Presentation includes telangiectasia, acanthosis, and hyperkeratosis.

Presentation can be solitary or systemic.

Cherry angiomas are made up of clusters of capillaries at the surface of the skin, forming a small round dome ("papule") , which may be flat topped . They range in colour from bright red to purple. When they first develop, they may be only a tenth of a millimeter in diameter and almost flat, appearing as small red dots. However, they then usually grow to about one or two millimeters across, and sometimes to a centimeter or more in diameter . As they grow larger, they tend to expand in thickness, and may take on the raised and rounded shape of a dome. Multiple adjoining angiomas are said to form a "polypoid angioma". Because the blood vessels comprising an angioma are so close to the skin's surface, cherry angiomas may bleed profusely if they are injured.

One study found that the majority of capillaries in cherry hemangiomas are fenestrated because of staining for carbonic anhydrase activity.

Until recently, nodular fasciitis have been considered a reactive process of uncertain cause. However, recent findings indicate that nodular fasciitis is a self-limited clonal neoplastic process (see below). Clinically, nodular fasciitis presents as a subcutaneous "growth" over a period of 3–6 weeks that eventually regresses. The lesion usually reaches a size of 2–3 cm. Larger lesions are unusual. Local recurrence has been described after simple surgical excision but it is rare.

In some instances nodular angiokeratomas can produce necrotic tissue and valleys that can harbor fungal, bacterial and viral infections. Infections can include staphylococcus. If the lesion becomes painful, begins draining fluids or pus, or begins to smell, consult a physician. In these instance a doctor may recommend excision and grafting.

It is a vascular malformation wherein blood vessels proliferate along with accompanying mature fat and fibrous tissue, lymphatics and sometimes nerves. They may involve skin, subcutaneous tissue, skeletal muscle and occasionally bone.

Prognosis depends on the size and location of the tumour, untreated angiomatosis may lead to blindness and/ or permanent brain damage. Death may occur, with complications in the kidney or brain.

Angiolipoleiomyoma is an acquired, solitary, asymptomatic acral nodule, characterized histologically by well-circumscribed subcutaneous tumors composed of smooth muscle cells, blood vessels, connective tissue, and fat.

Nodular fasciitis, also known as nodular pseudosarcomatous fasciitis, pseudosarcomatous fasciitis, and subcutaneous pseudosarcomatous fibromatosis, is a benign soft tissue lesion most commonly found in the superficial fascia. The lesion commonly occurs in the first three decades of life. Upper extremities and trunk are the most common affected anatomical sites. Previous history of trauma may be present. Clinically and histologically, nodular fasciitis may be mistaken for a sarcoma.

A tufted angioma (also known as an "Acquired tufted angioma," "Angioblastoma," "Angioblastoma of Nakagawa," "Hypertrophic hemangioma," "Progressive capillary hemangioma," and "Tufted hemangioma") usually develops in infancy or early childhood on the neck and upper trunk, and is an ill-defined, dull red macule with a mottled appearance, varying from 2 to 5 cm in diameter.

Cherry angiomas, also known as Campbell De Morgan spots or senile angiomas, are cherry red papules on the skin. They are a harmless (benign) tumor, containing an abnormal proliferation of blood vessels, and have no relationship to cancer. They are the most common kind of angioma, and increase with age, occurring in nearly all adults over 30 years.

Campbell de Morgan is the nineteenth-century British surgeon who first described them.

Spider angiomas are found only in the distribution of the superior vena cava, and are thus commonly found on the face, neck, upper part of the trunk, and arms. They may also be present on the backs of the hands and fingers in young children.

Patients present with a slow-growing, painless, solitary mass, usually of the subcutaneous tissues. It is much less frequently noted in the intramuscular tissue. It is not uncommon for symptoms to be present for years.

Benign neoplasm with "BROWN FAT" is noted.

A spider angioma (also known as a nevus araneus, spider nevus, vascular spider, and spider telangiectasia) is a type of telangiectasis (swollen blood vessels) found slightly beneath the skin surface, often containing a central red spot and reddish extensions which radiate outwards like a spider's web. They are common and may be benign, presenting in around 10–15% of healthy adults and young children. However, having more than three spider angiomas is likely to be abnormal and may be a sign of liver disease. It also suggests the probability of esophageal varices.

Giant-cell fibroblastoma is a rare type of soft-tissue tumor marked by painless nodules in the dermis (the inner layer of the two main layers of tissue that make up the skin) and subcutaneous (beneath the skin) tissue. These tumors may come back after surgery, but they do not spread to other parts of the body. They occur mostly in boys and are related to dermatofibrosarcoma protuberans.

Fibroma of tendon sheath is a benign tumor that presents as a small subcutaneous nodule that slowly increases in size. The tumors often have a multinodular growth pattern, with individual nodules being composed of bland, slender, spindle-shaped cells (myofibroblasts) in a dense, fibrous matrix.” A common microscopic finding is the presence of elongated, slit-like blood vessels. The lesions nearly always arise in the distal portions of the extremities. They often occur on the fingers, hands, toes, or feet. Although they are benign, they may recur in up to 40% of cases.

Although they may be regarded as a tumor of the skin, the lesions arise from tendons and aponeuroses in superficial sites, and are therefore properly classified as in the category "soft tissue tumor."

The biological nature of Fibroma of tendon sheath is not known, but the category appears to comprise a number of different pathologic processes. It is considered that about one-third of the lesions in this category may be acral variants of the entity, nodular fasciitis.

Weber–Christian disease, also known as relapsing febrile nodular nonsuppurative panniculitis, is a cutaneous condition characterized by recurrent subcutaneous nodules that heal with depression of the overlying skin.

It is type of panniculitis.

It is a rare disease seen in females 30–60 years of age. It is a recurring inflammation of fatty layers of tissue present beneath the skin. Clinical course is characterised by exacerbations and remissions. Lesions are bilaterally symmetrical and are usually seen in the lower legs.

LCAs most often are not clinically detectable. On occasion, their first presentation may be with splenic rupture.

Most patients show no symptoms and the tumours are found incidentally.

Involutional lipoatrophy is a cutaneous condition, and is an idiopathic lipoatrophy characterized clinically by non-inflammatory focal loss of fat.

Idiopathic localized involutional lipoatrophy (ILIL) is a rare and nosologically imprecise condition characterized by a focal loss of subcutaneous tissue on one or several sites, occurring without any significant triggering factor or auto-immune background, and regressing spontaneously within a few months.

There are three distinct types of lymphangioma, each with their own symptoms. They are distinguished by the depth and the size of abnormal lymph vessels, but all involve a malformation of the lymphic system. Lymphangioma circumscriptum can be found on the skin's surface, and the other two types of lymphangiomas occur deeper under the skin.

- Lymphangioma circumscriptum, a microcystic lymphatic malformation, resembles clusters of small blisters ranging in color from pink to dark red. They are benign and do not require medical treatment, although some patients may choose to have them surgically removed for cosmetic reasons.

- Cavernous lymphangiomas are generally present at birth, but may appear later in the child's life. These bulging masses occur deep under the skin, typically on the neck, tongue and lips, and vary widely in size, ranging from as small as a centimeter in diameter to several centimeters wide. In some cases, they may affect an entire extremity such as a hand or foot. Although they are usually painless, the patient may feel mild pain when pressure is exerted on the area. They come in the colors white, pink, red, blue, purple, and black; and the pain lessens the lighter the color of the bump.

- Cystic hygroma shares many commonalities with cavernous lymphangiomas, and some doctors consider them to be too similar to merit separate categories. However, cystic lymphangiomas usually have a softer consistency than cavernous lymphangiomas, and this term is typically the one that is applied to lymphangiomas that develop in fetuses. They usually appear on the neck (75%), arm pit or groin areas. They often look like swollen bulges underneath the skin.

This lesion has been called a fetal lipoma, lipoma of embryonic fat or a lipoma of immature fat.

Sclerema neonatorum is a rare and severe skin condition that is characterized by diffuse hardening of the subcutaneous tissue with minimal inflammation. It usually affects premature, ill newborns. Prognosis is poor.

Minimal inflammation helps distinguish sclerema neonaturum from subcutaneous fat necrosis of the newborn.

Littoral cell angioma, abbreviated LCA, and formally known as littoral cell angioma of the spleen, is a benign tumour of the spleen that arises from the cells that line the red pulp.

Angioma serpiginosum is characterized by minute, copper-colored to bright red angiomatous puncta that have a tendency to become papular.

"Configuration" refers to how lesions are locally grouped ("organized"), which contrasts with how they are distributed (see next section).

- Agminate: in clusters

- Annular or circinate: ring-shaped

- Arciform or arcuate: arc-shaped

- Digitate: with finger-like projections

- Discoid or nummular: round or disc-shaped

- Figurate: with a particular shape

- Guttate: resembling drops

- Gyrate: coiled or spiral-shaped

- Herpetiform: resembling herpes

- Linear

- Mammillated: with rounded, breast-like projections

- Reticular or reticulated: resembling a net

- Serpiginous: with a wavy border

- Stellate: star-shaped

- Targetoid: resembling a bullseye

- Verrucous: wart-like

Many conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square meters, and is made of three distinct layers: the epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin. Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. In the embryo, the epidermis, hair, and glands form from the ectoderm, which is chemically influenced by the underlying mesoderm that forms the dermis and subcutaneous tissues.

The epidermis is the most superficial layer of skin, a squamous epithelium with several strata: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. Nourishment is provided to these layers by diffusion from the dermis, since the epidermis is without direct blood supply. The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95 percent of the epidermis. This stratified squamous epithelium is maintained by cell division within the stratum basale, in which differentiating cells slowly displace outwards through the stratum spinosum to the stratum corneum, where cells are continually shed from the surface. In normal skin, the rate of production equals the rate of loss; about two weeks are needed for a cell to migrate from the basal cell layer to the top of the granular cell layer, and an additional two weeks to cross the stratum corneum.

The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing.

The subcutaneous tissue is a layer of fat between the dermis and underlying fascia. This tissue may be further divided into two components, the actual fatty layer, or panniculus adiposus, and a deeper vestigial layer of muscle, the panniculus carnosus. The main cellular component of this tissue is the adipocyte, or fat cell. The structure of this tissue is composed of septal (i.e. linear strands) and lobular compartments, which differ in microscopic appearance. Functionally, the subcutaneous fat insulates the body, absorbs trauma, and serves as a reserve energy source.

Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying etiologies and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology (chronic blistering conditions), etiology (skin conditions resulting from physical factors), and so on. Clinically, the diagnosis of any particular skin condition is made by gathering pertinent information regarding the presenting skin lesion(s), including the location (such as arms, head, legs), symptoms (pruritus, pain), duration (acute or chronic), arrangement (solitary, generalized, annular, linear), morphology (macules, papules, vesicles), and color (red, blue, brown, black, white, yellow). Diagnosis of many conditions often also requires a skin biopsy which yields histologic information that can be correlated with the clinical presentation and any laboratory data.