A biopsy is the removal of a small sample of tissue or cells so a lab can examine it under a microscope, most often to check for cancer or other abnormalities. The specific way it’s done depends on where in your body the sample needs to come from, but most biopsies fall into a few main categories: needle biopsies, skin biopsies, endoscopic biopsies, and surgical biopsies. Many are outpatient procedures that take less than an hour.
Needle Biopsies
Needle biopsy is the most common approach for sampling lumps or masses inside the body. A specialized needle is inserted through the skin to reach the suspicious area, and cells or tissue are drawn out for testing. There are a few variations depending on how much tissue is needed.
Fine-needle aspiration uses a long, thin needle attached to a syringe. The doctor inserts it into the area of concern and draws out fluid and cells. This is often used for thyroid nodules, lymph nodes, and breast lumps. It’s quick and typically causes only mild discomfort, sometimes with just a local numbing agent or no anesthesia at all.
Core needle biopsy uses a slightly larger needle with a cutting tip to pull out a small cylinder of tissue. Because it captures a more intact piece, it gives the pathologist more to work with. Vacuum-assisted biopsy adds suction to collect a larger sample through the same needle, which is common in breast biopsies.
For areas that are hard to reach or can’t be felt from the surface, imaging guidance is used. The doctor watches a live ultrasound, CT scan, or MRI to steer the needle to exactly the right spot. This is sometimes called an image-guided biopsy, and it’s standard for biopsies of the liver, lung, kidney, and deep lymph nodes.
Skin Biopsies
When the concern is on or near the skin’s surface, the approach is more straightforward. A shave biopsy uses a razor-like tool to scrape off a thin layer from the top of a lesion. A punch biopsy uses a small, circular cutting tool that’s pressed and rotated into the skin to remove a deeper, plug-shaped sample. Both are done with local anesthetic and take just a few minutes.
For larger or deeper skin abnormalities, an incisional biopsy removes a wedge of tissue with a scalpel, while an excisional biopsy removes the entire suspicious area. These may require stitches. Excisional biopsies serve double duty: they collect the sample and can also be the treatment if the entire abnormality is removed with clear margins.
Endoscopic Biopsies
If the area of concern is inside a hollow organ like the stomach, colon, bladder, or lungs, a biopsy is typically done during an endoscopy. A thin, flexible tube with a camera and light on the end is threaded into the body through a natural opening (mouth, rectum, or urethra) or through a small incision. Once the doctor can see the suspicious spot on screen, tiny tools are passed through the tube to snip or scrape a tissue sample.
The most common tool is a pair of biopsy forceps, small jaws that pinch off a piece of tissue. Other options include cytology brushes that sweep cells from a surface, snares that loop around and cut away polyps, and fine needles guided by ultrasound built into the endoscope tip. You typically won’t feel the moment the sample is taken, because the lining of organs like the colon has very few pain-sensing nerves.
Surgical Biopsies
When a needle or endoscope can’t safely reach the target, or when a larger tissue sample is needed for an accurate diagnosis, a surgical biopsy is performed. A surgeon makes an incision through the skin and underlying tissue to access the suspicious area directly. This can be done to remove just a portion of the mass (incisional) or the entire thing (excisional).
Surgical biopsies of areas near the body’s surface are often done with local or regional anesthesia, meaning you’re awake but the area is numb. For masses inside the chest or abdomen, general anesthesia is used. Recovery takes longer than with needle biopsies, and you may have restrictions on physical activity for a period afterward.
Liquid Biopsies
A newer option doesn’t involve tissue removal at all. A liquid biopsy is a standard blood draw that looks for traces of cancer circulating in your bloodstream. Specifically, it detects circulating tumor cells (cancer cells that have broken off from a tumor) and fragments of tumor DNA floating in your blood. It’s not a replacement for tissue biopsy in most cases, but it’s increasingly used to monitor how a known cancer is responding to treatment or to detect genetic mutations that guide therapy choices.
What Happens Before the Procedure
Preparation depends on the type of biopsy. For a simple skin biopsy or fine-needle aspiration, you may not need to do anything special. For deeper needle biopsies and any procedure involving sedation or general anesthesia, preparation is more involved.
If you take blood thinners, your doctor will likely ask you to stop them a certain number of days beforehand to reduce bleeding risk. The exact timing depends on the medication and the type of biopsy. Diabetes medications and diuretics may also need to be adjusted or paused. If you take a GLP-1 medication (commonly prescribed for diabetes or weight loss), you may need to switch to a clear liquid diet the day before and stop all food and drinks eight hours before your arrival time, because these drugs slow stomach emptying.
For procedures with sedation, the general rule is to stop eating solid food at midnight the night before. You can usually drink clear liquids like water, black coffee, or apple juice up until two hours before your scheduled arrival. After that cutoff, nothing by mouth, including water.
Pain and Anesthesia
Most biopsies are far less painful than people expect. Skin biopsies and needle biopsies use a local anesthetic injected into the area. You’ll feel the initial sting of the numbing shot, but the biopsy itself is typically pressure rather than sharp pain. Fine-needle aspiration is sometimes done without any anesthesia at all, since the needle is so thin.
Endoscopic biopsies usually involve sedation, so you’re drowsy or lightly asleep and unlikely to remember the procedure. Surgical biopsies range from local anesthesia for surface procedures to full general anesthesia for anything inside the chest or abdomen.
How Long Results Take
After the tissue is collected, it goes to a pathology lab where it’s processed, sliced into thin sections, stained, and examined under a microscope. The College of American Pathologists recommends a turnaround time of two business days from when the lab receives the specimen to when the final report is signed. In practice, results often take two to five business days. A study of core breast biopsies at Washington University found an average turnaround of just over two and a half days. More complex cases requiring additional testing, like genetic or molecular analysis, can take one to two weeks.
Recovery and Risks
For needle and skin biopsies, recovery is straightforward. You may have mild soreness, bruising, or slight bleeding at the site. Applying ice wrapped in a thin towel can help with discomfort, and over-the-counter pain relievers are usually sufficient. If you received stitches, you’ll care for the wound until they’re removed. If not, basic wound care continues until the skin heals over.
Serious complications from biopsies are uncommon. The main risks are bleeding, bruising, and infection at the biopsy site. Signs of infection to watch for include increasing pain, swelling, redness, fever, or chills. Minor bleeding and temporary soreness are normal and typically resolve without treatment. Prostate biopsies, for instance, frequently cause minor bleeding and urinary symptoms that don’t require intervention, though up to 25% of men experience temporary urinary issues afterward. Biopsy-related mortality is rare across all types.
Recovery from surgical biopsies takes longer, potentially a few days to a couple of weeks depending on the location and extent of the incision. Your care team will give specific instructions about when you can resume exercise, lifting, bathing, and other activities based on your particular procedure.