How are basal and squamous cell skin cancers found?
Basal and squamous skin cancers can be found early. As part of a routine check-up, your doctor should look at your skin carefully. Many doctors advise that you also check your own skin once a month. This is best done in front of a full-length mirror. A hand-held mirror can be used for places that are hard to see. You should know the pattern of moles, freckles, and other marks on your skin so that you’ll notice any changes. Be sure to show your doctor any area that concerns you and ask your doctor to look at areas that may be hard for you to see.
Friends and family members can also help you with these exams, especially for those hard-to-see areas, such as your scalp and back. For a more details about skin self-exam, see our document called Skin Cancer: Prevention and Early Detection and the booklet Why You Should Know About Melanoma.)
Most skin cancers are brought to a doctor’s notice because of signs or symptoms a person is having. Any sore, lump, blemish, marking, or change in the way an area of the skin looks or feels may be a sign of skin cancer or a warning that cancer might occur. The skin might become scaly or crusty or begin oozing or bleeding. It may feel itchy, tender, or painful. It might be red or swollen.
Friends and family members can also help by telling one another about abnormal-looking areas of skin. The key warning signs are:
- A new growth
- A spot or bump that’s getting bigger
- A sore that doesn’t heal within a couple of months
If you or your doctor finds something that doesn’t look normal, certain tests may be used to find out if it is cancer or something else. If it is skin cancer, more tests may be done to find out if it has spread to other places.
Signs and symptoms of basal and squamous cell skin cancer
Skin cancers often don’t cause symptoms until they become quite large. Then they can bleed or even hurt. But they can often be seen or felt long before they reach this point.
Basal cell carcinomas usually start on places exposed to the sun, especially the head and neck, but they can occur anywhere on the body. They often show up as flat, firm, pale areas or as small, raised, pink or red, shiny, pearly areas that may bleed after minor injury. You might see one or more abnormal blood vessels, a lower area in the center, or blue, brown, or black areas. Large ones may have oozing or crusted spots.
Squamous cell cancers may show up as growing lumps, often with a rough, scaly, or crusted surface. They may also look like flat, reddish patches that grow slowly. They tend to appear on sun-exposed places of the body such as the face, ear, neck, lip, and back of the hands. Less often, they form in the skin of the genital area. They can also develop in scars or skin sores elsewhere.
Both of these types of skin cancer may develop as a flat area showing only slight changes from normal skin.
If your doctor has any reason to suspect skin cancer, one or more tests or exams below might be done.
History and physical exam
Your doctor will ask you when the mark on your skin first appeared, whether it has changed in size or the way it looks, and if it has caused any symptoms (pain, itching, bleeding, etc.). You may also be asked about past exposures to causes of skin cancer (including sunburns and tanning) and if you or anyone in your family has had skin cancer.
During the exam, the doctor will note the size, shape, color, and texture of the area in question, and whether there is bleeding or scaling. He or she may check the rest of your body for spots and moles that could be related to cancer. The doctor may also check nearby lymph nodes (bean-shaped collections of immune system cells) to feel if they are larger or firmer than usual. This could mean the cancer has spread to the nodes.
If you see your regular doctor, you may be referred to a doctor called a dermatologist. This doctor has special training in skin diseases and will look at the area more closely. He or she may use a special magnifying lens (a dermatoscope) to see spots on the skin. Sometimes a thin layer of oil is used with this test. Pictures of the spot may be taken.
If the doctor thinks that an area might be skin cancer, a sample of skin will be taken to be looked at under a microscope. This is called a skin biopsy. There are different ways to do a biopsy. The choice depends on the most likely type of skin cancer, where it is on the body, and the size of the area. Any biopsy is likely to leave at least a small scar. Different biopsy methods leave different scars. Ask your doctor ahead of time about the type of biopsy you will have and what kind of scar it will leave.
No matter which type of biopsy is done, it should remove as much of the area in question as can be done so that a precise diagnosis can be made. If the biopsy removes the whole tumor, it is often enough to cure the skin cancer without further treatment.
Skin biopsies are done using numbing medicine, which is put into the area with a very small needle.
Types of skin biopsies
Shave biopsy: To do this biopsy, the doctor numbs the skin and then “shaves” off the top layers of the skin with a surgical blade.
Punch biopsy: This method is used to remove a deeper sample of skin. The doctor uses a tool that looks like a tiny round cookie cutter. After skin is numbed, the doctor uses the tool to cut through all layers of the skin to remove the tissue sample. The edges of the biopsy site are then stitched together.
Incisional and excisional biopsies: These types of biopsies are used if the doctor needs to look at deeper layers of the skin. The skin is numbed, and a scalpel is used to cut through the full thickness of the skin. A wedge of skin is removed and the edges are sewn back together. Incisional biopsy involves removing only part of the tumor. If the whole tumor is removed, it is called an excisional biopsy.
All skin biopsy samples are sent to a lab, where they are looked at under a microscope by a pathologist (a doctor trained in looking at tissue samples to diagnose disease).
Lymph node biopsy
In rare cases when basal or squamous cell skin cancer spreads, it can go first to nearby lymph nodes, which are small, bean-shaped collections of immune cells. If the doctor feels the lymph nodes are too large or too firm a lymph node biopsy may be needed. This is done to find out whether the cancer has spread from the skin to nearby lymph nodes.
There are 2 ways to do a lymph node biopsy. In fine needle aspiration (FNA), a thin, hollow needle is used to remove very small pieces of tissue from a lymph node. This does not leave a scar. If the doctor suspects there is cancer in a lymph node that the FNA did not find, a surgical lymph node biopsy may be done. For this, the doctor removes the whole lymph node, leaving a small scar.
Last Medical Review: 09/18/2012
Last Revised: 01/17/2013