Evaluation of usefulness of fine-needle aspiration cytology in the diagnosis of tumours of the accessory parotid gland: a preliminary analysis of a case series in Japan

Efficacy of ultrasound shear wave elastography in the diagnosis of salivary gland tumors

PURPOSE

Diagnostic accuracy of fine-needle aspiration cytology (FNAC) as the ability to discriminate between the target condition and health in the evaluation of salivary gland tumors is not perfected yet and false-negative results are possible. The purpose of the present study was to measure and compare the diagnostic accuracy of FNAC performed with conventional B-mode ultrasound and ultrasound with shear wave elastography (SWE) FNAC navigation.

METHODS

The investigators implemented a single-blind randomized study (sealed envelope method). The study population was composed of all patients presenting for evaluation and management of suspected benign or malignant tumors of the major salivary glands between July 2013 and December 2020. The involvement of SWE navigation was the primary predictor variable affecting FNA targeting. The method involved analysis of redistribution of SWE values within the affected gland expressed in kilopascals (kPa) and the four-point ES1 (soft tissue) to ES4 (stiff) scoring. The primary outcome variable was the success in obtaining diagnostic tissue resulting in a histologically confirmed FNAC diagnosis and coded as yes/no. Age and sex of the patients and topographical locations of lesions were covariates. Descriptive and bivariate statistics were computed and the P value was set at .05.

RESULTS

The sample included 132 subjects (male/female 59/73; mean age 54 ± 11 years; 144 tumors). SWE + Group (n = 66) consisted of patients presurgically diagnosed with salivary tumors SWE-guided FNAC and SWE- Group (n = 66) was diagnosed with tumors by conventional ultrasound-(B-mode)-guided FNAC. The SWE-guided FNAC statistically significantly reduced the incidence of false-negative results (n = 0; P = .001) and nondiagnostic cases (n = 3 SWE FNAC vs n = 7 B-mode US FNAC; P = .04). For SWE + Group, the FNAC diagnosis was confirmed by postsurgical histology in 95.5% with 91.0% sensitivity (confidence interval [CI] 0.62 to 0.97) and 84.4% specificity (CI 0.58 to 0.96). For SWE- Group, 81.8% confirmation was obtained (P = .05) with 82.3% sensitivity (CI 0.54 to 0.90) and 74.0% specificity.

CONCLUSION

SWE can increase success in obtaining diagnostic tissue when used for FNAC navigation purposes. We suggest combining both SWE and standard B-mode US methods when the FNAC procedure is performed.

Management of accessory parotid gland tumours: 32-year experience from a single institution and review of the literature

Accessory parotid gland tumours (APGTs) are very rare. Regarding their anatomical location, an adequate surgical approach is necessary to provide safe resection and satisfactory postoperative results. The aims of this study were to present our tertiary centre experience in surgical treatment and management of APGTs and to review the literature regarding their treatment, particularly in terms of surgical modalities. Data of 13 patients with primarily surgically treated APGTs have been collected and analysed. Well-documented English-literature articles of surgically treated APGTs have been extracted from the PubMed, Scopus and Web of Science databases ending in May 2018, and analysed. Mean age at diagnosis was 41.1 years. The most common benign histological subtype was pleomorphic adenoma (53.8%), while mucoepidermoid carcinoma (23.1%) was most common in malignant counterparts. The malignancy rate was 38.5%. Postoperative results were satisfactory, and the follow-up period was uneventful in all patients except one who died of locoregional recurrence. A total of 57 papers with reported series in APGTs have been identified with a total of 306 APGT cases. From oncological, functional and aesthetic standpoints, approaches through a standard parotidectomy provide satisfactory results.

Pathology and management of masses in the accessory parotid gland region: 24-year experience at a single institution

PURPOSE

Masses in the accessory parotid gland (APG) region are clinically rare and their management can lead to conflicts between the need for tumor resection and facial cosmesis. The aim of this study was to analyze the pathological classifications and management of APG lesions in our hospital.

MATERIALS AND METHODS

From January 1993 to March 2017, 130 patients with primary tumors in the APG region who underwent surgical treatment were enrolled. Follow-up surveys after surgery were then carried out.

RESULTS

Among the 130 patients, 53.8% of lesions were benign (n = 70), 23.8% were malignant (n = 31), 14.6% were vascular malformations (n = 19), 6.15% were sialadenitis (n = 8), and 1.65% were cysts (n = 2). Pleomorphic adenoma accounted for 67.1% of the benign tumors (n = 47). Lymphoma, lymphoepithelial carcinoma, and acinar cell carcinoma topped the list of malignant tumors (5 cases in each group). Surgery and surgery plus radio-chemotherapy were performed for benign and aggressive malignant lesions, respectively. At the time of follow-up, 5-year overall survival was 88.1%; mean follow-up was 139 months (range 3-281 months).

CONCLUSIONS

Masses in the APG region have complicated pathological types. Perfect preoperative preparation, with fine-needle aspiration biopsy and imaging examinations, would contribute to identifying characteristics. Treatment schedules and surgical approaches should be determined according to the cytology reports and frozen-section examinations before and during operation.

Reoperation following the use of non-standardized procedures for malignant parotid tumors

Non-standardized or conservative procedures are employed when parotid tumors involving the facial nerve or parotid carcinoma are misdiagnosed as benign parotid tumors prior to or during surgery. Remedial measures are usually required when the pathological diagnosis of a malignant parotid tumor is confirmed following surgery. The aim of the present study was to systematically evaluate reoperation subsequent to treatment with non-standardized procedures for malignant parotid tumors, and to explore the preoperative diagnoses, the primary procedure selection and the necessity of reoperation following non-standardized procedures in malignant parotid tumors. A total of 30 patients who met the inclusion criteria, were diagnosed with a malignant parotid tumor and underwent reoperation following the use of a non-standardized procedure were included in the present study. Surgical conditions and clinical data were analyzed. Among the patients with a malignant parotid tumor who underwent reoperation subsequent to a non-standardized procedure, the incidence of residual tumor, as confirmed by pathological examination, was 63.3% (19/30). The intact facial nerve preservation rate was 83.3% (25/30), the facial nerve branch resection rate was 6.7% (2/30), the facial partial nerve resection rate was 6.7% (2/30) and the facial nerve resection rate was 3.3% (1/30). In total, 3 patients underwent facial nerve reconstruction, 3 patients underwent a local flap repair of skin defects in the parotid region and 3 patients underwent pectoralis major muscle flap repair. The current findings indicate that the qualitative diagnosis of malignant parotid tumors prior to surgery is difficult, there is a high incidence of residual tumor following non-standardized procedures, and that reoperation in a timely manner is required in such cases.

Factors Influencing the Outcome of Ultrasound-Guided Fine-Needle Aspiration for Salivary Gland Lesion Diagnosis

OBJECTIVES

This study aimed to assess multiple factors influencing the outcomes of ultrasound (US)-guided fine-needle aspiration (FNA) of salivary gland lesions.

METHODS

From 2008 to 2013, a single radiologist performed US-guided FNA of salivary gland lesions in 243 patients. With the exclusion of pure cysts, poor image quality, and insufficient static image cases, 218 salivary gland lesions in 218 patients were included. The composition, size, location, and vascularity of the lesions were retrospectively investigated on the basis of sonographic findings by the same radiologist. The relationship between sampling adequacy and multiple factors was compared, and the diagnostic accuracy of US-guided FNA of salivary gland lesions was calculated by using the final diagnosis as a reference standard.

RESULTS

The sampling adequacy rate for US-guided FNA of the 218 salivary gland lesions was 96.8% (211 of 218). A significant difference was observed in the composition and vascularity of the lesions (P < .0001), whereas there was no significant difference in the patient age and sex, lesion size, lesion location, and needle size. The rate of inadequate sampling increased in predominantly cystic lesions compared with solid lesions as well as in low-vascularity lesions compared with high-vascularity lesions. Of the 218 lesions, 178 (81.7%) were ultimately diagnosed, and most were benign (162 of 178 [91.0%]). When 3 cases with indeterminate cytologic results were excluded, the sensitivity, specificity, positive and negative predictive values, and accuracy of US-guided FNA of salivary gland lesions were 64.3%, 98.8%, 81.8%, 97.0%, and 96.0%, respectively.

CONCLUSIONS

When using US-guided FNA to diagnose salivary gland lesions, sampling adequacy depends on the composition or vascularity of the lesions.