Fine needle aspiration (aka "FNA") utilizes a smaller needle to aspirate cells (as opposed to a core of tissue) from the tumor.   This is processed for cytology (as opposed to pathology in the case of core biopsy) to determine sarcoma subtype and sometimes grade.   The sample aspirated with this technique consists of scattered cells that do not usually maintain the typical "architecture" of the tumor.   This makes establishing a diagnosis more challenging.  Despite these challenges, FNA is a safe and reasonably accurate biopsy technique in experienced hands.

Fine needle biopsies have advantages to surgery in that they can be done quickly, with only sedation and local anesthetic.  If they are positive for malignancy, they are useful, but a negative result is not reliable because it is possible to miss the malignant sector of a nonhomogeneous tumor.  In about 20% of cases it is not possible to make a diagnosis from the material. [2, 3, 5, 13]

<b>The problems with fine needle biopsies:

1. they may not give enough tissue for a diagnosis 

2. they may miss the cancerous part of the tumor

3. they may loosen cancer cells to float through the bloodstream and set up secondary tumors at other sites  [distant metastases]

4. they may loosen cancer cells to float through the lymph system and set up  secondary tumors at other sites  [lymphatic metastases]

5. they may drag cancer cells with them along the tract of their path and set up secondary tumors at other sites [tract or track implantation]

6. the tumor is still there </b>


   Insertion of a needle into an LMS tumor might liberate LMS cells into the lymphatic or blood circulation, or possibly seed cells along the needle track.   For this reason, I personally feel that biopsies should be kept to a minimum, and used only when situations are inoperable, and a diagnosis is imperative.  If lesions are operable, an excisional biopsy with wide margins would remove the suspicious lesion, treat it, give a diagnosis, and also provide tissue for chemoresistance and other testing.  Fine needle biopsies can miss the malignant part of the lesion, can remove too little tissue for adequate diagnosis, and do not remove enough tissue for chemosensitivity testing.]  Most importantly, to accurately diagnose and classify most sarcomas, an expert cytopathologist to examine the specimen is paramount.

Needle biopsies should be taken seriously as they can indeed cause seeding along the path of the needle.  The best course of action would be to surgically remove the tunnel the needle had followed in the next surgery.  Fine needle aspiration may also shed breast cells into peripheral blood [28].  

<b>For rebuttal of this argument against fine needle biopsies:</b> &&url

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