Aims: This study was designed in an attempt to Improve the sensitivity
of cytologic examination of fineneedle aspiration biopsies. Methods a
nd Results: A prospective study was carried out on 79 patients with br
east lesions less than 1 cm in diameter and clinically impalpable who
were referred to the Radiodiagnostics Section of the Ca' Granda Hospit
al of Milan in 1990 and 1991 for mammographic and ultrasound verificat
ion. The examination was carried out using a high frequency (10 MHz) u
ltrasound probe to which an aspiration needle had been soldered. This
made it possible to quickly and accurately reach the target nodule and
thus gave a high sensitivity of the examination (93%). However, attac
hment of the needle to the probe prevented sampling from other points
of the nodule and was responsible for the slight Increase in number of
inadequate samplesfi which in turn worsened the specificity of the te
st (86%). To check the gold standard of the examination, all the patie
nts with positive or doubtful aspirations underwent surgical biopsy, w
hereas strict radiologic controls were performed in the negative cases
. Conclusions: Ultrasound-guided fineneedle aspiration may have advant
ages over needle aspiration performed with the stereotactic radiologic
technique. The needle can be monitored even if the patient moves; eve
n deep, peripheral nodules as well as those near a prosthesis can be r
eached; repeated samples can be taken, and costs are limited.