The effect of aspiration during FNAC of the thyroid on adequacy of cytologic material

Fine needle aspiration cytology (FNAC) is the current investigation of choice
for nodules of the thyroid. It differentiates benign from malignant nodules and
thereby selecting nodules for surgery. Major disadvantage of the procedure is
the rate of inadequate or non-diagnostic specimen, resulting in diagnostic
delay and discomfort for patients and increases costs for the institution.
Ultrasound-guided FNAC is frequently advised as the procedure of choice in
international literature. It is also advised in literature to frequently
perform quality control in ones own institution.
Recent quality research in the UMC Utrecht, (manuscript submitted to American
Journal of Clinical Pathology) showed a high percentage of inadequate
ultrasound-guided FNAC specimen. Our investigation showed better results when
radiologist performed aspiration during the procedure. It is still
controversial in literature which method, aspiration versus non-aspirations
yields the best results. Only two studies (Romitelli and Degirmenci) showed a
better result of the non-aspirating capillary technique. (1;2)
In order to minimize costs and provide better health care, we would like to
optimize the FNAC procedure, resulting in less inadequate specimens. In order
to do so, we would like to identify which factors influence the adequacy rate.
As advised by multiple studies we would like to, train puncturing specialist in
identifying thyroid cells microscopically, so that onsite adequacy assessment
can be performed.
Our hypothesis is: Aspiration during FNC and onsite cytologic assessment by the
aspirator (=puncturing specialist) can be performed successfully and reduces
the rate of inadequate (or non-diagnostic) specimen drastically.

Our goal is to evaluate if this onsite assessment and aspiration during
punction reduces inadequacy of specimens and see if onsite assessment by the
aspirator is performed accurately after a brief instruction by a
cytopathologist.

Primary Objective:
Evaluation of the effect of aspiration on cytologic adequacy of fine needle
aspiration of thyroid tissue.

Secondary Objective(s):
Identifying factors associated with cytologic adequacy of FNAC specimens
The effect of onsite interpretation on adequacy rate
To see if onsite interpretation of FNAC specimens of the thyroid can be
performed accurately by the specialist also performing the punction (in this
case: radiologist and residents).

The study design is that of a prospective cohort study. The study will be
performed at the outpatient clinic where patients with thyroid nodules will be
clustered on a specific day.

Every adult patient eligible for FNAC punction is also eligible for inclusion.
Informed consent can be obtained after careful instructions and documented
information after 2 weeks after the first policlinic visit.

After inclusion every patient will be randomized for a procedure. Smears will
be carefully examined by the aspirator for material adequacy. Repeat punctions
will be performed until the aspirator judges the material to be sufficient for
definitive pathological analysis. All smears are send to the pathology
department were they will be judged again on cytologic adequacy.

When material, after definitive cytopathologic examination is being judged as
adequate, no further punctions will be performed unless regular follow-up with
FNAC is required/advised.
When the material is judged inadequate after cytopathologic examination, the
patient will have to undergo a repeat punction and will be again randomized for
one of the two methods.

Data concerning patient, nodule, results of ultrasound, puncturing specialist,
results of FNAC, results of onsite assessment and cytopathological analysis and
final histology or follow-up will be obtained.

Cytopathologist will be blinded for the aspiration and non-aspiration smear.
The aspirator will have to follow a short course provided by the pathology
department to learn to identify thyreocytes microscopically.

Possible questionnaires will be distributed during hospital visit. There is no
need for the patients to attend the hospital outside regular controls.

For now, the study period will be 2 years, with analysis of preliminary data
after a year. In this period we expect to include more than enough patients
for statistical significant outcomes.

When the best practise concerning FNAC is established, patients will have to
undergo less punctions. Data from 1998 to 2008 showed a rate of inadequate FNAC
specimen in the University Medical Center Utrecht of 46.2%. Repeated FNAC to
reach an adequate specimen can be prevented. Thereby factors like patient
discomfort, diagnostic delay, doctor*s frustration and costs for the
institution can be reduced. Because of randomisation and inclusion of all
patients eligible for thyroid FNAC results of this study can be generalised for
a broader population.
There is no additional risk for the patient participating in this study, and no
additional visits to the hospital have to be made.