Sandbox:Roukoz

Diseases		Clinical manifestations				Para-clinical findings				Additional findings
		Skin Examination
						Lab Findings			Histopathology
		Type	Color	Risk factors	Skin exam 3	Dermoscopic Findings	Areas affected	Unique features
Cutaneous squamous cell carcinoma	SCC in situ (Bowen's disease)	Well-demarcated, scaly patch or plaque	Erythematous Skin colored		Hyperkeratotic, or ulcerative lesions		Any cutaneous surface, including the head, neck, trunk, extremities, oral mucosa, shoulders, chest and back	In fair-skinned individuals, SCCs most commonly arise in sites frequently exposed to the sun In black individuals, common sites for SCC include the legs, anus, and areas of chronic inflammation or scarring	Keratinocytic dysplasia involving the full thickness of the epidermis without infiltration of atypical cells into the dermis The keratinocytes are pleomorphic with hyperchromatic nuclei, and numerous mitoses are present.	SCC in situ lesions tend to grow slowly, enlarging over the course of years
	Invasive squamous cell carcinoma	Papules Plaques Nodules	Poorly differentiated lesions are usually fleshy, soft, granulomatous papules or nodules that lack the hyperkeratosis that is often seen in well-differentiated lesions	none	Poorly differentiated tumors may have ulceration, hemorrhage, or areas of necrosis. Well-differentiated lesions usually appear as indurated or firm, hyperkeratotic	White circles, keratin, blood spots, and white structureless zones	same as above	same as above	same as above	same as above
Keratoacanthoma		Initial lesion: small pink macule Later: papular quality and eventually forms a circumscribed nodule.	The periphery of the nodule tends to be skin-colored or mildly erythematous and may have accompanying telangiectasias	Skin color Ultraviolet radiation Genetics Drug exposure (BRAF inhibitors) Trauma (surgery, laser therapy, cryotherapy or accidental trauma) Chemical carcinogens (tar, pitch, polyaromatic hydrocarbons) Human papillomavirus infection	The center of the nodule typically demonstrates a prominent keratinous core.	White circles, keratin, blood spots, and white structureless zones	Develops on sun-exposed areas of the skin. The face (especially the eyelids, nose, cheek, and lower lip), neck, hands, and arms are common sites for involvement	a history of rapid growth within weeks favors this diagnosis	Epidermal hyperplasia with large eosinophilic keratinocytes Central invagination with a keratotic core (in later stages) "Lipping" or "buttressing" of the epidermis over the peripheral rim of the central keratotic plug Sharp demarcation between the tumor and the surrounding stroma Mixed inflammatory infiltrate in the dermis	It is controversial whether keratoacanthomas represent a subtype of well-differentiated SCC or a separate entity
Merkel cell carcinoma		rapidly growing, painless, firm, nontender, shiny, flesh-colored or bluish-red, intracutaneous nodule	No more additional findings	Older patients with light skin tones	No more additional findings	Milky red areas; linear, irregular vessels; and polymorphous vessels	Starts on areas of skin exposed to the sun Most frequent locations for the primary tumor are head and neck, upper limbs and shoulder, lower limbs and hip, and trunk		Strands or nests of monotonously uniform, round, blue cells, containing large basophilic nuclei with powdery dispersed chromatin and inconspicuous nucleoli, and minimal cytoplasm Single-cell necrosis, frequent mitoses, lymphovascular invasion, perineural invasion, and epidermal involvement via pagetoid spread.	Blue-red, dome-shaped nodule
Nodular basal cell carcinoma		Pearly papule with telangiectasias	Pink or flesh-colored papule	none	No more additional findings		Typically presents on the face	May have a "rolled" border, where the periphery is more raised than the middle.		Ulceration is frequent, and the term "rodent ulcer" refers to these ulcerated nodular BCCs
Superficial basal cell carcinoma		Scaly patch	Erythematous lesion		No more additional findings				large, hyperchromatic, oval nuclei and little cytoplasm well differentiated and cells appear histologically similar to basal cells of the epidermis
Prurigo nodules		Firm, dome-shaped and itchy	ranging in size from a few millimeters to several centimeters and often symmetrically distributed	none	Nodules can be flesh-colored, erythematous, or brown/black		Extensor surfaces of the arms and legs and on the trunk Upper back, abdomen, and sacrum	Worsened by heat, sweating, or irritation from clothing	Thick, compact orthohyperkeratosis Irregular epidermal hyperplasia or pseudoepitheliomatous hyperplasia Focal parakeratosis with irregular acanthosis Diminished nerve fiber density A nonspecific dermal infiltrate containing lymphocytes, macrophages, eosinophils, and neutrophils	Nodules range in number from few to hundreds upper midback area is usually spared
Common nevus		Dome-shaped, usually nonpigmented or hypopigmented nodules with a smooth surface	Terminal hairs are often present			Comma-shaped or curved vessels Structureless skin-colored to light brown background pigmentation Residual brown globules (clods) or brown thick circles, mainly located around the hair follicles can sometimes be seen
Blue nevus		Bluish macules or papules				Structureless blue pigmentation Structureless blue and white or blue and brown on some occasions	Head and neck, Dorsal aspect of the distal extremities Sacral area
Spitz nevus	Nonpigmented Spitz nevus					coiled vessels and a white network (also called reticular depigmentation or negative network) over a pink to reddish background				benign, indolent melanocyte proliferation that most commonly develops in children, adolescents, and young adults.
	Reed-like Spitz					coiled vessels and a white network (also called reticular depigmentation or negative network) over a pink to reddish background				benign, indolent melanocyte proliferation that most commonly develops in children, adolescents, and young adults.
Solar lentigo
Lentigo Maligna
Lentigo Maligna Melanoma
Sebaceous hyperplasia
Lichen planus-like keratosis
Seborrheic keratosis
Actinic keratosis		less pigmentation, and tend to be somewhat smaller in size.	Erythema		Hyperkeratosis					painful
Nodular malignant melanoma		Lump that has been rapidly growing over the past weeks	No more additional findings	none	No more additional findings				Cells proliferate downwards through the skin (vertical growth)	Two-thirds arise in normal skin, the rest in existing moles Genetic component in some cases with a positive family history
Amelanotic melanoma		Color usually pink, purple or normal skin color	Usually have an asymmetrical shape with an irregular border		Red, nonspecific lesion with slightly elevated borders					Do not make melanin, so lesions are not pigmented

SCC in situ: Frequently, there is associated thickening of the epidermis (acanthosis), as well as hyperkeratosis and parakeratosis of the stratum corneum. In contrast to SCC in situ, actinic keratoses demonstrate only partial-thickness epidermal dysplasia.