The Association of 'GOOP' on Gross Examination of Fine Needle Aspiration Samples and On-Site Adequacy

Background: Rapid on-site cytologic evaluation (ROSE) is not always available for fine needle aspiration (FNA) specimens. We have examined the relationships between the presence of “GOOP” (defined as gooey white material) on FNA aspirates, on-site adequacy (OSA), and diagnosis. Methods: Consecutive FNA samples obtained over the study interval were included. Samples were assessed macroscopically for the presence or absence of GOOP (GOOP+ or GOOP−). GOOP+ samples were further characterized as shiny (G+S) or cheesy (G+C). Gross descriptors were correlated with OSA and final diagnoses. Results: Of the 204 sites biopsied, 102 were malignant, 94 benign, and 8 nondiagnostic. The presence of GOOP was highly predictive for adequacy (positive predictive value 98%). While these correlations for GOOP positivity were significant, the absence of GOOP did not rule out adequacy or malignancy. The presence of GOOP was also significantly correlated with a malignant diagnosis. Conclusions: We have prospectively demonstrated that the presence of GOOP correlates strongly with adequacy. This may be of value for those for whom ROSE is not available and, when available, may help prioritize specimens for on-site review.