Seborrheic keratosis (SK) is the most common benign Benign Fibroadenoma epithelial cutaneous neoplasm. The condition consists of immature keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions. Seborrheic keratosis is the most common benign Benign Fibroadenoma skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions tumor Tumor Inflammation in middle-aged and elderly adults and presents as a sharply demarcated, exophytic Exophytic Retinoblastoma, skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesion that may be tan or black and has a “stuck-on” appearance. Pruritus Pruritus An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief. Atopic Dermatitis (Eczema) or pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways can occur if these lesions become secondarily inflamed by trauma, especially if they are within the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions folds. Genetics Genetics Genetics is the study of genes and their functions and behaviors. Basic Terms of Genetics are thought to play a role, but the pathogenesis is uncertain. The most common mutations involve two oncogenes Oncogenes Genes whose gain-of-function alterations lead to neoplastic cell transformation. They include, for example, genes for activators or stimulators of cell proliferation such as growth factors, growth factor receptors, protein kinases, signal transducers, nuclear phosphoproteins, and transcription factors. A prefix of 'v-' before oncogene symbols indicates oncogenes captured and transmitted by retroviruses; the prefix 'c-' before the gene symbol of an oncogene indicates it is the cellular homolog (proto-oncogenes) of a v-oncogene. Carcinogenesis: fibroblast growth factor Fibroblast growth factor A family of small polypeptide growth factors that share several common features including a strong affinity for heparin, and a central barrel-shaped core region of 140 amino acids that is highly homologous between family members. Although originally studied as proteins that stimulate the growth of fibroblasts this distinction is no longer a requirement for membership in the fibroblast growth factor family. X-linked Hypophosphatemic Rickets receptor Receptor Receptors are proteins located either on the surface of or within a cell that can bind to signaling molecules known as ligands (e.g., hormones) and cause some type of response within the cell. Receptors 3 (FGFR3) and PIK3CA. There is a familial predisposition to develop a high number of seborrheic keratoses. Treatment is not necessary, as this is a benign Benign Fibroadenoma condition, but cryotherapy Cryotherapy A form of therapy consisting in the local or general use of cold. The selective destruction of tissue by extreme cold or freezing is cryosurgery. Chondrosarcoma, curettage Curettage A scraping, usually of the interior of a cavity or tract, for removal of new growth or other abnormal tissue, or to obtain material for tissue diagnosis. It is performed with a curet (curette), a spoon-shaped instrument designed for that purpose. Benign Bone Tumors or electrodesiccation can be performed for discomfort or cosmetic concerns.
Last updated: 30 Mar, 2021
Seborrheic keratosis (SK) is a benign Benign Fibroadenoma skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions tumor Tumor Inflammation consisting of proliferating immature keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions.
Pigmented seborrheic keratosis of the
vulva
Vulva
The vulva is the external genitalia of the female and includes the mons pubis, labia majora, labia minora, clitoris, vestibule, vestibular bulb, and greater vestibular glands.
Vagina, Vulva, and Pelvic Floor: Anatomy:
Note the domed shape, sharp circumscription from the surrounding
skin
Skin
The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue.
Skin: Structure and Functions, horn
cysts
Cysts
Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues.
Fibrocystic Change, and the brown melanin pigment within the
epidermis
Epidermis
The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
Skin: Structure and Functions and in the adjacent
dermis
Dermis
A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands.
Skin: Structure and Functions (within
macrophages
Macrophages
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells.
Innate Immunity: Phagocytes and Antigen Presentation).
The blue line below the lesion demonstrates the “
string sign
String Sign
Hypertrophic Pyloric Stenosis” of SK seen at low-
power
Power
The probability that a test will correctly reject a false null hypothesis.
Statistical Tests and Data Representation magnification: A horizontal line can be drawn parallel to the epidermal surface underlying the lesion because the SK extends uniformly to one depth.
Low-
power
Power
The probability that a test will correctly reject a false null hypothesis.
Statistical Tests and Data Representation microphotograph of a shave
biopsy
Biopsy
Removal and pathologic examination of specimens from the living body.
Ewing Sarcoma of a hyperkeratotic seborrheic keratosis showing the superficial pink-staining keratinous material partially detached from the surface.
Note the thickened
epidermis
Epidermis
The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
Skin: Structure and Functions with anastomosing strands of proliferating basaloid cells within the
epidermis
Epidermis
The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
Skin: Structure and Functions.
Seborrheic keratosis with rough surface:
Note the typical waxy appearance, the well-circumscribed border, and the superficial stuck-on appearance.
A and B: Leser–Trélat sign in a 92-year-old woman with advanced
ovarian cancer
Ovarian cancer
Ovarian cancer is a malignant tumor arising from the ovarian tissue and is classified according to the type of tissue from which it originates. The 3 major types of ovarian cancer are epithelial ovarian carcinomas (EOCs), ovarian germ cell tumors (OGCTs), and sex cord-stromal tumors (SCSTs).
Ovarian Cancer. Multiple eruptive seborrheic keratoses had dramatically increased in size and number over the previous 2 years.
C: CT scan showing a necrotic ovarian
tumor
Tumor
Inflammation accompanied by signs of peritoneal carcinomatosis
Physical exam:
Dermoscopy:
Biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma: