GROWTH KINGDOM

STUART TOBIN, M.D. DIVISION OF DERMATOLOGY ASSOCIATE PROFESSOR OF SURGERY UK HEALTHCARE Growth Kingdom

 Dermatology is subdivided into two general divisions or kingdoms.  In biology there was the plant kingdom and the animal kingdom.  In dermatology there is the rash kingdom and the growth kingdom.  First algorithmic decision one needs to make is it a rash or a growth? •If it is a growth then there is an app or logical sequential pattern in determining what the diagnosis is.

•Almost every growth on the skin derives from a normal skin cell or skin structure.

•By classifying the growth into one of the limited number of skin cells or skin structures one can formulate a differential diagnosis.

•The skin is composed of the epidermis, dermis and subcutaneous fat

•Within each of these layers are individual cells and tissue units that compose each layer. The primary epidermis skin cells are:

1. Squamous Cell 2. Melanocyte 3. Basal cell •In the dermis the primary cells are histiocytes and fibroblasts

•A dense connective tissue matrix of collagen is also present in the dermis •Structures in the skin include blood vessels, nerves, the oil gland apparatus or the pilosebaceous structure which includes the oil gland and the hair follicle.

• Sweat glands usually eccrine and subcutaneous fat tissue which house larger blood vessels. • The clinician can formulate a differential diagnosis by determining which cell or structure the growth is derived from.

•Dermatologists are very sensitive to color and often use it as a means of placing growths into a differential. •If the lesion is RED or BLUE/PURPLE we think vascular

•If the lesion is some color variation of BROWN or BLACK we think of pigmented lesions

•If the lesion has a WHITE SCALE we think of lesions of squamous cell origin since the squamous cell is the only cell capable of producing keratin. •If the lesion has a skin color we think of lesions derived from some deeper structure pushing the skin outward and not affecting the epidermis.

•Once determining the cell or structural unit that the differential belongs then we utilize our other criteria in refining our diagnosis.

•These changes are the same as in making a differential with rashes •1) Morphology

•2) Secondary changes in the growth

•3) Configuartion

•4) Distribution

•5) History •Lesions are dynamic and not static like any disease process. Most growths start small evolve and grow larger.

•Remembering that the oldest part of a growth is in the center and the youngest part is in the periphery one will usually find the primary process at the edge of the lesion and less valuable secondary changes in the center. •The newest part of a lesion will most likely demonstrate the unique characteristics of the growth and clinical clues as to the diagnosis.

•This is particularly helpful in attempting to diagnose a basal cell carcinoma or squamous cell carcinoma where the center of the lesion has been ulcerated and masked. •Morphology of the lesion can also help considerably in diagnosing.

• Does the lesion have an organized pattern or does it appear disorganized?

•Does it have a characteristic shape and design? •History can be very helpful as well..

•Such temporal information as the lesion been there a long time or of short duration ? Has it changed?

• What symptoms does the patient have. Is it painful or tender? Is it asymptomatic as often in the case in cutaneous malignancies just as it is with internal malignancies. Skin cancers are a silent process. Red = Vascular Lesions

 When you see variations of red lesions, think vascular.  If the lesion presents with a bright red or strawberry or crimson color we think of more on the arterial side.  If it has some variation of purple or violet we lean towards the venous side. Differential of bright red lesions would include: Red =Vascular Lesions

 Cherry red angiomas  Cavernous Congenital angiomas  Congenital angiomas  Nevus Flammeus congenital and late occurring lesions, Nevus Flammeus Tardus  Spider Angiomas (Nevus Araneus)  Pyogenic Granulomas  Telangiectasias

Purple Vascular Lesions

 Venous Lakes  Senile Purpura  Angiokeratoma  Angiosarcoma (malignant)  Kaposi Sarcoma (malignant)

•The purpose of this introductory lecture is not to memorize all these diagnoses but rather to recognize some important landmarks or features onto which you can build your differential diagnosis.

•With vascular lesions the hallmark is some variation of red or purple color. You can now go to your resource material and look up each of the above to figure out what the most likely diagnosis is based on morphology of the lesion. Brown or Black Lesions

•IN ORDER FOR A LESION TO HAVE A DARK COLOR IT IS MOST LIKELY GOING TO BE DERIVED FROM A CELL THAT PRODUCES PIGMENT. •THE OBVIOUS CANDIDATE IS THE PIGMENT PRODUCING CELL, THE MELANOCYTE, WHICH RESIDES IN THE BASAL LAYER OF THE EPIDERMIS . Brown or Black Lesions

Melanocytic Nevus  Junctional Nevus in which melanocytes are situated only along the dermal epidermal junction. These lesions are macular or flat  Intradermal Nevus in which the preponderance of melanocytes are in the dermis and have migrated from the dermal epidermal junction. They may be macular or raised papular.  Compound Nevus which has features of both a junctional as well as a intradermal nevus.

Brown or Black Lesions

 Blue Nevus a melanocytic nevus that resides deeper in the skin imparting a dark blue color

 Lentigo or multiple Lentigines:  Macular or flat tan to brown lesions seen of sun exposed skin in older patients that have a very organized appearance.  Organized means they demonstrate symmetry, regular border, without color variation and small in diameter. Lentigo Simplex Blue Nevus Brown or Black Lesions

 Ephelids or freckles occur more commonly in type 2 skin patients with fair skin and lighter hair red heads.  Congenital Melanocytic Nevus pigmented mole like lesion present at birth  Seborrheic Keratoses: Warty and cobblestone growths that refract light and have a pasted like appearance.  While demonstrating a brown color they are of squamous cell and not of melanocyte origin.

Brown or Black Lesions

Pigmented Basal Cell Carcinoma

Melanoma  Lentigo Maligna  Superficial Spreading Malignant Melanoma  Lentigo Maligna Melanoma  Nodular Melanoma  Acralentiginous Melanoma

Squamous Cell Lesions

 Lesions of squamous cell origin are derived from the squamous cell.  Since the squamous cell is the predominant cell in the epidermis, these lesions have a tendency to take on a skin tone color.  The squamous cell is the only skin cell that produces keratin.  Keratin clinically presents as some form of scale or warty texture. Squamous Cell Lesions

 . If you see a scale or warty like texture to a lesion you can be fairly certain it belongs in the squamous cell differential.  Any growth that has the name keratosis attached to itself would be of squamous cell origin.  Any lesion that has acanthoma attached to it is also of squamous cell origin.  The squamous cell differential would include: Squamous Cell Growths

Verrucae or Warts

 Verrucae Vulgaris ( Common Warts)  Verrucae Plana (flat topped small warts)  Verrucae Plantaris (sole of the foot)  Filiform Warts (Digitate verrucae)  Condyloma Accuminata (Venereal Warts)  Mosaic Warts

Squamous Cell Leisons

 Seborrheic Keratosis

 Actinic (Solar) Keratosis ( Pre cancer lesion) a)non pigmented ak

b) pigmented ak

Squamous Cell Lesions

Squamous Cell Carcinoma  Squamous cell carcinoma in situ (Bowens Disease)  Bowenoid papulosis  Squamous cell carcinoma invasive well differentiated  Squamous cell carcinoma invasive poorly differentiated  Paget’s Disease usually of adenocarcinoma origin either mammary or extramammary in origin. Often presents as an eczematous derm around the nipple. SCC in S BP

Squamous Cell Lesions

 Keratoacanthoma a rapidly growing craterform shaped lesion with a rolled pink border

 Lichen Planus Like Keratosis a warty like growth characterized with a pink or purple like color.

LPK The Basal Cell

 LESIONS OF BASAL CELL ORIGIN

 Basal cell lesions usually have a translucent pearly quality which is manifested towards the periphery of the lesion. • Micronodular Basal Cell Carcinoma

•Ulcerating BCC

• Morphea (Scleroising) BCC • •Superficial multicentric BCC

•Pigmented BCC

Trichoepithelioma – a soloitary or multiple flesh colored papules that are benign in nature LESIONS OF FIBROBLASTIC OR HISTIOCYTIC ORIGIN

 These lesions have a scar like quality to them. Tactile feeling is one of hardness, density or compactness. They have a white to darkened color as seen with scar tissue. LESIONS OF FIBROBLASTIC OR HISTIOCYTIC ORIGIN

 Hypertrophic Scar  Keloid  Dermatofibroma or Histiocytoma  Dermatofibrosarcoma Protuberans  Soft fibroma (skin tags or polyps/achrochordon)  Mucinosis (Mucin is produced by fibroblasts)

DFS

Mucinoses Lesions of Deeper Dermal Origin

 Because these lesions involve the deeper skin tissues and usually do not involve the epidermis the overlying skin tends to appear normal. Clinically they appear as bumps under the skin. They have a tendency to be soft and compressible. •Pilar cysts 1) Epidermoid Cysts (except scalp) 2) Trichilemmal Cysts (scalp)

•Steatocystoma Multiplex

•Myxoid Cyts (variation of synovial cyst)

•Dermoid Cyst

Myxoid Cyst Dermoid Cyst LESIONS OF SEBACEOUS GLAND ORIGIN

 Because of their sebaceous gland origin these lesions have a tendency to have a waxy yellowish hue color appearance.

 The clinician should become acquainted with this particular color tendency since it’s the critical clinical feature in making the diagnosis. • Sebaceous Hyperplasia

•Sebaceous Adenoma

•Sebaceous Carcinoma

•Nevus Sebaceous of Jadassohn

Sebaceous Adenoma Seb Ca

LESIONS OF DEPOSITION

 These lesions can present with non waxy but a yellowish hue to the skin due to the deposition of cholesterol/fat like deposits in the skin.

 Xanthelasma  Xanthoma  Eruptive Xanthomas Xanthelasma in Mona Lisa Xanthelasma in a non Mona Lisa

LESIONS OF SUBCUTANEOUS ORIGIN

 The most common subcutaneous structure is the fat tissue. Consequently lesions of fat origin are the most likely encountered.

 Like cysts the overlying skin usually appear normal.

 Because these lesions originate in the fat they don’t have the prominent bulging exophytically in the skin like cysts. •Lipoma are freely movable rubbery subcutaneous nodules

•Angiolipoma usually appear identically as lipomas but are tender

LESIONS OF SWEAT GLAND ORIGIN

 Syringoma

 Eccrine Poroma

 Syringocystadenoma

 Apocrine Hydrocytstoma (often has a slight purplish hue and frequently on the face)

Syringocystadenoma Eccrine Poroma

LESIONS OF NEURAL ORIGIN

 Neurofibroma (assymptomatic and depressible and flesh colored)

 Neuroma (painful) flesh colored papule

 Neurofibrosarcoma Neuroma (clinically non visible) nfs LESIONS OF MUSCLE ORIGIN

 Leiomyoma (solitary or grouped and usually painful to touch)

SUMMARY

•Most skin growths arise from either preexisting skin cells or skin structural units.

•The color or the texture surface of the growth assists in determining the cell or structure that the growth arose from.

•Red indicates a vascular (arterial or venous) lesion

• Purple indicates a venous vascular lesion

• Brown/Black indicates a pigmented lesion Summary continued

•White scale or keratin indicates a lesion of squamous cell origin.

• Pearly shiny color is associated with the basal cell.

•Skin color growths suggest lesions of dermal or subcutaneous origin in which the overlying skin is being distorted by the underlying growth.

•Organizing your approach to growths based on the skin cells or the skin structural unit aids your thinking in making a differential diagnosis. Using your knowledge of morphology, secondary lesions, configuration, distribution and history accompanied by a good resource Atlas the physician can deduce an excellent differential and diagnosis.