Skin cancer usually presents as a growth or lump on the skin. The specific signs of these growths depend upon the type of cancer present. Symptoms pertaining to the type of cancer are listed below:-

Basal cell carcinoma

• Raised, smooth, pearly and translucent bump on the skin
• Pink or red growths with a crusted centre
• Appearance of small blood vessels on the lump or lesion

Squamous cell carcinoma

• Red scaly patches with irregular borders
• Ulceration and bleeding in these patches
• Dome-shaped growths with rough surface and an indented centre

Melanoma

• Moles that are asymmetrical and irregular
• Change in colour or diameter of the mole
• Redness, itching, ulceration, bleeding
• Spots or growths of various colours, ranging from brown to black

• A physical exam by a dermatologist would help in determining whether a lump is cancerous or not. The dermatologist would take into account the specifics of the lump such as the size, colour, shape etc.
• Biopsy- a biopsy would be required to confirm whether the lump is cancerous and if yes, then which type of cancer it is.
• If the cancer is a basal cell cancer, a biopsy alone can determine the extent of the cancer, as it does not spread in most cases.
• If the cancer is found to be squamous cell cancer or a melanoma, further tests may be needed to determine the extent of the cancer, as they are capable of metastasizing.
• Imaging tests may be required to determine the presence of cancer in neighboring cells and lymph nodes.

 A number of surgical techniques can be used depending upon the type of cancer and its extent.

• Curettage and electrodessication- in this procedure, the skin is repeatedly scraped with a long sharp instrument called a curette and the skin is then cauterized with an electric needle (electrode).
• Surgical excision- a surgical knife is used to cut out the tumor along with some tissue. It is then diagnosed to make sure that the entire tumor has been removed.
• Mohs surgery- is a microscopically controlled surgery wherein the tumor is removed with a small piece of tissue which is then examined under a microscope for cancer cells. If cancer cells are present, some more tissue is removed and examined, and this is continued until no more cancer cells are found.
• Radiation Therapy
• Chemotherapy
• Photodynamic therapy
• Biological Therapy
• Cryosurgery

• Pain
• Swelling
• Bleeding
• Infection
• Nerve damage
• Numbness
• Fatigue
• Scarring 
• Lymphedema
• Risk of cancer recurrence
• Metastasis ( cancer spreading to different body parts )

Regular skin examinations by the patient themselves and the doctor at regular intervals would be necessary. A few tests may also be recommended by the doctor to make sure the cancer does not regrow.