Melanoma is a type of skin cancer that begins in pigment-producing cells called melanocytes. This cancer typically occurs in areas that are only occasionally sun-exposed; tumors are most commonly found on the back in men and on the legs in women. Melanoma usually occurs on the skin (cutaneous melanoma), but in about 5 percent of cases it develops in melanocytes in other tissues, including the eyes (uveal melanoma) or mucous membranes that line the body's cavities, such as the moist lining of the mouth (mucosal melanoma). Melanoma can develop at any age, but it most frequently occurs in people in their fifties to seventies and is becoming more common in teenagers and young adults.\n\nA large number of moles or other pigmented skin growths on the body, generally more than 25, is associated with an increased risk of developing melanoma. Melanoma is also a common feature of genetic syndromes affecting the skin such as xeroderma pigmentosum. Additionally, individuals who have previously had melanoma are nearly nine times more likely than the general population to develop melanoma again. It is estimated that about 90 percent of individuals with melanoma survive at least 5 years after being diagnosed.\n\nMelanoma may develop from an existing mole or other normal skin growth that becomes cancerous (malignant); however, many melanomas are new growths. Melanomas often have ragged edges and an irregular shape. They can range from a few millimeters to several centimeters across. They can also be a variety of colors: brown, black, red, pink, blue, or white.\n\nMost melanomas affect only the outermost layer of skin (the epidermis). If a melanoma becomes thicker and involves multiple layers of skin, it can spread to other parts of the body (metastasize).

Squamous cell carcinoma of the skin is a malignant tumor of squamous epithelium.

The presence of a basal cell carcinoma of the skin.

Reduced volume of the testicle (the male gonad).

An abnormality of the dermatoglyphs, i.e., an abnormality of the patterns of ridges of the skin of palm of hand.

An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.

A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms).

Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.

Difficulty in swallowing.

A condition in which the stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter.

A reduction in erythrocytes volume or hemoglobin concentration.

Head circumference below 2 standard deviations below the mean for age and gender.

Decreased levels of immunoglobulin A (IgA).

An abnormally decreased level of immunoglobulin M (IgM) in blood.

Increased susceptibility to infections.

An abnormally decreased level of immunoglobulin G (IgG) in blood.

A thickened white patch on the oral mucosa that cannot be rubbed off.

Any abnormality of the teeth.

A noncongenital process of hair loss, which may progress to partial or complete baldness.

Onychodystrophy (nail dystrophy) refers to nail changes apart from changes of the color (nail dyschromia) and involves partial or complete disruption of the various keratinous layers of the nail plate.

An abnormality of the pigmentation of the skin.

Decreased density/number of eyelashes.

Abnormally increased lacrimation, that is, excessive tearing (watering eye).

An abnormal reduction in telomere length. Telomeres are non-coding, repetitive sequences of DNA at the ends of the chromosomes of eukaryotic cells which become shorter as cells divide, and when telomere attrition reaches its limit, cell proliferation arrest, senescence, and apoptosis can occur.