There are more or less some moles in human body, and many people are used to them in daily life, and even call the moles that grow between the beauty bows as “beauty moles”; some people often use laser surgery to remove moles because too many moles on their bodies affect their beauty; some people worry that the hard nodes formed after trauma to hands and feet will become cancerous. Some of these people often use scissors and blades to flatten them, etc. A small percentage of these people will suffer from malignant tumor – melanoma, which is what we call malignant melanoma.
The incidence of this disease is relatively high in Europe and the United States, while the incidence in China is relatively low, only 0,8/100,000, but in recent years, due to air pollution and other factors, resulting in its incidence is on the rise, but due to the lack of awareness of its seriousness among doctors and patients, it is usually too late when it is diagnosed, coupled with the treatment is not standardized, the treatment effect of melanoma is extremely unsatisfactory. Therefore it should be given enough attention.
What is malignant melanoma?
Melanoma, is a malignant tumor originating from melanocytes, which are differentiated from melanocytes of neural tube pluripotent stem cells. In humans, melanocytes are located at the junction of the epidermis and dermis of the skin. Unlike other epidermal cells, melanocytes rarely proliferate under physiological conditions, and their survival, migration, and differentiation are regulated by specific genes and a series of molecules expressed on their own and neighboring cell surfaces and in the extracellular matrix. Most believe that when environmental factors cause an imbalance in these genes and molecular regulation, melanocytes become malignant and become malignant melanoma, or malignant black. The malignancy of these tumors is high, with cutaneous malignant melanoma accounting for only 4% of all malignancies originating in the skin, but its lethality rate is 79%. It is prone to distant metastasis and has a poor prognosis.
Is the incidence of malignant melanoma high?
Malignant melanoma predominates in white people. QueenS-Land in Australia is known as a region with a high incidence of malignant melanoma in the world. Malignant melanoma accounts for 1 to 3 percent of all malignancies, and melanoma is one of the fastest growing tumors, with the incidence increasing by about 3 percent per year, and its incidence has increased approximately six-fold in the past 50 years. Survey data on malignant melanoma in the United States show that about 82%-85% of patients initially diagnosed with melanoma exhibit limited disease (AJCC stage I or II), 10%-13% exhibit regional metastases (AJCC stage III), and distant metastases (AJCC stage IV) occur in 2%-5% of patients. No data are available in this area in China, but due to the lack of awareness of the severity of melanoma among doctors and patients, many patients are already in the middle to late stages when they are diagnosed, and the prognosis is extremely poor. The prognosis of advanced melanoma is related to the different metastatic sites and the number of metastatic organs. According to statistics, the median survival of patients with distant cutaneous lymph node metastases (stage M1a) is 15 months, lung metastases (stage M1b) is 8 months, liver and brain metastases in M1c is 4 months, and bone metastases is 6 months. The overall median survival was 5 months, with a 2-year survival rate of 15% and a 5-year survival rate of about 5%.
Why do people get malignant melanoma?
Most malignant melanoma occurs due to the malignant transformation of benign nevi into malignant melanoma caused by repeated rubbing and scratching, inappropriate excavation and drug erosion, etc. It is reported that 84% of malignant melanoma comes from benign nevi, as the nevi start to be relatively small many patients do not notice some subtle changes in the nevi at the beginning of the disease. People who work outdoors and receive more ultraviolet rays are prone to malignant melanoma of the skin. In addition, the incidence of melanoma is higher in people who live in places with serious environmental pollution. In terms of age, melanoma occurs mostly in middle-aged and elderly people, and very rarely in prepubertal age. In addition, women during pregnancy or childbearing age can cause malignant melanoma to develop rapidly suggesting that the disease is endocrine related.
Where does malignant melanoma usually occur?
Melanoma can occur in any part of the body, but usually occurs in the skin, accounting for 95% of cases. Malignant melanoma of non-skin origin, such as those originating in the eyes, mucous membranes (including the nose, respiratory tract, and gastrointestinal tract mucosa), and the reproductive system, account for 4% to 5% of all melanomas. The clinical and biological characteristics and prognosis of melanoma of non-skin origin at specific sites are significantly different from those of skin origin. Unlike malignant melanoma of non-skin origin, which is prone to regional lymph node metastasis, malignant melanoma of non-skin origin is more likely to disseminate hematogenously to the liver, lung, brain, and skin, and has no significant association with sun damage, family history, family susceptibility genes, or nevus malignancy. Progression is more rapid and the prognosis is worse.
What are the manifestations of malignant melanoma?
Melanoma occurs more frequently in middle-aged and elderly people, more often in men than women, and is more likely to occur in the feet of the lower extremities, followed by the trunk, head and neck, and upper extremities. The symptoms are mainly fast-growing melanin nodules, which may initially appear as melanin deposits on normal skin or pigmented nevi with increased pigmentation and deepening of black color, followed by expanding lesions, increasing hardness and itching. Melanoma lesions may be raised, plaque, nodular, myxoid or cauliflower shaped, or subcutaneous nodules or masses if they grow under the skin, or stellate dark spots or nodules if they spread to the surrounding area. In melanoma patients, regional lymph node metastasis often occurs, and many patients often present to the doctor with enlarged regional lymph nodes. In advanced stages, tumors metastasize from the bloodstream to organs such as the lung, liver, bone and brain. A series of corresponding organ invasion symptoms are exhibited.
What tests should be done for malignant melanoma?
Whole body physical examination, blood sampling, color ultrasound of whole body lymph nodes, relevant physical examination and imaging examination.
What is the prognosis of malignant melanoma?
The prognosis is affected by the depth of tumor infiltration, lymph node metastasis, location of the lesion, age and gender, and surgical procedure. The prognosis of melanoma of mucosal origin is worse than that of melanoma of cutaneous origin. Rare juvenile malignant melanoma has a better prognosis. The prognosis of malignant melanoma under 5 years of age has been reported to be better than that of older patients, but some believe that the age factor has little effect on prognosis.
How should malignant melanoma be treated?
The principles of treatment for malignant melanoma vary with the clinical stage. For limited lesions, surgical resection is the primary treatment principle for melanoma, and approximately 50-90% of patients can survive long-term after surgical removal of the primary tumor site. In patients with advanced metastatic malignant melanoma, although some patients with limited metastases can achieve local control of the tumor and prolong survival after local treatment (surgical resection and radiotherapy, etc.), the vast majority of patients with metastatic melanoma need to receive systemic systemic therapy. However, because melanoma cells are not sensitive to chemotherapy, there is no effective treatment for metastatic melanoma. Many clinical studies have attempted to find new effective treatments, such as biologic therapy, biologic chemotherapy combined with chemotherapy, and new targeted drugs, etc. Although the efficiency has been improved, they still have not shown an overall survival benefit, so for advanced metastatic melanoma there is still Therefore, an optimal and effective treatment for advanced metastatic melanoma has not yet been established. Systemic chemotherapy is currently the only option. Since most chemotherapeutic agents cannot cross the blood-brain barrier to control intracranial lesions, chemotherapy is mainly used to treat patients with non-cerebral metastases of metastatic melanoma, while local treatments such as surgical resection, whole-brain radiotherapy or stereotactic radiotherapy are mainly used for patients with brain metastases. In addition, for some advanced patients, systemic treatment is feasible for metastases with radioactive particle implantation if the tumor is in complete/partial remission. In addition, for patients with extensive subcutaneous metastases, local arterial infusion chemotherapy is feasible.
What diseases are easily confused with malignant melanoma?
1. benign junctional nevus: microscopically seen as benign large nevus cells with no heterogeneous cells, growing only in the dermis, and its inflammatory reaction is not obvious.
2. Juvenile melanoma: it occurs as a slow-growing round nodule on the face of children, with polymorphic cells and nuclear division, and the tumor cells do not infiltrate into the epidermis, and no ulceration is formed on the surface of the tumor.
3.Cellular blue nevus: it occurs in the buttocks, caudal sac and lumbar region, with pale blue nodules, smooth and irregular surface, dendritic dark black cells and large prismatic cells can be seen microscopically, and the possibility of malignant transformation should be considered when there is nuclear division phase or necrotic area.
4.basal cell carcinoma: it is a malignant tumor of epithelial cells, infiltrating from the basal layer of epidermis to the deep, surrounded by lamellar columnar or cuboidal cells, with deep staining of cancer cells, without certain arrangement, and cancer cells may contain melanin.
5.Sclerosing hemangioma: epidermal hyperkeratosis, dermal papillary proliferation, dilated capillaries often surrounded by downward extending epidermal protrusions, appearing like intraepidermal hematoma.
6.Ageing nevus: seen as a warty nevus on the body surface of the elderly, with hyperkeratosis of the epidermis, partial thickening or atrophy of the granular layer, hypertrophy of the spinous layer, intact base layer, also with increased pigmentation, proliferation of dermal papillae, and a papilloma-like proliferation in appearance.
7, seborrheic keratosis: lesions also appear papillomatous hyperplasia subepidermal boundaries are clear, keratinization is incomplete, the granular layer first thickens, then thins or even disappears, the hyperplastic epidermal cells may have a small or more melanin.
8, subxiphoid hematoma: most have a history of corresponding trauma, microscopically dry blood cells, there may be epithelial fibroblast proliferation.
9. some atypical melanoma: it appears as a subcutaneous nodule at the extremity with a color similar to the surrounding normal skin, which is easily misdiagnosed as boils, folliculitis, etc.
How should malignant melanoma be prevented?
Perform regular self-examination of the skin. Avoiding sun exposure as much as possible and using a sunshade are important primary preventive measures. Education of the general public and professionals, especially for those at risk, should be strengthened. It is more important to improve the “three early stages”: early detection, early diagnosis and early treatment.
For pigmented nevi that occur in areas prone to friction, biopsies should be taken for pathological examination. For example, children with large hairy nevi in the waist, which are often rubbed and squeezed by the belt, should be removed as early as possible. If it is difficult to remove all of them at once, the main part of the nevus can be removed in the middle of the nevus before it becomes malignant, and then both sides can be sutured. After the skin around the service is pulled loose, the rest of the mole can be removed until all of it is removed. In order to prevent malignant change, each excised specimen must be sent to pathological examination, and if there is malignant change, all of them should be excised, and then implantation should be performed.
It is not advisable to stimulate the nevus with needle picking, corrosive drugs or thorough freezing as well as laser, which are dangerous methods. This is because nevi often become malignant due to traumatic stimulation. It has been reported that malignant changes occurred due to incomplete freezing at one time. In addition, malignant melanoma is also associated with external stimulation. If the mole is removed for cosmetic reasons, it should be removed in one go. Freezing combined with excision is aimed to be done at one time. Split excision is not allowed, and the excised specimen should be sent for pathological examination.
What are the signs of malignant pigmented nevus that need to be alerted?
To determine whether a pigmented nevus is malignant we summarize the ABCD rule, namely
1. the mole becomes irregular, or even ulcerated and bleeding.
2. the boundary of the mole becomes unclear
3. the color of the mole, etc., changes.
4.The mole gradually becomes larger.
With the improvement of social and economic level, people’s understanding of the disease is becoming more and more comprehensive, and the level of medical technology is also changing rapidly, we also advocate “early detection, early diagnosis, early treatment” emphasizing tertiary prevention in the prevention and treatment of melanoma. We believe that with the joint efforts of patients and medical staff, the level of melanoma diagnosis and treatment will create a brand new situation!