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The decision to observe or treat a nevus may depend on a number of factors, including cosmetic concerns, irritative symptoms (e.g., pruritus), ulceration, infection, and concern for potential malignancy.
Large and especially giant congenital nevi are at higher risk for malignancy degeneration into melanoma. Because of the premalignant potential, it is an acceptable clinical practice to remove congenital nevi electively in all patients and relieve the nevocytic overload.
Surgical excision is the standard of care. Some individuals advocate the use of hair removal laser for the treatment of congenital nevi. While this is likely safe and effective for small congenital nevus, laser removal for larger lesions might pose a liability for the laser surgeon if malignancy developed from a deep (dermal) component of the nevus that is not reached by the laser. Repigmentation after laser treatment of congenital nevi or superficial curettage supports this concern.
Many are surgically removed for aesthetics and relief of psychosocial burden, but larger ones are also excised for prevention of cancer, although the benefit is impossible to assess for any individual patient. Proliferative nodules are usually biopsied and are regularly but not systematically found to be benign. Estimates of transformation into melanoma vary from 2-42% in the literature, but are most commonly considered to be at the low end of that spectrum due to early observer bias.
The management of a nevus depends on the specific diagnosis, however, the options for treatment generally include the following modalities:
Experts, such as the American Academy of Dermatology, say that vast majority of moles are benign. Nonetheless, the U.S. National Cancer Institute estimated that 62,480 new cases of melanoma and 8,420 related deaths would appear in the United States in the year 2008.
Data on the chances of transformation from melanocytic nevi to melanoma is controversial, but it appears that about 10% of malignant melanomas have a precursor lesion, of which about 10% are melanocytic nevi. Therefore, it appears that malignant melanoma quite seldomly (1% of cases) has a melanocytic nevi as a precursor.
No treatment of seborrheic keratoses is necessary, except for aesthetic reasons. Since a slightly increased risk of localized infection caused by picking at the lesion has been described, if a lesion becomes itchy or irritated by clothing or jewelry, a surgical excision is generally recommended.
Small lesions can be treated with light electrocautery. Larger lesions can be treated with electrodesiccation and curettage, shave excision, or cryosurgery. When correctly performed, removal of seborrheic keratoses will not cause much visible scarring except in persons with dark skin tones.
First, a diagnosis must be made. If the lesion is a seborrheic keratosis, then shave excision, electrodesiccation or cryosurgery may be performed, usually leaving very little if any scarring. If the lesion is suspected to be a skin cancer, a skin biopsy must be done first, before considering removal. This is unless an excisional biopsy is warranted. If the lesion is a melanocytic nevus, one has to decide if it is medically indicated or not
If a melanocytic nevus is suspected of being a melanoma, it needs to be sampled or removed and sent for microscopic evaluation by a pathologist by a method called skin biopsy. One can do a complete excisional skin biopsy or a punch skin biopsy, depending on the size and location of the original nevus. Other reasons for removal may be cosmetic, or because a raised mole interferes with daily life (e.g. shaving). Removal can be by excisional biopsy or by shaving. A shaved site leaves a red mark on the site which returns to the patient’s usual skin color in about two weeks. However, there might still be a risk of spread of the melanoma, so the methods of Melanoma diagnosis, including excisional biopsy, are still recommended even in these instances. Additionally, moles can be removed by laser, surgery or electrocautery.
In properly trained hands, some medical lasers are used to remove flat moles level with the surface of the skin, as well as some raised moles. While laser treatment is commonly offered and may require several appointments, other dermatologists think lasers are not the best method for removing moles because the laser only cauterizes or, in certain cases, removes very superficial levels of skin. Moles tend to go deeper into the skin than non-invasive lasers can penetrate. After a laser treatment a scab is formed, which falls off about seven days later, in contrast to surgery, where the wound has to be sutured. A second concern about the laser treatment is that if the lesion is a melanoma, and was misdiagnosed as a benign mole, the procedure might delay diagnosis. If the mole is incompletely removed by the laser, and the pigmented lesion regrows, it might form a recurrent nevus.
Electrocautery is available as an alternative to laser cautery. Electrocautery is a procedure that uses a light electrical current to burn moles, skin tags, and warts off the skin. Electric currents are set to a level such that they only reach the outermost layers of the skin, thus reducing the problem of scarring. Approximately 1-3 treatments may be needed to completely remove a mole. Typically, a local anesthetic is applied to the treated skin area before beginning the mole removal procedure.
For surgery, many dermatologic and plastic surgeons first use a freezing solution, usually liquid nitrogen, on a raised mole and then shave it away with a scalpel. If the surgeon opts for the shaving method, he or she usually also cauterizes the stump. Because a circle is difficult to close with stitches, the incision is usually elliptical or eye-shaped. However, freezing should not be done to a nevus suspected to be a melanoma, as the ice crystals can cause pathological changes called "freezing artifacts" which might interfere with the diagnosis of the melanoma.
Also known as "scoop", "scallop", or "shave" excisional biopsy, or "shave excision". A trend has occurred in dermatology over the last 10 years with the advocacy of a deep shave excision of a pigmented lesion An author published the result of this method and advocated it as better than standard excision and less time consuming. The added economic benefit is that many surgeons bill the procedure as an excision, rather than a shave biopsy. This save the added time for hemostasis, instruments, and suture cost. The great disadvantage, seen years later is the numerous scallop scars, and a very difficult to deal with lesions called a "recurrent melanocytic nevus". What has happened is that many "shave" excisions does not adequately penetrate the dermis or subcutanous fat enough to include the entire melanocytic lesion. Residual melanocytes regrow into the scar. The combination of scarring, inflammation, blood vessels, and atypical pigmented streaks seen in these recurrent nevus gives the perfect dermatoscopic picture of a melanoma. When a second physicians re-examine the patient, he or she has no choice but to recommend the reexcision of the scar. If one does not have access to the original pathology report, it is impossible to tell a recurring nevus from a severely dysplastic nevus or a melanoma. As the procedure is widely practiced, it is not unusual to see a patient with dozens of scallop scars, with as many as 20% of the scars showing residual pigmentation. The second issue with the shave excision is fat herniation, iatrogenic anetoderma, and hypertrophic scarring. As the deep shave excision either completely remove the full thickness of the dermis or greatly diminishing the dermal thickness, subcutanous fat can herniate outward or pucker the skin out in an unattractive way. In areas prone to friction, this can result in pain, itching, or hypertrophic scarring.
Seborrheic keratosis is the most common benign skin tumor. Incidence increases with age. There is less prevalence in people with darker skin. In large-cohort studies, 100% of the patients over age 50 had at least one seborrheic keratosis. Onset is usually in middle age, although they are common in younger patients too—found in 12% of 15-year-olds to 25-year-olds—making the term "senile keratosis" a misnomer.
Spitz nevi are uncommon. Their annual incidence was estimated in a coastal population of sub-tropical Queensland to be 1.4 cases per 100,000 people. For comparison, the annual incidence of melanoma in the same population, which is high by world standards is 25.4 cases per 100,000 people.
Although they are most commonly found on people in their first two decades of life, the age range for people with Spitz nevi is from 6 months to 71 years, with a mean age of 22 years and a median age of 19 years.
Blue nevus (also known as "blue neuronevus", "dermal melanocytoma", and "nevus bleu") is a type of melanocytic nevus. The blue colour is caused by the pigment being deeper in the skin than in ordinary nevi. In principle they are harmless but they can sometimes be mimicked by malignant lesions, i.e. some melanomas can look like a blue nevus.
The best treatment of lentigo maligna is not clear as it has not been well studied.
Standard excision is still being done by most surgeons. Unfortunately, the recurrence rate is high (up to 50%). This is due to the ill defined visible surgical margin, and the facial location of the lesions (often forcing the surgeon to use a narrow surgical margin). The use of dermatoscopy can significantly improve the surgeon's ability to identify the surgical margin. The narrow surgical margin used (smaller than the standard of care of 5 mm), combined with the limitation of the standard bread loafing technique of fixed tissue histology - result in a high "false negative" error rate, and frequent recurrences. Margin controlled (peripheral margins) is necessary to eliminate the false negative errors. If breadloafing is utilized, distances from sections should approach 0.1 mm to assure that the method approaches complete margin control.
Where the lesion is on the face and either large or 5mm margins are possible, a skin flap or skin graft may be indicated/required. Grafts have their own risks of failure and poor cosmetic outcomes. Flaps can require extensive incision resulting in long scars and may be better done by plastic surgeons (and possibly better again by those with extensive LM or "suspicious of early malignant melanoma" experience.
Mohs surgery has been done with cure rate reported to be 77%. The "double scalpel" peripheral margin controlled excision method approximates the Mohs method in margin control, but requires a pathologist intimately familiar with the complexity of managing the vertical margin on the thin peripheral sections and staining methods.
Some melanocytic nevi, and melanoma-in-situ (lentigo maligna) have resolved with an experimental treatment, imiquimod (Aldara) topical cream, an immune enhancing agent. In view of the very poor cure rate with standard excision, some surgeons combine the two methods: surgical excision of the lesion, then three months treatment of the area with imiquimod cream.
Studies seem to conflict about the level of certainty associated with using imiquimod.
Another treatment to be considered where standard margins cannot be achieved or cosmetics are a major consideration is ultra-soft x-ray/grenz-ray radiation.
In the very elderly or those with otherwise limited life expectancy, the impact of major day surgery for excision with 5mm margins and large skin flap could be worse than doing nothing or the possibility of failed treatments with imiquimod or Grenz ray.
Nevus sebaceus or sebaceous nevus (the first term is its Latin name, the second term is its name in English; also known as an "organoid nevus" and "nevus sebaceus of Jadassohn") is a congenital, hairless plaque that typically occurs on the face or scalp. Such nevi are present at birth, or early childhood, affecting males and females of all races equally. The condition is named for an overgrowth of sebaceous glands in the area of the nevus.
Skin growths such as benign tumors and basal cell carcinoma can arise in sebaceous nevi, usually in adulthood. Rarely, sebaceous nevi can give rise to sebaceous carcinoma. However, the rate of such malignancies is now known to be less than had been estimated. For this reason, excision is no longer automatically recommended.
Pseudomelanoma (also known as a "recurrent melanocytic nevus", and "recurrent nevus") is a cutaneous condition in which melantic skin lesions clinically resemble a superficial spreading melanoma at the site of a recent shave removal of a melanocytic nevus.
Superficial spreading melanoma (also known as "superficially spreading melanoma") (SSM) is usually characterized as the most common form of cutaneous melanoma in Caucasians. The average age at diagnosis is in the fifth decade, and it tends to occur on sun-exposed skin, especially on the backs of males and lower limbs of females.
Melanoma with features of a Spitz nevus (also known as a "Spitzoid melanoma") is a cutaneous condition characterized histologically with tissue similar to a spitz nevus and with overall symmetry and a dermal nodule of epithelioid melanocytes that do not mature with progressively deeper dermal extension.
Verruciform xanthoma is an uncommon benign lesion that has a verruciform (wart-like) appearance, but it may appear polypoid, papillomatous, or sessile. The verruciform was first described by Shafer in 1971 on the oral mucosa. Usually found on the oral mucosa of middle-aged persons, verruciform xanthomas have also been reported on the scrotum and penis of middle-aged to elderly Japanese males. While the most common site is the oral mucosa, lesions that occur elsewhere usually arise on the perineum or on the skin with some predisposing factor, such as lymphedema or an epidermal nevus.
Nevoid melanoma is a cutaneous condition that may resemble a Spitz nevus or an acquired or congenital melanocytic nevus.
Verruciform xanthoma is uncommon, with a female:male ratio of 1:1.1
Epithelioma cuniculatum (also known as Carcinoma cuniculatum, and Ackerman tumor) is a skin lesion, a type of verrucous carcinoma that may occur on the sole of the foot.
Linear verrucous epidermal nevus (also known as a "Linear epidermal nevus," and "Verrucous epidermal nevus") is a skin lesion characterized by a verrucous skin-colored, dirty-gray or brown papule. Generally, multiple papules present simultaneously, and coalesce to form a serpiginous plaque. When this nevus covers a diffuse or extensive portion of the body's surface area, it may be referred to as a systematized epidermal nevus, when it involved only one-half of the body it is called a nevus unius lateris.
As halo nevi are only of cosmetic significance, no treatment is required, and patients will be asymptomatic. Although halo nevi are harmless, it is important to monitor the lesion on regular basis. Watch out for any changes in appearance of existing or new halo nevi. If there is any change in appearance or is associated with pain, itch, and infection, a doctor should be consulted immediately to exclude the possibility of melanoma.
Usually observed at birth or shortly thereafter in 94% of patients, in other reports, patients did not develop skin lesions until 3 months or even 2 years after birth. Females are typically affected more often than males (64%).
A Spitz nevus (also known as an epithelioid and spindle-cell nevus, benign juvenile melanoma, and "Spitz's juvenile melanoma") is a benign melanocytic nevus, a type of skin lesion, affecting the epidermis and dermis.
The name "juvenile melanoma" is generally no longer used as it is misleading: it is not a melanoma, it is a benign lesion; and it can also occur in adults, not only in children.
Outpatient treatments such as interventional radiology, lasers, and physical therapy are employed to reduce the severity of the vascular lesions. However, in some cases lasers have caused a reaction in the tissue causing it to expand and become exposed to infection. Excision and grafting may be necessary to remove the lesion. Recovery time on such an operation ranges from 3 to 12 weeks depending on location of the graft, healing time and the possibility of complications.