Fine-Needle Aspiration Samples

Fine-Needle Aspiration (FNA) biopsy is a minimally invasive, cost-effective, accurate, and rapid diagnostic procedure to evaluate palpable or deep-seated masses.

Instructions for clinicians performing FNA of superficial masses:

We highly recommend that an experienced physician perform FNA of superficial masses. FNA procedure performed by an inexperienced physician often yields a sub-optimal or non-diagnostic sample prompting additional diagnostic procedures with potentially more complications. Our staff Pathologists are experienced in FNA and available to perform FNA on patients referred to the FNA clinic at UC Davis Cancer Center, as well as within the UC Davis Medical Center.

Clinicians experienced in performing FNA should follow the recommendations/procedures below.

EQUIPMENT:

We recommend 22 or 25 gauge, 1.5 inch long, disposable needles, 10 cc disposable plastic syringes with Luer-Lok tip, and a syringe holder, or a 3 cc syringe without the syringe holder. Clean glass slides with a frosted end should be used. The patient's name and medical record number should be written with a pencil on the frosted end. If more than one site is aspirated, please indicate the site/source on the frosted end of the slide. Please submit aspirations from separate sites as separate specimens.

ASPIRATION:

  • After the skin has been cleaned with alcohol, and if desired, anesthetized with a subcutaneous lidocaine injection, the mass should be stabilized with your non-dominant hand between your thumb and forefinger.
  • Introduce the needle through the skin and make sure that the plunger of the syringe is at the "0" cc mark.
  • Advance the needle into the mass.
  • When the needle has entered the lesion, apply suction slowly by pulling back the plunger of the syringe as much as possible.
  • Move the needle back and forth in a staccato motion within the mass several times while maintaining suction; taking care not to remove the tip of the needle from the mass.
  • Release the plunger, then withdraw the needle from the patient.

Note: It is a common mistake to withdraw the needle from the mass while still applying suction. This will cause the aspirated material to flow into the barrel of the syringe, from where it is extremely difficult to extract. If this happens, the entire procedure should be repeated using a new syringe and needle.

  • Apply pressure at the site of aspiration. (This is extremely important particularly when aspirating breast or thyroid masses.)

PREPARATION OF THE SMEARS:

Aspirated material may clot quickly with the lumen of the biopsy needle. Smear preparation of biopsy material should occur without delay once the tissue has been removed from the patient.

  • Detach the needle from the syringe.
  • Fill the syringe with air.
  • Re-attach the needle to the syringe.
  • Label a new microscope slide with two forms of patient identification. Place the bevel of the needle flush against the surface of the glass slide and express a 1-2 pencil eraser sized amount of material from the needle onto the slide.
  • Using a second clean microscope slide labeled with two forms of patient identification, smear the cellular material as if it were a blood smear.
  • Immediately after preparing the smears, place 1 or 2 smears into 95% alcohol spray with an alcohol based cytofixative (Spray-Cyte).
  • Allow the rest of the smears to air-dry.

The entire needle aspiration procedure should be repeated at least two times in order to obtain an adequate sample.

TEST SPECIFIC COLLECTION:

A.     Afirma/ThyroSeq thyroid specimens:

1.      Collection of fine needle aspiration samples of the thyroid for Afirma and ThyroSeq will be outlined in the following procedure.

2.      With prior notification, additional sample(s) can be collected during the FNA procedure and frozen for ancillary testing. When appropriate and ordered by the physician, this frozen sample can be referred to an outside laboratory for specialized analysis. There are two orders available in EPIC EMR, FNA thyroid with reflex molecular testing and FNA thyroid only. The order of FNA thyroid with reflex to molecular testing should be chosen for cases where additional sample is collected for Afirma/ThyroSeq.

 

a.      Materials:

                                                        i.            In addition to routine materials needed for FNA, obtain an Afirma FNAprotect sample vial or ThyroSeq Preserve solution from the cytology laboratory along with associated requisition form. At the very least we need you to select one of the two ICD-10 billing codes, sample collection date, location of nodule, and your physician signature on the order. Refer to Afirma and ThyroSeq package inserts for detailed collection and storage instructions.

 

b.     Collection Method:

i.        After standard FNA preparations, two subsequent FNA passes are obtained and separately rinsed in Afirma FNAprotect or ThyroSeq Preserve solution. A separate tube should be used for each nodule aspirated and labeled accordingly. Label the sample tube with the patients MRN and the provided label from the Afirma order form. Freeze or refrigerate immediately. Notify Cytology that a sample was collected for potential ancillary testing. The specimen will be kept frozen and held until the final interpretation of the FNA is complete.

 

3.      Upon review by the pathologist the report will indicate if Afirma/ThyroSeq testing is appropriate.

4.      The test is only appropriate for an interpretation of “atypical/inconclusive” thyroid nodule.  

5.      Send the completed Afirma/ThyroSeq requisition AND patient insurance information (face sheet) to the Cytology Dept (916)734-3037.

 

B.     Thyroglobulin washout:

1.    The measurement of thyroglobulin (Tg) levels in FNAB wash specimens from lymph nodes, is a useful adjunct test to cytology for cases suspicious for recurrent/metastatic PTC.

2.    A separate Tg washout protocol, per anatomical site biopsied, must be performed. Never pool more than one biopsy site into a single specimen. 

3.    Acceptable specimen volume range is 0.5 -1.5 mL.

4.    The minimum ratio of specimen to saline is 1 FNA pass / 0.5 mL saline.

 

a.      Materials:

                                                        i.            Plain 3 mL red top vacutainer tube.

                                                      ii.            Sterline saline. Saline is the only acceptable solution to collecting needle washings for Tg testing.

                                                    iii.            Sterile, Luer lock disposable syringe.

                                                    iv.            Ice (provided by ultrasound department).

                                                      v.            Requisition.

                                                    vi.            Biohazard plastic bag.

 

b.     CollectionMethod:

                                                        i.            Remove the cap from the new/empty plain 4 mL red top vacutainer tube. Place the cap top side down onto a clean paper towel. Place the red top tube into the rack holder. 

                                                      ii.            Transfer 1.0 mL of normal, sterile saline into the 4 mL red top vacutainer tube. This will be the reservoir of saline to wash the needle rinse(s) during the procedure.

                                                    iii.            Open a new Luer lock disposable syringe.

                                                    iv.            After each FNA pass has been collected and needle contents expressed onto microscope slide(s) for cytologic analysis, rinse each pass with the 1.0 mL of saline by aspirating up the saline into the needle and syringe and returning the saline to the 4 mL red top vacutainer tube.

                                                      v.            Repeat step iv for each FNA pass.

                                                    vi.            Once all passes are collected and washed, re-cap the 4 mL red top tube.

                                                   vii.            Place the tube into a biohazard transport bag.

                                                 viii.            Place the tube + bag into another biohazard bag containing ice for transport to SARC.

                                                     ix.            Call SARC (4-0500) and SENDOUTS (4-5888)

Unacceptable conditions:

o   Viscous or bloody specimens,

o   Specimens collected in EDTA plasma.

o   Specimen less than 0.5 mL.

o   Specimens greater than 1.5 mL.

 

ALTERNATIVE SUBMISSION METHODS:

The aspirated material may be submitted by rinsing the needle contents into formalin or Saccomanno fixative. Both fixatives are available from the Cytology laboratory. In case RPMI is used as a collection medium, the material should be immediately transported to SARC. If collected after hours, the specimen should be refrigerated until the next courier pickup. For offsite PCN locations, the needles can be rinsed into formalin or Saccomanno fixative and submitted to the laboratory with the appropriate laboratory requisition and clinical information.

Completing the FNA Specimen Requisition

In addition to the clinical history and clinical impression, please provide whether the mass is fixed or mobile, describe the appearance of the overlying skin, the resistance of the tissue to the aspirating needle, and whether you felt that you adequately stabilized and penetrated the mass.

Fine-needle aspiration biopsies of deep visceral or non-palpable masses

Deep or non-palpable masses are sampled under image guidance, such as CT, ultrasound, or fluoroscopy. These procedures are scheduled through the Department of Radiology. The FNA service should be notified so that Cytology staff can be present to prepare smears and perform Rapid On-Site Evaluation (ROSE) of the procured material. This service is available from 07:30-1700, Monday-Friday. Please call 916-734-3031 for this service. Outside of regular operating hours, please contact the Anatomical Pathology Pathologist or Resident on call by contacting the hospital operator.