Needle biopsy is a simple procedure used in diagnosis of a breast lump. It involves removing a small portion of the breast tissue from the lump and examining it under the microscope. The lumps detected during a breast exam, mammogram or sonogram is usually checked put through a biopsy.
Usually the mammogram or the sonogram gives a good result as regards to the nature of a breast lump. But if the picture is still unclear, then a biopsy is carried out. The biopsy is done either with a needle or through open surgery. The biopsy usually gives a correct picture about the lump.
Types of Needle Biopsy
There are mainly three types of needle biopsy, namely fine- needle aspiration biopsy, large core needle biopsy and directional vacuum assisted core biopsy. In fine needle aspiration biopsy a thin needle is inserted into the lump to draw out a small sample of cells or fluid. This is the cheapest procedure and least invasive. But it requires a pathologist especially trained in cyto pathology.
In large core needle biopsy a wider needle is used. Multiple samples of tissues can be removed with this. The samples are usually the size of a grain of rice. In vacuum assisted needle biopsy, a probe with a vacuum device is used. A wider needle removes more tissues within short period of time. It requires only a single needle insertion.
Selection of Needle Biopsy
The type of needle biopsy used to assess a particular breast abnormality, depends on several factors. The nature of the breast abnormality is an important factor to be considered while selecting the type of needle biopsy. This is usually decided by the radiologist. It also depends on the skills of the pathologist.
Fine needle biopsy requires a pathologist trained in cytopathology. Fine needle biopsy is cheaper. Vacuum directed core biopsy requires special equipments and can only be done in such laboratories. It is more expensive too. Wider needles provide better and more accurate results than the fine one. But the wider needles leave a mark on the skin.
How is it Done?
A fine needle biopsy usually takes 5 to 15 minutes to complete. The patient lies on the examination table, uncovered from waist up or a gown may be draped. An injection to numb the area where biopsy is to be done is given. Then the fine needle is inserted,sometimes with the guidance of ultrasound. The fluid or the tissue to be examined is taken out. Pressure is applied to the part after the needle is remove and a bandage is put on.
The preparation of the patient for the procedure is same as above. A numb sot is given here too. A small cut is made at the site and the wider needle with a special tip is inserted. 3 to 12 tissue samples are usually taken. The needle is removed followed by pressure to the area and bandage. This also usually takes 15 minutes.
A vacuum assisted biopsy is usually done by a radiologist or a surgeon. After the patient is prepared and made to lie down, a numb shot is given. Then a small incision is made through which the vacuum probe is inserted. The probe collects samples by probing. Can collect a number of samples without removing the probe.
The biopsies can be done in a sitting or lying down position The hands are placed at the sides or above the head according to the site and necessity of the abnormality.
Some of the dangers of biopsy include infection at the biopsy site, bleeding, collection of inadequate tissue samples, dizziness and fainting.
Needle Biopsy versus Surgery
A needle biopsy is done using a needle. So comparatively lesser samples are obtained. There is a chance that the lump itself may be missed out. But it is less expensive and leaves very little scar. In surgery, the samples are obtained after opening up the area. But a better view and better samples may be obtained. The lump itself may also be removed during the procedure. But surgical procedure itself leaves some scar which can interfere with reading the mammograms later on.
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