To analyze the value and limitations of fine needle aspiration (FNA) cytology in a rural setting. Prospective analysis of 1,196 FNA cytology results of superficial and deep masses from 1,088 patients in rural New South Wales, Australia, between September 1990 and May 1996. The FNA procedures were performed by palpation and image guidance using various-gauge needles and core biopsies as appropriate. FNA cytology results were analyzed, based on body organs and cytomorphologic findings. Breast, 450 (41%); thyroid, 152 (14%); superficial lymph nodes, 150 (14%); lung, 98 (9%); and liver, 55 (5%), made up the majority of the cases. The following general cytologic categories were used: nonrepresentative (inadequate), 39 (3.58%); benign, 662 (60.85%); atypical, 45 (4.13%); suspicious, 30 (2.76%); and malignant, 312 (28.68%). Clinical and histologic follow-up (core biopsies in 100 patients and histology of the atypical, suspicious and malignant cytologic categories in 387 patients) showed over 96% sensitivity for a diagnosis of malignancy, with about a 4% false negative rate and 99.04% predictive value of a malignant FNA diagnosis. The false positive rate in the cytologically malignant group of 312 patients was 0.96%. The breast, thyroid and lymph node fine needle aspirations were mostly benign. The great majority of deep organ fine needle aspirations were malignant. Atypical and suspicious FNA cytology, seen in both superficial and deep sites, was due to either technical difficulty in obtaining material or problems of interpretation (genuine cytologic overlap or inexperience). The radiologically suspicious cases with negative cytology were either reaspirated or subjected to surgical biopsy. FNA cytology, when practiced in a multidisciplinary setting with direct involvement of pathologists, radiologists and clinicians, is an extremely accurate, well-tolerated, relatively noninvasive and low-risk test that obviates the need for surgical intervention in most benign conditions and disseminated malignancies. Therefore, by taking an active role with on-site assessment of the FNA material and discussion with radiologic colleagues, the cytopathologist could offer an FNA service comparable to surgical pathology in sensitivity and very similar to frozen section in specificity.

To compare, contrast and analyze the value and limitations of fine needle aspiration (FNA) cytology and core biopsy (CB) in a rural setting. Retrospective analysis of 100 FNA cytology and 100 CB results of mass lesions from 193 patients matched for age, sex and body organs, and referred for FNA or CB in rural New South Wales, Australia, between September 1990 and May 1996. FNA cytology and CB results from 193 patients were analyzed, based on anatomic location and cytologic criteria. Sites included lung, retroperitoneum, liver, breast, kidney, pancreas and ovary. The FNA group contained 6 inadequate, 14 benign, 3 atypical, 6 suspicious and 71 malignant cases, whereas the CB group had 1 inadequate, 24 benign and 75 malignant conditions. The inadequate samples in both groups were due to technical difficulty in obtaining representative material. The indeterminate (atypical and suspicious) group, which was the main pitfall of FNA, contained 4 low grade carcinomas, 3 low grade non-Hodgkin's lymphomas and 2 fibrocystic breast changes. The benign FNA group comprised 8 cysts, 5 inflammatory/reactive conditions and 1 benign tumor/hamartoma, whereas the benign CB group contained 11 cysts, 9 inflammatory/reactive conditions and 4 benign tumors. FNA was comparable to CB at most anatomic sites. CB occasionally offered additional information. This slight advantage was due to the availability of tissue from the first and often the only pass for assessment of architecture and performance of ancillary tests, which obviated the need for further sampling. On-site assessment of the core imprints at the time of the procedure by the highly skilled and experienced interventional cytopathologist was responsible for limiting the number of attempts to one core in most of the instances, therefore minimizing complications. Pathologists are encouraged to become more familiar with the criteria of aspiration cytology, which has proven its validity in the new cost-conscious environment. Despite the recent surge in the popularity of core biopsy, FNA cytology, when practiced in a multidisciplinary setting, with involvement of pathologists, radiologists and clinicians, is an extremely accurate test with very high sensitivity, which approaches that of surgical pathology, and specificity very similar to that of frozen section. FNA has a positive predictive value for a malignant diagnosis of almost 100%. FNA is a well-tolerated, relatively noninvasive test with a very low risk of complications.

To audit and evaluate the pitfalls in renal fine needle aspiration (FNA) cytology. A retrospective analysis of 180 renal FNAs from 163 patients, encountered at Canberra Hospital, Australian Capital Territory, between June 1989 and July 1997 was undertaken. The FNA procedures had been performed by radiologists under computed tomography (CT) or ultrasound (US) guidance. The study correlated the FNA results with biopsy findings and clinical outcome. The initial cytologic diagnoses included 84 (47%) benign, 6 (3%) atypical, 7 (4%) suspicious, 70 (39%) malignant and 13 (7%) inadequate. Six of the 13 cytologically inadequate group, on further investigation, had malignant histology. The benign cytologic categories contained 79 benign conditions and 5 cases with a malignant outcome. The atypical cytologic group contained 5 benign and 1 malignant case. All nine cytologically suspicious cases had malignant histology. The cytologically malignant group contained 62 malignant, 7 benign and 1 patient lost to follow-up. The sensitivity was 92.5%, specificity was 91.9%, positive predictive value was 89.9%, negative predictive value was 94.0%, and efficacy of the test was 92.2%. Renal FNA can provide an accurate diagnosis in most instances; however, aspiration cytology of the kidney has limitations and pitfalls. Low grade renal cell carcinoma has to be differentiated from oncocytoma, angiomyolipoma, renal infarct and reactive conditions. Renal FNA has a high negative predictive value, which is useful in reassuring patients with radiologically and cytologically benign lesions. Negative FNA does not exclude malignancy in the presence of a radiologic suspicion.