Evolution of fine needle aspiration cytology in the accurate diagnosis of pancreatic neoplasms.

In the era of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), a minimally invasive, safe, and accurate cytologic examination of a variety of intra-abdominal neoplasms has become possible. To assess the efficacy of EUS-FNA for diagnosis of primary pancreatic tumors, a 10-year retrospective review of a consecutive series of patients diagnosed between 1996 and 2005 was undertaken. Comparisons were made between early (1996-2000) and late (2001-2005) periods regarding diagnostic modalities used and the concordance of EUS-FNA cytology with macroscopic tissue histology. Although macroscopic biopsy diagnostic yield did not change over time, yield from EUS-FNA increased from 40 per cent to 95 per cent (P = 0.001). Because of improved accuracy of FNA cytology, only six per cent of tumors required additional macroscopic tissue histology in the late period versus 35 per cent in the early period (P = 0.001). There was 100 per cent concordance between the cytologic and histologic diagnoses in the late period versus only 33 per cent in the early period (P = 0.032). We conclude that (1) the frequency of pathologically diagnosed pancreatic tumors doubled over 10 years, (2) utilization of EUS-FNA significantly increased the accuracy of cytologic diagnosis, and (3) as a result, the need for macroscopic tissue biopsy for diagnosis of pancreatic neoplasms has been obviated.