Blue Nevi – Causes and Treatment
Blue nevi are blue-black moles also known as blue moles. They are commonly found on individuals that are of Asian descent. They are generally benign in nature even in the case that they are present for years. They are created by the pigment producing cells of the body collecting in one area that cause the formation called melanocytes. While they might be benign in most cases, new spots should be checked for cancer and melanoma.
There are two different types of blue nevus – the common blue and cellular blue. The common blue nevus is flat or slightly elevated and is presented in the form of a plaque or papule. It can vary in color between bluish-black and gray-blue. These spots are usually located on the upper surfaces of the hands and feet, the pelvic region, and on the head.
The cellular blue nevus at the beginning was thought to be a type of melanoma but is considered to be blue nevus even though this is still in debate. This is an uncommon type and they are usually large, between one and three centimeters in diameter.
Even though blue nevi are rare in documented cases of heredity, there are some suggestions that there may be a genetic predisposition towards this condition. They are often found in those of Asian descent that are in the United States and 60% of such individuals are found with them. This is much more than the 1%-2% of the white adult population and rarely even found amongst the black population. They also are rarely even found during birth, in infants or in children during their toddler stages. In fact, so rare that it is less than one child out of a thousand.
The blue color comes from the melanin that is in the epidermis in combination with the Tyndal effect. This Tyndal effect is created by the melanin taking in the certain long wavelengths of light with the shorter wavelengths which are then scattered. This in turn gives the blue color in the collagen bundles.
In most cases, these blue nevi remain benign even in the cases where the individual is experiencing symptoms with them. There have been rare cases where the spots have been identified as malignant melanoma. These cases are normally linked to the cellular blue nevi and not the common type. Women have been diagnosed with this condition more often than men and while the condition can appear at any age, the majority of the cases have been identified in patients that were in the twenties or older.