As we now know, hyperpigmentation comes in many forms that are usually called age spots, sun spots, brown spots and melasma. But common to all is the presence of melanin in the body. Ephelides, Lentigo, and Pigmented naevi are all similar in nature. Dysplastic naevi, and Malignant melanoma have much in common. Melasma or (Chloasma), Phyto-photo dermatitis, and Ochronosis also share common characteristics.
Ephelides is another word for what we know as freckles. They are small, evenly pigmented macules which are more obvious after sun exposure. They are caused by an increase in the melanin in a normal number of melanocytes(producers of melanin). Ephelides often occur on the face, arms, legs and nose, and in fair skinned or red-haired people.
Lentigo is the Latin word for lentil. As such, lentigo resembles lentils in its appearance and form. The lesions of lentigo are called lentigines and they are more defined and darker than freckles. Also, they are slightly raised and distributed in no particular order. They are the result of an increase in the number of melanocytes found in the basal layer of the epidermis.
Pigmented naevi, otherwise known as moles, are tumours of melanocyte cells and usually appear in early adulthood and throughout life. They are usually small (less than 1cm in diameter) and can be skin coloured to light brown to blue black. There are three types of pigmented naevi: intradermal,
junctional, and compound.
It is important to note that intradermal naevi are usually never malignant. They occur in adults and are dome-shaped, papillomatous, or pedunculated. They may or may not have hairs and they can appear anywhere on the body especially the head and neck. Intradermal naevi are not, however, usually found on the palms, soles, or genetalia. They are shades of brown or even skintone in colour, and are found completely within the dermis of the skin.
Junctional naevi, on the other hand, are found mainly on the soles, palms, and genetalia. They can be flat or slightly raised. Actually, they can be found anywhere on the body and they are hairless. A small percentage of the naevi can go on to become Malignant melanomas. The junctional naevi are found where the dermis and the epidermis meet (ie.,dermo-epidermal junction).
Compound naevi have both intradermal and junctional components because they are located in both the intradermal part of the dermis and dermo-epidermal junction. They are raised and papillomatous even though they are like intradermal naevi. They have coarse dark hairs and a small percentage can become malignant(junctionalcompnent).
How can you tell if a naevus is malignant? Many are benign, but the small percentage that change in appearance and behaviour (eg., inflammation) are likely to become malignant. If there is any pain, itching, bleeding, enlargement, darkening, or ulceration it should be checked out by a pathologist.
Hairs on the naevi do not always lead to malignancy. Intradermal moles generally have hairs and compound moles may have hairs because of their intradermal component. It is the junctional component of compound moles that can lead to malignancy. Only through a biopsy under dermatologist supervision (ie., under a microscope) can you be 100% certain of malignancy.
Dysplastic naevi have an irregular colour and shape (greater than 7mm in diameter) with an indistinct border both on biopsy and to the naked eye. They are considered atypical. Dysplastic naevi have a variegated appearance and must be monitored carefully because of their high risk to become Malignant melonoma.
Fortunately, these days there are many solutions for all hyperpigmentation disorders such as age spots, sun spots, melasma. These at Nell Laser Clinic include: Laser; micro-needling; microdermabrasion; chemical peel; electro-cauterization and cosmetic acupuncture. These treatments, with the aid of proper skin care products, will resolve hyperpigmentation. Patience and persistency, however, are key.
For more information and a complementary consultation call us at 416-228-0011