Impact of a multidisciplinary approach to ultrasound- guided thyroid fine-needle aspiration biopsy at Tygerberg Hospital, Cape Town, South Africa: A retrospective audit.

BACKGROUND: Thyroid nodules are common and mostly benign. Inadequate sampling generally occurs in 13 - 17% of thyroid fine-needle aspiration biopsies (FNABs), but the proportion was found to be as high as 45% on evaluating 100 ultrasound (US)-guided FNABs in a previous unpublished audit at Tygerberg Hospital, Cape Town, South Africa (SA). OBJECTIVES: Primary aim: To determine the diagnostic yield of US-guided thyroid biopsy after implementing changes to existing practices, involving the creation of a specialised clinic and applying protocols for referral and FNAB. Secondary aim: To compare the results with other centres in SA. METHODS: A retrospective audit of 178 thyroid biopsies was conducted. All US-guided thyroid biopsies performed in the specialised clinic between January 2017 and July 2018 were included. Data were analysed using descriptive statistics. RESULTS: The 178 nodules were biopsied in 159 patients. The mean age was 53.7 years, with a gender ratio of 9.6:1 (female/male). A reduction in non-diagnostic biopsies was noted compared with the historical cohort (45% v. 32.6%). Sixty-one nodules (34.3%) had previously been biopsied with inadequate cytology results. When repeat biopsies were excluded, only 16.2% (n=19) were classified as insufficient. CONCLUSIONS: These findings illustrate the importance of the multidisciplinary approach and standardisation of the US-guided biopsy procedure and the value of consistency and quality control in a health system. While nodular thyroid disease is common and FNAB is relatively simple, early referral to a central specialised unit to minimise the incidence of inadequate FNAB should be considered.