Diagnostic Approach to Fine Needle Aspirations of Cystic Lesions of the Salivary Gland

Clinical Decision-Making and Risk of Malignancy when Parotid Gland Fine Needle Aspiration Cytology Indicates a Non-Neoplastic or Non-Diagnostic Finding

INTRODUCTION

Non-neoplastic and non-diagnostic cytological findings present a diagnostic and therapeutic challenge in head and neck oncology. Both groups still harbor a risk of malignancy (ROM). Of note, ROM values have been counted from surgically confirmed lesions only. The purpose of this study was to evaluate the clinical course of patients with non-neoplastic or non-diagnostic fine needle aspiration cytology (FNAC) findings from a parotid gland lesion.

METHODS

This retrospective cohort study comprises all 184 consecutive patients who visited the Department of Otorhinolaryngology - Head and Neck Surgery, Helsinki University Hospital (HUS, Helsinki, Finland) and whose first parotid gland FNAC result during 2016-2018 was non-neoplastic or non-diagnostic. The cytology reports were obtained from the HUS Pathological Archives (Q-Pati). Demographics, physical examination findings, and cytopathological and treatment data were reviewed. Two patient groups were formed according to their clinical management: those who had surgery and those who were only followed up. If the parotid gland was operated on, FNAC was compared with histology. If the patient was followed up without surgical treatment, the follow-up data included a review of the patient records supplemented with a questionnaire.

RESULTS

Altogether, there were 186 parotid lesions. Seventy-six (40.9%) tumors in 75 patients were operated on, and 110 (59.1%) were only followed up. Of all parotid gland lesions, 12 (6.5%) turned out to be malignant, and all of them were in the surgically treated group. When only followed up clinically, with repeated needle sampling or imaging during the minimum 4-year follow-up period, none of the other lesions turned out to be malignant.

CONCLUSION

The ROM for non-diagnostic and non-neoplastic FNAC samples is lower when all FNAC samples, including also those from nonsurgically treated patients, are included in comparison with the series that includes only surgically treated patients with histopathological confirmation. Our results suggest that this patient group can be followed up conservatively in the absence of abnormal symptoms or radiological findings.

Polymorphous Adenocarcinoma of the Parotid Gland: A Rare Entity in Asians With a Unique Cystic Presentation

Polymorphous adenocarcinoma (PAC) of the parotid is a rare entity with minimal reported incidences in the Asian population. It generally presents as a solid tumor and is considered a diagnostic dilemma due to morphological diversity and variable histological patterns. This article reports a unique fluid-filled PAC of the parotid gland mimicking a cystic lesion in an Indian male, with a review of relevant literature. A 64-year-old male patient presented with a slow-growing swelling of the left parotid region for the last 10 years. The cytology report suggested a cystic swelling. The patient underwent superficial parotidectomy. A detailed histopathological examination confirmed it as a classical variant of PAC. He remains disease-free over 24 months post-surgery follow-up.

Imaging Spectrum of Extrathyroidal Neck Masses

ABSTRACT

Extrathyroidal masses in the anterolateral neck are frequently encountered in the adult population and may represent a diagnostic dilemma. These neck masses can result from a diverse array of pathologies including congenital, inflammatory, infectious, and neoplastic causes. Relevant medical history and physical examination are essential to complement the imaging findings. Ultrasound (US) plays an important role in the initial evaluation of neck masses due to its reliability, availability, safety and cost-effectiveness. It can confirm or exclude the presence of a mass and initially characterize it as solid or cystic. Sonographically assessing the relationship of a mass to adjacent cervical anatomy can facilitate a more targeted differential diagnosis. US also effectively guides fine needle aspirations and/or biopsies of accessible lesions. Multimodality imaging is reserved for problem-solving complex cases and presurgical planning. The anterolateral neck masses are categorized into midline/paramedian lesions, salivary gland pathologies, and other soft tissue lesions. Midline and paramedian lesions include thyroglossal duct pathologies, ectopic thyroid tissue, and parathyroid adenomas. Salivary gland pathologies include obstructive/inflammatory processes, benign and malignant neoplasms, and systemic diseases. This pictorial essay presents clinical features and sonographic characteristics of extrathyroidal masses in the anterolateral neck with a brief discussion of other imaging modalities.

Interventional cytopathologist perspective on the Milan System Classification: a study on 929 consecutive salivary gland fine-needle aspirations with a focus on challenging diagnostic categories

Background

Although the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has improved the diagnosis and management of salivary gland lesions, determining the risk of malignancy (ROM) for AUS and SUMP categories remains challenging. We investigated the role of interventional cytopathologists in refining the differential diagnosis of these categories.

Methods

We searched for salivary gland fine-needle aspirations (FNAs) performed at our Institution since the publication of the first edition of MSRSGC. In our Institution, salivary gland FNAs are performed by interventional cytopathologists only. We checked for the availability of histopathology reports to calculate the risk of neoplasm (RON) and ROM. Sensitivity, specificity, negative predictive value, and positive predictive values of our FNAs were assessed by focusing on the contribution of the AUS and SUMP categories to our diagnostic accuracy.

Results

929 salivary gland FNA diagnoses were retrieved. 37.02% FNAs had an available surgical follow-up. The ROM for each category was: 6% (ND); 0 (NN); 15.15% (AUS); 1.14% (NB); 24.4% (SUMP); 66.7% (SFM); and 94.74% (M). We observed a high level of concordance between our ROM data and the values proposed by the MSRSGC; higher accuracy (93.17%) and sensitivity (97%) were obtained when the AUS category was considered as a positive index for detecting salivary neoplasms; the best diagnostic accuracy (93.33%) was obtained when the SUMP category was considered as a negative index for malignancy.

Conclusion

Interventional cytopathologists play an important role in salivary gland cytopathology, as demonstrated by the overt concordance between our ROM rates and those recommended by the MSRSGC.

Cytological features of a lymphoepithelial cyst of the salivary gland with application of the second edition of Milan System for Reporting Salivary Gland Cytopathology

Lymphoepithelial cysts (LECs) of the salivary glands are relatively rare, benign cystic lesions. Characteristic histopathological features of LEC include presence of well-circumscribed unilocular cysts surrounded by dense lymphoid tissue with lymphoid follicles. These cysts are lined by a combination of squamous, ciliated, columnar and mucous epithelia. Fine-needle aspiration (FNA) cytology is the standard preoperative diagnostic procedure for salivary gland lesions. Although the cytological diagnosis of cystic salivary gland lesions is difficult, the use of Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) in the cytodiagnosis of cystic salivary gland lesions has been reported. However, only a few studies have described the cytological features of LEC. To the best of our knowledge, the present study reviewed the cytological features of a case series of LEC and evaluated the application of MSRSGC for the first time. This retrospective study included 13 patients with LEC of the salivary glands who underwent pre-operative FNA followed by surgical resection of the cyst. All the lesions were present in the parotid gland. Cytological analysis revealed no epithelial cell component in eight patients (62.5%) along with a proteinaceous background containing lymphocytes and/or foamy cells. Non-keratinising squamous epithelium was observed in three patients. Amylase crystalloids were noted in two patients. None of the patients were cytodiagnosed with LEC. Eight, three, one and one patients were categorised as MSRSGC I, II, III, and IVa, respectively. The results of the present study demonstrated that cytodiagnosis of LEC was difficult due to the absence of epithelial component in 62.5% of the specimens. However, evaluation of its benignity was not difficult. Thus, it can be summarized that MSRSGC may be useful for cytological evaluation of LECs.

An Uncommon Salivary Gland Swelling- Parotid Duct Cyst and Its Management

Cysts in the parotid region are more common in the gland than in the duct. Isolated cyst of parotid duct is a rare presentation. The treatment for most of the cystic lesions of the parotid or the parotid duct is the excision of the cyst with superficial parotidectomy. However, these lesions can be approached intra-orally for marsupialization achieving the same surgical results with less morbidity. This paper presents a rare case of parotid duct cyst which was managed by intraoral drainage and marsupialization. A 53-year-old female presented with swelling in the right cheek, associated with frequent fluid drainage inside the oral cavity for four months. Radiology and Fine needle aspiration revealed a benign parotid duct cyst with normal parotid gland. It was managed by a simple surgical technique of marsupialization. The patient was followed up for 1 year with no evidence of recurrence. Marsupialization obviates the need for parotidectomy in the simple cystic lesion of the parotid duct, unlike the cystic lesion in the gland per se and also reduces risk of recurrence. The simplicity and lack of major complications make it an effective treatment for salivary duct cysts.

Cystic lesions in the salivary gland. Pitfalls to be avoided on cytology

Cystic lesions of the salivary glands are very uncommon entities. However, on occasion, some neoplasms of the salivary glands show a cystic component, which may be predominant or only partially cystic. Basal cell adenoma, canalicular adenoma, oncocytoma, sebaceous adenoma, intraductal papilloma, epithelial-myoepithelial carcinoma, intraductal carcinoma, and secretory carcinoma are such cystic entities. Cystic degeneration and necrosis, which can develop within solid tumours, represent another possibility. The ability to recognise this type of lesion is a challenge in diagnostic cytology because hypocellular fluid is frequently recovered. Furthermore, evaluating all of the differential diagnoses for cystic lesions of the salivary glands is helpful in obtaining the correct diagnosis. Herein, we evaluate the various types of cystic lesions within the salivary glands.

Benign Lymphoepithelial Cyst of Parotid Gland: A Pathologist's Perspective

Benign lymphoepithelial cyst (BLEC) of the salivary gland is a gradually increasing cystic lesion commonly associated with human immunodeficiency virus (HIV) infection. In rare instances, it can be seen in immunocompetent patients. Here, such a classic case of BLEC of the parotid gland in an elderly seronegative patient has been reported. Proper medical history, physical examination, radiology, and fine needle aspiration can fetch a preoperative diagnosis. However, histopathology helps to rule out other possibilities. Surgical excision is the best treatment modality with lower chances of recurrences.

Top Ten Oncocytic Head and Neck Lesions to Contemplate

BACKGROUND

Oncocytes are a component of many metaplastic and neoplastic lesions throughout the head and neck area, primarily originating in salivary/seromucinous glands and the thyroid gland. In addition, other lesions can contain cells that mimic oncocytes (pseudo-oncocytes); these can be of epithelial or non-epithelial origin.

METHODS

Review article.

RESULTS

Oncocytic metaplasia is common in seromucinous glands throughout the upper aerodigestive tract, most notable in the oral cavity, nasopharynx and larynx. The main oncocytic salivary gland neoplasms are Warthin tumor and oncocytoma. Infarction of Warthin tumor may lead to recognition difficulties. Oncocytic subtypes of mucoepidermoid carcinoma and intraductal carcinoma have morphologic and immunohistochemical features that allow distinction from major oncocytic entities. Oncocytic thyroid tumors include adenoma, carcinoma (follicular, papillary and medullary), along with poorly differentiated tumors. Oncocytic papillary sinonasal and middle ear tumors must be distinguished from low grade adenocarcinomas. Pseudo-oncocytic entities include paraganglioma, Langerhans cell histiocytosis, giant cell tumor, rhabdomyoma, and metastatic tumors.

CONCLUSIONS

Correct diagnosis of oncocytic head and neck lesions requires a knowledge of the spectrum of possible entities, their characteristic sites of occurrence, architecture, histomorphology, and immunohistochemistry. Oncocytic subtypes of several newly described entities are now recognized. Both epithelial and non-epithelial mimics of oncocytes exist. The molecular features of oncocytic tumors can be helpful in their diagnosis and understanding their pathogenesis.

DIFFERENTIAL-DIAGNOSTIC INFORMATIVENESS OF THE MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL STUDY OF PAROTID SALIVARY GLAND CYSTS

OBJECTIVE

The aim: To conduct a general analysis of the results of the study of the morphological and immunohistochemical structure of cysts of the parotid salivary glands.

PATIENTS AND METHODS

Materials and methods: Our study is based on the application of generally accepted, additional and special methods of examination, which concerns 21 patients who underwent surgical intervention to remove cystic formations of the parotid salivary gland.

RESULTS

Results: It was established that there are 2-3 HLA-DR+ cells per 100 epithelial cells located in the basal and subbasal layers in the form of their continuous ribbon and their moderate infiltration of tissues within the acinar epithelium. In the epithelium, CD3+ cells were also detected in the number of 1 to 7 per 100 epitheliocytes and they were the most numerous, along with HLA-DR+ cells. Instead, the presence of CD4+ and CD20+ cells was not detected in the epithelium, unlike the subepithelial layer, where they occupied significant areas. In turn, the infiltration of CD8+ cells of the epithelial layer was established in the amount from 1 to 7 per 100 epitheliocytes. A moderate number of them was also determined subepithelially, and they were single directly in the cyst wall.

CONCLUSION

Conclusions: Immunohistochemical study of the structural components of cystic formations is this is the direct way to establish the nature of the redistribution of immune cells in it, which is very important when conducting differential diagnosis in difficult and doubtful cases.

Cystic Salivary Gland Neoplasms: Diagnostic Approach With a Focus on Ancillary Studies

Cystic salivary gland cytology can be challenging due to the fact that a cystic mass can be the clinical presentation of both non-neoplastic and neoplastic conditions. Neoplastic lesions consist of both benign and malignant neoplasms. The cytomorphologic features of these entities can overlap and the cystic background may additionally contribute to the complexity of these lesions and their interpretation. Ancillary studies have been reported in several studies to be beneficial in further characterization of the cellular components and subsequent diagnosis of the cystic lesions of the salivary gland. Fluorescence in situ hybridization, real-time polymerase chain reaction, and next-generation sequencing are now being utilized to detect molecular alterations in salivary gland neoplasms. MALM2 rearrangement is the most common gene fusion in mucoepidermoid carcinoma. PLAG1 rearrangement is present in more than half of pleomorphic adenomas. AKT1:E17K mutation is the key diagnostic feature of the mucinous adenocarcinoma. NR4A3 overexpression is highly sensitive and specific for the diagnosis of acinic cell carcinoma. MYB fusion is noted in adenoid cystic carcinoma. ETV6:NTRK3 fusion is helpful in diagnosis of secretory carcinoma. p16 and human papillomavirus (HPV) studies differentiate HPV-related squamous cell carcinoma from non-HPV-related neoplasms with overlapping features. NCOA4:RET fusion protein is the main fusion in intraductal carcinoma.

The Milan System for Reporting Salivary Gland Cytopathology

OBJECTIVES

Our study assesses whether the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) offers any benefit over the original cytology classification, and measures interobserver agreement.

METHODS

Four cytopathologists retrospectively blindly classified preoperative cytology by MSRSGC from 101 resected salivary tumors. Consensus MSRSGC diagnoses were correlated with surgical pathology diagnoses and compared with the original cytology classification. Diagnostic parameters were calculated for both systems. Interobserver variability was assessed.

RESULTS

The original cytology classification vs MSRSGC had sensitivity, specificity, positive predictive value, and negative predictive value of 75.0% vs 78.3%, 97.1% vs 98.0%, 91.2% vs 94.7%, and 90.1% vs 90.0%, respectively. The original cytology classification risk of neoplasm (RON) was 91.7% for "negative for malignancy" and 100.0% for other categories. The MSRSGC RON was 71.4% in category II (nonneoplastic) and 100.0% in all other categories. The original cytology classification risk of malignancy (ROM) ranged from 0.0% for "atypical" to 100.0% for "positive for malignancy." The MSRSGC ROM ranged from 0.0% in categories I (nondiagnostic) and III (nonneoplastic) to 100.0% in category VI (malignant). Weighted agreement using the MSRSGC was 92% (Gwet AC1, 0.84); unweighted agreement was 69% (Gwet AC1, 0.64). MSRSGC category IVA (benign neoplasm) was most likely to show interobserver agreement, with complete agreement in 67% of cases.

CONCLUSIONS

The MSRSGC performs similarly to the original cytology classification and shows relatively high interobserver agreement.

Mucoepidermoid carcinoma: Analysis of 76 cytologic cases and correlation with histologic grade

BACKGROUND

Mucoepidermoid carcinoma (MEC) is the most common salivary gland (SG) malignancy. In this study, the author undertook analysis of a large collection of MEC cytologic cases.

MATERIALS AND METHODS

Cytopathology files were searched for MEC cases with histopathologic confirmation. Fine-needle aspiration (FNA) smears used standard technique.

RESULTS

Seventy-six cases (63 patients [M:F = 1:1; age range, 23-87 years; mean age, 58 years]) met inclusion criteria. Aspirates were primary (54 [71%]), metastatic (18 [24%]), and locally recurrent (4 [5%]). FNA sites included parotid gland (49 [64%]), regional lymph nodes (11 [14%]), submandibular gland (5 [7%]), inner canthus of eye (2 [3%]), and lung (2 [3%]); and single specimens from palate, jaw, shoulder, paranasal sinus, floor of mouth, ear canal, and effusion. Cytologic diagnoses included MEC (30 cases [39%]), suspicious for MEC (16 [21%]), non-MEC carcinoma (9 [12%]), suspicious for malignancy (SM) (2 [3%], malignant (M) (1 [1%]), SG and/or suspicious SG neoplasm (7 [8%]), atypical (3 [5%]), nonneoplastic (5 [6%]), nondiagnostic (2 [3%]), and benign SG neoplasm (1 [1%]). A total of 26% of low-grade (LG) cases were diagnosed as malignant in contrast to 87% malignant in high-grade (HG) cases. Cytomorphology depended on tumor grade. LG MEC contained intra- and/or extra-cellular mucin and more uniform cell and/or nuclear morphology, whereas cytologic atypia, anisonucleosis, and keratotic cells were more typical of HG tumors.

CONCLUSION

A malignant (M) or suspicious for malignancy (SM) cytologic interpretation was made in 76% of mucoepidermoid carcinoma (MEC) cases. In contrast to high-grade MEC (97% identified as M/SM), only 59% of low-grade (LG) MEC cases were interpreted as such, illustrating the continued diagnostic challenge posed by LG MEC using fine-needle aspiration biopsy.

Atypia of undetermined significance in the Milan System for Reporting Salivary Gland Cytopathology: Cystic versus non-cystic masses

The term "Atypia" has been employed to describe a wide spectrum of cytomorphologic features associated with reactive/inflammatory processes as well as those suspicious for neoplasms in cytology. Similar to other cytopathology reporting systems, the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has reserved the atypical category for cytology specimens lacking quantitative and/or qualitative cytomorphologic features to be diagnosed with confidence as either non-neoplastic or neoplastic. In MSRSGC, the atypical category is associated with a risk of malignancy and recommendation for clinical management. In this review, we discuss the value of atypical diagnostic category of MSRSGC in both cystic and non-cystic salivary gland lesions by evaluating our institutional case cohort.

Reclassification of salivary gland aspirates based on “The Milan system for reporting salivary gland cytology”: A five-year retrospective study

Introduction:

The Milan System for reporting salivary gland cytopathology helps standardize reporting systems across institutions, improve communication between clinicians and pathologists and guide the clinical management of patients.

Aims:

This study was undertaken to evaluate the utility of the Milan system classification in cytology reporting.

Settings and Design:

The present study is a retrospective study conducted over a period of five years in tertiary care centre.

Methods and Materials:

All the cases of salivary gland aspirates were reviewed and reclassified into six diagnostic categories according to the Milan system of reporting salivary gland cytology (MSRSGC). Cytological diagnosis was correlated with the histopathological diagnosis wherever available.

Results:

A total of 258 cases were classified using the Milan system as non-diagnostic (20.9%), non-neoplastic (26.3%), atypia of undetermined significance (4.7%), neoplasm benign (37.5%), neoplasm of uncertain malignant potential (3.5%), suspicious for malignancy (0.4%), and malignancy (6.6%). Cytohistological discordance was noted among 8/76 cases (10.5%). The sensitivity and specificity of FNAC were 75% and 98.5%, respectively. The risk of malignancy was 14.2% for Category I, 9% for II, 50% for III, zero for IVA and IVB, and 83.3% for category VI.

Conclusions:

The new classification system helps pathologists to standardize reporting leading to better clinical and surgical management.

A multi-institutional study of salivary gland cytopathology: Application of the Milan System for Reporting Salivary Gland Cytopathology in Japan

Background

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a risk‐stratification reporting system that was introduced in 2018. The objective of this multi‐institutional study was to evaluate the utility of the MSRSGC in Japan.

Methods

In total, 1608 fine‐needle aspiration samples with matching histologic diagnoses were retrieved from 12 large institutions in Japan. The diagnostic categories of the MSRSGC were assigned prospectively or retrospectively, and the results were compared with the histologic diagnoses.

Results

The cases were classified as follows: nondiagnostic, 18.1%; non‐neoplastic, 4.1%; atypia of undetermined significance, 11.5%; neoplasm‐benign, 43.7%; salivary gland neoplasm of uncertain malignant potential, 9.6%; suspicious for malignancy, 3.6%; and malignant, 9.4%. The risk of neoplasm and the risk of malignancy in each MSRSGC category were as follows: nondiagnostic, 72.9% and 13.4%, respectively; non‐neoplastic, 15.2% and 9.1%, respectively; atypia of undetermined significance, 77.9% and 24.9%, respectively; neoplasm‐benign, 99% and 1.8%, respectively; salivary gland neoplasm of uncertain malignant potential, 94.8% and 37%, respectively; suspicious for malignancy, 100% and 89.7%, respectively; and malignant, 100% and 99.3%, respectively. The accuracy of the MSRSGC for diagnosing neoplasms was 97.8%, and its accuracy for diagnosing malignancy was 97.3%. Institutions that used Romanowsky‐stained preparations had lower nondiagnostic rates and lower risks of neoplasm and malignancy in the non‐neoplastic category.

Conclusions

The MSRSGC is useful for risk stratification and quality control. Widespread use of the MSRSGC would improve the accuracy of salivary gland cytology and lead to better patient care in Japan.

This is the first multi‐institutional study of a large‐scale application of the Milan System for Reporting Salivary Gland Cytopathology in Japan. It demonstrates the usefulness of the Milan system in the diagnosis of salivary gland lesions and for the quality control of salivary gland cytology results.

Utility of the Milan system for reporting salivary gland cytopathology during rapid on-site evaluation (ROSE) of salivary gland aspirates

OBJECTIVE

Rapid on-site evaluation (ROSE) is a fine needle aspiration (FNA) technique for ensuring sampling adequacy and triaging samples. The Milan system for reporting salivary gland cytopathology (MSRSGC) is a standardised reporting system which aims to improve risk stratification. There is scant literature on the diagnostic value and agreement of MSRSGC on ROSE with final cytological diagnosis in salivary gland FNAs. We aimed to assess the concordance of MSRSCG categorisation and diagnosis on ROSE with final cytological and histological diagnosis.

METHODS

This prospective study included consecutive salivary gland FNAs for which ROSE was performed over a six-month period. MSRSGC category and diagnosis on ROSE were compared with the final cytological diagnosis and MSRSGC category, and histopathological diagnosis, where available.

RESULTS

Sixty salivary gland aspirates were included. The adequacy rate with ROSE was 100%. Using the MSRSGC classification during ROSE, 26 (43.2%) samples were categorised as benign neoplasm, 21 (35%) as malignant neoplasm, 9 (15%) as non-neoplastic, and one each (1.7%) belonged to the remaining four categories. MSRSGC categorisation on ROSE concurred with final the cytological diagnosis in 58/60 cases (96.7%). Discrepancies in MSRSGC categories on ROSE included one atypia of undetermined significance with final report as non-neoplastic, and one non-diagnostic as suspicious for malignancy. Good correlation of MSRSGC categories on ROSE with final histopathological diagnosis (88.9% concordance) was also noted.

CONCLUSIONS

MSRSGC on ROSE shows good concordance with final cytology and histopathology diagnosis, indicating that categorisation according to MSRSGC has utility in ensuring that adequate material is obtained and triaged appropriately for the diagnosis of salivary gland aspirates.

Application value of shear wave elastography in salivary gland tumors

OBJECTIVE

The aims of this study were to retrospectively analyse the values of shear wave elastography (SWE) in differential diagnosis of salivary gland tumors (SGT).

METHODS

A total of 56 patients with salivary gland lump(s) were examined by SWE for measuring and comparing the differences in various Young's modules (malignant tumor (MT) and benign tumor (BT), parotid tumor (PA) and adenolymphomas (AL), etc.). All the cases were confirmed by surgery or fine needle aspiration pathology.

RESULTS

The 56 SGT cases included 10 cases MT, 27 cases of PA, 11 cases of AL, and 8 cases of other BT. There was no statistical significance in Young's modules between group BT and group MT (both P > 0.05); the differences between group PA and group AL were statistically significant (P < 0.05), and the corresponding ROC curve analysis found that the diagnostic value of the maximum Young's modulus was the highest with the best cut-off values and AUC as 32.4 KPa and 0.805. The sensitivity, specificity, and Yoden index of the diagnosis of PA and AL were 70.4%, 81.8%, and 0.522, respectively.

CONCLUSIONS

SWE can differentially diagnose PA and AL while not MT and BT in SGT.

Application of the Milan System for Reporting Salivary Gland Cytopathology to cystic salivary gland lesions

BACKGROUND

Cystic salivary gland lesions present diagnostic challenges on fine-needle aspiration (FNA) specimens that are related to sampling limitations and a broad differential diagnosis. This study evaluated the benefit of applying the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) to a series of cystic salivary gland lesions.

METHODS

The pathology archives at the Johns Hopkins Hospital were searched to identify cystic salivary gland FNA specimens over a 19-year period (2000-2018). Patient demographics, cytomorphologic features, and clinical and surgical follow-up were recorded. The MSRSGC was applied to the cases. The risk of malignancy (ROM) and the risk of neoplasia (RON) were calculated for each category.

RESULTS

One hundred seventy-eight cases were identified (96 males and 82 females) with a mean age of 53 years (range, 4-90 years). After the MSRSGC was applied, there were 52 nondiagnostic cases (29.2%), 80 nonneoplastic cases (44.9%), 35 cases of atypia of undetermined significance (AUS; 19.7%), 3 benign neoplasms (1.7%), 3 salivary gland neoplasms of uncertain malignant potential (SUMP; 1.7%), 4 cases suspicious for malignancy (SFM; 2.2%), and 1 malignant case (0.6%). One hundred fifty-six of the 178 patients (87.6%) had follow-up data available. The RON and ROM values for cases with surgical follow-up were 33.3% (3 of 9) and 22.2% (2 of 9) for the nondiagnostic category, 42.9% (9 of 21) and 19% (4 of 21) for the nonneoplastic category, 76.5% (13 of 17) and 29.4% (5 of 17) for the AUS category, 100.0% (2 of 2) and 50.0% (1 of 2) for the SUMP category, and 100% (2 of 2) and 100% (2 of 2) for the SFM category, respectively.

CONCLUSIONS

Applying the MSRSGC to cystic salivary gland lesions improves patient management by preventing unnecessary surgery for nonneoplastic conditions. The ROM was highest in the SFM category (100%), which was followed by the SUMP, AUS, nondiagnostic, and nonneoplastic categories. Less than adequate specimens may increase the diagnosis of AUS.

Risk stratification and clinical outcome in the atypia of undetermined significance category in the Milan System for Reporting Salivary Gland Cytopathology

BACKGROUND

Atypia of undetermined significance (AUS) is a category of the Milan System for Reporting Salivary Gland Cytopathology that refers to salivary gland fine-needle aspiration (FNA) specimens that cannot be definitively diagnosed as neoplastic or nonneoplastic.

METHODS

The AUS FNA samples were selected from a large academic institution from 2008 through 2018. The AUS cases were divided into 6 subgroups. The risk of malignancy (ROM), risk of neoplasm (RON), and clinical outcomes for each subgroup were evaluated.

RESULTS

A total of 123 cases were found (76 males and 47 females with a mean age of 62 years [range, 6-94 years]). The parotid gland was the most common FNA site (103 cases), followed by the submandibular gland (9 cases). The overall RON and ROM were 63% and 47%, respectively. Among the subgroups, salivary gland lymph nodes or lymphoid lesions was the most common diagnosis (42%), whereas mucinous cystic lesions with no or a scant epithelial component was the least common (2%). The specimens with preparation artifacts category had the highest RON and ROM (100% for both), whereas the reactive and reparative atypia indefinite for a neoplasm category had the lowest RON and ROM (7% for both). The salivary gland lymph nodes or lymphoid lesions indefinite for a lymphoproliferative disorder category had the second highest RON and ROM at 77% and 74%, respectively.

CONCLUSIONS

The overall RON and ROM for the AUS category were 63% and 47%, respectively. The RON and ROM varied among the different AUS subgroups, being highest in the specimens with preparation artifacts category and lowest in the reactive and reparative atypia category, thereby demonstrating the importance of subgrouping in the AUS specimens.

Lymphoepithelial Cyst of the Salivary Gland in a Small Ruminant Lentivirus-Positive Goat

Simple Summary

This study presents the first case of a lymphoepithelial cyst (LEC) adjacent to the salivary gland in a goat seropositive for the small ruminant lentivirus (SRLV). Immunohistochemistry detected the antigen of caprine arthritis-encephalitis virus (CAEV) in the LEC, salivary gland, and lung tissue. In human patients, a LEC of the major salivary gland is an uncommon benign lesion and may be the early clinical manifestation of human immunodeficiency virus (HIV) infection. The present report provides useful information on the comparative aspect of LEC in an animal infected with CAEV, one of the SRLVs usually associated with chronic infection. Although many hypothetic theories were proposed, the etiopathogenesis of LEC is still debated. In this study, we present the histopathological description of LEC, supported by histochemistry and immunohistochemistry.

Abstract

The lymphoepithelial cyst (LEC) of the major salivary gland is a rare lesion described in medical literature. It is found in human immunodeficiency virus (HIV)-infected patients and considered an early manifestation of this infection. Despite the variety of theories, the origin of this lesion remains controversial. No veterinary studies on LEC have been published so far. This study is the first-ever that aims to describe histopathological, histochemical, and immunohistochemical features of a LEC located adjacent to the salivary gland of a goat. The goat proved seropositive for the small ruminant lentivirus, showed clinical signs of caprine arthritis-encephalitis, and had caprine arthritis-encephalitis virus (CAEV)-infected cells in the lung. The histopathology revealed a cystic lesion lined mainly with squamous epithelium surrounded by a lymphoid component, containing a mucus-negative material and a few nonbirefringent structures corresponding to amylase crystalloids. Using immunohistochemistry, CAEV-positive cells were detected in macrophages, LEC epithelial cells, and the salivary gland. The B cells were mainly in the germinal centres, the intraepithelial lymphocytes expressed CD3 and Bcl-2, and the proliferative activity was low. This study showed that LEC had many similar histological and immunohistochemical features to those seen in humans. However, further studies are required in this respect.

An audit of cytopathology in the oral and maxillofacial region: 18 years of experience

INTRODUCTION

The aim of this study was to perform an audit of oral and maxillofacial specimens submitted for cytological diagnosis to verify the importance of this complementary examination.

METHODS

A retrospective analysis of our institutional cytopathology database was performed over an 18-year period. Clinical information and cytological data were collected. Associations between independent variables and outcomes were assessed using the Pearson χ² test or Fisher's test, with a 5% significance level. When available, the histological diagnosis was compared with cytological diagnosis to identify the percentage of agreement and the specificity, sensitivity and accuracy of cytology in identifying malignant neoplasms.

RESULTS

A total of 1082 cases were identified, which included 65 different cytological diagnoses. Exfoliative cytology (EC) was performed in 312 cases (29.1%) and fine needle aspiration cytology (FNAC) in 770 cases (70.9%). EC was mainly employed to diagnose oral infectious diseases (P < 0.001) and FNAC to diagnose neoplasms, cystic, reactive and miscellaneous lesions (P < 0.001). Cell-block was performed in 555 FNAC cases (51.3%). Panoptic, Papanicolaou and haematoxylin-eosin staining were performed in FNAC and periodic acid-Schiff in EC (P < 0.001). In 211 cases (19.5%), the histological diagnosis was available and the percentage agreement with the cytological diagnosis was 41.2%. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy to identify malignant neoplasms were 84.6%, 100%, 100%, 77.8% and 90.0%, respectively.

CONCLUSIONS

EC was mainly performed for diagnosis of infectious diseases and FNAC for diagnosis of salivary gland tumours, odontogenic lesions, reactive lesions and cervical metastasis.

Oncocytic mucoepidermoid carcinoma (OMEC) of the parotid gland in a 12-year-old patient: A diagnostic challenge on cytology

Mucoepidermoid carcinoma is the most common malignant salivary gland neoplasm comprising approximately 10% of all tumours of the major salivary gland. Owing to a plethora of morphological variations, it poses a diagnostic challenge on fine-needle aspiration cytology. Oncocytic variant of mucoepidermoid carcinoma is a rare subtype seen in the age group of 20-80 years. It is crucial to make the correct diagnosis on cytology as it has therapeutic implications. Oncocytes can be present in a wide range of salivary gland lesions ranging from non-neoplastic conditions to benign and malignant lesions. We report a case of oncocytic mucoepidermoid carcinoma of the parotid gland in a 12-year-old boy which is the youngest age reported for the same. On cytology, this case was initially diagnosed as Warthin's tumour and was supported by radiology. However, histomorphological findings clinched the diagnosis of an oncocytic variant of mucoepidermoid carcinoma with the aid of immunohistochemistry.

Magnetic Resonance Imaging Findings of Crystalloid-Containing Parotid Cysts

Crystalloids are occasionally encountered on fine needle aspiration of cystic parotid lesions. This goal of this study was to retrospectively characterize the MRI features of a series benign crystalloid-containing parotid cysts. A total of 4 patients with fine needle aspiration findings of crystalloids and available parotid MRI scans were identified. Review of the imaging revealed that the cystic lesions contain layering material that corresponds to crystals.

Salivary gland disease in the era of COVID-19 pandemic

Coronavirus disease 2019 (COVID‐19) pandemic forced significant changes in current approach to outpatient evaluation of common otolaryngology complaints as hospitals around the world are trying to limit the spread of the virus and to preserve health care resources. These changes raise a lot of questions regarding patient triage and treatment decisions in clinical situations when it is unclear if the workup and management can be postponed. In this communication, we present our approach to evaluation and triage of new patients with complaints concerning for salivary gland disease.

Cytologic grading of primary malignant salivary gland tumors: A blinded review by an international panel

BACKGROUND

Fine needle aspiration (FNA) is commonly used for the preoperative evaluation of salivary gland tumors. Tumor grade is a key factor influencing clinical management of salivary gland carcinomas (SGCs). To assess the ability to grade nonbasaloid SGCs in FNA specimens, an international panel of cytopathologists convened to review and score SGC cases.

METHODS

The study cohort included 61 cases of primary SGC from the pathology archives of 3 tertiary medical centers. Cases from 2005 to 2016 were selected, scanned, and digitized. Nineteen cytopathologists blinded to the histologic diagnosis reviewed the digitized cytology slides and graded them as low, high, or indeterminate. The panelists' results were then compared to the tumor grades based on histopathologic examination of the corresponding resection specimens.

RESULTS

All but 2 of the 19 (89.5%) expert panelists review more than 20 salivary gland FNAs per year; 16 (84.2%) of the panelists work at academic medical centers, and 13 (68.4%) have more than 10 years' experience. Participants had an overall accuracy of 89.4% in the grading of SGC cases, with 90.2% and 88.3% for low- and high-grade SGC, respectively. Acinic cell carcinoma and mucoepidermoid carcinoma had the highest degree of accuracy, while epithelial-myoepithelial carcinoma and salivary duct carcinoma had the lowest degree of accuracy. As expected, the intermediate-grade SGC cases showed the greatest variability (high-grade, 42.1%; low-grade, 37.5%, indeterminate, 20.4%).

CONCLUSION

This study confirms the high accuracy of cytomorphologic grading of primary SGC by FNA as low- or high-grade. However, caution should be exercised when a grade cannot be confidently assigned.

Cytomorphological findings in diagnosis of Warthin tumor

Background/aim

To define the cytomorphologic findings leading to difficulties in diagnosis of Warthin tumors (WTs).

Materials and methods

Forty-eight histopathologically diagnosed WT patients who had fine needle aspiration cytology preoperatively were reevaluated for defining the presence or absence of lymphocytes, oncocytic cell layer, oncocytic cell papillae, granular debris background, mucoid background, macrophages, polymorphonuclear cells, mast cells, squamous-like cells, atypical vacuolated cytoplasmic cells, and giant cells.

Results

Forty-seven tumors were in the parotid gland and one in the submandibular gland. There were 37 (77%) male and 11 (23%) female patients. Cytopathologically in 36 patients the diagnosis was benign neoplasm (WT); in 6, other benign entities; and in 6, suspicious for malignancy. The main characteristic cytomorphologic features of WTs were as follows: 92% lymphoid cells, 83% oncocytic cell layers, and 67% granular debris background. These percentages were 67%, 17%, and 17% in the benign cytology group and 67%, 50%, and 17% in the suspicious for malignancy group, respectively.

Conclusion

Absence or lack of main features of WTs with or without presence of squamous-like cells, vacuolated cytoplasmic cells, and inflammatory reaction may cause diagnostic dilemma. The presence of the mast cells accompanied by epithelial tissue was striking for WT diagnosis.

Salivary Gland FNA Diagnostics in a Real-Life Setting: One-Year-Experiences of the Implementation of the Milan System in a Tertiary Care Center

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was introduced in 2018 following other organ specific cytopathological reporting systems and it aimed at bringing a practical, evidence-based, user-friendly classification system with characterization and management algorithms. At the Department of Pathology, Fimlab Laboratories, Tampere, Finland all salivary fine needle aspirations (FNAs) have been given cytopathological diagnoses according to the MSRSGC since January 2018. Analyses of a one-year-period (January 2018–December 2018) consisted of 183 salivary FNA samples from 138 patients with correlation to histopathology in 90 cases with surgical follow-up. The MSRSGC performance in patient based analysis was as follows: accuracy was 90.9%, sensitivity was 61.5%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 89.4%, respectively. Risks of malignancy (ROMs) in MSRSGC categories were: 0.0% (0/15) in non-diagnostic category, 100.0% (1/1) in non-neoplastic category biased by only one falsely-negative lymphoma case, 14.3% (1/7) in atypia of undetermined significance category, 0.0% (0/28) in benign neoplasm category, 27.3% (3/11) in neoplasm of uncertain malignant potential category, and 100% for both suspicious for malignancy (4/4) and malignancy (4/4) categories, respectively. The MSRSGC has been proven as a reliable classification system in salivary gland FNA routine diagnostics in a tertiary care center.

Fine Needle Aspiration Cytology for Neck Masses in Childhood. An Illustrative Approach

The primary indication of fine-needle aspiration cytology of the head and neck region is a thyroid nodule or a mass located in the cervical area or the head. Although a thyroid nodule may raise the suspicion of malignancy, less than one in 20 cases results in a carcinoma. In addition, the list of differential diagnoses is quite different according to the age of the patient. A number of benign lesions, such as branchial cysts, sialadenosis, and sialoadenitis are often seen in childhood and youth. The malignant lesions that are on the top of the list of a pediatric mass of the head and neck (H&N) region include rhabdomyosarcoma, neuroblastoma, and papillary carcinoma of the thyroid gland. This critical review of the diagnostic features of a pediatric mass of the H&N region is accompanied by panels of several cytology features that may be of help to the cytopathologist and clinician.