Audit of repeat fine needle aspiration cytology – reasons demystified – a retrospective analytical study in a tertiary care hospital

Abstract

Introduction: Fine needle aspiration cytology (FNAC) is a valuable diagnostic tool in evaluation of mass lesions. One of the major limitations of FNAC is the need for repeat aspiration which imposes workload on the laboratory and stress on the patient as well as on the aspirator. There are only few studies which have focused on the issue of repeat aspiration especially the factors associated with repeat FNAC. Aim: Present study was conducted with the aim to determine the factors associated with repeat FNAC. Materials and Methods: This was a retrospective, analytical laboratory audit of 350 repeat FNAC over a duration of two years. Age, sex, site of FNAC, reasons for repeat and outcome of repeats were recorded. Reason for repeat and final outcome of repeat FNAC were considered as outcome measures. Results: Repeat FNAC accounted to 20.94% (350/1671) of all FNAC performed. Maximum number of repeat FNAC were from thyroid 96/351 (27.4%) followed by soft tissue 86 (24.6%) and breast 81(23.1%). The outcome of repeat FNAC were diagnostic in 279 (79.7%), non-diagnostic 47 (13.4%) and loss of patient follow-up in 24 (6.9%) cases. Reasons for repeat were inadequate aspirates in 223 (63.7%), nonrepresentative material in 118 (33.7%) and suspicious cells to be repeated in 9 (2.6%). Logistic regression analysis revealed that organ of FNAC, month of FNAC and reason for repeat FNAC were independent variables linked with outcome of FNAC. Conclusion: FNAC as an investigative modality has immense diagnostic utility and this potential is fettered by inadequate aspirates and descriptive reporting in certain cases. The tricky cases were often encountered in thyroid, soft tissue and breast lesions. Regular audit of repeat FNACs gives us an insight into conditions where a diligent and meticulous approach is required. Keywords: Fine needle aspiration, Cytology cytology in low resource setting.