Actinic keratosis (AK) is a skin condition that appears as rough, scaly patches or spots on areas of skin that have been exposed to the sun for prolonged periods of time. It is considered a precancerous lesion, as it can sometimes develop into a type of skin cancer called squamous cell carcinoma. AKs are most commonly found on the face, ears, neck, hands, and arms. They are often treated with cryotherapy (freezing), topical chemotherapeutic creams, photodynamic (Blu-U) light therapy, or medium-depth chemical peels.

Basal cell carcinoma (BCC) is the most common type of skin cancer. It develops in the basal cells, which are cells located at the bottom of the skin's outermost layer. BCCs usually appear as small, skin-colored to pink bumps or nodules that may be pearly or waxy in appearance. They can also look like open sores that don't heal, scaly patches, or raised, reddish patches.

Treatment options for BCC include:

1. Surgical excision: removal of the cancerous tissue.
2. Mohs surgery: a specialized surgical technique that removes the cancerous tissue in a small disk while preserving as much healthy tissue as possible followed by pathologic evaluation of 100% of the margins.
3. Radiation therapy: using high-energy beams to destroy cancer cells.
4. Topical medications for non-aggressive types: such as 5-fluorouracil (5-FU) or imiquimod.

It's important to see a dermatologist for proper diagnosis and treatment of BCC. Early detection and treatment of skin cancer can increase the chances of a successful outcome.

Melanoma is a type of skin cancer that starts in the cells that produce pigment (melanocytes). It is more aggressive and can spread to other parts of the body if not treated early. It can develop from an existing mole or from normal-looking skin. Signs of melanoma include a new mole or a change in an existing mole, such as an increase in size, color, or irregularity of shape. Treatment for melanoma typically involves surgical removal of the affected area of skin by either a dermatologist or an oncologic surgeon. A dermatologist will recommend the most appropriate treatment, which often includes a biopsy to confirm the diagnosis.

Squamous cell carcinoma (SCC) is a type of skin cancer that begins in the squamous cells of the outer layer of skin. SCC is the second most common type of skin cancer, after basal cell carcinoma, and is often caused by exposure to the sun or other sources of ultraviolet (UV) radiation. Squamous cell carcinoma typically appears as a rough, scaly patch or bump on the skin that may be pink-to-red, white, or flesh-colored. It can also appear as an open sore that does not heal. If left untreated, SCC can grow into surrounding tissue and spread to other parts of the body, so it is important to have it diagnosed and treated by a dermatologist as soon as possible.

Treatment for SCC depends on the size, location, and depth of the cancer, but typically includes surgical excision or Mohs micrographic surgery. For early forms of SCC called squamous cell carcinoma in-situ, treatment by cryotherapy (freezing) or topical chemotherapy may be an option. In more extensive cases, radiation therapy or systemic chemotherapy may be necessary. It is important to protect your skin from the sun and avoid other sources of UV radiation, as well as to perform regular self-examinations and see a dermatologist for regular skin exams to help detect and prevent skin cancer.