11 June 2021 Author : Rita Ramos Pinheiro Skin cancer , like other malignancies, results from disorders in cell multiplication and life cycle. It is one of the most frequent cancers. Melanoma and skin cancer are not synonymous: Melanoma is a type of skin cancer. It originates in melanocytes, cells that are responsible for skin pigmentation and are found in the deepest region of the epidermis. Melanoma is the most well-known and aggressive skin cancer, although it is not the most frequent; Non-melanoma skin cancer is the name used to refer to other types of skin cancer, which originate in cells of the epidermis other than melanocytes. These are slower-growing and less aggressive tumors. Non-melanoma skin cancer In the group of non-melanoma skin cancer there are two main types: Basal cell carcinoma , the least severe, it represents 65% of cases; Squamous cell carcinoma , which represents 25% of cases; Related to squamous cell carcinoma, actinic keratoses must be mentioned. These are common, pre-malignant skin lesions that have a risk, albeit low, of progression to squamous cell carcinoma. Basal cell carcinoma This is the most common type of skin cancer . Basal cell carcinomas can have different clinical presentations, including: A recent nodule; A red or dark spot; A wound that bleeds and does not heal. It can appear in any part of the body, but predominate in the head, neck, and trunk. Most of these malignant tumors do not cause symptoms . If left untreated, basal cell carcinomas can become invasive in depth, with local tissue destruction. However, they only rarely metastasize to distant tissues or organs. Thus, most of it are non-aggressive malignant tumors , treatable by surgery and that do not put life at risk. Squamous cell carcinoma This type of skin cancer appears mainly on areas of the skin chronically exposed to the sun or in places subject to chronic inflammation, such as burns, chronic wounds or old scars. The clinical presentation is variable including: A red nodule, hard with a thick crust or scale; A pink plate with scale; An ulcer (wound). Squamous cell carcinomas may not cause symptoms, local pain or bleed . They can eventually metastasize , endangering life. Local recurrence and metastasis to lymph nodes or other organs can occur in a minority of patients, especially those who have a more advanced disease. Actinic keratosis Actinic keratosis are discreet rough or scaly patches or plaques that appear in areas more exposed to sun damage over the course of the years. They are very common in exposed areas of the skin and can be present in considerable numbers. When these are removed by the patient it can almost disappear, but reappear, days later, in the same place. Actinic keratosis are considered pre-malignant lesions with low risk of progression into squamous cell carcinoma. Its location in the mucosa of the lower lip, which is called actinic cheilitis, has particular characteristics, due to the potential for malignant transformation. Causes of non-melanoma skin cancer The most common cause of non-melanoma skin cancer is exposure to ultraviolet radiation , either from the sun or from other sources. This radiation causes lesions of the epidermis cells, which begin to multiply in an uncontrolled way. People with increased risk of developing non-melanoma skin cancer are: Light-skinned and with a tendency to burn (scalding); Have habits of sun exposure throughout their lives, whether in a leisure or professional context (outdoor workers), Have a previous diagnosis of skin cancer; Immunocompromised and transplanted. Except for some rare syndromes, basal and squamous cell carcinomas are generally not hereditary. Treatment Most non-melanoma skin cancers have slow growth and a simple surgical treatment . However, early diagnosis is essential . Therefore, although these types of cancer have a variable clinical presentation, it is very important to seek for medical care when a change in a lesion or sign is detected, such as enlargement, bleeding, lack of healing or change in appearance. Patients with a personal history of skin cancer are at an increased risk of developing new skin tumors, so they should keep a regular follow up in a dermatology and do their self-surveillance. When non-melanoma skin cancer is diagnosed at an early stage, surgical treatment involves removing the tumor and a healthy skin margin, usually with local anesthesia. Treatment can be more complex: For some subtypes of tumors and depending on their location; In the most advanced cases, when there is a long delay between the appearance of the tumor and the search for medical care. Skin cancer prevention Sun protection is essential for the prevention of any type of skin cancer, and the following general measures must be adopted: Avoid direct sun exposure between 11 am and 5 pm; Apply a photoprotective cream (protection factor 50+) regularly in exposed skin areas and repeat the application every 2 hours, or more often if you bathe or sweat; Wear a hat and clothing that provide additional protection to the photoprotector; Do not use solariums. Meet the dermatology team from Hospital da Luz network and book your consultation The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
