Fine needle aspiration biopsy (FNAB) for lesions of the salivary glands

Application of ultrasound in distinguishing the incipient microtumor from inherent lymph nodes of the parotid glands

BACKGROUND

Parotid microtumors (size ≤ 1 cm) pose a significant clinical challenge due to their malignant potential and risks associated with surgery. It is imperative to explore the diagnostic workflow that incorporates ultrasound (US) in order to make appropriate clinical decisions with minimal invasiveness.

METHODS

The patients receiving both US and ultrasound-guided fine needle aspiration (USFNA) for the parotid microtumors in a medical center were retrospectively recruited. The ultrasonic features, cytology of USFNA, and final surgical pathology were analyzed to differentiate the tumor origins and their malignant potential.

RESULTS

From August 2009 to March 2016, a total of 92 patients were enrolled in the study. The short axis, long-to-short axis ratio, and presence of an echogenic hilum were found to be significantly useful in distinguishing lymphoid tissue origin from salivary gland origin, which was confirmed by USFNA. An irregular border was predictive for malignant parotid microtumors from both origins. Intra-tumoral heterogeneity was also identified as a significant feature associated with malignant lymph nodes. USFNA was able to confirm all malignant lymph nodes, but it had a false negative rate of 8.5% in parotid microtumors of salivary gland origin. Based on the analysis of US and USFNA results, a diagnostic workflow for parotid microtumors was proposed.

CONCLUSION

US and USFNA can be helpful in classifying the origins of parotid microtumors. US-FNA carries the risk of producing false negative results specifically for microtumors originating from salivary glands, but not lymphoid tissue. The diagnostic workflow, which incorporates both US and USFNA, assists in determining the clinical decision for diagnosing and managing parotid microtumors.

Usefulness of ultrasound and fine needle aspiration cytology of major salivary gland lesions

PURPOSE

To assess the clinical value of ultrasound (US) and fine needle aspiration (FNA) of salivary gland lesions prior to surgery, for preoperative decision-making and long-term follow-up/outcome.

MATERIALS & METHODS

We retrospectively analyzed the medical charts of 98 consecutive patients with major salivary gland lesions who were treated in a single medical from 2008 to 2017. Preoperative US and FNA was performed in all patients. Cytology results were compared with histopathological diagnoses. The correlation between preoperative US findings, cytology and histopathological diagnoses was assessed.

RESULTS

Twenty-three specimens were histopathologically malignant, and 75 were diagnosed as benign. Three false-positive results diagnosed as malignant in cytology had a final histology of sialadenitis, pleomorphic adenoma and Warthin's tumor, respectively. In six cases, cytology yielded false-negative results. The overall accuracy of FNA in distinguishing benign from malignant lesions was 91%. Sensitivity was 70% and specificity 93%. There was no significant correlation between US features and final pathology, but larger size had some correlation with malignancy (p = 0.306). No complications were observed during or after performing FNA.

CONCLUSION

FNA from salivary gland lesions is safe and in many cases can help in preoperative decision making or surgical planning. Hence, the results of FNA cytology should have an integral role in clinical decision-making and management of major salivary gland lesions. False-negative results do occur and therefore should be used only as an adjunctive measure.

Risk of high-grade malignancy in parotid gland tumors as classified by the Milan System for Reporting Salivary Gland Cytopathology

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (Milan System) has previously shown its diagnostic utility by categorizing the seven cytology findings in salivary gland lesions. However, there has been lack of study about the risk of high-grade malignancy in the cytology diagnosis based on the Milan System. Thus, we tried to identify the diagnostic ability of the Milan System for high-grade malignancy and to suggest an improved diagnostic approach for preoperative estimation of high-grade malignancy using the Milan System.

METHODS

A total of 413 patients with parotid gland tumors, who had undergone surgical resection from 2011 to 2015 were included in the present study retrospectively. Cytopathology was reclassified according to the Milan System by two independent reviewers. The outcomes were risk of malignancy and risk of high-grade malignancy. The diagnostic performance of the Milan System category [Malignant] for detecting high-grade malignancy was calculated.

RESULTS

The risk of malignancy was 83.3% and 100% in the Milan System categories [Suspicious for Malignancy] and [Malignant], respectively. Meanwhile, the risk of high-grade malignancy was 16.7% and 55.9% in these two categories. Disease-free survival of patients with high-grade malignancy was significantly worse than those with low- and intermediate-grade malignancy. Union combining the Milan System category [Malignant] with the presence of nodal metastasis suggested high-grade malignancy with an acceptable diagnostic sensitivity (0.889-0.963) and negative predictive value (0.900-0.966).

CONCLUSIONS

The Milan System category [Malignant] with the presence of nodal metastasis suggested parotid gland tumors as high-grade malignancy in a pretreatment setting.

Cytology of the Salivary Glands

Common usage of fine-needle aspirate (FNA) for salivary gland lesions is the preoperative determination of whether a lesion is neoplastic, its lineage, and if neoplastic, whether it is low grade/benign, or high grade. Immunohistochemical stains can be performed on cell blocks to determine lineage and help refine diagnosis, although their performance is not always equivalent to that seen in surgical specimens. Several characteristic translocations have been described in various entities in these categories, and these can be evaluated using fluorescence in situ hybridization. In the future, high-throughput next-generation sequencing panels may further refine cytologic diagnosis in salivary tumors.

Sensitivity, Specificity, and Posttest Probability of Parotid Fine-Needle Aspiration: A Systematic Review and Meta-analysis

OBJECTIVES

(1) To analyze the sensitivity and specificity of fine-needle aspiration (FNA) in distinguishing benign from malignant parotid disease. (2) To determine the anticipated posttest probability of malignancy and probability of nondiagnostic and indeterminate cytology with parotid FNA.

DATA SOURCES

Independently corroborated computerized searches of PubMed, Embase, and Cochrane Central Register were performed. These were supplemented with manual searches and input from content experts.

REVIEW METHODS

Inclusion/exclusion criteria specified diagnosis of parotid mass, intervention with both FNA and surgical excision, and enumeration of both cytologic and surgical histopathologic results. The primary outcomes were sensitivity, specificity, and posttest probability of malignancy. Heterogeneity was evaluated with the I(2) statistic. Meta-analysis was performed via a 2-level mixed logistic regression model. Bayesian nomograms were plotted via pooled likelihood ratios.

RESULTS

The systematic review yielded 70 criterion-meeting studies, 63 of which contained data that allowed for computation of numerical outcomes (n = 5647 patients; level 2a) and consideration of meta-analysis. Subgroup analyses were performed in studies that were prospective, involved consecutive patients, described the FNA technique utilized, and used ultrasound guidance. The I(2) point estimate was >70% for all analyses, except within prospectively obtained and ultrasound-guided results. Among the prospective subgroup, the pooled analysis demonstrated a sensitivity of 0.882 (95% confidence interval [95% CI], 0.509-0.982) and a specificity of 0.995 (95% CI, 0.960-0.999). The probabilities of nondiagnostic and indeterminate cytology were 0.053 (95% CI, 0.030-0.075) and 0.147 (95% CI, 0.106-0.188), respectively.

CONCLUSION

FNA has moderate sensitivity and high specificity in differentiating malignant from benign parotid lesions. Considerable heterogeneity is present among studies.

Verification bias in diagnostic accuracy studies for fine- and core needle biopsy of salivary gland lesions in otolaryngology journals: a systematic review and analysis

BACKGROUND

Diagnostic test accuracy (DTA) studies for needle biopsy are frequently published in otolaryngology journals, but this body of literature has not been assessed for verification bias.

METHODS

We conducted a systematic review of DTA studies on needle biopsy of salivary gland lesions appearing in otolaryngology journals. Studies were assessed by 2 reviewers for verification bias.

RESULTS

We identified 95 DTA studies for needle biopsy of salivary gland lesions. Eighty-one studies (84%) had verification bias. Five of the biased studies provided sufficient data to estimate the extent of bias. Verification bias was associated with an overestimate of sensitivity and an underestimate of specificity. Studies on core needle biopsy (CNB) had a lower rate of verification bias than fine-needle aspiration (FNA) studies.

CONCLUSION

Verification bias is common in DTA studies of needle biopsy for salivary gland lesions published in ear, nose, and throat (ENT) journals. Such studies overestimated sensitivity and underestimated specificity.

Quality Appraisal of Diagnostic Accuracy Studies in Fine-Needle Aspiration Cytology: A Survey of Risk of Bias and Comparability

Context.—The quality of diagnostic accuracy studies is determined by 2 key factors: risk of bias and comparability. Bias can distort accuracy estimates and poor reporting impairs comparability. While diagnostic accuracy studies for fine-needle aspiration cytology (FNAC) are frequently published, the methodologic issues associated with this body of literature have never been reviewed.

Objective.—To assess the quality of design and reporting of diagnostic test accuracy studies in FNAC.

Data Sources.—Diagnostic accuracy studies were identified by a Medline (US National Library of Medicine) search. Sixty-four FNAC diagnostic test accuracy studies were randomly selected for structured review with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) survey. Studies were divided between 2 time periods: 2000-2001 and 2009-2011.

Conclusions.—Diagnostic test accuracy studies of FNAC suffer from numerous deficiencies in study design, which negatively affect the reliability of accuracy estimates.

Diagnosis and treatment outcomes for patients with lymphoma of the parotid gland

OBJECTIVES/HYPOTHESIS

Lymphoma of the parotid gland (LPG) is a rare disease. Clinical diagnosis is difficult, due to a lack of specific symptoms and findings. The aim of this study is to evaluate the diagnostic workup based on the analysis of our cases of LPG and to present the stage-dependent treatment outcome.

STUDY DESIGN

Retrospective case-control study.

METHODS

From 1992 to 2008, 697 patients at our institution underwent surgery because of a parotid tumor. Among 246 malignancies, an LPG was found histologically in 28 cases (4%). Staging was performed according to the Ann Arbor classification, and treatment was performed by radiotherapy and/or chemo/immunotherapy. The patients were retrospectively analyzed.

RESULTS

No specific symptoms were found, with the main finding being a unilateral, painless, slowly progressing parotid mass. The sensitivities of imaging and fine-needle aspiration cytology in detecting LPG were 41% and 12%, respectively. Histology was the key to diagnosis, and frozen sections often revealed the diagnosis during surgery, which obviated the need for more extensive surgery in 89% of cases. The 5-year disease-specific survival estimates were 100% and 75% for early tumor stages (I and II) and advanced stages (III and IV), respectively.

CONCLUSIONS

When the precise nature of a parotid mass remains obscure after fine-needle aspiration cytology and imaging, but LPG is clinically suspected, surgical tissue sampling with frozen sections appears to be a valid option and can prevent the need for more extensive surgery. The treatment outcome for LPG is favorable.

Review of salivary papers published in the British Journal of Oral & Maxillofacial Surgery during 2009-2010

The management of salivary gland disease forms an appreciable part of the work undertaken by our specialty. Fast-track and one-stop clinics for head and neck lumps allow for early diagnosis of salivary gland tumours in most units, and for the sharing of cases between our ear, nose and throat (ENT) colleagues. The emphasis on benign salivary gland disease is very much on outcome after operation, and there have been improvements in surgical technique, particularly in relation to minimal dissection of salivary adenomas and sialendoscopy. This article continues a series of reviews, which aim to provide readers with a quick overview and update of recent publications in the British Journal of Oral and Maxillofacial Surgery (BJOMS) within a particular subspecialty.

Fine needle aspiration biopsy in the oral cavity and head and neck region

The objective of the current study was to evaluate the sensitivity, specificity and accuracy of fine needle aspiration biopsy (FNAB) of submucous nodules from the oral cavity and head and neck region as an auxiliary diagnostic tool. Fifty patients with nodule lesions in the oral cavity and the head and neck region were selected. All of them were submitted to FNAB and to either incisional or excisional biopsy. The diagnoses from the FNABs were compared with the biopsy diagnosis as the gold standard. All the cases of FNAB were analyzed by a single oral pathologist prior to the biopsy diagnosis. The results showed that the sensitivity of FNAB was 75%, its specificity was 96% and its accuracy was 58.8%. The false positive and false negative rates were 6.7% and 13.3%, respectively. The positive predictive value was 86% and the negative predictive value was 93%. The inconclusive rate was 16/50. FNAB displayed a high success rate for identifying both malignant and benign lesions, but a low accuracy for making a final diagnosis.

Fine-needle aspiration cytology: a reliable tool in the diagnosis of salivary gland lesions

BACKGROUND

Fine-needle aspiration cytology (FNAC) is used as the main initial diagnostic investigation for lumps in the head and neck region. Major salivary glands and some minor salivary glands are easily accessible; therefore, they are optimal targets for FNAC. The aim of this study was to discuss the advantages and pitfalls of FNAC as compared to histopathology in the salivary gland lesions.

MATERIAL AND METHODS

A total of 127 FNAC were carried out on salivary gland lesions from January 2006 to December 2010--a 5-year period. Histopathological follow-up data were obtained in 56 cases. The study was conducted to examine the sensitivity, specificity, and accuracy of FNAC for salivary gland swellings in comparison with histopathology.

RESULTS

The male-to-female ratio was 2.4:1. Parotid gland was involved in 51.1%, submandibular gland in 37%, sublingual gland in 4.7%, and minor salivary glands in 7% of patients. There were 55.9% cases of non-neoplastic lesions and 44.1% cases of neoplastic lesions on biopsy. Sensitivity, specificity, positive predictive value, and negative predictive value of FNAC for malignant neoplastic lesions were 84.61%, 86.48%, 68.75%, and 94.11%, respectively, whereas for benign neoplastic lesions, they were 84.61%, 91.66%, 91.6%, and 85%, respectively.

CONCLUSION

Fine-needle aspiration cytology is found to be a good sensitive and specific technique for the diagnosis of most of the salivary gland lesions. FNAC should be adopted as an initial investigation for all salivary gland swellings in conjunction with other investigations where appropriate.

A systematic review and meta-analysis of the diagnostic accuracy of fine-needle aspiration cytology for parotid gland lesions

The clinical usefulness of fine-needle aspiration cytology (FNAC) for the diagnosis of parotid gland lesions is controversial. Many accuracy studies have been published, but the literature has not been adequately summarized. We identified 64 studies on the diagnosis of malignancy (6,169 cases) and 7 studies on the diagnosis of neoplasia (795 cases). The diagnosis of neoplasia (area under the summary receiver operating characteristic [AUSROC] curve, 0.99; 95% confidence interval [CI], 0.97-1.00) had higher accuracy than the diagnosis of malignancy (AUSROC, 0.96; 95% CI, 0.94-0.97). Several sources of bias were identified that could affect study estimates. Studies on the diagnosis of malignancy showed significant heterogeneity (P < .001). The subgroups of American, French, and Turkish studies showed greater homogeneity, but the accuracy of these subgroups was not significantly different from that of the remaining subgroup. It is not possible to provide a general guideline on the clinical usefulness of FNAC for parotid gland lesions owing to the variability in study results. There is a need to improve the quality of reporting and to improve study designs to remove or assess the impact of bias.

Diagnostic accuracy of fine needle aspiration cytology in parotid lesions

Objective. Histopathology of parotid gland tumors is extremely varied and complex due to heterogeneous cellular composition. Preoperative diagnostic tools include fine needle aspiration cytology, the role of which remains controversial. The aim of this paper is to evaluate the usefulness and accuracy of fine needle aspiration cytology (FNAC) in the diagnosis of parotid gland tumors. Methods. We retrospectively reviewed charts of 129 patients who underwent parotidectomy for parotid lesions at Aga Khan University Hospital from 2002 to 2010. We compared the results of preoperative FNAC with final histopathological diagnosis. Results. Concordance with histological results was observed in 86%, specificity was 98%, sensitivity was 84%, and diagnostic accuracy was 94%. Conclusion. Our results demonstrate that preoperative cytology in parotid lesions is fairly accurate and useful in diagnosing benign from malignant and in planning appropriate approach for treatment.

Parotid carcinoma: Current diagnostic workup and treatment

In this review we present recent progress in diagnostic workup, prognostic evaluation, treatment options and resulting outcomes. Whenever possible, complete resection remains the mainstay of treatment. Sacrifice of facial nerve branches is reserved for the clinically or electromyographically dysfunctioning facial nerve. Clinical or radiological neck disease demands combined surgery and radiotherapy. Treatment of the N0 neck is indicated for advanced stage-high grade tumors but the question remains unanswered whether this should be surgical or radiotherapeutic elective treatment. Surgery alone will cure low stage, low grade tumors, that show no additional negative prognostic factors following adequate resection. In all other tumors postoperative radiotherapy will improve locoregional control. This approach results in good locoregional control, in a way that distant metastasis remains the typical presentation of treatment failure. In this setting, the results of systemic treatment today remain limited, but a huge effort in the molecular biology field has been done to introduce targeted therapy into this domain of head and neck cancer. Disease control remains variable within the patient population. This variation can increasingly be predicted by systems that incorporate the combined information of multivariately identified and quantified prognostic factors into an individualized prognosis for the parotid carcinoma patient.

Gland-preserving surgery for pleomorphic adenoma in the submandibular gland

BACKGROUND

Removal of tumours arising in the submandibular gland (SMG) usually involves excision of the entire gland. This prospective study evaluated the efficacy of gland-preserving surgery in patients with benign SMG tumours.

METHODS

Twenty consecutive patients with pleomorphic adenomas in the SMG underwent local excision of tumours with limited tumour-free margins and preservation of the remnant glandular tissues. All patients had salivary scintigraphy before and 6 months after surgery, with ultrasonography 2 years after operation. Complications, operating time, salivary function and rates of tumour recurrence were evaluated.

RESULTS

The mean operating time was 28 min, and no patient had neurological complications. After surgery, the function of the affected gland was equal to that of the unaffected gland. All patients had symmetrical facial contours without defects in the operated submandibular triangle. None of the patients had evidence of tumour recurrence on ultrasonographic examination and regular clinical examination at a median of 36 months after surgery.

CONCLUSION

Gland-preserving surgery in patients with benign SMG tumours preserves salivation, and reduces surgical morbidity and operating time, with good cosmesis but without compromising local control.

The value of fine-needle aspiration cytology in salivary gland lesions, 1994-2004

OBJECTIVE

Fine-needle aspiration cytology (FNAC) of the salivary gland is a commonly accepted, sensitive and specific technique in the diagnosis of both neoplastic and nonneoplastic lesions of the salivary gland. The aim of this study was to investigate the efficacy of FNAC of salivary gland lesions and to decide whether the radiologist could perform it or not.

METHODS

We aspirated 162 salivary gland lesions of 56 patients undergoing biopsy and excision. A cytopathologist and a surgical pathologist made histopathological and cytological examinations in a blinded fashion.

RESULTS

In the present study, among the FNAC performed in 162 patients with salivary gland masses, 15 (9%) were inadequate, and the remaining 147 were diagnostic. Of the 162 cases, 56 (35%) were also checked histologically. With FNAC there were 89 (55%) nonneoplastic and 58 (36%) neoplastic lesions. With FNAC 45 of the neoplastic lesions were benign and 13 malignant tumors. When cytohistopathological correlation was performed, the overall accuracy in diagnosing benign and malignant lesions was 91 and 78%, respectively, except for 2 malignant lymphoma cases. The sensitivity and specificity for benign and malignant lesions were 72 and 100%, respectively. The diagnostic sensitivity for all neoplastic and nonneoplastic lesions was 84% and the specificity 92%. There was 1 false-positive result, in which a nonneoplastic lesion was misdiagnosed as a Warthin's tumor. Fifteen (26%) cases were false-negative, 12 of which were undefined.

CONCLUSION

FNAC is a useful and reliable tool in the diagnosis of salivary gland masses when performed by a radiologist or a clinician. There are no contraindications, and complications are minimal.

Preoperative cytology in the management of parotid neoplasms

BACKGROUND

This study evaluates the diagnostic role of preoperative cytology of parotid neoplasms. The method is particularly useful in the evaluation of the parotid diseases in which the same clinical features may be treated variously. Fine-needle aspiration biopsy is a simple and well-tolerated diagnostic tool, which provides accurate information for diagnosis and follow-up of the disease. The accuracy of the method partly depends on the operator skill.

MATERIALS AND METHODS

From a series of 452 subjects who underwent parotidectomy, preoperative cytological evaluation was available in 310 and compared with histological diagnosis in a retrospective review.

RESULTS

The agreement between histotype determination using fine-needle aspiration biopsy and final histological diagnosis was 79%, specificity was 100%, sensitivity was 83%, and diagnostic accuracy was 97%.

CONCLUSION

These findings demonstrated that, given the low complication rate, preoperative cytology is particularly useful in diagnosing parotid disease and in planning the surgical strategy and approach.

Kann die präoperative Feinnadelpunktion bei Parotistumoren die definitive histologische Diagnose erschweren?

INTRODUCTION

Fine-needle aspiration cytology (FNAC) is a minimally invasive procedure that offers high specifity and acceptable sensitivity in the preoperative diagnosis of parotid tumors. FNAC provides information that can be particularly valuable in surgical planning and patient education. In some cases, it may even help prevent unnecessary surgery. After an FNA procedure, on rare occasions, morphological changes in the tumor may be observed and can make a definitive histological examination difficult or even impossible.

METHODS

Histopathological changes in parotid tumors after preoperative FNAC are described on the basis of a case report and a survey of the literature.

RESULTS

In rare cases, puncture-induced histopathological changes, such as hyalinization of the subepithelial stroma, necrosis and squamous metaplasia, so extensive that a definitive histological diagnosis is difficult, are observed. In the present case report, fine-needle aspiration of a 3 x 2 cm tumor, which had been classified as malignant on the basis of cytological findings, resulted in complete necrosis and made a definitive histological diagnosis impossible. Similar cases have been described by other authors in recent years.

DISCUSSION

In rare cases, histological changes in the tumor tissue can occur after an FNA procedure, making a definitive histological examination difficult or even impossible. When a preoperative FNAC is performed, the pathologist in charge should be advised accordingly. In addition, patients should be informed about this infrequent risk before undergoing the procedure.

Fine needle aspiration cytology in the management of a parotid mass: a two centre retrospective study

OBJECTIVES

There is a diversity of opinion regarding the role of fine needle aspiration cytology (FNAC) in the pre-operative evaluation of the parotid mass. This study further investigates the role of FNAC from the standpoint of the clinician attempting to resolve one or more clinical issues.

METHODS

A retrospective study conducted at two UK Hospitals with no overlap of cytopathologists or surgeons. Patients undergoing parotidectomy at each institution were identified from Pathology department databases. The definitive histopathological diagnosis was compared with any pre-operative FNAC diagnosis. Cytology results were classified as suggestive, non-diagnostic, sampling error, or misleading.

SETTING

The study was conducted in a District General Hospital and a University Teaching Hospital providing secondary care for each community.

RESULTS

For the University Teaching Hospital the sensitivity in distinguishing malignant from benign disease was 79% (95% CI 61-97%) with a specificity 84% (95% CI 73-95%). However, three of eight patients with a primary parotid salivary gland malignancy were reported as having benign disease on FNAC. For the participating District General Hospital the sensitivity in distinguishing malignant from benign disease was 38% (95% CI 13-63%) and specificity 95% (95% CI 73-95%).

CONCLUSIONS

Fine needle aspiration cytology does not reliably distinguish a benign from a malignant primary salivary gland neoplasm in the participating institutions. Where clinical teams use FNAC in an attempt to resolve this clinical problem, the results should be interpreted with caution and an ongoing audit of performance is required.

Diagnostic accuracy of fine-needle aspiration cytology and frozen section in primary parotid carcinoma

BACKGROUND

The low incidence and histologic heterogeneity of primary parotid carcinomas makes it difficult to evaluate the value of preoperative fine-needle aspiration cytology (FNAC) and intraoperative frozen section (FS) analysis. In the current study, the authors reviewed a single institution's experience regarding the preoperative and intraoperative diagnostic value of FNAC and FS in primary salivary gland carcinomas.

METHODS

Between January 1990 and December 2002, 108 primary parotid carcinomas were resected at the Department of Otorhinolaryngology, Head and Neck Surgery at the University of Berne, Inselspital (Berne, Switzerland). Included in the study were a total of 101 carcinomas with preoperative FNAC results in 88 tumors and/or intraoperative FS results in 45 tumors. In a retrospective study, the results of FNAC and FS were analyzed and compared with the corresponding histopathologic diagnoses.

RESULTS

The cytologic findings were true-positive for malignancy in 63 tumors (72%), false-negative in 22 tumors (25%), and nondiagnostic in 3 tumors (3%). The tumor grading was correct in 29 of 63 tumors (46%), and the exact tumor typing was correct in 27 of 63 (43%) true-positive tumors. The FS findings were true-positive for malignancy in 43 of 45 tumors (96%), the tumor grading was correct in 35 of 45 tumors (78%), and the tumor typing was correct in 32 of 45 tumors (71%). Overall, at the time of surgery, of the 101 parotid carcinomas, the tumor was known to be malignant in 83 tumors (82%), and the correct grade and the exact tumor type were known in 55 tumors (54%) and 48 tumors (48%), respectively.

CONCLUSIONS

FNAC recognized malignancy in 72% of tumors, but it could not be relied upon to provide an accurate tumor grading or typing. Therefore, FNAC alone is not prone to determine the surgical management of primary parotid carcinomas. The current analysis showed the statistically significant superiority of FS compared with FNAC regarding the diagnosis of malignancy, tumor grading, and tumor typing in primary parotid carcinomas.