Skin Cancer
What are the causes and symptoms of skin cancer? Information on the prevention and treatment of different types of tumors.
Symptoms and Causes
Skin cancer is an abnormal growth of the cells that make up the skin. Although it is one of the most common cancers worldwide, it can be prevented and, in most cases, cured.
This type of cancer begins in the epidermis, which is the outer layer composed of three types of cells. Depending on which cells are affected, we distinguish the following types:
- Basal cell carcinoma: The most common type, originating in the lower layer of the epidermis. It typically affects areas exposed to the sun, such as the face or neck. Since it develops slowly, metastasis is rare.
- Squamous cell carcinoma: Affects the flat surface cells that continuously regenerate, leading to abnormal growth. It commonly presents as patches, warts, itching, or scabs. If detected early, it has a high cure rate.
- Melanoma: Affects melanocytes, the cells responsible for producing melanin, which gives skin its pigment. It usually appears as changes in existing nevi (pigmented lesions). Although less common, it is more aggressive than the previous types.
In recent years, the incidence of skin cancer has increased, likely due to sun exposure habits. For this reason, specialists emphasize the importance of prevention and early diagnosis.
Symptoms
Skin cancer symptoms vary depending on the type:
- Basal cell carcinoma:
- Small, shiny nodules.
- Scabs.
- Open ulcers.
- Reddish or pinkish growths.
- Flat, scar-like plaques (morpheaform).
- Itching.
- Squamous cell carcinoma:
- Reddish patches.
- Thick, irregular, scaly growths.
- Scabs.
- Open sores.
- Melanoma: Uncontrolled growth of pre-existing pigmented lesions (moles or warts). It is considered a risk if it follows the ABCD rule:
- A: Asymmetry.
- B: Irregular borders.
- C: Color variation within the same nevus.
- D: Diameter greater than 6 millimeters.
Causes
The main causes of skin cancer include:
- Genetic predisposition.
- Overexposure to ultraviolet radiation, either from the sun or tanning lamps.
- Contact with chemical agents such as arsenic, tar, or coal.
- Severe skin injuries, such as burns or infections.
Risk Factors
Certain factors increase the risk of developing skin cancer, including:
- Spending a lot of time outdoors without sunscreen.
- Using tanning beds.
- Having fair skin (low pigmentation) or being albino (lack of melanin).
- Working in environments exposed to chemicals like tar, arsenic, coal, paraffin, or petroleum and its derivatives.
- Having undergone radiation therapy or being exposed to radiation.
- Having scars from severe burns.
- Receiving psoriasis treatment with psoralens and ultraviolet light.
- Suffering from xeroderma pigmentosum, a hereditary disease that makes the skin and mucous membranes more sensitive to ultraviolet radiation.
Complications
Skin cancer can spread to nearby organs, such as the eyes or nose, or metastasize to more distant areas like the lungs or brain, particularly in cases of melanoma.
Prevention
To prevent skin cancer, it is advisable to take the following precautions:
- Use high-factor sunscreen daily.
- Wear sunglasses and a hat.
- Avoid sun exposure during peak hours.
- Do not use artificial tanning beds.
- Regularly monitor the appearance of moles and warts.
Which Doctor Treats Skin Cancer?
Skin cancer is diagnosed and treated by specialists in dermatology, medical oncology, radiation oncology, or plastic surgery.
Diagnosis
To diagnose skin cancer, the following tests are commonly performed:
- Visual examination: The overall condition of the skin is assessed, with a particular focus on nevi to detect potential alterations that may indicate cancerous cells.
- Skin biopsy: A small tissue sample is taken from the suspicious area and analyzed in the laboratory for signs of malignancy.
- Dermatoscopy: A technique used to analyze skin lesions. A dermatoscope is used to magnify and illuminate the area, allowing for a detailed examination of the characteristics of nevi.
Treatment
The treatment for skin cancer depends on the type and characteristics of the lesions (location, size, and depth). The most commonly used procedures include:
- Cryotherapy: Liquid nitrogen is applied to freeze malignant lesions.
- Photodynamic therapy: A photosensitizing medication (which activates upon exposure to light) is applied locally and then activated using a laser or LED device to eliminate cancerous cells.
- Excisional surgery: A surgical procedure in which the malignant tissue and a margin of healthy surrounding skin are removed.
- Mohs surgery: Used for more extensive or recurrent cancers. In this procedure, the lesion is removed layer by layer, ensuring that no healthy cells are unnecessarily excised.
- Radiotherapy: Ionizing radiation is directed at the cancerous lesion, usually for areas that could not be surgically removed.
- Chemotherapy: Typically used as a last resort when other options have not been effective, as it is not as successful as in other types of cancer. Chemical medications such as dacarbazine, temozolomide, or cisplatin are injected to reduce malignant cells.
