Brief Answer:
Please find differences between FNAC and core biopsy discussed below

Detailed Answer:
Hi XXXXXXX
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

I have done hundreds of image guided FNAC and biopsy procedures and if there is any thing specific you want to discuss then please let me know.

1. FNAC (Fine needle aspiration cytology)
(i) This is a method to arrive at a diagnosis by sucking few cells from a problem area and studying it under a microscope. It causes mild pain like injection.
(ii) A negative pressure is created with the help of suction created usually by placing a syringe in a piston mechanism and a thin bore needle is used to aspirate cells.
(iii) The cells are few in number and are immediately spread over a glass slide and then fixed with chemicals.
(iv) The slides are then examined to look for abnormal cells under a microscope.
(v) This is a safe method with less complications due to procedure.
(vi) If the cells are insufficient then it has to be repeated.

2. Core biopsy
(i) This is a method by which a large bore needle is used usually under imaging guidance and with a sudden release mechanism, tissue from part of the core of problem area is cut with a needle called tru cut biopsy needle. Usually local anesthesia is given to reduce pain.
(ii) The tissue is sampled at more than one area if required and the columns of tissue obtained are taken in a formalin bottle.
(iii) The tissues are then processed and made in to blocks and slides are made from the blocks.
(iv) Material studies is larger than in FNAC and even special staining can be done.
(v) There is a small risk of complication due to bleeding and this depends on the area of biopsy.
(vi) Core biopsy usually gives a confirmed diagnosis because many cells are studied from the disease area and less likely to be repeated.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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