Publication:

A study of the diagnostic effectiveness of repeated fine needle aspiration in thyroid and breast lesions

Background Fine needle aspiration cytology (FNAC) is a relatively safe diagnostic tool with high sensitivity and specificity. Due to lesion inherent properties and lack of proper technique, adequate cellularity is not yielded in some instances, resulting in an inconclusive report. In such instances we have to go for repeat FNA to make a proper diagnosis. Repeat aspirations impose unnecessary workload on the lab and are distressful to the patients. The issue of repeat aspiration is largely unaddressed. Objectives were to identify the proportion of repeated fine needle aspirations in breast and thyroid lesions turning out to be diagnostic and to identify and describe the common factors leading to repeat fine needle aspiration.

Methods 190 cases of repeated FNA including both thyroid and breast lesions are included in the study. FNA done after an initial aspiration with inconclusive smear is considered as repeated FNA. History, clinical examination findings, findings in imaging studies, nature of aspirate obtained for each patient advised repeat FNA, are recorded. Proportion of repeat FNAs turning out to be diagnostic and the documented reasons for repeat were taken as the outcome measure.

Results 78% of repeat FNA in thyroid lesions and 50% of the repeat FNA in breast lesions were diagnostic. Inadequate cellularity, haemorrhagic aspirate and cystic change are the most common factors leading to repeat FNA.

Conclusions Since thyroid and breast are the most common sites where FNA is done and 64% of the total lesions are diagnostic, repeat FNA in all other sites are likely to yield a similar diagnostic outcome. Hence, repeat FNA is advisable in lesions which had initial non diagnostic result.