The impact of FNAC in the management of salivary gland lesions: Institutional experiences leading to a risk-based classification scheme

Moving toward a systematic approach for reporting salivary gland cytopathology: cytohistological correlation with the application of the Milan system for risk stratification at a tertiary care center

INTRODUCTION

Fine-needle aspiration cytology (FNAC) of salivary glands is a well-established technique that plays a critical role in the preoperative diagnosis of lesions. Despite its clinical utility, it remains one of the most challenging areas in cytopathology. This is because there is no consensus on how to report salivary gland cytopathology, which has resulted in inconsistent terminology and confusion in communication among cytopathologists and clinicians. A risk stratification of FNA diagnostic categories has been recently proposed to be useful in reporting.

MATERIALS AND METHODS

A retrospective study of FNAC of salivary gland lesions reported from 2014 to 2017 was performed. The performance of the cytology reporting system was evaluated with histological diagnosis serving as the gold standard. The aspirates were then categorized according to the Milan system. Furthermore, the risk of malignancy was calculated for all diagnostic categories.

RESULTS

A total of 899 salivary gland aspirates were evaluated: 2.2% were nondiagnostic, 55.8% indicated nonneoplastic lesions, and 40.4% indicated neoplastic lesions. Histopathology was available for 172 cases. FNA had a sensitivity of 72.3% and a specificity of 92.6% with an overall diagnostic accuracy of 91.4% for differentiating malignant from benign tumors.

CONCLUSION

A tiered classification scheme as proposed by the Milan system may prove helpful in effectively guiding clinical management of patients with salivary gland lesions. Our experience with this system helps to pave the way for the adoption of the Milan System for Reporting Salivary Gland Cytopathology.

Risk stratification of fine-needle aspiration cytology of parotid neoplasms based on the Milan system-Experience from a tertiary center in Asia

BACKGROUND

The recently described Milan system provides a unified way of categorizing salivary gland fine-needle aspiration (FNA) cytology. We aim to use this system to stratify risk of malignancy in parotid FNAs.

METHODS

In this retrospective case series, 376 FNAs were preoperatively performed for 573 parotidectomies over 14 years.

RESULTS

Risk of malignancy on FNA is as follows: nondiagnostic 14.5%, non-neoplastic 26.7%, atypia of undetermined significance 29.3%, benign neoplasm 2.7%, neoplasm of uncertain malignant potential 19.1%, suspicious for malignancy 87.5%, and malignant 100%. The specific diagnoses of pleomorphic adenoma and Warthin tumor on FNA have high positive predictive value of 97.5% and 96.6%, respectively. Multivariate regression associates smaller size of lesion with a nondiagnostic or indeterminate result. Seniority of operator is associated with a lower likelihood of a nondiagnostic result.

CONCLUSIONS

This large Asian series validates the Milan system as a valuable tool in stratifying malignancy risk of parotid FNAs.

Application of the Milan System for Reporting Salivary Gland Cytopathology: A Retrospective 12-Year Bi-institutional Study

OBJECTIVES

Multi-institutional studies are required for the validation of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC).

METHODS

A total of 1,560 fine-needle aspirations of the salivary glands were retrieved from two institutions for a 12-year period. The diagnoses were reclassified based on the MSRSGC. Risk of malignancy (ROM) for each category was calculated based on 694 histologic follow-up cases.

RESULTS

The ROM for each category was: 18.3% for nondiagnostic, 8.9% for nonneoplastic, 37.5% for atypia of undetermined significance (AUS), 2.9% for benign neoplasm, 40.7% for salivary gland neoplasm of uncertain malignant potential (SUMP), 100% for suspicious for malignancy, and 98.3% for malignant. The sensitivity, specificity, positive predictive rate, and negative predictive rates were 89%, 99%, 98%, and 96%, respectively.

CONCLUSIONS

The results of the current study are in keeping with the MSRSGC. The indeterminate categories of AUS and SUMP showed intermediate ROMs at 37.5% and 40.7%, respectively.

A Call for Universal Acceptance of the Milan System for Reporting Salivary Gland Cytopathology

OBJECTIVES

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) established a standardized, tiered reporting system for salivary gland fine-needle aspiration (FNA) that has gained international acceptance among cytologists. Our goal was to review the key features of the MSRSGC to familiarize the surgical community with this system and its application to the FNA evaluation of salivary gland masses.

METHODS

A comprehensive review of the MSRSGC and its application in clinical practice.

RESULTS

The MSRSGC consists of six major diagnostic categories: 1) nondiagnostic, 2) non-neoplastic, 3) atypia of undetermined significance, 4) neoplasm (benign or salivary gland neoplasm of uncertain malignant potential), 5) suspicious for malignancy, and 6) malignant. Each diagnostic category is associated with an implied risk of malignancy with implications for clinical management.

CONCLUSIONS

The MSRSGC is similar to the system used for reporting thyroid FNA, which is familiar to most otolaryngologists and head and neck surgeons. As this reporting system continues to gain popularity among pathologists, widespread understanding by surgeons will be important to standardize communication and classification of salivary gland cytopathology to improve clinical care. Laryngoscope, 130:80-85, 2020.

Salivary Gland Fine Needle Aspiration and Introduction of the Milan Reporting System

Fine needle aspiration (FNA) is a well-established procedure for the diagnosis and management of salivary gland lesions despite challenges imposed by their diversity, complexity, and cytomorphologic overlap. Until recently, the reporting of salivary gland FNA specimens was inconsistent among different institutions throughout the world, leading to diagnostic confusion among pathologists and clinicians. In 2015, an international group of pathologists initiated the development of an evidence-based tiered classification system for reporting salivary gland FNA specimens designated the "Milan System for Reporting Salivary Gland Cytopathology" (MSRSGC) that culminated with the publication of the MSRSGC Atlas in February 2018. The MSRSGC consists of 6 diagnostic categories, which incorporate the morphologic heterogeneity and overlap among various non-neoplastic, benign, and malignant lesions of the salivary glands. In addition, each diagnostic category is associated with a risk of malignancy and management recommendations. The main goal of the MSRSGC is to improve communication between cytopathologists and treating clinicians, while also facilitating cytologic-histologic correlation, sharing of data from different laboratories for quality control, and research. Herein, we review the current status of salivary gland cytology and the role of MSRSGC in providing a framework for reporting salivary gland lesions.

To Obtain More With Less: Cytologic Samples With Ancillary Molecular Techniques-The Useful Role of Liquid-Based Cytology

CONTEXT

- Fine-needle aspiration cytology has been increasingly used as the first tool in the evaluation of several diseases. Although cytology has a relevant role in the discrimination between benign and malignant lesions, conventional slides cannot lead to 100% conclusive results. It was hoped that the introduction of liquid-based cytology (LBC) would improve the efficacy of cytology through standardization, quality improvement, and the possibility of carrying out ancillary techniques on the residual stored material. In recent decades, the application of genomic alterations has been studied on cytologic samples with feasible and reliable results. The molecular analysis offers a powerful aid to define the best clinical or surgical approaches and follow-up for patients. In recent years, the application of different ancillary techniques has been carried out on conventional slides even though LBC represents a useful additional and alternative method for molecular testing.

OBJECTIVE

- To demonstrate the relevance of LBC as a valid aid to overcoming the difficulties encountered in the application of ancillary techniques on conventional slides.

DATA SOURCES

- We examined and reviewed our experience with the application of ancillary techniques on LBC performed on different body sites.

CONCLUSIONS

- We emphasize that LBC achieves significant and accurate results. It represents a valid method for cytologic evaluation and it provides highly reproducible and informative molecular yields.

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.

Milan System for Reporting Salivary Gland Cytopathology: An Experience with the Implication for Risk of Malignancy

Introduction:

Fine-needle aspiration cytology (FNAC) is a well-established technique for evaluation of salivary gland lesions, but because of the heterogenicity and morphological overlap between spectrum of lesion, there are a few challenges in its wide use. Recently, “The Milan system for reporting salivary gland cytopathology” (MSRSGC) was introduced, providing guide for diagnosis and management according to the risk of malignancy (ROM) in different categories. The current study was conducted retrospectively to reclassify the salivary gland lesions from previous diagnosis and to evaluate the ROM in different categories.

Material and Methods:

Clinical data, FNAC specimen, histological, and clinical follow-up of cases were retrieved, cytological features were re-evaluated, and cases were reclassified as follows: Category 1: Non-diagnostic (ND); Category 2: Non-neoplastic (NN); Category 3: Atypia of undetermined significance (AUS); Category 4a: Neoplasm: benign (NB), Category 4b: Neoplasm: salivary gland neoplasm of uncertain malignant potential (SUMP); Category 5: suspicious of malignancy (SM); and Category 6: Malignant (M).

Result:

Total 293 cases were evaluated cytologically, and histological follow-up was available in 172 cases. The distribution of cases into different categories was as follows ND (6.1%), NN (38.2%), AUS (2.7%), NB (33.4%), SUMP (2.0%), SM (2.4%), and M (15%). Overall, ROM reported were 25%, 5%, 20%, 4.4%, 33.3%, 85.7%, and 97.5%, respectively for each category. Overall, sensitivity was 83.33%, specificity was 98.31%, positive predictive value was 95.74%, and negative predictive value was 92.80%.

Conclusion:

MSRSGC is a recently proposed six category scheme, which places salivary gland FNAC into well-defined categories that limit the possibilities of false negative and false positive cases.

Risk stratification of salivary gland cytology utilizing the Milan system of classification

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is based on risk stratification. Our study is a retrospective review of salivary gland fine needle aspiration cytology (FNAC) with the goal of determining the risk of malignancy (ROM) in each of the categories proposed by the MSRSGC.

METHODS

FNAC of salivary gland lesions with corresponding surgical resection specimens were retrieved over a 5-year period. Metastatic tumors were excluded. BothFNAC and corresponding surgical resections were reviewed blindly and classified as per criteria published by the MSRSGC. The ROM for each of the diagnostic categories was determined and compared with the ROM published by the MSRSGC.

RESULTS

The total number of entities and ROM in 199 reviewed cases were as follows: Nondiagnostic 18 (9.2%) (ROM 0%), non-neoplastic 4(2%) (ROM 0%), atypia of undetermined significance (AUS) 12(6%) (ROM 33%), benign neoplasm 118(59.2%) (ROM 0.8%), salivary gland neoplasm of uncertain malignant potential (SUMP) 22(11%) (ROM 40.9%), suspicious for malignancy 3(1.5%) (ROM 100%), malignant 22(11%) (ROM 100%).

CONCLUSION

The ROM reported in our study was mostly concordant with ROM published by the MSRSGC. This classification is helpful for the management of categories; nondiagnostic, non-neoplastic, benign neoplasm, suspicious for malignancy and malignant. The management is not standardized for the category, salivary gland neoplasm of uncertain malignant potential, as clinical information plays an important role in planning surgical procedures at an individual basis. Further studies will need to be performed using this new classification to help define appropriate management and predict ROM more accurately.

The utility of the Milan System as a risk stratification tool for salivary gland fine needle aspiration cytology specimens

OBJECTIVE

To perform a retrospective investigation of our institutional experience with salivary gland fine needle aspirations (FNA) through the framework of The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and assess the risks of neoplasm and malignancy for each diagnostic category.

METHODS

All salivary gland FNAs performed from January 2009 to December 2016 were retrospectively categorised according to the MSRSGC. When available, pre-operative cytological results were correlated with subsequent histological follow-up.

RESULTS

In total, 893 FNAs were reviewed. The specimens were retrospectively classified as nondiagnostic (ND: 13.5%), non-neoplastic (NN: 16.1%), atypia of undetermined significance (AUS: 10.8%), benign neoplasm (BN: 34.9%), salivary gland neoplasm of uncertain malignant potential (SUMP: 8.2%), suspicious for malignancy (SM: 2.7%) and malignant (M: 13.8%). Histological follow-up was available for 429 cases (48%); the majority (68.1%) were benign. The risks of neoplasm and malignancy for each category were as follows: ND: 64.5%, 16.1%; NN: 42.9%, 17.9%; AUS: 79.6%, 30.6%; BN: 100%, 2.2%; SUMP: 100%, 46.6%; SM: 94.7%, 78.9%; and M: 100%, 98.5%.

CONCLUSIONS

The MSRSGC is a useful classification scheme for stratifying salivary gland lesions according to their associated risk of malignancy and guiding clinicians toward appropriate management. Diagnostic pitfalls are seen in a small proportion of cases and a multidisciplinary approach for assessing salivary gland pathology is essential in their evaluation.

A critical appraisal of the Milan system for reporting salivary gland cytology (MSRSGC) with histological correlation over a 3-year period: Indian scenario

BACKGROUND

Fine needle aspiration cytology (FNAC) is the first line investigation for pre-operative diagnosis of salivary gland lesions, but due to its inherent limitations remains a challenge for the cytopathologists. The recently proposed international risk stratification scheme, the Milan System for Reporting Salivary Gland Cytology (MSRSGC) aims to promote and standardise the communication between cytopathologist and clinician thereby improving patient care.

METHODS

A retrospective study of all salivary gland cytology cases was performed over a 3-year period, reviewed by pathologists and categorised into 1 of the 6 diagnostic categories according to MSRSGC, namely, non-diagnostic, non-neoplastic, atypia of undetermined significance (AUS), benign neoplasm, and salivary gland neoplasm of undetermined significance (SUMP), suspicious for malignancy (SFM), and malignant neoplasm. Cyto- histological correlation was done wherever possible. Risk of malignancy (ROM) was calculated for each diagnostic category.

RESULTS

Out of a total of 150 salivary FNAC cases, histopathology was available for 64 cases. The sensitivity of FNAC was 81.8%, specificity was 100% while the diagnostic accuracy was 96.9%. The positive and negative predictive values were 100% and 96.4% respectively. The ROM for non-diagnostic, non-neoplastic, AUS, benign neoplasm, SUMP, SFM, and malignant categories were 0%, 10%, 50%, 2.5%, 50%, 100%, and 100% respectively.

CONCLUSION

MSRSGC fulfils the critical need for a uniform, internationally acceptable reporting system with ROM specified for each category. However, large scale multi centre studies need to be conducted before its reliability and validity is proven.

Treatment outcomes in metastatic and localized high-grade salivary gland cancer: high chance of cure with surgery and post-operative radiation in T1-2 N0 high-grade salivary gland cancer

BACKGROUND

High-grade salivary gland cancer is a distinct clinical entity that has aggressive disease progression and early systemic spread. However, because of the rarity of the disease, the clinical outcomes, prognostic factors and clinical decision on the optimal treatments have not been fully understood.

METHODS

In this study, we retrospectively analyzed the clinical data of 124 patients with high-grade salivary gland cancers and performed multivariate survival analyses to evaluate the clinico-pathological factors affecting the treatment outcomes.

RESULTS

The 5-year disease-specific survival was 63.4% in patients with high-grade salivary gland cancers. Among the clinico-pathological factors, presence of lymph node metastasis (hazard ratio 5.63, 95% confidence interval 2.64-12.03, P < 0.001) and distant metastasis (hazard ratio 4.59, 95% confidence interval 2.10-10.04, P < 0.001) at diagnosis were the most potent unfavorable prognostic factors. Importantly, patients with early-stage disease (T1-2N0M0) showed apparently a relatively excellent prognosis (93.2% 5-year disease-specific survival); meanwhile N (+) and M1 status at diagnosis resulted in dismal outcomes (44.6 and 21.1% 5-year disease-specific survival, respectively). On comparing surgery alone as a treatment modality, surgery plus postoperative radiation significantly benefited the patients, but the difference between adjuvant radiation and chemoradiation was not found to be significant. Pathological subtypes of high-grade salivary gland cancers were not significantly associated with prognosis.

CONCLUSIONS

Despite of an overall unfavorable prognosis in high-grade salivary gland cancer, patients with early-stage disease are expected to have excellent prognosis (over 90% survival rates) with surgery plus adjuvant radiation, which may implicate the patients' consultation, therapeutic decision making, and the need for early detection of the disease.

Impact on clinical follow-up of the Milan System for salivary gland cytology: A comparison with a traditional diagnostic classification

INTRODUCTION

No universally accepted classification exists for salivary gland FNA. The proposed Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) offers a uniform classification with management recommendations. We compared FNA diagnoses from a prior study with specific diagnoses with corresponding MSRSGC diagnoses.

METHODS

One-hundred and sixty-four cases from a prior cytological study with histological follow-up were re-reviewed by one of the authors and assigned to one of the MSRSGC categories. The original and MSRSCG diagnoses were compared, as were follow-up recommendations.

RESULTS

The MSRSGC system classified 29 specimens as non-diagnostic (seven histologically shown to be benign salivary gland, two non-mucinous cysts, 14 sialadenitis, one pleomorphic adenoma, one haemangioma, one lymphoma, one adenoid cystic carcinoma, one squamous carcinoma and one benign lymphoid proliferation). The original study diagnosed these lesions as: seven benign cysts, 15 benign salivary gland tissue, one benign neoplasm and two insufficient for diagnosis. In seven cases, MSRSGC disagreed with original diagnoses and surgical resection showed lesions where optimal follow-up was more consistent with original cytological diagnosis. In 10 cases with disagreement, the MSRSGC was associated with a more appropriate follow-up based on the surgical diagnosis. Malignancy risks for the Milan categories were: non-diagnostic (12%), non-neoplastic (5%), atypia of undetermined significance (19%), neoplasm, benign (5%), neoplasm (40%), suspicious for malignancy (60%) and malignant (93%).

CONCLUSION

MSRSGC was comparable with the original reported diagnoses in the majority of cases. Both systems had high accuracy for distinguishing benign from malignant lesions and both were associated with appropriate follow-up in most cases.

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC): An ASC-IAC-Sponsored System for Reporting Salivary Gland Fine-Needle Aspiration

The diagnostic role of salivary gland fine-needle aspiration (SG-FNA) is well established in the preoperative evaluation of patients with salivary gland lesions. At present, most salivary SG-FNA specimens are diagnosed based on conventional diagnostic criteria. However, there exists a lack of uniform reporting for these specimens to guide the clinical management of patients. This void motivated a group of experienced cytopathologists to spearhead the development of a uniform reporting system. This international panel, under the sponsorship of the American Society of Cytopathology (ASC) and the International Academy of Cytology (IAC), gathered in September 2015 at the European Congress of Cytology, held in Milan, Italy, to propose the “Milan System for Reporting Salivary Gland Cytopathology” (MSRSGC). This effort sparked the interest of many and brought forth an agreement to develop an evidence-based tiered classification consisting of 6 diagnostic categories. It is hoped that this standard reporting system will enhance the overall effectiveness of SG-FNA reporting across institutions, with the ultimate result being better communication and improved patient care.

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC): an ASC-IAC-sponsored system for reporting salivary gland fine-needle aspiration

The diagnostic role of salivary gland fine-needle aspiration (SG-FNA) is well established in the preoperative evaluation of patients with salivary gland lesions. At present, most salivary SG-FNA specimens are diagnosed based on conventional diagnostic criteria. Nevertheless, there exists a lack of uniform reporting for these specimens to guide the clinical management of patients. This void motivated a group of experienced cytopathologists to spearhead the development of a uniform reporting system. This international panel, under the sponsorship of the American Society of Cytopathology (ASC) and the International Academy of Cytology (IAC), gathered in September 2015 at the European Congress of Cytology, held in Milan, Italy, to propose "The Milan System for Reporting Salivary Gland Cytopathology. This effort sparked the interest of many and brought forth an agreement to develop an evidence-based tiered classification consisting of 6 diagnostic categories. We hope that this standard reporting system will enhance the overall effectiveness of SG-FNA reporting across institutions, with the ultimate result being better communication and improved patient care.

Northern Italy in the American South: Assessing interobserver reliability within the Milan System for Reporting Salivary Gland Cytopathology

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has been proposed to standardize salivary gland fine-needle aspiration (FNA) diagnoses. This study assessed salivary gland FNA results and risk of malignancy (ROM) rates at the University of North Carolina as well as the interobserver reliability (IOR) of the atypia of undetermined significance (AUS) and salivary gland neoplasm of uncertain malignant potential (SUMP) categories.

METHODS

The electronic medical record was searched for FNA cases from 2010 to 2017 with subsequent surgical resections. Histologic diagnosis was used for gold-standard comparison. The original cytologic results were then converted into MSRSGC categories (nondiagnostic, nonneoplastic, AUS, benign neoplasm, SUMP, suspicious, and malignant). For the assessment of IOR, 23 cases were selected with enrichment for cases diagnosed as AUS (n = 11) or SUMP (n = 9). Six boarded cytopathologists and 1 cytopathology fellow assessed representative slides and provided an MSRSGC diagnosis for each case. Fleiss' κ coefficients were calculated to determine IOR.

RESULTS

The ROM was 33% for both AUS and SUMP cases; however, the risk of neoplasia was 56% for AUS cases and 100% for SUMP cases. Fleiss' κ for the AUS category was 0.217 (P < .05), and Fleiss' κ for the SUMP category was 0.024 (P = .74).

CONCLUSIONS

In this study assessing the IOR of MSRSGC categories, fair agreement and slight agreement were found for the AUS and SUMP categories, respectively. Observers preferentially used the AUS or benign neoplasm category for SUMP cases, perhaps because of unfamiliarity with SUMP as a diagnostic option. The initial adoption of a new reporting system will require a quality assessment to ensure that the system is reliable and useful for clinicians. Cancer Cytopathol 2018;126:390-6. © 2018 American Cancer Society.

Pleomorphic Adenoma Originating from Heterotopic Salivary Tissue of the Upper Neck: A Diagnostic Pitfall

Pleomorphic adenoma directly arising in the neck is thought to originate from heterotopic salivary gland tissue. In this article, we present the case of a 55-year-old female patient with a histologically proven pleomorphic adenoma located at the left mandibular angle, anteriorly to the sternocleidomastoid muscle and posteroinferiorly to the submandibular gland. As the patient also had an ipsilateral thyroid nodule with coarse calcifications, clinical and radiological features suggested a possible level II metastatic lymph node. However, ultrasound-guided fine needle aspiration cytology and postsurgery histopathological examination revealed a pleomorphic adenoma arising from heterotopic salivary gland tissue unrelated to a benign thyroid nodule. In this article, we provide a review of the existing literature on heterotopic salivary gland tissue and related neoplasms and discuss their imaging presentation.

[Cyto-histological correlation in the management of parotid gland tumors: A retrospective study of 160 cases]

INTRODUCTION

The aim of this study was to correlate the cytological and histological results and evaluate the diagnostic performance of fine-needle aspiration cytology (FNAC) in the management of parotid gland tumors.

METHODS

This retrospective study included 160 patients with a parotid gland tumor who underwent fine-needle aspiration and parotidectomy surgery between January 2005 and August 2016 at the Limoges university hospital center.

RESULTS

On 160 fine-needle aspirations performed, fine-needle aspiration diagnoses were: 77 benign lesions, 35 malignant lesions and 48 non-diagnostic cases. Final histological diagnosis revealed there were 113 benign lesions and 47 malignant lesions. A hundred and one cytological diagnoses were accurate over 112 contributive fine-needle aspirations: seven false-negative cases and 4 false-positive cases were observed. The sensitivity, specificity, and accuracy were 82, 95 and 90% respectively for fine-needle aspiration, and 83, 95 and 92% respectively for association of fine-needle aspiration and magnetic resonance imaging. Diagnostic concordance between fine-needle aspiration and final histology for malignant lesions was 78%. A greater number of contributive fine-needle aspirations was observed among experimented operators.

DISCUSSION

Fine-needle aspiration is a reliable, safe and effective diagnostic tool that allows good differentiation between malignant and benign diagnosis in the preoperative management of parotid gland tumors. The association of fine-needle aspiration and magnetic resonance imaging (MRI) can improve diagnostic performance.

A pattern-based risk-stratification scheme for salivary gland cytology: A multi-institutional, interobserver variability study to determine applicability

BACKGROUND

Salivary gland aspiration cytology is useful in the preoperative management of patients but remains challenging, because of the extensive morphologic overlap of some tumors limits the ability to always determine the presence of malignancy. In response to this challenge, there has been increasing drive to develop a risk-based categorization scheme for salivary gland aspirates. Herein, the authors examine the interobserver variability of 1 such pattern and risk-based system.

METHODS

Select smears and cell-block sections of 50 salivary gland aspirates from 2 large academic centers were digitally imaged. These scanned slides were independently and blindly reviewed by 4 cytopathologists, and each aspirate was assigned to 1 of the proposed pattern-based categories if it was considered neoplastic by the observer. Interobserver agreement was scored and aggregated risks of malignancy were calculated for cases with available surgical follow-up.

RESULTS

In total, 42 samples (84%) were considered neoplastic by at least 2 observers and were scored for interobserver agreement: 10 of 42 (23.8%) had uniform agreement, 14 of 42 (33.3%) had majority agreement, and 5 of 42 (11.9%) had divided agreement. Only 9 of 42 samples (21.4%) had minimal agreement, and 4 of 42 (9.5%) had no agreement. Condensation of similar categories was able to improve interobserver agreement and still maintain stratified risk of malignancy.

CONCLUSIONS

The proposed pattern-based risk-stratification scheme, which could be implemented with the forthcoming Milan System, has good overall interobserver agreement and successfully stratifies the risk of malignancy. Some simplification is possible to make the system easier to use and improve interobserver agreement while maintaining stratification of risk. Cancer Cytopathol 2017;125:776-85. © 2017 American Cancer Society.

Three-year cytohistological correlation of salivary gland FNA cytology at a tertiary center with the application of the Milan system for risk stratification

BACKGROUND

Fine-needle aspiration (FNA) cytology of salivary glands is a well-established technique that plays a critical role in the preoperative diagnosis of lesions. A risk stratification of FNA diagnostic categories has been recently proposed to be useful in reporting. The aims of this study were to evaluate the diagnostic accuracy of salivary gland FNA and to apply the proposed Milan system for reporting salivary gland lesions.

METHODS

A retrospective audit of FNA specimens of salivary gland lesions reported from 2014 to 2016 was performed. A correlation with the follow-up histopathology, wherever it was available, was performed. The aspirates were then categorized according to the Milan system as follows: nondiagnostic, nonneoplastic, atypical, benign neoplasm, neoplasm of uncertain malignant potential (NUMP), suspicious for malignancy, or positive for malignancy. Furthermore, the risk of malignancy and the risk of high-grade malignancy were calculated for all diagnostic categories.

RESULTS

A total of 631 salivary gland aspirates were evaluated: 2.2% were nondiagnostic, 55.8% indicated nonneoplastic lesions, and 40.4% indicated neoplastic lesions. Histopathology was available for 94 cases (14.9%). FNA had a sensitivity of 79.4% and a specificity of 98.3% with an overall diagnostic accuracy of 91.4% for differentiating malignant tumors from benign tumors. The overall risk of malignancy was 17.4% for the nonneoplastic category, 100% for the atypical category, 7.3% for the benign neoplasm category, 50% for the NUMP category, and 96% for the positive-for-malignancy category.

CONCLUSIONS

Salivary gland FNA continues to have high diagnostic accuracy and is thus helpful for guiding management. Neoplasms with classic cytomorphology are easily diagnosed; however, in difficult cases showing overlapping features, the use of the Milan system could be beneficial. Cancer Cytopathol 2017;125:767-75. © 2017 American Cancer Society.

The Milan System for Reporting Salivary Gland Cytopathology: Analysis and suggestions of initial survey

BACKGROUND

An international panel of experts in the field of salivary gland cytology (SGC), supported by the American Society of Cytopathology (ASC) and the International Academy of Cytology, conducted a survey to seek evidence and practice patterns regarding SGC. Results were used to provide focus for the proposed Milan System for Reporting Salivary Gland Cytopathology.

METHODS

The study group, formed during the 2015 European Congress of Cytology held in Milan, Italy, generated a survey that included 49 specific questions related to the taxonomies, practices, and diagnostic entities of salivary cytology. Qualtrics software was used as the study platform. Software and server support were provided by the division of information technology at the University of Wisconsin. The survey was available online from November 2015 until February 2016. Participants were invited through the Web sites of the ASC, the International Academy of Cytology, and the Papanicolaou Society of Cytopathology as well as by the ASC e-mail "ListServe"; responses were evaluated by the Milan System editors.

RESULTS

Responses from a total of 515 participants were collected and reviewed. A total of 347 participants provided demographic data information. Responses revealed variations in diagnostic practice and subsequent management. Participants believed that the acceptable rate for nondiagnostic samples should not be higher than 10%. There were varied opinions regarding the approach to neoplastic lesions of uncertain malignant potential, those that may or may have not local invasion and distant spread.

CONCLUSIONS

Results of the survey demonstrated strong support for the development of a unified system for reporting SGC. Cancer Cytopathol 2017;125:757-66. © 2017 American Cancer Society.

Cystic major salivary gland lesions: Utilizing fine needle aspiration to optimize the clinical management of a broad and diverse differential diagnosis

INTRODUCTION

The use of fine-needle aspiration (FNA) cytology for the preoperative evaluation of salivary gland lesions is an accepted but, currently, nonstandardized practice. More specifically, cystic major salivary gland lesions are relatively rare and can be very challenging to diagnose on FNA due to low cellularity and an incredibly broad differential diagnosis. The purpose of this study was to investigate the diagnostic utility of preoperative FNA cytology for cystic major salivary gland lesions.

METHODS AND MATERIALS

The electronic pathology archives of The Johns Hopkins Hospital were searched to identify FNA specimens of cystic major salivary gland lesions over a 15 year period (January 1, 2000 to December 21, 2015). The age, race, sex, biopsy site, use of ultrasound guidance, cytopathologic diagnosis, and presence or absence of clinical follow-up were recorded for each patient. Cases were divided into those with and without follow-up. Diagnostic performance between FNA and follow-up data were recorded.

RESULTS

A total of 145 cases met the inclusion criteria, while 123 (84.8%) patients had follow-up data available. Of these patients, 67.5% underwent FNA as the only pathologic diagnostic modality. Sensitivity, specificity, positive predictive value, and negative predictive value for the detection of cystic neoplasms were 41.6%, 99.0%, 90.9%, and 87.6%, respectively. For cases containing mucin, 100.0% sensitivity and specificity were achieved.

CONCLUSION

FNA of cystic salivary gland lesions is a useful clinical decision-making tool that can reduce the number of patients ultimately requiring surgical excision. Although specificity is high, a relatively low overall sensitivity makes clinical and radiologic correlation imperative.

Use of fluorescent in-situ hybridisation in salivary gland cytology: A powerful diagnostic tool

OBJECTIVE

Salivary gland cytology is challenging because it includes a diversity of lesions and a wide spectra of tumours. Recently, it has been reported that many types of salivary gland tumours have specific molecular diagnostic signatures that could be identified by fluorescent in-situ hybridisation (FISH). The aim of the present study was to demonstrate the feasibility and efficiency of FISH on routine cytological salivary gland smears.

METHODS

FISH was conducted on 37 cytological salivary gland smears from 34 patients. According to the cytological diagnosis suspected, MECT1/MAML2 gene fusion and rearrangements of PLAG1, MYB, or ETV6 were analysed. The presence and percentages of cells that had gene rearrangements were evaluated. Results were compared with the histological surgical samples, available from 26 patients.

RESULTS

The PLAG1 rearrangement was observed in 12/20 (60%) cases of pleomorphic adenoma. MECT1/MAML2 gene fusion was observed in 1:2 mucoepidermoid carcinomas but was not observed in five other tumours (two pleomorphic adenomas, one Warthin's tumour, one mammary analogue secretory carcinoma [MASC] and one cystic tumour). MYB rearrangement was observed in 4/4 adenoid cystic carcinomas. ETV6-gene splitting identified one MASC.

CONCLUSION

Overall, FISH had a specificity of 100% and a sensitivity of 66.7%. When FISH and cytological analyses were combined, the overall sensitivity was increased to 93.3%. It can thus be concluded that when the FISH analysis is positive, the extent of surgery could be determined with confidence pre-operatively without needing a diagnosis from a frozen section.