Accuracy, predictability and prognostic implications of fine‐needle aspiration biopsy for parotid gland tumours: A retrospective case series

Abstract

Objective To evaluate the precision and utility of fine‐needle aspiration (FNA) in differentiating between benign and malignant parotid tumours, and the implications of FNA results on management and outcomes. Design Retrospective case series. Setting Tertiary medical centre. Participants All adults who underwent preoperative FNA, followed by postoperative histological examination, between 1986 and 2014. Main outcome measures Differences in clinical management and outcomes of patients with parotid masses in light of FNA results. Results We analysed 505 samples from 485 patients. According to histopathological results, preoperative FNA successfully identified benign tumours in 89% of the cases (362/405) and only 59% of malignant tumours (59/100). Overall sensitivity and specificity of FNA in distinguishing between different subtypes of benign lesions were 80% and 99%, respectively, whereas positive predictive value (PPV) and negative predictive value (NPV) were 85% and 98%. Moreover, malignant lesions subtyping had high false‐positive and false‐negative rates with sensitivity, specificity, PPV and NPV of 44%, 100%, 75% and 99%, respectively. Additionally, when FNA falsely classified malignant tumours as benign, surgeries were inappropriately delayed and the durations of surgeries and hospitalisations were shorter, compared to true malignant FNA results. Interestingly, survival was not affected in falsely benign lesions that were mostly low‐grade, conversely non‐diagnostic FNA for malignant tumours resulted in decreased survival. Conclusions Our findings highlight the limitations of FNA as a decision‐making tool in preoperative evaluation of parotid masses. Clinicians should take into account that FNA is inaccurate for identifying specific subtypes of malignant lesions, which may eventually delay treatment and influence outcome.

Rapid on‐site evaluation improves diagnostic performance of fine‐needle aspiration cytology for salivary lesions: Comparison of data from two cancer centers in southern China

“…In our series, AUS and SUMP comprised 3.6% and 7.8% of the aspirates, respectively, which is consistent with the reports (2.8%-11.5% for AUS, 5.9%-21.5% for SUMP). 24,[26][27][28][29][30][31][32][33][34] Comparing the category distribution between the two cancer centers in our series, we found that the SUMC series had higher AUS and lower SUMP distributions than JXCH did. Diagnostic efficacy of FNAC for salivary gland lesions is calculated based on determinate categories including NN, BN, SM, and M. As listed in Table 6, the ranges of ROM in NN, BN, SM, and M are 4.4%-22.0%, 2.2%-25.0%, 66.7%-100%, and 91.3%-100%, respectively, which fall in the implied ROM by MSRSGC panel.…”

“…3 A wide range of ROM has been reported regarding AUS (17.0%-37.5%) and SUMP (24.6%-62.0%). 24,[26][27][28][29][30][31][32][33][34] It is recommended that AUS cases should undergo repeat FNAC or surgery, and surgery should be considered for patients with SUMP category because of their high ROM. Fortunately, distribution of these two categories are relatively lower than the other categories.…”

Ability for fine needle aspiration and frozen section to predict extent of parotidectomy

“…Prior studies exploring FNA's ability to distinguish benign and malignant neoplasms suggest a sensitivity and specificity between 33%–100% and 67%–100%, respectively 6 . However, there is considerable controversy surrounding the utility of FNA due to its high false negative rates reported in the literature 7,8 …”

“…6 However, there is considerable controversy surrounding the utility of FNA due to its high false negative rates reported in the literature. 7,8 Although FNA can provide useful preoperative information, some studies suggest FNA alone is insufficient for proper surgical decision-making and advocate for the use of intraoperative frozen section because of its superior accuracy in detecting malignancy and tumor subtyping. 9 Frozen section also has the added benefits of allowing intraoperative analysis of surgical margins 10 and whether a neoplasm is a benign or a low-or highgrade malignancy.…”

Differentiation of Benign From Malignant Parotid Gland Tumors Using Conventional MRI Based on Radiomics Nomogram

“…Fine-needle aspiration (FNA) biopsy is a common preoperative examination method for parotid neoplasms. However, FNA has some disadvantages, such as high rates of insufficient diagnostic aspirations and the risk of facial nerve palsy ( 6 , 7 ). Magnetic resonance imaging (MRI) has the characteristics of noninvasive multidirectional imaging and high soft-tissue resolution, which is important when evaluating parotid gland tumors.…”