Skin Cancer Testing: Hospital Procedures Explained

Skin cancer is a common disease in which malignant cells form in the tissues of the skin. It can appear in many shapes and sizes and can occur anywhere on the body, although it is often found on areas that receive more sun exposure, such as the face, head, neck, and arms. The detection and diagnosis of skin cancer typically involve a combination of self-examinations, clinical screenings, and specialized tests. While self-examinations and screenings help identify suspicious areas, tests such as biopsies and imaging scans confirm the presence of cancer and determine its extent. This paragraph provides an introduction to the topic of how hospitals test for skin cancer, setting the context by briefly describing skin cancer and outlining the overall process of detection, diagnosis, and testing.

Self-examination

• Timing: Choose a time when you're fresh out of the bath or shower, as your skin will be clean and relaxed, making it easier to examine.
• Lighting and Tools: Ensure you have adequate lighting and, if needed, use a hand mirror to get a clear view of hard-to-see areas. You can also use a blow dryer to expose sections of your scalp for inspection.
• Involve a Partner: Consider enlisting the help of a spouse, partner, or close friend to assist with examining areas like your back, scalp, and other hard-to-reach spots.
• Know Your Skin: Familiarize yourself with the pattern of moles, blemishes, freckles, and other marks on your skin. This knowledge will help you notice any changes during future self-examinations.
• Examine Your Body: Start with your face, ears, neck, chest, and belly. Women should lift their breasts to check the skin underneath. Move on to the underarm areas, both sides of the arms, the tops and palms of the hands, between the fingers, and under the fingernails.
• Check Your Lower Body: Inspect the front of your thighs, shins, tops of your feet, between your toes, and under your toenails.
• Don't Forget the Genitals: Sit down and prop each leg on a stool or chair to examine your genital area using a hand mirror.
• Look for Changes: Keep an eye out for any new, expanding, or changing growths, spots, or bumps on the skin. This includes sores that don't heal, rough or scaly patches, and areas that crust or bleed.
• Understand Your Risk Factors: Consider your history of sun exposure, sunburns, and the use of tanning devices. If you or anyone in your family has had skin cancer, it's important to factor that into your self-examination routine.
• Document and Report Concerns: If you notice anything concerning, take close-up photos of the area regularly to track changes. Show these photos to your doctor, who can advise on whether further evaluation is needed.

Remember, self-examination is not a substitute for professional medical advice. If you notice any unusual changes or have concerns, consult a dermatologist or your primary care physician for a comprehensive skin cancer screening.

Physical examination

If a patient notices anything unusual during a self-exam, they should have it checked by a doctor. The doctor will then examine the patient's skin and may refer them to a dermatologist who can perform more specialised tests and diagnose skin cancer. A dermatologist may use a dermatoscope (a special magnifying lens and light source) to examine the skin more closely. This process is called dermoscopy or dermatoscopy. A thin layer of alcohol or oil may be used with the dermatoscope, and the doctor may take a digital photo of the spot.

If skin cancer is suspected, the patient may undergo a skin biopsy, which is the main test to diagnose skin cancer. A small sample of skin is removed and examined under a microscope to look for cancer cells. There are several types of skin biopsies, including excisional, shave, and punch biopsies. The type of biopsy performed depends on the suspected type of skin cancer, its location, and the size of the affected area, among other factors.

It is important to note that skin cancer screening and self-examinations may have risks and may not always be helpful. Some cancers never cause symptoms or become life-threatening, but their detection through screening may lead to treatment with serious side effects. Additionally, screening test results may be false positives or false negatives, which can cause unnecessary anxiety or delay medical care.

Biopsy

A skin biopsy is a procedure that removes a small sample of skin for further testing. It is often used to diagnose skin cancer, which is the most common type of cancer in the United States. Skin biopsies can also help diagnose other skin conditions such as psoriasis, eczema, actinic keratosis, and warts, as well as bacterial or fungal infections.

There are several types of skin biopsies, and the doctor will choose the most suitable option based on the suspected type of skin cancer, its location, size, and other factors. Before the procedure, the provider will clean the site and administer a local anesthetic to numb the area.

One type of skin biopsy is a shave biopsy, where a doctor uses a small surgical blade or scalpel to remove the top layers of the skin. An ointment, chemical, or small electrical current is then applied to stop the bleeding. Shave biopsies are often used when basal cell or squamous cell skin cancer is suspected, or when a rash appears to affect only the top layer of the skin.

Another type is a punch biopsy, where a tool with a round blade is used to remove a deeper sample of the skin. The punch biopsy tool is rotated on the skin until it cuts through all the layers, and the sample is then lifted out. The wound is often stitched together and covered with a bandage.

An excisional biopsy is performed when melanoma, the most serious type of skin cancer, is suspected. It may also be used for basal cell and squamous cell skin cancers. This type of biopsy removes the entire tumor or lesion, and it often cures basal and squamous cell skin cancers without the need for further treatment.

An incisional biopsy is similar to an excisional biopsy, but only a portion of the tumor or lesion is removed. This type of biopsy is often used when the skin lesion is large.

Finally, an FNA (Fine Needle Aspiration) biopsy is a less invasive procedure where a thin, hollow needle is used to remove very small fragments of the lymph node. Local anesthesia is sometimes used to numb the area. FNAs may not always provide a large enough sample, so further surgery may be required if cancer is suspected.

Imaging tests

One example of an imaging test is a CT scan, which can be used to help guide a biopsy needle into place for a lymph node that is deeper in the body. Ultrasound scans can also be used for this purpose.

Another imaging test is a PET scan, which involves injecting a tracer (a radioactive sugar) into a vein. Cancer cells use more sugar than normal cells, so the tracer shows up in cancer cells. This can help to show if skin cancer has spread to the lymph nodes or other areas of the body.

A technique called RCM (reflectance confocal microscopy) uses a laser and a special microscope to create a detailed, three-dimensional image of the skin. This can help doctors determine if a biopsy is needed and can be useful for people with many unusual moles.

Lymph node examination

Lymph nodes are bean-shaped structures that are part of the lymphatic system, which is a network of thin tubes and nodes that carry a clear fluid called lymph around the body. Lymph nodes play a crucial role in fighting infections and destroying old or abnormal cells. They filter lymph fluid and trap bacteria, viruses, and cancer cells.

During a physical examination for skin cancer, a doctor will typically feel the lymph nodes near the skin to check for any abnormalities. If the lymph nodes feel too large or firm, it could indicate that cancer has spread to them. In such cases, the doctor may recommend a lymph node biopsy to confirm the presence of cancer.

A lymph node biopsy, also known as an excision biopsy, is a procedure where a small sample of lymph node tissue is removed for examination. This can be done through a fine-needle aspiration (FNA), where a thin, hollow needle is used to extract a small fragment of the lymph node. FNA is a relatively non-invasive procedure that usually does not cause significant discomfort or leave scars. However, it may not always provide a large enough sample to detect cancer cells.

If the FNA results are inconclusive, or if the doctor still suspects the presence of cancer, a more invasive procedure may be necessary. This involves making a small incision above the swollen lymph node and removing it for laboratory testing. Local or general anaesthesia may be used to numb the area before the biopsy. The removed lymph node is then examined under a microscope by a pathologist to determine the presence of cancer cells.

Lymph node biopsies are crucial in determining the stage of cancer and developing an appropriate treatment plan. If cancer is detected in the sentinel lymph node, it suggests that cancer may have spread to other nearby lymph nodes or organs. This information helps doctors assess the extent of the disease within the body and make informed decisions about the patient's care.

Frequently asked questions