Presentation Description
Institution: Te What Ora Waikato - Hamilton, Aotearoa New Zealand
Aim
To evaluate the sensitivity and specificity of parotid gland freehand (FH) FNA and USS-guided (US) FNA performed at Waikato Hospital, Hamilton, New Zealand.
Methodology
A retrospective review to include patients who underwent FNA of parotid lesion, followed by total or partial parotidectomy at Waikato Hospital from 1/1/2016 to 31/12/2021.
FNA cytology was classified according to the Milan System of Classification (MSC). MSC I, II, III and IVA were considered benign and MSC IVB, V and VI were considered malignant. The final histology result from parotidectomy was classified according to the WHO Classification of Salivary Glands Tumours 2017.
Results
144 patients were included in the study, with a median age of 64 years and a slight male preponderance at 53.4%. Caucasian comprised the biggest patient group at 67.4%. 73 patients (50.6%) had FH FNA and 71 patients (49.3%) had US FNA. Baseline demographics and tumour characteristics were similar in each subgroup.
Overall, 71.5% of all FNAs were benign, and 28.5% were malignant. Overall histology results show a similar ratio of 68.1% benign, and 31.9% malignant parotid lesions.
The sensitivity for malignancy of FH and US FNA was 60.9% and 87.0% respectively. The specificity for malignancy of FH and US FNA was 92.0% and 93.8% respectively.
Both FH and US FNA had lower sensitivity for malignancy in smaller tumours. Higher BMI was also associated with a lower sensitivity of US FNA, although did not impact that of FH FNA. Other factors, including bleeding tendencies and tumour location (deep vs superficial vs mixed), did not significantly affect sensitivity of FNA.
Conclusion
In conclusion, US FNA demonstrated superior sensitivity compared to FH FNA, with similar specificity. Streamlining services to prioritise US FNA is recommended, given its higher diagnostic yield. FH FNA may be considered as an alternative when US FNA is unavailable, particularly for tumours larger than 2 cm, where it offers improved sensitivity.
Speakers
Authors
Authors
Miss Jia Hui Lim - , Dr Hannah Liu - , Prof Behzad Hajarizadeh - , Dr Omid Ahmadi - , Dr James Sanders -