Author: Meng Yao, Doctor of Medicine, Zhongshan Hospital, Fudan University
Reviewed by: Xu Min, Deputy Chief Physician of Zhu Xianyi Memorial Hospital of Tianjin Medical University
Gossip
(Data map)
Recently, singer Zhang Hengyuan, who was only 36 years old, died because he suffered from melanoma. At one time, # melanoma # hit the microblog hot search, which attracted the attention of many netizens. At the same time, this also made many netizens panic, because many people had black spots on their bodies. So, could their black spots also be a dangerous "time bomb"? More frightening is that there is a rumor that the nevus is the predecessor of melanoma, which will become malignant sooner or later. Is that really the case? Today, let's make a concrete analysis.
Screenshot of Weibo
What is a mole?
Will nevus definitely develop into melanoma?
Pigmented nevus, composed of nevus cells, is a benign skin tumor, also known as cell nevus and melanocytic nevus. It usually shows black or brown spots or protuberances, most of which are black. Most people begin to appear in childhood, and may have 10-40 in adulthood. According to the distribution of nevus cells, It can be divided into junction nevus, mixed nevus and intradermal nevus.
Pigmented nevus is generally harmless, and most pigmented nevus will not develop into melanoma! However, even if only a small part of them may become melanoma, we still cannot take it lightly!
What is melanoma?
The term skin cancer may be familiar to everyone, and the most harmful one is malignant melanoma. Melanoma is a highly malignant tumor derived from melanocytes, which is commonly found on the surface of the skin, especially the parts often exposed to sunlight, such as the face, arms, legs, etc. However, it may also appear in other parts, such as eyes, mouth, digestive tract, urinary tract, vagina, under nails, palms, heels, etc. There are four main subtypes of melanoma:
one
Malignant lentiginous nevus melanoma
It is common in the elderly and occurs in the skin area of chronic long-term sunlight exposure. The most common part is the face. It is manifested as irregular border, uneven gray or black.
Malignant lentiginous nevus melanoma
(Photo source: Dermatology and Venereology (3rd Edition))
two
Superficially diffused malignant melanoma
It is the most common subtype of cutaneous malignant melanoma, which is mainly found on the back of men and the legs of women. At first, it is usually flat patches or plaques, accompanied by scales, and gradually develops into flaky blue or blue black nodules. The color is mixed and changeable, which can be in different shades of brown, and occasionally mixed with black, blue, and red. Superficially diffused malignant melanoma grows rapidly, with infiltration, nodules, ulcers or bleeding within 2 years.
Superficially diffused malignant melanoma
(Photo source: Dermatology and Venereology (3rd Edition))
three
Acral Melanoma
This type is the most common tumor type among blacks and Asians. It mainly occurs in fingers, toes and parts under pressure, such as the sole of the foot. It grows fast and can not only spread to the surrounding areas, but also invade deep tissues. At the early stage, it presents patches with irregular edges and quickly turns into blue black or black nodules, which may be accompanied by ulceration. The degree of malignancy is high, and the 5-year survival rate is only 29%.
Acral Melanoma
(Photo source: Dermatology and Venereology (3rd Edition))
four
Nodular malignant melanoma
This is a highly malignant melanoma, which most often occurs in exposed parts of the head, neck, trunk, etc. At the beginning, the skin lesions appear as raised black or bluish black patches and nodules, which quickly grow into mushroom or cauliflower shaped, with ulcers or bleeding, and are prone to early metastasis.
How to distinguish common pigmented nevus
And melanoma?
In order to distinguish melanoma from common pigmented nevus and other pigmented lesions, the National Cancer Institute of the United States proposed the "ABCD" early diagnosis method:
A Asymmetry
Most common pigmented nevi are round or oval, symmetrical; Melanoma is asymmetric.
Border
Common pigmented nevus has clear boundary and smooth surface; Melanoma has many unclear borders and can spread to the surrounding skin. The surface is rough and uneven.
C Color
The color of common pigmented nevus is mostly uniform, which can be light brown, black, brown, and rarely pink; Melanoma may be brown in different shades, occasionally mixed with black, white, blue and red.
D Diameter
Common pigmented nevus is generally less than 5mm, and it is stable for a long time; Most melanomas exceed 5 mm and grow continuously.
It can be seen from the above that if the common pigmented nevus on the body suddenly grows up in a short time, the shape is irregular, the edge is irregular, and the color changes significantly, attention should be paid to it, and timely medical treatment should be taken to determine whether there is any malignant change.
Who is easy to grow melanoma?
Melanoma is related to many factors. The following groups of people are easily favored by melanoma, so pay more attention.
one
People who like to bask in the sun or light
People who are often exposed to the sun for a long time are more likely to have melanoma.
two
A person with fair skin
Melanoma tends to occur in light skinned people. Light skinned people contain less melanin, which is a pigment that can protect the skin from UV damage. However, it should be noted that this does not mean that darker skinned people are not at risk.
three
People whose skin is often injured and irritated
Trauma and stimulation can make benign pigmented skin disease malignant, and about 10-60% of melanoma patients have a history of trauma before onset.
four
People with family history or genetic factors
About 8-14% of melanomas have a family history, such as related susceptibility genes such as CDKN2A. Skin may be more sensitive or damaged.
five
Immunocompromised person
The low immune state is related to the occurrence of melanoma. For example, if you use immunosuppressants or have an immune deficiency disease such as AIDS, the immune system can not effectively remove abnormal cells, which is more likely to cause tumors, including melanoma.
How to prevent melanoma?
As mentioned above, people who are more likely to be attracted to melanoma, let's talk about measures to prevent melanoma.
one
Avoid long-term sun exposure and do a good job of sunscreen
Try to avoid prolonged exposure to the sun. If you go out in strong sunlight, take sunscreen measures. For example, wear protective clothing, hats, sunscreen, etc.
two
Check your skin regularly
Observe whether there are new or changed moles or other abnormal skin growths on your body. If you find any suspicious changes (refer to the "ABCD" method), consult a professional doctor in time.
three
Be aware of your genetic risks
If you have a family history of melanoma, you should have regular skin examinations and genetic tests to see if preventive treatment is needed.
four
develop immunity from disease
Keep good living habits and strengthen your resistance.
conclusion
There is no need to panic about common pigmented nevus, but don't take it lightly. You should always check whether they suddenly grow up, whether the border is blurred, whether the edge is irregular, and whether the color changes. If there is any abnormality, go to the doctor immediately. At ordinary times, we should also pay attention to sunscreen and avoid long-term exposure to the sun; Avoid long-term friction and irritation of pigmented nevus; Develop good living habits, improve immunity, and strive to become a "detested" person of melanoma!
The article is produced by "Science Refuses Rumors" (ID: Science_Facts). Please indicate the source for reprinting.
The cover picture of this article is from the copyright gallery, and reprinting and quoting may cause copyright disputes.
key word:
