Skin malignant tumors, like other tumors, also have primary and secondary, clinically primary is more common and secondary is less common, while the more common primary tumors include basal cell carcinoma, squamous cell carcinoma, carcinoma in situ and eczema-like carcinoma. The incidence rate of domestic skin malignancies (except malignant melanoma) is about 1-2/million, but it seems to have an increasing trend in recent years. Skin cancer generally has the characteristics of low malignancy, slow development, less likely to metastasize distantly, easy to detect and convenient to biopsy, easy to diagnose and treat early, so the prognosis is good.
Basal cell carcinoma: Also known as basal cell epithelioma, erosive ulcer, etc. Metastasis is rare.
Metastases are rare. It is generally divided into four types, and the most common one is nodal ulcer type.
1.Nodular ulcer type: Initially, a small nodule appears on the skin, or it only resembles erythema without significant elevation, or it is slightly nodular, and the skin on the surface is mildly depressed downward. The nodule may gradually expand or crust in the center, followed by ulceration under the scab.
2.Pigmented type: The damage is the same as the nodular ulcer type. It contains more pigment and is similar to malignant melanoma, which is easily misdiagnosed.
3.Sclerotic or fibrotic type: Commonly found on the head and neck, they are hard yellowish or yellowish-white patches, slightly elevated, with unclear borders, resembling scleroderma-like, which can remain intact for a long time and eventually ulcerate.
4. Superficial type: superficial lesions, mostly occurring on the trunk, with one or several infiltrative erythematous patches, with flaking or crusting on the surface and slightly elevated edges or the whole lesion. Similar to eczema or seborrheic dermatitis.
Squamous cell carcinoma: also known as echinocytic carcinoma and epidermolysis bullosa.
There is no obvious difference in clinical manifestation between early stage and basal cell carcinoma. However, squamous cell carcinoma mostly occurs in skin that has been abnormal for a long time, often transformed from keratosis, mucocutaneous leukoplakia or other precancerous diseases. The initial skin damage is often a dry, such as a small papule or nodule, with a dull red surface, rough and uneven, and a closely adherent keratinous material in the center, which is not easy to peel off and will grow keratinous material again after peeling. Later, ulcers may occur in the center and the ulcerated surface will keep increasing, and its development is faster than that of basal cell carcinoma. Some of them look like volcanic vents, with abnormal odor and pain. Some squamous cell carcinomas develop outward and look like cauliflower.
The disease develops faster and is more destructive, and can reach into connective tissue, cartilage, periosteum and bone, and regional lymph node metastasis often occurs, and visceral metastasis can occur in advanced stage. Especially, squamous cell carcinoma of mucous membrane tends to metastasize easily.
Carcinoma in situ: also known as Bowen’s disease, is a kind of intraepidermal squamous cell carcinoma, which is mostly considered as precancerous lesion of dyskeratosis.
Carcinoma in situ generally refers to atypical hyperplasia (severe) within the mucosal epithelium or skin epidermis involving the whole layer of epithelium, but not yet invading the basement membrane and infiltrating downward. Examples include carcinoma in situ of the uterine cervix, esophagus and skin. Even more, infiltration and distant metastasis have not occurred. However, it can further develop into early infiltrating carcinoma, and occasionally the carcinoma in situ can subside. Although the extent of in situ carcinoma is limited, it can be multifocal or involve a larger area without penetrating the basement membrane. Because carcinoma in situ has not formed infiltration and metastasis, it does not meet the characteristics of cancer, so it is not really “cancer”. If it can be detected in time and removed as early as possible or given other appropriate treatments, it can be completely cured.
Eczema-like epithelial carcinoma: Also known as Paget’s disease, it often invades unilateral nipple and areola of women over 40 years old.
The damage often starts from the nipple, mostly unilateral, and is a limited deep red infiltrate with easy surface erosion and eczema-like changes after scratching. It is usually slow, gradually expanding and can affect the entire breast and even the chest wall. The nipples are enlarged and prominent, and the breast has hard nodules as large as chicken eggs. The lesions may also invade the skin outside the breast, such as the vulva, perianal area, axillae, face, lips, nose and other places. It may metastasize to nearby lymph nodes and internal organs. The epidermal changes of extramammary paget disease are the same as those of the breast, but the sweat ducts or hair follicle sebaceous glands are often invaded by paget cells, and most of them have adenocarcinoma of the sweat, or are accompanied by mucosal adenocarcinoma, squamous carcinoma or visceral carcinoma.
What diseases should be distinguished from skin cancer?
Those with similar clinical manifestations include
1.Seborrheic keratosis, also known as senile warts, is common in men over 50 years old, mostly on the face, neck, chest, back and back of the hands, the damage is slightly higher than the skin of round or oval flat warts-like rash, rotten yellow, yellow-brown to coal-black, slightly rough surface, covered with greasy scales scabs.
2, discoid lupus erythematosus: mostly seen in middle-aged men and women, the damage is initially small papules, gradually expanding into plaques, dry in nature, surface keratinous proliferation, dilated hair follicle mouth, containing keratinous emboli spines, with atrophic spots, not forming ulcers, the edges are more congested.
3, keratoacanthoma: middle-aged men are more often, mostly on the face, especially the cheeks and nose, while the extremities and trunk are extremely rare. The damage is a solid hemispherical tumor towering over the skin, resembling a light red acne or a nodule similar to the skin color, with a crater-shaped central depression and a keratinous scab inside.
4.Metastatic skin cancer: metastasis from primary cancer of other organs to skin, usually multiple, with symptoms and signs of primary cancer of other organs at the same time.
5.Pigmented basal cell carcinoma should be differentiated from melanoma.
Treatment methods
I. Surgical treatment
Surgery is the preferred treatment method for skin cancer, and the cure rate can reach 90% to 100% with proper surgical excision. When resecting, basal cell carcinoma should be about 0.5cm away from the tumor, and squamous cell carcinoma should be about 0.5-1cm away from the tumor for skin incision, and sufficient depth is needed to make extensive resection as far as possible. For proven regional lymph node metastasis, lymph node dissection should be performed, but prophylactic dissection is not necessary. When bone or major vessels and nerves are involved, amputation is required. After excision, direct suture or flap repair or skin grafting can be performed.
II. Radiation therapy
Generally, squamous cell carcinoma is moderately sensitive to radiation, and basal cell carcinoma is particularly sensitive to radiation and has higher skin tolerance. It is mainly applicable to skin cancer in special areas not suitable for surgery, elderly and frail, and those with contraindications to surgery (diabetes, kidney and heart diseases, etc.).
Chemotherapy
Most of the patients who have undergone surgery to expand resection or radiotherapy do not need to undergo systemic chemotherapy. For skin cancer patients, systemic chemotherapy is mainly applicable to advanced cases that are not suitable for surgical resection or radiotherapy, and patients who are still suspected of having residual lesions and metastases after surgery and/or radiotherapy.
Prognosis of skin cancer patients
Since skin cancer is mostly confined and located on the surface of the body, it is easy to be detected and has no or little metastasis. If treated timely, most of them do not affect life, and even if a few patients have local recurrence or multiple recurrences, they can still be surgically excised again, and most of them still have good results; since the cure rate can be over 90% with surgical excision alone, postoperative radiotherapy or chemotherapy is usually not performed; radiotherapy or chemotherapy is only used for those with unclean local excision or metastasis.
Preventive measures of skin cancer
1. Avoid excessive sunlight or exposure in daily life, and avoid excessive exposure to ultraviolet rays and x-rays, etc.
2.Avoid longer exposure to coal tar, arsenic agent and chemical carcinogenic agents; occupational contacts should strengthen protection and regular census.
3. Be alert to long-term recurrent ulcers, inflammation, mucosal white spots and long-standing trauma, etc., and conduct regular examination and biopsy or surgical excision when necessary to avoid delaying treatment.
4. For those who suspect malignant change, skin biopsy should be performed as early as possible to achieve early detection and early treatment.