Medically reviewed by Prof. Dr. Aamer Nadeem Chaudhary, M.B.B.S., D.M.R.D., F.C.P.S. (Diagnostic Radiology), Consultant, Al-Nasar Lab & Diagnostic Centre. Updated October 2026.
Quick answer: A breast biopsy takes a small sample of tissue so it can be examined under a microscope. Core needle biopsy is the preferred method because it removes a thin cylinder of tissue, which allows a complete diagnosis. FNAC uses a finer needle and collects cells only. It is done under local anaesthetic, takes around twenty minutes, and most results come back benign.
Book an image guided biopsy: call 0300 0341944. Performed at our main Johar Town campus.
FNAC or core needle biopsy?
| FNAC | Core needle biopsy | |
|---|---|---|
| What it takes | Loose cells through a fine needle | A thin cylinder of intact tissue |
| Needle size | Very fine, similar to a blood test | Thicker, needs local anaesthetic |
| Anaesthetic | Often none needed | Local anaesthetic |
| What it can answer | Whether cells look abnormal | Full diagnosis, including whether a cancer is invasive |
| Hormone receptor testing | Generally not possible | Yes, which is why it is preferred |
| Best used for | Draining a cyst, sampling a lymph node | Any solid lump needing a diagnosis |
| Report time | Usually faster | Typically a few working days |
Why core needle biopsy is preferred
The difference matters more than it first appears, and it comes down to architecture.
FNAC collects individual cells floating free. A pathologist can say whether those cells look abnormal, but cannot see how they are arranged in the tissue.
That arrangement is what distinguishes ductal carcinoma in situ, where abnormal cells remain confined inside the duct, from invasive cancer, where they have broken through the duct wall. Those two have very different treatments and very different outlooks, and only intact tissue shows the difference.
A core sample also provides enough material for hormone receptor and HER2 testing, which determines which treatments will work. Those results shape the entire treatment plan, and they usually cannot be obtained from FNAC.
FNAC still has a clear role: draining a cyst that is causing discomfort, and sampling an enlarged lymph node in the armpit.
What does image guided mean?
The needle is positioned using live imaging rather than by feel, so the sample comes from exactly the right spot.
- Ultrasound guided is the most common. The radiologist watches the needle on screen in real time as it enters the lesion. Quick, comfortable, no radiation
- Stereotactic, or mammogram guided, is used for microcalcifications that are visible only on a mammogram and cannot be seen on ultrasound
- MRI guided is reserved for lesions seen only on breast MRI
Guidance matters. Biopsying by feel alone risks missing a small lesion and getting a falsely reassuring result.
What happens on the day?
- You lie on a couch and the area is scanned to locate the lesion precisely
- The skin is cleaned and local anaesthetic is injected. This stings briefly, like a dental injection, and is the only genuinely uncomfortable part
- A tiny nick is made in the skin
- The needle is guided in under imaging. For a core biopsy the device makes a loud click as it takes each sample. This surprises people, so expect it. It is the sound of the mechanism, not of anything going wrong
- Usually three to six samples are taken to make sure the diagnosis is reliable
- Sometimes a tiny titanium marker clip is placed to mark the site for future imaging. It is harmless, permanent and does not set off airport detectors or prevent an MRI
- Firm pressure is applied, then a dressing. No stitches are needed
The whole appointment is usually twenty to thirty minutes. You go home the same day.
Afterwards
- Bruising is normal and can look dramatic over the following days. It settles
- Mild soreness for a day or two. Paracetamol is usually enough. Avoid aspirin and similar painkillers unless your doctor advises otherwise, as they increase bruising
- Keep the dressing dry for about 24 hours
- Wear a well supporting bra, including at night for the first night, as it reduces discomfort considerably
- Avoid heavy lifting and strenuous exercise for a couple of days
- Contact the centre if you develop increasing pain, spreading redness, fever or bleeding that does not stop with pressure
How to prepare
- Tell the team about blood thinners. Warfarin, clopidogrel, aspirin and similar medicines may need adjusting beforehand. Never stop them yourself, ask the doctor who prescribed them
- Mention any bleeding disorder or previous problems with bleeding
- Tell them if you are pregnant or breastfeeding
- Bring your previous mammogram, ultrasound and reports. The radiologist needs to see the target
- Wear a two piece outfit and bring a supportive bra
- No fasting is needed and you can eat normally
- Arrange for someone to accompany you if you would prefer not to be alone
Understanding the report
Reports are often graded from B1 to B5, or described in words. Broadly:
- Benign: no cancer. Fibroadenoma, cyst, fibrocystic change and fat necrosis all fall here. This is the most common outcome
- Uncertain or atypical: changes that are not clearly benign or malignant. Usually leads to a larger sample or surgical removal to be certain
- Suspicious: features that point towards cancer but are not conclusive
- Malignant: cancer confirmed. The report will usually also state the type, the grade, and whether it is in situ or invasive
If cancer is confirmed, further details follow: oestrogen and progesterone receptor status, and HER2 status. These are not academic. A hormone receptor positive cancer can be treated with hormone therapy, and a HER2 positive cancer responds to specific targeted drugs. This is why a core biopsy is worth the extra needle.
There is one important caveat. If the biopsy result does not fit what the imaging and examination suggested, your team may repeat it or proceed to surgical biopsy. That is not an error, it is a safety check built into the process.
Breast biopsy at Al-Nasar Lab
Al-Nasar Lab & Diagnostic Centre has served Lahore since 1996 and holds ISO 15189:2022 accreditation from the Pakistan National Accreditation Council. Ultrasound guided biopsy, FNAC, mammography and ultrasound are available at our Johar Town campus, with laboratory processing on the same site.
Related reading: breast cancer screening and ultrasound compared with mammography.
See our accreditations, find your nearest location, or contact us to book.
Frequently Asked Questions
Is a breast biopsy painful?
The local anaesthetic injection stings for a few seconds. After that you feel pressure rather than pain. Mild soreness and bruising for a day or two is normal.
How long do breast biopsy results take?
Typically a few working days for a core needle biopsy. FNAC results are often faster.
Does a biopsy mean I have cancer?
No. A biopsy is how a definite answer is obtained, and the majority of breast biopsies come back benign.
What is the difference between FNAC and core biopsy?
FNAC collects loose cells, core biopsy removes intact tissue. Only core tissue shows whether a cancer is invasive and allows hormone receptor and HER2 testing.
Can a biopsy spread cancer?
This is a common fear and it is not supported by evidence. Image guided needle biopsy is the standard worldwide precisely because it is safe and accurate.
This article is for general information and is not a substitute for medical advice. Please discuss your results with the doctor managing your care.
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