(Nonmelanoma Skin Cancer)
Skin cancer is the most common form of human cancer. It is
estimated that over 1 million new cases occur annually. The annual rates of all
forms of skin cancer are increasing each year, representing a growing public
concern. It has also been estimated that nearly half of all Americans who live
to age 65 will develop skin cancer at least once.
The most common warning sign of skin cancer is a change in the
appearance of the skin, such as a new growth or a sore that will not heal.
The term "skin cancer" refers to three different
conditions. From the least to the most dangerous, they are:
basal cell carcinoma
(or basal cell carcinoma epithelioma)
squamous cell
carcinoma (the first stage of which is called actinic keratosis)
melanoma
The two most common forms of skin cancer are basal cell
carcinoma and squamous cell carcinoma. Together, these two are also referred to
as nonmelanoma skin cancer. Melanoma is generally the most serious form of skin
cancer because it tends to spread (metastasize) throughout the body quickly.
Skin cancer is also known as skin neoplasia.
This article will discuss the two kinds of nonmelanoma skin
cancer.
Basal cell carcinoma
What is basal cell carcinoma?
Basal cell carcinoma is the most common form of skin cancer and
accounts for more than 90% of all skin cancer in the U.S. These cancers almost
never spread (metastasize) to other parts of the body. They can, however, cause
damage by growing and invading surrounding tissue.
What are risk factors for developing basal cell carcinoma?
Light-colored skin, sun exposure, and age are all important
factors in the development of basal cell carcinomas. People who have fair skin
and are older have higher rates of basal cell carcinoma. About 20% of these
skin cancers, however, occur in areas that are not sun-exposed, such as the
chest, back, arms, legs, and scalp. The face, however, remains the most common
location for basal cell lesions. Weakening of the immune system, whether by
disease or medication, can also promote the risk of developing basal cell
carcinoma. Other risk factors include
exposure to sun. There is evidence that, in contrast to squamous
cell carcinoma, basal cell carcinoma is promoted not by accumulated sun
exposure but by intermittent sun exposure like that received during vacations,
especially early in life. According to the U.S. National Institutes of Health,
ultraviolet (UV) radiation from the sun is the main cause of skin cancer. The
risk of developing skin cancer is also affected by where a person lives. People
who live in areas that receive high levels of UV radiation from the sun are
more likely to develop skin cancer. In the United States, for example, skin
cancer is more common in Texas than it is in Minnesota, where the sun is not as
strong. Worldwide, the highest rates of skin cancer are found in South Africa and
Australia, which are areas that receive high amounts of UV radiation.
age. Most skin cancers
appear after age 50, but the sun's damaging effects begin at an early age.
Therefore, protection should start in childhood in order to prevent skin cancer
later in life.
exposure to
ultraviolet radiation in tanning booths. Tanning booths are very popular,
especially among adolescents, and they even let people who live in cold
climates radiate their skin year-round.
therapeutic radiation,
such as that given for treating other forms of cancer.
What does basal cell carcinoma look like?
A basal cell carcinoma usually begins as a small, dome-shaped
bump and is often covered by small, superficial blood vessels called
telangiectases. The texture of such a spot is often shiny and translucent,
sometimes referred to as "pearly." It is often hard to tell a basal
cell carcinoma from a benign growth like a flesh-colored mole without
performing a biopsy. Some basal cell carcinomas contain melanin pigment, making
them look dark rather than shiny.
Superficial basal cell carcinomas often appear on the chest or
back and look more like patches of raw, dry skin. They grow slowly over the
course of months or years.
Basal cell carcinomas grow slowly, taking months or even years
to become sizable. Although spread to other parts of the body (metastasis) is very
rare, a basal cell carcinoma can damage and disfigure the eye, ear, or nose if
it grows nearby.
How is basal cell carcinoma diagnosed?
To make a proper diagnosis, doctors usually remove all or part
of the growth by performing a biopsy. This usually involves taking a sample by
injecting a local anesthesia and scraping a small piece of skin. This method is
referred to as a shave biopsy. The skin that is removed is then examined under
a microscope to check for cancer cells.
How is basal cell carcinoma treated?
There are many ways to successfully treat a basal cell carcinoma
with a good chance of success of 90% or more. The doctor's main goal is to
remove or destroy the cancer completely with as small a scar as possible. To
plan the best treatment for each patient, the doctor considers the location and
size of the cancer, the risk of scarring, and the person's age, general health,
and medical history.
Methods used to treat basal cell carcinomas include:
Curettage and
desiccation: Dermatologists often prefer this method, which consists of
scooping out the basal cell carcinoma by using a spoon like instrument called a
curette. Desiccation is the additional application of an electric current to
control bleeding and kill the remaining cancer cells. The skin heals without
stitching. This technique is best suited for small cancers in non-crucial areas
such as the trunk and extremities.
Surgical excision: The
tumor is cut out and stitched up.
Radiation therapy:
Doctors often use radiation treatments for skin cancer occurring in areas that
are difficult to treat with surgery. Obtaining a good cosmetic result generally
involves many treatment sessions, perhaps 25 to 30.
Cryosurgery: Some
doctors trained in this technique achieve good results by freezing basal cell
carcinomas. Typically, liquid nitrogen is applied to the growth to freeze and
kill the abnormal cells.
Mohs micrographic
surgery: Named for its pioneer, Dr. Frederic Mohs, this technique of removing
skin cancer is better termed "microscopically controlled excision."
The surgeon meticulously removes a small piece of the tumor and examines it
under the microscope during surgery. This sequence of cutting and microscopic
examination is repeated in a painstaking fashion so that the basal cell carcinoma
can be mapped and taken out without having to estimate or guess the width and
depth of the lesion. This method removes as little of the healthy normal tissue
as possible. Cure rate is very high, exceeding 98%. Mohs micrographic surgery
is preferred for large basal cell carcinomas, those that recur after previous
treatment, or lesions affecting parts of the body where experience shows that
recurrence is common after treatment by other methods. Such body parts include
the scalp, forehead, ears, and the corners of the nose. In cases where large
amounts of tissue need to be removed, the Mohs surgeon sometimes works with a
plastic (reconstructive) surgeon to achieve the best possible postsurgical
appearance.
Medical therapy using
creams that attack cancer cells (5-Fluorouracil--5-FU, Efudex, Fluoroplex) or
stimulate the immune system (imiquimod [Aldara]). These are applied several
times a week for several weeks. They produce brisk inflammation and irritation.
The advantages of this method is that it avoids surgery, lets the patient
perform treatment at home, and may give a better cosmetic result. Disadvantages
include discomfort, which may be severe, and a lower cure rate, which makes
medical treatment unsuitable for treating most skin cancers on the face.
How is basal cell carcinoma prevented?
Avoiding sun exposure in susceptible individuals is the best way
to lower the risk for all types of skin cancer. Regular surveillance of
susceptible individuals, both by self-examination and regular physical
examination, is also a good idea for people at higher risk. People who have
already had any form of skin cancer should have regular medical checkups.
Common sense preventive techniques include
limiting recreational
sun exposure;
avoiding unprotected
exposure to the sun during peak radiation times (the hours surrounding noon);
wearing broad-brimmed
hats and tightly-woven protective clothing while outdoors in the sun;
regularly using a
waterproof or water resistant sunscreen with UVA protection and SPF 30 or
higher;
undergoing regular
checkups and bringing any suspicious-looking or changing lesions to the
attention of the doctor; and
avoiding the use of
tanning beds and using a sunscreen with an SPF of 30 and protection against UVA
(long waves of ultraviolet light.). Many people go out of their way to get an
artificial tan before they leave for a sunny vacation, because they want to get
a "base coat" to prevent sun damage. Even those who are capable of
getting a tan, however, only get protection to the level of SPF 6, whereas the
desired level is an SPF of 30. Those who only freckle get little or no
protection at all from attempting to tan; they just increase sun damage.
Sunscreen must be applied liberally and reapplied every two to three hours,
especially after swimming or physical activity that promotes perspiration,
which can weaken even sunscreens labeled as "waterproof."
Veerapagupathy,
Chothavilai Beach,
Thengamputhoor,
Kanyakumari.
Call: 04652-221337, 9500946903.
email:aveholidayhome@gmail.com
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