A skin biopsy is a process in which a part of the skin tissue is peeled off, processed and then studied under the microscope. When there is a skin lesion, some sample tissue is removed from that region of the skin to get it tested for any potential abnormality. A number of methods can be employed for the same depending on the loaction and the size of the lesion. The sample tissue is then put in a formaldehyde solution or a sterile vessel if it is suspected to be infected. The tissue gets processed in this way and is then examined under the microscope.
When a part of the skin unusually changes colour, size, shape or appearance in general or does not heal even long after any injury, a skin biopsy should ideally be performed. The procedure is primarily performed to diagnose skin cancer. A skin lesion biopsy can also diagnose any skin disease like psoriasis and a fungal or bacterial infection. If you see something abnormal on your skin along the lines of a skin lesion, you should not ignore it and get it checked as fast as possible to identify skin cancer that can result in early treatment.
The area of the skin from where the sample tissue would be collected is wipes with little alcohol. Sometimes, a marker is also used to mark the particular area. The method employed to obtain the skin sample depends on the location and the size of the lesion. There are three primary methods by which a skin biopsy may be performed- shave biopsy, punch biosy and excision.
Shave Biopsy: In this procedure, the tissue sample is removed when that portion of the skin is under local anaesthesia. Then the sample tissue is shaved off using a scalpel. No stitches are required to heal the area. In the case of any bleeding, some chemical is applied to control it. A sterile surgical drape is then used to keep the biopsy site covered.
Punch Biopsy: In this process too, the sample tissue is removed under local anaesthesia. A small and sharp tool, called punch, resembling a cookie cutter, is positioned on the skin lesion, forced down and then mildly rotated to get a circular patch of skin. The sample skin is detached from the tissue with a needle or a forceps. A few stitches may be required if a large skin sample has been removed and pressure is applied to stop bleeding. A sterile dressing or bandage is used to cover the biopsy site.
Excision: Again, the procedure is performed under local anaesthesia. Here a scalpel is used to remove the whole lesion. Skin grafting is required for large excisions and the biopsy site is then covered with a sterile dressing.
A person should get a skin biopsy done as soon as he discovers a lesion or an area of the skin that has abnormally changed appearance without any apparent reason. A skin lesion biopsy can detect a skin condition like psoriasis and something as dangerous as skin cancer. If skin cancer is detected early, then it can be treated on priority and get completely cured in certain cases.
Any person with an atypical skin lesion is eligible for a skin biopsy. However, there are some factors about which the doctor should know before the procedure is performed. If a person is taking any anti-inflammatory medicine or corticosteroids, the doctor should know about that as in such cases the results of the biopsy may be inaccurate. As skin biopsy involves cutting into the skin, the patient hould also inform the doctor about any bleeding problem or if he is taking any blood-diluting medication like aspirin or warfarin. And the patient must inform the doctor if she is pregnant.
Even though it's very unlikely, the patient may be susceptible to infection at the biopsy site and also a very little risk of continuous bleeding. The patient can form a scar at the biopsy site.
The patient has to take good care of the biopsy site until it completely heals and keep it dry and clean. Stitches are taken out a few days after the surgery and the sterile dressing or bandage remains in place for about two weeks till it falls off on its own. Patients often develop a fever right after a skin biopsy and there might be swelling, redness and some pain at the biopsy site as well. While it is normal for the biopsy site to bleed for some time, the patient must contact the doctor immediately in case of excessive bleeding.
The biopsy site heals completely after 2-3 weeks if the patient follows the post-treatment guidelines strictly.
The cost of the procedure can vary. However, the average price in India ranges between Rs.600 and Rs.2600.
A skin lesion biopsy can result in scarring at the biopsy site and its permanence varies from person to person.