Skin Biopsy: Types, Pain, Results, and Everything You Need to Know

What Is a Skin Biopsy?

A skin biopsy is a medical procedure in which a small sample of skin tissue is removed and examined under a microscope by a pathologist. It is the definitive method for diagnosing skin conditions, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and other skin diseases.

While a dermatologist can often develop a strong clinical suspicion about a lesion based on its appearance and dermoscopic features, a biopsy provides the microscopic confirmation needed to establish a definitive diagnosis. This confirmation is essential because treatment decisions, including whether Mohs surgery, standard excision, or another approach is most appropriate, depend on knowing the exact diagnosis and histological characteristics of the lesion.

If your dermatologist has recommended a skin biopsy, understanding the procedure can help alleviate anxiety and prepare you for what to expect.

The Three Main Types of Skin Biopsy

There are three primary biopsy techniques, each suited to different clinical situations. Your dermatologist will choose the most appropriate method based on the size, location, and suspected nature of the lesion.

1. Shave Biopsy

A shave biopsy is the most commonly performed type of skin biopsy. It involves using a thin, sharp blade to shave off the top layers of the lesion, collecting a disc-shaped sample of tissue.

How it is done: After cleaning the area and injecting local anesthesia, the dermatologist uses a specialized blade or a flexible razor blade to slice the lesion horizontally, removing a thin layer of tissue. The depth of the shave can be adjusted depending on the suspected diagnosis: a superficial shave for surface-level concerns or a deeper saucerization for lesions that may extend further into the skin.

Healing: The wound from a shave biopsy is typically shallow and heals by secondary intention (from the bottom up), similar to a scrape or abrasion. Most shave biopsy sites heal within one to three weeks, leaving a flat or slightly indented scar.

2. Punch Biopsy

A punch biopsy uses a circular cutting tool (called a punch) to remove a cylindrical core of tissue that extends through the full thickness of the skin, including the epidermis, dermis, and sometimes subcutaneous fat.

How it is done: After local anesthesia is administered, the dermatologist places the punch tool over the lesion and rotates it with downward pressure to cut a cylindrical sample. Punch tools come in various diameters, typically ranging from 2mm to 8mm, with 3-4mm being the most commonly used sizes. The sample is then gently lifted and cut free at its base.

Healing: Small punch biopsy sites (3mm or less) may be left to heal by secondary intention or closed with a single suture. Larger punch sites are typically closed with one to two sutures. Healing time is generally one to two weeks, with sutures removed at approximately seven to fourteen days depending on the location.

3. Excisional Biopsy

An excisional biopsy removes the entire lesion along with a margin of surrounding normal skin. This technique serves as both a diagnostic and therapeutic procedure. It provides a tissue sample for diagnosis while also removing the entire visible lesion.

How it is done: The dermatologist marks an elliptical (football-shaped) outline around the lesion, including a small margin of normal-appearing skin. After administering local anesthesia, the tissue is excised to the appropriate depth (usually into the subcutaneous fat) and sent to pathology. The wound is closed with layered sutures.

Healing: Excisional biopsy wounds are closed with sutures and typically heal within two to three weeks. Suture removal timing varies by location: approximately five to seven days for facial sites and ten to fourteen days for trunk and extremity sites.

What Does a Skin Biopsy Feel Like?

One of the most common concerns patients have about skin biopsies is pain. The reality is that modern biopsy techniques, combined with effective local anesthesia, make the procedure very well tolerated.

The Anesthesia Before any biopsy is performed, the area is numbed with a local anesthetic, typically lidocaine. The injection itself produces a brief stinging or burning sensation that lasts only a few seconds. Many dermatologists use techniques to minimize this discomfort, including using the smallest possible needle, injecting slowly, and warming or buffering the anesthetic solution.

During the Procedure Once the anesthesia takes effect (usually within one to two minutes), you should feel pressure but no pain during the biopsy. The tissue removal itself typically takes less than a minute. If you feel any sharpness or discomfort, inform your dermatologist immediately, and additional anesthetic can be administered.

After the Procedure Mild soreness at the biopsy site is common for one to two days after the anesthesia wears off. This discomfort is typically well managed with over-the-counter pain relievers such as acetaminophen. Most patients describe the post-biopsy discomfort as minor and comparable to a small cut.

Healing Time and Wound Care

Proper wound care promotes optimal healing and minimizes the risk of complications.

General Wound Care Instructions - Keep the biopsy site clean and covered with a bandage for the first 24-48 hours. - After the initial period, gently clean the area daily with mild soap and water. - Apply a thin layer of petroleum jelly or prescribed ointment to keep the wound moist. - Cover with a clean bandage until the wound has fully healed. - Avoid submerging the wound in water (pools, bathtubs) until healing is complete. - Avoid strenuous activity that could stretch or stress the biopsy site for the first few days.

Expected Healing Times - **Shave biopsy**: 1-3 weeks - **Punch biopsy**: 1-2 weeks (suture removal at 7-14 days) - **Excisional biopsy**: 2-3 weeks (suture removal at 5-14 days depending on location)

When Do Results Come Back?

After the biopsy is performed, the tissue sample is sent to a dermatopathology laboratory where it is processed, stained, and examined under a microscope by a specialized pathologist. This process typically takes one to two weeks.

The processing involves several steps: the tissue is fixed in formalin, embedded in paraffin wax, cut into extremely thin sections (a few microns thick), mounted on glass slides, and stained with special dyes that highlight different cellular structures. The dermatopathologist then examines these slides and generates a detailed report.

Your dermatologist will contact you with the results once the pathology report is received. At our clinic, we understand that waiting for biopsy results can be an anxious time, and we make every effort to communicate results promptly.

Understanding Your Results

Biopsy results typically fall into one of several categories:

Benign The lesion shows no evidence of cancer or precancerous change. Depending on the specific diagnosis, no further treatment may be necessary, or conservative management may be recommended.

Precancerous (Actinic Keratosis or Bowen's Disease) The lesion shows abnormal cellular changes that could progress to skin cancer if untreated. Treatment options for precancerous lesions include cryotherapy, topical medications, photodynamic therapy, or in some cases, surgical removal.

Basal Cell Carcinoma The biopsy confirms BCC and identifies the specific subtype (nodular, superficial, morpheaform, infiltrative, etc.). The subtype, along with the tumor's location and size, guides the choice of treatment. For many BCCs, Mohs micrographic surgery offers the highest cure rate at 99%.

Squamous Cell Carcinoma The biopsy confirms SCC and provides information about differentiation (well, moderate, or poor), depth of invasion, and the presence or absence of high-risk features such as perineural invasion. This information is essential for determining whether Mohs surgery (97% cure rate), standard excision, or additional treatment is needed.

The On-Site Biopsy Advantage

Having your biopsy performed at the same facility where your treatment will take place offers important advantages. At our clinic at Assuta and Herzliya Medical Center, Dr. Yehonatan Kaplan performs biopsies on-site, ensuring seamless continuity of care from initial evaluation through diagnosis and definitive treatment.

This integrated approach means that if your biopsy confirms skin cancer, your treatment can be planned and scheduled without delays or the need to transfer medical records between different providers. For patients who require Mohs surgery, having the same physician who performed the biopsy also perform the definitive surgery ensures the most informed and individualized care.

If your dermatologist has recommended a skin biopsy, know that you are taking an important step toward protecting your health. The procedure is brief, well-tolerated, and provides the information needed to guide the most effective treatment plan. Do not let apprehension about the biopsy delay your evaluation. Early diagnosis remains the single most important factor in achieving the best outcomes for skin cancer.