Adequacy assessment of endoscopic ultrasound-guided, fine-needle aspirations of pancreatic masses for theranostic studies: Optimization of current practices is warranted

Context.-Novel chemotherapy regimens now provide the opportunity for "personalized" care in pancreatic cancer. Little is known about our ability to procure adequate cells for theranostic studies using standard ultrasound-guided fine-needle aspirations and cytologic techniques. Objective.-To assess cellularity of cytology material in patients with solid pancreatic lesions. Design.-One hundred sixty-nine endoscopic ultrasound- guided fine-needle aspirations with positive diagnoses of solid epithelial pancreatic neoplasms were evaluated for smear and cell block cellularity. Cellularity was scored on a scale of 1 to 4; scores of 3 or 4 (>100 cells) were deemed adequate for ancillary studies. Clinicopathologic variables were recorded. A 3-month prospective analysis was also performed using a new collection algorithm. Results.-Only 12.4% (21 of 169) of the positive cases had a cell block cellularity score that was adequate for theranostic studies. This score was not associated with onsite evaluation, needle gauge, or number of passes. Adenocarcinoma was the most common diagnosis (88%) but yielded fewer adequate cell blocks, P = .006. Cellularity showed correlation with endoscopists, P = .04. Tumor size and fibrosis score of resected tumors tended to correlate with cellularity, but only larger size in endocrine tumors was significantly associated with adequacy (P = .02). Standardized collection did not improve overall cell block cellularity. Conclusions.-Changes in practice, such as obtaining dedicated passes for ancillary studies, may not be enough to improve the theranostic utility of endoscopic ultrasound- guided fine-needle aspiration in pancreatic neoplasia. Other methods to improve tumor cell yield, including modified cytologic techniques and new needle designs, need to be further investigated.