Moles are very common. In fact, in a New Zealand study of 872 adults, on average people were shown to have 15 moles of 2mm or greater in diameter and 39 total moles on their body of various sizes. (Source). That is a lot of moles. In fact, it is very rare for a person to have no moles at all, though some people are actually mole-less.
Moles can be a cause for alarm to people and their dermatologists, but most are completely harmless. And some moles in some places can be seen as beauty marks – but generally speaking, people seek to have their skin flawless and clear. And for them, as well as those who are worried about their moles, there are solutions. Laser treatment is one of those. As such, we at TSLMS see a lot of moles being removed.
What Are Moles
Moles, sometimes called skin moles, come in 3 types. As noted by UnityPoint Health:
Moles occur when melanocytes, which gives skin its natural color, grow in a cluster instead of being spread throughout the skin. The most common types of skin moles include:
- Congenital mole. Moles you’re born with.
- Common mole (also called acquired mole). Harmless moles that appear on the skin after birth. Most people have around 10-40 of these on their bodies. Having 50 or more increases the risk of melanoma.
- Atypical mole (also called dysplastic nevus). Moles that oftentimes have an odd shape, are larger than a pencil eraser and show more than one color. An atypical mole may look like melanoma but isn’t.
It’s important to know what your moles look like…Moles can show up in some unusual places, like the scalp, palms, under nails and between fingers and toes. Knowing where your moles are and their appearance allows you to spot changes more easily, should they occur.
Most moles show up on the skin during childhood and adolescence. These moles grow and sometimes change in size and color (lightness or darkness) as we age. Moles should appear symmetrical and round, with clearly-defined borders. They may be flat or raised, but should be smaller than a pencil eraser (6 millimeters). Moles should also be the same color throughout.
When A Mole Is More Than A Mole
The biggest concern that any of us have with moles, besides their aesthetics, is the potential for them to be melanomas. According to The National Cancer Institute, “Melanoma is a type of cancer that begins in melanocytes (cells that make the pigment melanin). Melanoma can also start in the eye, the intestines, or other areas of the body with pigmented tissues. Often the first sign of melanoma is a change in the shape, color, size, or feel of an existing mole. However, melanoma may also appear as a new mole. People should tell their doctor if they notice any changes on the skin. The only way to diagnose melanoma is to remove tissue and check it for cancer cells.”
Our members see a lot of people who are concerned that their moles have turned into melanoma. If they are not trained dermatologists or have solid oncology training, it can be a little bit confusing. This is why it is always best to have a suspicious mole removed and biopsied. Especially if it is bleeding, oozing, changed color or is otherwise like a melanoma.
For most of the last decade laser technology has allowed for the removal of moles. An article published by the National Institutes of Health in 2013 defines the process as it existed then (technology has advanced since then and is still advancing):
Like any other indication, the use of lasers in pigmented lesions begins at the helm of laser physics and depends on the absorption spectra of the target chromophore, which is the melanocyte (melanosome). In congenital nevi, there are other issues like variegation of pigment and depth. In moles (CAMN), freckles, and lentigines, the target chromophore lies either in the epidermis (freckles, lentigines) or in the dermis (CAMN), which influences the success of the pigment lasers employed for therapy. For melanin, there is a wide array of lasers that can be used ranging from the green lasers (PDL, QSw, Nd: YAG 532) to the far infrared lasers (CO2 10, 600 nm, Er: YAG2940 nm). The second important proviso is to minimize the heat damage that requires optimal setting of the pulse duration of the laser. Thus, a laser with a pulse duration less or equal to the TRT should be employed. This depends on the size of the target tissue that dictates thermal relaxation time (TRT), which is 0.25-1.00 μs for the melanosome and 0.1 ms (100 μs) for the melanocyte. Herein lies the logic of using nanosecond lasers (Q switched) to treat pigmented lesions like lentigines, freckles, and Nevus of Ota and the futility of this in treating “moles” with nanosecond lasers. Lack of reproducible results in CAN can be attributed to the fact that the target nevus cell occur in clusters and are of larger size than melanocytes and, thus, need a millisecond laser for effective ablation. This is the main reason why normal mode, non pulsed lasers, and far infrared lasers are used to treat CAM.[2,4,5] The third requirement is to achieve an adequate depth to target the chromophore for which the red (Ruby 694 nm, Alexandrite 755 nm) and near-infrared (QseNd: YAG 1064 nm) lasers (approximately 600–1100 nm) are ideal. These lasers combine selective absorption by melanin with an appropriate skin penetration. Based on these three principles, the devices useful for treating melanocytic lesions are of two basic classes:[2,5] far-infrared skin resurfacing lasers and pulsed lasers/IPLs. The pulsed lasers are further divided into long-pulse (millisecond) devices, which tend to target relatively large pigmented structures such as hair follicles and “nests” of nevus cells, and short-pulse (Q-switched nanosecond lasers) devices, which are capable of targeting individual pigmented cells. Histologically, though CAN have both isolated nevo-melanocyte cells and “nests” or clusters of cells[2,5] Thus, ideally, a mixture of lasers targeting both should be used, with the use of short (ns) pulses and long (ms) pulses.[2,5] This is the reason why melanocytic nevus are better treated with a combination of lasers. Recent studies used pulsed CO2 ostensibly to ensure fine ablation of the epidermis, followed by a Qs fd Nd: YAG, Qs Nd: YAG, or Qs ALex laser. The logic employed in the use of combination lasers[4,5] (normal mode and Q-switched ruby laser, CO2 and Qs AL, CO2 and Qsfd Nd: YAG laser, CO2 and Q-switched ruby laser) was to expose the otherwise unaffected, deep-seated nevomelanocytes to the pigment-specific laser. Nevus cells in the superficial dermis are additionally removed by the CO2 laser. Alternatively, for a smaller “mole” (<1.5 cm), a short-pulsed Er: YAG would be an ideal tool as apart from the pulse duration (300-1000 μs), the Er:YAG has a predictable depth (5 μm/J/cm2), minimal thermal damage (20–30 μm), and a high absorption coefficient of water (Er:YAG 12,800 cm−1; CO2800 cm−1) and is thus capable of a far finer and safer superficial ablation with minimal sequel. A comparison of various modalities at our centre shows that the combined or pulsed ablative method is better than using the Qsw lasers for CAMN.
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