Table Of Content


Our skin is the largest organ of the body. It helps to control body temperature and protects the body from injury and infection. It is made up of three layers such as epidermis, dermis, and hypodermis. The skin also produces vitamin D and stores fat and water. Normally skin rejuvenation happens where new skin develops when existing cells die or are destroyed. When this process fails, a rapid increase of cells (some of which may be aberrant cells) occurs which could be malignant or benign.

Skin cancer is a condition which occurs when the skin cells proliferate and grow in an unregulated manner.

How Does Skin Cancer Develop?

Skin cancer develops as a result of mutations occuring in the DNA of the skin cells. These mutations lead to uncontrollable growth and the formation of a mass of cancerous skin cells.

Types Of Skin Cancer

In general, skin cancer is categorized broadly into three types:

  • Basal cell carcinoma
  • Squamous cell carcinoma
  • Melanoma

Basal cell carcinoma: Basal cells located in the lower epidermis. It can be seen anywhere on the skin. However, it usually appears on the head and neck. It primarily results from sun exposure or manifests in patients who have radiation therapy as children. This type of skin cancer spreads to other body parts and grows slowly.

Squamous cell carcinoma: Most of the epidermis contains squamous cells, which are flat, scale-like cells. It can be found in numerous areas of the skin because it is mainly caused by sun exposure. It can also be acquired by exposure to x-rays and chemicals. Squamous cell carcinoma appears in the lips and the skin around the mouth, anus, and vagina.

Melanoma: Melanoma is scattered cells that exist where the epidermis meets the dermis. These cells generate melanin pigment, which gives skin color. The majority of melanomas are either black or brown, although some are also red, pink, purple, or skin-colored. The most aggressive kind of skin cancer is melanoma, which begins in melanocytes.

Rare Types Of Skin Cancer

Merkel cell carcinoma is a rare kind of skin cancer that is extremely aggressive or rapidly developing. It starts in the hair follicles and the hormone-producing cells under the skin. It typically affects the head and neck, otherwise known as neuroendocrine carcinoma.

Sebaceous gland cancer affects the glands that create the skin's natural oils. This cancer commonly affects eyelids but can develop anywhere in the body. Sebaceous carcinoma is more aggressive skin cancer which spreads quickly.

Kaposi sarcoma is often associated with HIV. However, it can also develop in persons who do not have HIV. This cancer develops in the cells that line the skin's blood vessels and lymph nodes.

T cell lymphoma starts with white blood cells (T lymphocytes). Normally, these cells assist your body's immune sys

Stages of Skin Cancer

The TNM staging tool is the common tool used in determining the stages of skin cancer. Based on the types of skin cancer, the staging is divided.

Stages of Basal Cell Carcinoma:

  • Stage 0 (Carcinoma in situ): In this in situ stage, the tumor is found only in the epidermis and has not metastasized (spread) to the dermis.
  • Stage I: Tumor is found in 2 cm or less, has not invaded nearby lymph nodes or organs, and has no more than two high-risk features.
  • Stage II: The tumor is more than 2cm and spreads to the epidermis into the dermis. It does not spread outside the skin, cartilage, muscle, or bone and has high-risk features.
  • Stage III: In this stage, cancer invades areas below the skin, muscle, bone, cartilage, or lymph nodes but has not spread to nearby organs.
  • Stage IV: The tumor may be any size and has metastasized to one or more lymph nodes, bones, or other organs like lungs and brain, or perineural invasion of the skull base or the skeleton.

Stages of Squamous Cell Carcinoma:

  • Stage 0 (Carcinoma in situ): Tumor in this stage is only found in the epidermis and has not spread to the dermis. This stage is otherwise known as Bowen's disease of the skin, which appears as pink or red scaly patches that are often exposed to the sun.
  • Stage I: In this stage I, the tumor size is less than 2 cm, has not invaded nearby lymph nodes or organs, and has one or fewer high-risk features.
  • Stage II: In this Stage II, the tumor is larger than 2 cm, has not spread to nearby organs or lymph nodes and has high-risk features.
  • Stage III: In stage III, the tumor has spread into the nearby lymph node or facial bones but not to other organs.
  • Stage IV: In this stage, cancer may be any size and has metastasized to more than one lymph node that is greater than 3 cm and may have spread to bones or other organs in the body.

Stages of Melanoma:

  • Stage 0: In this stage, melanoma cells are found only in the epidermis (outer layer of skin ). This stage of melanoma has not spread to lymph nodes and other parts of the body.
  • Stage I: In this stage, tumors are found in both the dermis and epidermis. It has not reached lymph nodes or other body parts.
  • Stage II: In this Stage II, tumors are found in the epidermis and dermis. Melanoma risk is higher than stage I due to the depth of the tumor or the presence of ulceration. It has not spread to distant body parts or lymph nodes.
  • Stage III: In this stage, cancer has spread to one or more regional lymph nodes or has established an in-transit or satellite metastasis, which is a deposit of melanoma in the skin or dermis along the lymphatics before reaching a lymph node.
  • Stage IV: Stage IV refers to a tumor that has spread to more distant parts of the body from the primary tumor site and regional lymph nodes. The most common metastatic sites are distant skin and lymph nodes, followed by the liver, lungs, brain, bone, or intestines.
    Stage IV is further classified based on the location of distant metastasis:
    ▪ M1a: Cancer has only metastasized to distant skin or soft-tissue sites.
    ▪ M1b: Cancer has spread to the lung.
    ▪ M1c: Cancer has spread to any other location that does not involve the central nervous system.
    ▪ M1d: Cancer has spread to the central nervous system, including the brain, spinal cord, or cerebrospinal fluid.

Causes and Risk Factors Of Skin Cancer

Fair skin or complexion: Everyone has a chance of getting skin cancer, regardless of skin tone. People with light-colored skin, blue eyes, red hair, and freckles are more likely to acquire skin cancer. People whose skin tends to burn rather than tan are also at higher risk.

A history of sunburns: Your risk of skin cancer increases if you experience one or more blistering sunburns. Adult sunburns are another risk factor.

Excessive sun exposure: Sun exposure is the primary cause of most skin cancer. It could be long-term exposure or short periods of extreme sun exposure and burns. Sunlight's ultraviolet rays harm the DNA of skin cells. Recreational suntanning should be avoided to lower the chance of developing skin cancer.

Sunny or high-altitude climates: People who live in bright, warm climates are more likely to be exposed to sunlight than those who live in colder climates. Living at higher altitudes exposes you to more radiation because where the sunlight is the brightest.

Moles: Skin cancer risk is higher in people with numerous or abnormal moles. These abnormal moles have an uneven appearance and are typically larger than normal moles, and develop into cancer.

Precancerous skin lesions: Your chance of skin cancer can increase if you have actinic keratoses. These precancerous skin growths appear as rough, scaly patches occurring brown to dark pink color. They typically appear on the face, head, and hands of fair-skinned people with sun-damaged skin.

A weakened immune system: Skin cancer is more likely to occur in people with compromised immune systems. It includes persons with HIV/AIDS and those taking immunosuppressant medications after an organ transplant.

Exposure to radiation: Radiation therapy given to the patients for skin diseases including eczema and acne may increase the risk of acquiring skin cancer.

Exposure to certain substances: Exposure to certain substances, such as arsenic, may increase your risk of skin cancer.

A family history: You may be at a higher risk for skin cancer if one of your parents or a sibling has skin cancer.

A personal history: If you developed skin cancer before, you are at risk of getting skin cancer again.

Signs and Symptoms Of Skin Cancer

Signs and symptoms of various types of skin cancer include:

Basal cell carcinoma:

  • Bleeding or scabbing sores
  • An open sore that bleeds or crusts.
  • Pink, red, pearly white, or translucent bump

Squamous cell carcinoma:

  • A rough, scaly lesion that might itch, bleed and become crusty.
  • A firm pink or red nodule.


  • Changes in the size or color of the mole
  • A painful lesion that itches or burns
  • A brown-pigmented patch or bump.
  • Dark lesions on your fingertips, palms, soles, or toes, or on mucous membranes lining your mouth, nose, vagina, or anus

Find out if a mole or freckle might be melanoma by using the "ABCDE" method.

  • Asymmetry: The mole is an irregular shape.
  • Border: blurry or irregularly shaped edges.
  • Color: mole with dark spots or uneven shading.
  • Diameter: larger than a pencil eraser (6 mm).
  • Evolution: changing in shape, color, or size. (This is the essential sign.)

Skin Cancer Screening

Screening tests are performed when you are healthy and have no signs or symptoms of the disease. They can help in the early detection of cancer, so successful treatment can begin. Skin cancer screening methods include visual self-examination by the patient and clinical examination by a medical professional. During skin examination, the healthcare provider will examine your skin to check for birthmarks, moles, or other pigmented regions that look abnormal in size, color, shape, or texture.

Skin Cancer Screening

A skin cancer diagnosis is usually made after any symptoms appear or if screening tests indicate cancer risk. The type of diagnostic tests varies depending on the type of cancer, signs and symptoms, age, general health, and the results of the previous medical tests.

Diagnostic procedures and tests for Skin cancer include:

Physical examination of the skin: Your doctor may examine your skin for any abnormal mole, growth or changes in your skin.

Skin biopsy: Your physician may remove the suspicious-looking skin for laboratory testing. A biopsy can identify whether you have skin cancer and, if so, what form of skin cancer you have.

Skin biopsies can be of four primary types:

  • Shave biopsy: A sterile razor blade is used to shave-off the growth that appears abnormal.
  • A punch biopsy: It is also known as a trephine biopsy, is used to remove a circle of tissue from an abnormal-looking tumor.
  • Incisional biopsy: A growth is partially removed using a scalpel.
  • Excisional biopsy: The entire growth is cut off using a scalpel.

Imaging tests: Imaging tests like CT scans, X-rays, and MRI check whether cancer cells have spread to bones and internal organs. These tests are not required for people with early-stage melanoma. In skin cancer, the following imaging tests are used:

  • Chest x-ray: This test may determine whether the melanoma has spread to the lungs.
  • Ultrasound: It employs sound waves to create images of the inside of your body on a computer screen. The lymph nodes close to the tumor may be examined with this technique, particularly if it's unclear from a physical exam if they are enlarged.
  • Computed tomography (CT) scan: This examination can reveal any swollen lymph nodes and any suspicious areas on the liver or lungs, indicating melanoma's spread.
  • Magnetic resonance imaging (MRI) scan: MRI scans provide detailed images of your body using radio waves and strong magnets rather than x-rays. It can be useful in examining the brain and spinal cord.
  • Positron emission tomography (PET scan): A PET scan can assist in determining whether cancer has progressed to the lymph nodes or other body parts. It works well in patients with more advanced melanoma stages.

Blood test: Generally blood tests are not used to diagnose melanoma. But doctors check the level of lactate dehydrogenase (LDH) in the blood. A high LDH level indicates that the melanoma has spread to other parts of the body.

Skin Cancer Treatment

Depending on the lesions' size, type, depth, and location, the doctor may recommend treatment options. The major treatment options for skin cancer include surgery, radiation therapy, chemotherapy, photodynamic therapy, immunotherapy, and targeted therapy.

Surgery is a medical procedure in which the tumor and surrounding tissue are removed. A simple surgical procedure can quickly and effectively remove many cancerous tumors from the skin.

Types of Skin Cancer Surgery include:

  • Simple excision: In this procedure, the tumor and some surrounding normal tissue are removed from the skin.
  • Shave excision: A tiny blade removes the aberrant area from the skin's surface.
  • Mohs micrographic surgery: This method treats basal and squamous cell carcinomas. Your healthcare professional removes the skin growth layer by layer and checks each layer under a microscope until no abnormal cells remain. This method removes malignant cells without removing too much healthy skin from the surrounding area.
  • Curettage and electrodesiccation: This method is used to treat basal cell and squamous cell cancers of the skin. This procedure scrapes the tumor with an instrument with a sharp, looping edge to eliminate cancer cells. The leftover cancer cells are subsequently eradicated from the area using an electric needle.
  • Cryosurgery: This technique uses an instrument to freeze and eradicate aberrant tissue-such as cancer-in situ. It is otherwise known as cryotherapy.
  • Laser surgery: In this type of surgery, a laser beam, which is a concentrated, narrow beam of light, is used as a knife to cut through tissue or to remove a surface lesion like a tumor.
  • Dermabrasion: This surgery involves removal of skin's top layer by rubbing away skin cells with a revolving wheel or small particles.

Radiation therapy involves using high beams of X-rays or protons targeted toward the cancer cells to destroy them. External beam radiation therapy is usually used to treat skin cancers that use the equipment outside the body to send radiation toward the cancer area.

Chemotherapy treatment uses medication to destroy cancer cells. It is used when surgery and other conventional treatments cannot remove the tumor entirely.

Types of chemotherapy for skin cancer include:

  • Topical chemotherapy: 5-fluorouracil (5-FU) is a topical chemotherapy medication that is in a cream form, and it can be applied directly to the skin's surface, which addresses precancerous skin conditions.
  • Systemic chemotherapy: This treatment is used for basal cell or squamous cell carcinomas. Drugs like cisplatin, doxorubicin, mitomycin, and 5-fluorouracil may be recommended for this use.

Photodynamic therapy: In this therapy, medicine is applied to your skin, which is subsequently activated by a blue or red fluorescent light. While leaving normal cells alone, photodynamic therapy kills precancerous cells.

Immunotherapy uses our disease-fighting immune system to fight cancer. It can identify and destroy any abnormal cells and prevent some cancerous growth. It is used to treat advanced melanoma (stage 4).

Targeted therapy can identify and target the genes or proteins involved in cancer cell proliferation and multiplication, halting cancer progression. It helps in preventing or slowing the spread of advanced melanoma.

Skin Cancer Prognosis

According to the National Cancer Institute, the prognosis is defined as - "The likely outcome or course of a disease; the chance of recovery or recurrence."

Skin cancer prognosis depends upon various factors such as:

  • Location of tumor
  • Size and depth of tumor
  • Recurrence
  • Type or sub type of tumor
  • Grade
  • Tumor borders
  • Stage of cancer

Prevention Of Skin Cancer

The following preventive measures can be used to prevent skin cancer includes:

  • Avoid direct sunlight exposure between 10:00 a.m. and 4:00 p.m., or seek shade during this time.
  • Use broad-spectrum sunscreen all over the year that has an SPF of 30 or higher and protects against UVA and UVB rays.
  • One ounce (2 tablespoons) of sunscreen should be applied to your entire body for at least 30 minutes before going outside.
  • Reapply every 2 hours, or after heavy sweating or being in the water.
  • Use a lip balm with an SPF of 15 or more.
  • Wear hat and other sun-protective clothes, such as darker colors and closely woven fabrics, when you are outside in the sun. For more effective sun protection, choose clothing with an ultraviolet protection factor (UPF) label.
  • Wear UV-protective sunglasses.
  • Refrain from sunbathing for fun.
  • Avoid tanning beds, sunlamps, and tanning salons.
  • Be aware that several common prescriptions and over-the-counter medications, including antibiotics, can make your skin more sensitive to sunlight.
  • Keep infants away from the sunlight. Apply sunscreen to infants who are older than six months.
  • Do regular skin self-examination to detect skin cancer early.

Skin Cancer FAQs

1. What is the main cause of skin cancer?

Exposure to Ultraviolet rays (UV rays) is the primary cause of skin cancer because it causes DNA damage and genetic mutations, which lead to skin cancer.

2. Is skin cancer curable?

Yes, skin cancer has a good chance of being cured if the signs and symptoms are detected and treated early. If you observe any changes in the size, color, or shape of skin growths on your skin, or if you find any spots, consult a dermatologist.

3. How can I determine whether my skin cancer is melanoma?

You can use the ABCDE method to evaluate whether an abnormal growth on your skin might be melanoma:

  • Asymmetry: The mole shape is irregular.
  • Border: The margin is uneven or notched rather than smooth.
  • Color: The mole has dark spots or uneven shading.
  • Diameter: The spot is bigger than the size of a pencil eraser.
  • Evolving or Elevation: The spot's size, shape, or texture changes.

4. Is immunotherapy an option for me?

Immunotherapy medications or checkpoint inhibitors have been approved to treat certain types of melanoma and Merkel cell cancer. These medications prevent the chemical signals that cancer cells use to evade the immune system.

5. Is skin cancer becoming more prevalent?

Yes, skin cancer has been gradually and rapidly increasing over the years. Non-melanoma skin cancer affects one in two men and one in three women. Once a patient has non-melanoma skin cancer, there is a higher risk of acquiring other skin cancers too.

6. How does UV radiation affect skin cancer?

UV radiation consists of UVA and UVB rays that can penetrate the skin and permanently destroy the cells beneath:

  • Deep skin penetration of UVA results in immunological suppression, photoaging, and genetic cell damage.
  • UVB damages the cells and causes sunburn by penetrating the top layer of the skin.
  • If the body cannot reverse this sun damage, the cell will start to divide and grow aggressively, leading to skin cancer.

7. What are my skin cancer treatment options?

Surgery, radiation therapy, chemotherapy, photo dynamic therapy, Immunotherapy and targeted therapy are the various treatment options for skin