid
Infiltrates (Lichenoid Dermatitis) 131
1. Lichenoid Dermatitis, Lymphocytes Exclusively 131
Lichen Planus 131
Graft-Versus-Host Disease 133
Mycosis Fungoides, Patch/Plaque Stage 134
2. Lichenoid Dermatitis, Lymphocytes Predominant 135
Lichen Planus–Like Keratosis (Benign
Lichenoid Keratosis) 135
2a. Lichenoid Dermatitis, Eosinophils Present 136
Lichenoid Drug Eruptions 136
2b. Lichenoid Dermatitis, Plasma Cells Present 138
Lichenoid Actinic Keratosis 138
Secondary Syphilis 138
2c. Lichenoid Dermatitis, With Melanophages 139
3. Lichenoid Dermatitis, Histiocytes Predominant 140
Lichen Nitidus 140
4. Lichenoid Dermatitis, Mast Cells Predominant 141
Urticaria Pigmentosa, Lichenoid Examples 141
5. Lichenoid Dermatitis With Dermal Fibroplasia 142
Mycosis Fungoides, Patch Stage 142
G. Superficial Vasculitis and Vasculopathies 143
1. Neutrophilic Vasculitis 143
Cutaneous Necrotizing (Leukocytoclastic) Vasculitis 144
Septic Vasculitis (Gonococcemia) 145
2. Mixed Cell and Granulomatous Vasculitis 146
Granuloma Faciale 146
3. Vasculopathies With Lymphocytic Inflammation 147
Pigmented Purpuric Dermatoses 148
4. Vasculopathies With Scant Inflammation 149
Stasis Dermatitis 149
Stasis Dermatitis 149
5. Thrombotic, Embolic and Other Microangiopathies 150
Lupus Anticoagulant and Antiocardiolipin Syndromes 150
Cryoglobulinemia 151
H. Superficial Dermatitis With Interface
Vacuoles (Interface Dermatitis) 152
1. Vacuolar Dermatitis, Apoptotic/Necrotic Cells Prominent 152
Erythema Multiforme 152
Fixed Drug Eruption 155
Graft-Versus-Host Disease, Acute 155
2. Vacuolar Dermatitis, Apoptotic Cells Usually Absent 156
Dermatomyositis 156
3. Vacuolar Dermatitis, Variable Apoptosis 157
Subacute Cutaneous Lupus Erythematosus 157
4. Vacuolar Dermatitis, Basement Membranes Thickened 159
Discoid Lupus Erythematosus 159
References 161
Acantholytic, Vesicular, and
Pustular Disorders 165
A. Subcorneal or Intracorneal Separation 166
1. Sub/Intracorneal Separation, Scant Inflammatory Cells 166
Pemphigus Foliaceus 166
2. Sub/Intracorneal Separation, Neutrophils Prominent 167
Impetigo Contagiosa 167
Staphylococcal Scalded Skin Syndrome 168
Folliculitis With Subcorneal Pustule Formation 169
Acute Generalized Exanthematous Pustulosis 169
Pustular Psoriasis and Palmoplantar Pustulosis 170
3. Sub/Intracorneal Separation, Eosinophils Predominant 173
Erythema Toxicum Neonatorum 173
Scabies With Eosinophilic Pustulosis 173
B. Intraspinous Keratinocyte Separation, Spongiotic 174
1. Intraspinous Spongiosis, Scant Inflammatory Cells 174
Friction Blister 174
2. Intraspinous Spongiosis, Lymphocytes Predominant 175
Dyshidrotic Dermatitis/Eczema (Pompholyx) 176
2a. Intraspinous Spongiosis, Eosinophils Present 176
Acute Contact Dermatitis 177
Bullous Pemphigoid, Urticarial Phase 178
Incontinentia Pigmenti 178
3. Intraspinous Spongiosis, Neutrophils Predominant 180
Dermatophytosis 180
C. Intraspinous Keratinocyte Separation,
Acantholytic 181
1. Intraspinous Acantholysis, Scant Inflammatory Cells 181
Familial Benign Pemphigus (Hailey–Hailey Disease) 181
Transient Acantholytic Dermatosis (Grover Disease) 182
2. Intraspinous Acantholysis, Predominant Lymphocytes 184
Herpes Simplex 184
Varicella-Zoster Infection 187
Toxic Epidermal Necrolysis, Stevens–Johnson
Syndrome, and Erythema Multiforme
With Intraepidermal Vesiculation 187
Paraneoplastic Pemphigus 188
2a. Intraspinous Acantholysis, Eosinophils Present 190
Pemphigus Vegetans 190
3. Intraspinous Separation, Neutrophils or
Mixed Cell types 191
IgA Pemphigus 191
IVxii Detailed Contents
D. Suprabasal Keratinocyte Separation 192
1. Suprabasal Vesicles, Scant Inflammatory Cells 192
Keratosis Follicularis (Darier Disease) 192
Warty Dyskeratoma 194
2. Suprabasal Separation, Lymphocytes and Plasma Cells 195
Acantholytic Actinic Keratosis 195
3. Suprabasal Vesicles, Lymphocytes and Eosinophils 195
Pemphigus Vulgaris 195
E . S ubepidermal V esic ular Derma titis 198
1. Subepidermal Vesicles, Scant /No Inflammation 198
Porphyria Cutanea T arda and Other Porphyrias 198
2. Subepidermal Vesicles, Lymphocytes Predominant 200
Bullous Lichen Planus 200
Polymorphous (Polymorphic) Light Eruption 201
Bullous Dermatophytosis 201
Bullous Lichen Sclerosus et Atrophicus 203
3. Subepidermal Vesicles, Eosinophils Prominent 204
Bullous Pemphigoid 204
Bullous Drug Eruption 204
Pemphigoid Gestationis (Herpes Gestationis) 204
4. Subepidermal Vesicles, Neutrophils Prominent 208
Dermatitis Herpetiformis (Duhring Disease) 208
Linear IgA Bullous Dermatosis 209
Bullous Lupus Erythematosus 210
Epidermolysis Bullosa Acquisita 211
5. Subepidermal Vesicles, Mast Cells Prominent 213
Bullous Mastocytosis 213
References 214
Perivascular, Diffuse, and
Granulomatous Infiltrates
of the Reticular Dermis 217
A. Superficial and Deep Perivascular
Infiltrates Without Vasculitis 219
1. Perivascular Infiltrates, Lymphocytes Predominant 219
Erythema Annulare Centrifugum 219
Erythema Chronicum Migrans 219
Tumid Lupus Erythematosus 219
2. Perivascular Infiltrates, Neutrophils Predominant 222
Cellulitis 222
3. Perivascular Infiltrates, Lymphocytes and Eosinophils 223
Papular Urticaria 223
Urticaria 223
Pruritic Urticarial Papules and Plaques of Pregnancy 224
4. Perivascular Infiltrates, With Plasma Cells 226
Secondary Syphilis 226
Tertiary Syphilis 228
Morphea (See Description in VF) 228
5. Perivascular Infiltrates, Mixed Cell Types 230
Erythema Chronicum Migrans 230
V
B. Vasculitis and Vasculopathies 231
1. Vascular Damage, Scant Inflammatory Cells 231
Degos Syndrome 231
2. Vasculitis, Lymphocytes Predominant 232
Pernio 232
Pityriasis Lichenoides 232
Cytomegalovirus Infection 235
Erythema Chronicum Migrans 235
3. Vasculitis, Neutrophils Prominent 236
Polyarteritis Nodosa and Microscopic Polyangiitis 236
Neutrophilic Small-Vessel Vasculitis
(Leukocytoclastic Vasculitis) 237
Erythema Elevatum Diutinum 239
4. Vasculitis, Mixed Cell Types and/or Granulomas 240
Eosinophilic Granulomatosis With Polyangiitis 240
Papulonecrotic Tuberculid 240
5. Thrombotic and Other Microangiopathies 242
Calciphylaxis 242
Livedo Reticularis 242
C. Diffuse Infiltrates of the Reticular Dermis 243
1. Diffuse Infiltrates, Lymphocytes Predominant 243
Jessner Lymphocytic Infiltration of the Skin 243
Leukemia Cutis 245
2. Diffuse Infiltrates, Neutrophils Predominant 246
Acute Febrile Neutrophilic Dermatosis (Sweet Syndrome) 246
Neutrophilic Dermatosis of the Dorsal Hands 247
Erysipelas 247
3. Diffuse Infiltrates, “Histiocytoid” Cells Predominant 249
Lepromatous Leprosy 249
Langerhans Cell Histiocytosis (Histiocytosis X) 251
Xanthelasma 253
4. Diffuse Infiltrates, Plasma Cells Prominent 253
Secondary Syphilis 253
5. Diffuse Infiltrates, Mast Cells Predominant 254
Urticaria Pigmentosa 254
6. Diffuse Infiltrates, Eosinophils Predominant 255
Eosinophilic Cellulitis (Wells Syndrome) 255
Tick Bite 257
7. Diffuse Infiltrates, Mixed Cell Types 258
Cutaneous Leishmaniasis 258
8. Diffuse Infiltrates, Pigment Cells 260
Nevi of Ota and Ito and Dermal Melanocyte Hamartoma 260
9. Diffuse Infiltrates, Extensive Necrosis 261
Gangrenous Ischemic Necrosis 261
D. Diffuse or Nodular Infiltrates of the Reticular
Dermis With Epidermal Proliferation 262
1. Epidermal Proliferation With Mixed Cellular Infiltrates 262
North American Blastomycosis 262
Deep Fungal Infections—General 264
E. Nodular Inflammatory Infiltrates of the Reticular
Dermis—Granulomas, Abscesses, and Ulcers 264
1. Epithelioid Cell Granulomas Without Necrosis 264
Sarcoidosis 265
Lupus Vulgaris 266Detailed Contents xiii
2. Epithelioid Cell Granulomas With Necrosis 267
Tuberculosis 267
Tuberculoid Leprosy 269
Lupus Miliaris Disseminatus Facei 269
3. Palisading Granulomas 270
Granuloma Annulare 270
Necrobiosis Lipoidica 272
Necrobiotic Xanthogranuloma With Paraproteinemia 272
Rheumatoid Nodules 272
Palisaded Neutrophilic and Granulomatous Dermatitis 274
4. Mixed Cell Granulomas 279
Foreign-Body Reactions 279
5. Inflammatory Nodules With Prominent Eosinophils 280
Angiolymphoid Hyperplasia With Eosinophilia 280
Epithelioid Hemangioma 280
Kimura Disease 280
Scabetic Nodule 281
6. Inflammatory Nodules With Mixed Cell Types 283
Sporotrichosis 283
Atypical Mycobacteria 283
7. Inflammatory Nodules With Necrosis and
Neutrophils (Abscesses) 286
Botryomycosis 287
Chromoblastomycosis 288
8. Inflammatory Nodules With Prominent Necrosis 288
Aspergillosis 288
9. Chronic Ulcers and Sinuses Involving the
Reticular Dermis 290
Chancroid 290
Pyoderma Gangrenosum 291
Chondrodermatitis Nodularis Helicis 293
F . Dermal Matrix Fiber Disorders 293
1. Fiber Disorders, Collagen Increased 293
Scleroderma 293
Radiation Dermatitis 294
Nephrogenic Systemic Fibrosis 296
Regressing Melanoma 298
Superficial Scar (e.g., Biopsy Site Reaction) 300
2. Fiber Disorders, Collagen Reduced 300
Focal Dermal Hypoplasia (Goltz Syndrome) 300
3. Fiber Disorders, Elastin Increased or Prominent 302
Pseudoxanthoma Elasticum 302
4. Fiber Disorders, Elastin Reduced 304
Anetoderma (Macular Atrophy) 304
5. Fiber Disorders, Perforating 304
Elastosis Perforans Serpiginosa 304
Reactive Perforating Collagenosis 305
Perforating Folliculitis 305
G. Deposition of Material in the Dermis 307
1. Increased Normal Nonfibrous Matrix Constituents 307
Digital Mucous Cysts and Cutaneous Focal Mucinosis 307
Mucinosis in Lupus Erythematosus 307
Mucinoses 307
Pretibial Myxedema 308
Scleredema 309
Lichen Myxedematosus and Scleromyxedema 309
2. Increased Material Not Normally Present in the Dermis 311
Gout 311
Oxalosis 313
Colloid Milium 313
Idiopathic Calcinosis Cutis 313
Cryoglobulinemia 316
Keratin Granuloma 316
Suture Granuloma 317
Minocycline Pigmentation 317
3. Parasitic Infestations of the Dermis and/or Subcutis 318
Cutaneous Larva Migrans 318
References 319
Tumors and Cysts of the
Dermis and Subcutis 323
A. Small and Intermediate Cell Tumors 325
1. Tumors of Lymphocytes or Hemopoietic Cells 325
Cutaneous B-Cell Follicle Center Lymphoma 325
Cutaneous Diffuse B-Cell Lymphoma 327
Primary Cutaneous Marginal Zone (MALT) Lymphoma 327
Cutaneous T-Cell Lymphoma, Tumor Stage 327
2. Tumors of Lymphocytes and Mixed Cell Types 330
B-Cell Cutaneous Lymphoid Hyperplasia (B-CLH,
Pseudolymphoma, Lymphocytoma Cutis) 330
3. Tumors of Plasma Cells 331
Cutaneous Plasmacytoma and Multiple Myeloma (MM) 331
4. Small Round Cell Tumors 332
Cutaneous Small Cell Undifferentiated Carcinoma
(Merkel Cell Tumor) 333
Metastatic Small Cell Carcinoma 333
B. Large Polygonal and Round Cell Tumors 335
1. Squamous Cell Tumors 335
Squamous Cell Carcinoma 335
Keratoacanthoma 336
Inverted Follicular Keratosis 337
Pseudoepitheliomatous Hyperplasia (PEH) 339
Proliferating Trichilemmal Cyst (Pilar Tumor) 341
Prurigo Nodularis 342
2. Adenocarcinomas 343
Metastatic Adenocarcinoma 343
Metastatic Mammary Ductal Carcinoma 344
Mammary Carcinoma, “Inflammatory” Type 344
3. Melanocytic Tumors 346
3a. Melanocytic Lesions With Little or No Cytologic Atypia 346
Melanocytic Nevi, Acquired and Congenital Types 346
Acquired Nevi, Compound and Dermal 347
Balloon Cell Nevus 348
Halo Nevus 348
Acral Nevus 350
Congenital Nevus 350
Blue Nevus 350
Cellular Blue Nevus 350
VIxiv Detailed Contents
3b. Melanocytic Lesions With Cytologic Atypia 354
Deep Penetrating Nevus 354
Spitz Tumor/Nevus 354
Nodular Melanoma 356
Superficial Spreading Melanoma (Tumorigenic) 358
Nevoid Melanoma 359
Metastatic Malignant Melanoma 359
Metastatic Malignant Melanoma, Satellite Lesion 361
Epidermotropic Metastatic Melanoma 361
Pigmented Epithelioid Melanocytoma (PEM)/
Epithelioid Blue Nevus 362
Melanocytic Tumor of Uncertain Malignant Potential 363
4. Eccrine Tumors 366
4a. Circumscribed, Symmetrical Eccrine Tumors 366
Eccrine Spiradenoma 366
Cylindroma 368
Poroma 369
Syringoma 369
Nodular Hidradenoma 370
Clear Cell Syringoma 372
Mixed Tumor (Chondroid Syringoma) 372
4b. Infiltrative, Asymmetrical Eccrine Tumors 373
Microcystic Adnexal Carcinoma 373
Mucinous Carcinoma (Mucinous Eccrine Carcinoma) 374
Digital Papillary Adenocarcinoma 374
5. Apocrine Tumors 376
Tubular Apocrine Adenoma 376
Syringocystadenoma Papilliferum 376
6. Pilar Tumors 379
Trichoepithelioma 379
Desmoplastic Trichoepithelioma 380
Dilated Pore of Winer 381
Pilar Sheath Acanthoma 381
Trichilemmoma 382
Trichofolliculoma 382
Fibrofolliculoma/Trichodiscoma 382
Trichoadenoma 382
Pilomatricoma 385
Trichoblastoma 385
7. Sebaceous Tumors 387
Sebaceous Adenoma and Sebaceous
Epithelioma (Sebaceoma) 387
Sebaceous Hyperplasia 388
Nevus Sebaceus of Jadassohn 389
Sebaceous Epithelioma 389
Sebaceous Carcinoma 389
8. “Histiocytoid” and Miscellaneous Clear Cell Tumors 391
Xanthomas and Xanthelasma 391
Xanthelasma 391
Eruptive Xanthoma 391
Verruciform Xanthoma 391
Juvenile Xanthogranuloma (JXG) 394
Reticulohistiocytosis 395
Metastatic Renal Cell Carcinoma 395
9. Tumors of Large Hematolymphoid Cells 397
Cutaneous CD30+ (Ki-1+) Anaplastic
Large Cell Lymphoma (ALCL) 397
Lymphomatoid Papulosis 398
Leukemia Cutis 399
Primary Cutaneous Diffuse Large
B-Cell Lymphoma, Leg Type 401
10. Mast C ell T umors 403
Urticaria Pigmentosa, Nodular Lesions (See also IIIA.2) 403
11. Tumors With Prominent Necrosis 404
Epithelioid Sarcoma 404
12. Miscellaneous and Undifferentiated Epithelial Tumors 406
Granular Cell Tumor 406
Cellular Neurothekeoma 406
Metastatic Malignant Melanoma 408
C. Spindle Cell, Pleomorphic and Connective
Tissue Tumors 409
1. Fibrohistiocytic Spindle Cell Tumors 409
1a. Fibrohistiocytic Tumors With Minimal or No Atypia 409
Dermatofibroma 409
Cellular Dermatofibroma 411
Sclerosing/Angiomatoid Spitz Nevus
(Desmoplastic Spitz Nevus) 411
Dermatofibrosarcoma Protuberans 411
Fibrous Papule (Angiofibroma) 414
Recurrent Infantile Digital Fibromatosis 414
Keloid 414
Acquired Digital Fibrokeratoma 414
Tenosynovial Giant Cell Tumor (Giant Cell
Tumor of Tendon Sheath) 416
Nodular Fasciitis 417
1b. Fibrohistiocytic Tumors With High-Grade Atypia 418
Atypical Fibroxanthoma 418
Malignant Fibrous Histiocytoma (Pleomorphic Dermal
Sarcoma) 419
Dermatofibrosarcoma Protuberans With
Sarcomatoid Change 420
1c. Lesions With Myxoid Changes 421
Mucocele 421
Digital Mucous Cyst 421
Cutaneous Myxoma 421
2. Schwannian/Neural Spindle Cell Tumors 423
Neurofibromas 423
Neurofibromatosis 423
Schwannoma (Neurilemmoma) 423
Palisaded Encapsulated Neuroma 425
Accessory Digit 427
3. Spindle Cell Tumors of Muscle 429
Leiomyomas 429
Smooth Muscle Hamartoma 429
Leiomyosarcoma 429
4. Melanocytic Spindle Cell Tumors 433
Desmoplastic Melanoma 433Detailed Contents xv
5. Tumors and Proliferations of Angiogenic Cells 435
Pyogenic Granuloma (Lobular Capillary Hemangioma) 435
Intravascular Papillary Endothelial Hyperplasia
(Masson’s Hemangioendotheliome
Vegetant Intravasculaire) 436
Stasis Dermatitis With Vascular Proliferation
(Acroangiodermatitis, Pseudo-Kaposi Sarcoma) 437
Kaposi Sarcoma 437
Diffuse Dermal Angiomatosis 439
Cutaneous Angiosarcoma 441
Cutaneous Epithelioid Angiomatous Nodule/
Epithelioid Hemangioendothelioma 443
T argetoid Hemosiderotic Hemangioma
(Hobnail Hemangioma) 443
Angiokeratoma 445
Arteriovenous Hemangioma 445
Cavernous Hemangioma 445
Cherry Hemangioma 447
Microvenular Hemangioma 447
Cutaneous Lymphangioma 447
Venous Lake 447
Glomangioma 447
Glomus Tumor 447
6. Tumors of Adipose Tissue 451
Nevus Lipomatosus Superficialis 451
Lipoma 451
Angiolipoma 451
Spindle Cell Lipoma 452
Pleomorphic Lipoma 454
Liposarcoma 454
7. Tumors of Cartilaginous Tissue 455
8. Tumors of Osseous Tissue 455
Albright’s Hereditary Osteodystrophy and
Osteoma Cutis 455
D. Cysts of the Dermis and Subcutis 456
1. Pilar Differentiation 456
Epidermal or Infundibular Cyst 456
Trichilemmal (Pilar) Cyst 457
Steatocystoma 457
Vellus Hair Cyst 457
2. Eccrine and Similar Differentiation 459
Eccrine Hidrocystoma 459
Median Raphe Cyst 460
Bronchogenic Cyst 460
Cutaneous Endometriosis 460
3. Apocrine Differentiation 462
Apocrine Hidrocystoma 462
Hidradenoma Papilliferum 462
References 464
Inflammatory and
Other Disorders of Skin
Appendages 469
A. Pathology Involving Hair Follicles 470
1. Scant Inflammation 470
Androgenetic Alopecia 470
Trichotillomania 470
Telogen Effluvium 474
Keratosis Pilaris 475
Scurvy 475
2. Lymphocytes Predominant 476
Alopecia Areata 476
Lichen Planopilaris 479
Central Centrifugal Cicatricial Alopecia 480
Discoid Lupus Erythematosus of the Scalp 480
Follicular Mucinosis and Alopecia Mucinosa 480
Rosacea 485
3. With Prominent Eosinophils 487
Eosinophilic Pustular Folliculitis 487
4. Neutrophils Prominent 488
Acute Deep Folliculitis (Furuncle) 488
Tinea Capitis 488
Majocchi Granuloma 488
Herpes Simplex Viral Folliculitis 489
5. Plasma Cells Prominent 491
Folliculitis (Acne) Keloidalis Nuchae 491
Tinea Capitis 492
6. Fibrosing and Suppurative Follicular Disorders 493
Follicular Occlusion Triad (Hidradenitis Suppurativa,
Acne Conglobata, and Perifolliculitis Capitis
Abscedens et Suffodiens) 493
Hidradenitis Suppurativa 493
Dissecting Cellulitis of the Scalp 495
Folliculitis Decalvans 495
B. Pathology Involving Sweat Glands 497
1. Scant Inflammation 497
Eccrine Nevus 498
2. Lymphocytes Predominant 498
Lichen Striatus 498
2a. With Plasma Cells 499
Lupus Erythematosus 499
2b . W ith E osinophils 499
Arthropod Assault Reaction 499
2c. Neutrophils Predominant 500
Neutrophilic Eccrine Hidradenitis 500
Idiopathic Recurrent Palmoplantar Hidradenitis 500
VIIxvi Detailed Contents
C. Pathology Involving Nerves 502
1. Lymphocytic Infiltrates 502
2. Mixed Inflammatory Infiltrates 503
Nerve Involvement in Leprosy 503
Erythema Chronicum Migrans With Nerve Involvement 503
Arthropod Bite Reaction With Nerve Involvement 503
3. Neoplastic Infiltrates 504
Neurotropic Melanoma 504
D. Pathology of the Nails 505
1. Lymphocytic Infiltrates 505
Acral Lentiginous Melanoma 505
2. Lymphocytes With Neutrophils 506
Onychomycosis 506
3. Vesiculobullous Diseases 507
Darier Disease 507
4. Parasitic Infestations 508
Scabies 508
References 508
Disorders of the
Subcutis 511
A. Subcutaneous Vasculitis and Vasculopathy
(Septal or Lobular) 512
1. Neutrophilic Vasculitis 512
Cutaneous/Subcutaneous Polyarteritis Nodosa
(See also Section VB3 and T able VIII.1) 512
2. Lymphocytic “Vasculitis” 513
3. Granulomatous Vasculitis 513
Erythema Induratum (Nodular Vasculitis) 513
B. Septal Panniculitis Without Vasculitis 515
1. Septal Panniculitis, Lymphocytes and Mixed Infiltrates 515
Erythema Nodosum 515
2. Septal Panniculitis, Granulomatous 517
Subcutaneous Granuloma Annulare 517
3. Septal Panniculitis, Sclerotic 519
Scleroderma and Morphea 519
C. Lobular Panniculitis Without Vasculitis 520
1. Lobular Panniculitis, Lymphocytes Predominant 520
Lupus Erythematosus Panniculitis 520
VIII
2. Lobular Panniculitis, Lymphocytes and
Plasma Cells 522
3. Lobular Panniculitis, Neutrophilic 522
4. Lobular Panniculitis, Eosinophils Prominent 522
5. Lobular Panniculitis, Histiocytes Prominent 522
Cytophagic Histiocytic Panniculitis 522
6. Lobular Panniculitis, Mixed With Foam Cells 524
Relapsing Febrile Nodular Nonsuppurative Panniculitis 524
7. Lobular Panniculitis, Granulomatous 526
Subcutaneous Sarcoidosis 526
8. Lobular Panniculitis, Crystal Deposits, Calcifications 526
Subcutaneous Fat Necrosis of the Newborn 526
Calcifying Panniculitis (Calciphylaxis) 528
9. Lobular Panniculitis, Necrosis Prominent 529
Subcutaneous Nodular Fat Necrosis in Pancreatic
Disease 529
10. Lobular Panniculitis, Embryonic Fat Pattern 531
Localized Lipoatrophy and Lipodystrophy 531
11. Lobular Panniculitis, Lipomembranous 532
Lipomembranous Change or Lipomembranous
Panniculitis 532
D. Mixed Lobular and Septal Panniculitis 533
1. With Hemorrhage or Sclerosis 533
Panniculitis due to Physical or Chemical Agents 533
2. With Many Neutrophils 534
Necrotizing Fasciitis 534
Alpha-1-Antitrypsin Deficiency–Associated Panniculitis 535
3. With Many Eosinophils 536
Eosinophilic Fasciitis (Shulman Syndrome) 536
4. With Many Lymphocytes 538
Subcutaneous Panniculitis-Like T-Cell Lymphoma 538
5. With Cytophagic Histiocytes 539
Sinus Histiocytosis With Massive Lymphadenopathy
(SHML, Rosai–Dorfman) 539
6. With Granulomas 540
Mycobacterial Panniculitis 540
Erythema Nodosum Leprosum (Type 2 Leprosy Reaction) 541
E. Subcutaneous Abscesses 543
1. With Neutrophils 543
Phaeohyphomycotic Cyst 543
References 544
Index 547