Fine needle aspiration diagnosis of benign oncocytic lesions of the head and neck associated with false positive 18F-fluorodeoxyglucose uptake on positron emission tomography scan.

INTRODUCTION: 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT) has become the mainstay for staging and post-therapy surveillance of cancer as malignant neoplasms generally demonstrate higher FDG uptake that benign entities. However, there are certain benign lesions, most notably oncocytic tumors, that can display very high uptake and fine needle aspiration (FNA) is usually done to confirm malignancy. Therefore, it is important to recognize that benign oncocytic lesions of the head and neck may also present as FDG-avid lesions to avoid a diagnostic pitfall. METHODS: Electronic search of institutional surgical and cytopathology archives was conducted to identify cases of benign oncocytic lesions involving the head and neck region diagnosed by FNA from January 2012 to April 2022. Chart review was used to assess whether lesions were initially discovered via PET scanning. RESULTS: One hundred and twenty-five cases of oncocytic lesions were identified; 12 (9%) PET positive lesions were identified in the head and neck region from patients being evaluated for metastasis or for suspicion of malignancy. Cytopathology of all 12 cases demonstrated benign oncocytic lesions; eight (67%) of these cases were consistent with Warthin tumor, one (8.3%) was a benign oncocytic lesion, and one (8.3%) was consistent wit a parathyroid adenoma. Most (58%) of the PET-positive lesions were in parotid region, two from thyroid gland (17%), one from submandibular gland (8%), one from paratracheal area (8%). The PET scan SUVs ranged from 3.3 to 19.5 g mL-1. CONCLUSIONS: Oncocytic lesions including Warthin tumors can result in false-positive FDG uptake on PET scans. Clinicians and cytopathologists should be aware of PET-positive benign oncocytic head and neck lesions.

Primary intranodal Warthin-like variant of mucoepidermoid carcinoma.

This report describes a rare case of primary intranodal Warthin-like mucoepidermoid carcinoma (WL-MEC) presenting as a left level II lymph node mass in a 48-year-old man. Warthin-like mucoepidermoid carcinoma is a recently defined variant of MEC that bears a close histologic resemblance to Warthin tumor. Whereas MEC has readily identifiable key histologic features that render diagnosis relatively straightforward, WL-MEC is a challenging diagnosis due to overlapping histologic features and only limited case reports in the literature. This case was initially diagnosed as primary intranodal MEC after the exclusion of metastasis by imaging. It was not until years later, upon review of historic cases, that the diagnosis of WL-MEC was established. This diagnosis was further supported by molecular testing that was not available at the time of the original diagnosis.

Bilateral intra-lymph node Warthin's tumor as a potential diagnostic pitfall mimicking metastatic carcinoma.

Warthin's tumor (WT) is a benign and frequent salivary gland tumor primarily affecting the parotid gland. In some cases, this tumor can involve the extra parotid region and affect cervical lymph nodes. Fine-needle aspiration can be the first step in the diagnostic approach to lymphadenopathy; however, specimens from intra-nodal WT can present a potential pitfall, leading to a misdiagnosis of metastasis. Here, we report an unusual case of a patient with bilateral WT in parotid lymph nodes misdiagnosed as metastases. In addition, we highlight the cytopathological aspects of WT to alert cytopathologists about this challenging diagnosis.

Uncommon Coexistence of Pleomorphic Adenoma and Warthin's Tumor in a Painfully Swollen Left Parotid Gland: A Surgical Case Report.

BACKGROUND Benign pleomorphic adenoma is the most common primary tumor of the salivary glands and mainly arises in the parotid gland. Warthin's tumor, or papillary cystadenoma lymphomatosum, represents <30% of benign parotid tumors. The simultaneous occurrence of multiple parotid tumors is rarely described - depending on the corresponding histology (different/identical), the time of their occurrence (synchronous/metachronous), as well as their location (unilateral/bilateral), multiple parotid tumors can be further sub-classified. CASE REPORT We describe the case of a 54-year-old female patient with progressive and painful swelling of the left parotid gland for the last 6 months. During extra-oral examination, a bulging, displaceable mass of approximately 3 cm was determined. A subsequent MRI (magnetic resonance imaging) examination revealed a multifocal lesion but failed to provide a decisive clue as to the tumor entity of the lesion, and a lateral (superficial) parotidectomy was performed. Postoperative histomorphological interpretation allowed the final pathological diagnosis of synchronous, unilateral occurrence of a pleomorphic adenoma as well as a Warthin's tumor. CONCLUSIONS This report presents a rare case of synchronous unilateral parotid tumors and supports that benign pleomorphic adenoma and Warthin's tumor are the most common associations. Since clinical examination, MRI imaging, and even cytological assessment could be misleading in the detection of synchronous ipsilateral multiple parotid gland tumors, our report also highlights the importance of timely and accurate diagnosis with histopathology to plan surgery and to exclude malignant transformation, which is a rare but important association with both types of primary salivary gland tumor.

Warthin-like mucoepidermoid carcinoma of the parotid gland: Clinicopathological observation and literature review.

Warthin tumor (WT)-like mucoepidermoid carcinoma resembles the histologic pattern of WT and pathologists unaware of this possibility may misdiagnose it as WT with squamous and mucous epithelium metaplasia or WT malignant transfer into mucoepidermoid carcinoma. The present study reported a case of a 41-year-old Chinese female with a solitary mass in the left parotid gland. In this case, microscopic observation revealed prominent lymph node stroma and multiple cystic structures similar to those seen in WT. However, it lacked the two layers of oncocytic epithelial tissue characteristic of WT. Furthermore, fluorescence in situ hybridization detected MAML2 rearrangement in the case. Considering the histological findings, this case was diagnosed as WT-like mucoepidermoid carcinoma. The present case report provides pathological and clinical features to differentiate it from WT malignant transition into mucoepidermoid carcinoma, WT with squamous and mucous epithelium metaplasia and non-sebaceous lymphadenoma-like mucoepidermoid carcinoma. In conclusion, WT-like mucoepidermoid carcinoma as a special subtype of mucoepidermoid carcinoma has special histological characteristics, which required further observations and more case reports to clearly define this variant.

Warthin-like papillary carcinoma: Case report.

Warthin-like papillary thyroid carcinoma is a rare variant of papillary carcinoma with a very good prognosis. It is often associated with lymphocytic thyroiditis. Due to its typical histological picture resembling Warthin's salivary gland tumor, the histological diagnosis is not difficult, usually does not require an accompanying immunohistochemical examination and is based on the presence of nuclear features typical of papillary carcinoma and the presence of oncocytes in a background of rich lymphocyte infiltrate. The preoperative cytologic examination is challenging, as many other lesions may have a similar picture. Women are more likely to get affected. It appears a decade earlier than the classic variant. Clinically, it presents similarly to a conventional papillary carcinoma. In our case report, we would like to present the case of a 56-year-old woman with non-toxic multinodular goiter, in whom the presence of this rare variant of papillary carcinoma was revealed by histological examination.

Nonsebaceous Lymphadenoma of the Salivary Glands: A Potential Overdiagnosis Pitfall.

Nonsebaceous lymphadenoma is a rare benign salivary tumor. It is easily misdiagnosed as lymphoepithelial carcinoma, leading to overtreatment. Some patients experience sequelae after undergoing cervical lymph node resection and adjuvant treatment, so it is critical to distinguish these entities. We describe the histopathological and immunohistochemical features of this rare entity in 3 cases and discuss the differential diagnosis and histogenesis. Nonsebaceous lymphadenoma can be distinguished from lymphoepithelial carcinoma by the following histological features: There is a lymph node-like form at low magnification, with prominent proliferating epithelial nests but no destructive growth pattern; variable numbers of tubuloglandular components are always seen in proliferating epithelial nests, which transition to cystically dilated salivary ducts; no lesion necrosis exists; and mitotic figures are absent or rare. No patients experienced recurrence during the 8- to 69-month (mean, 29 months) follow-up.

Warthin tumor complicated with T-lymphoblastic lymphoma: a case report.

Warthin tumor is a benign salivary gland tumor comprising ductal epithelium and lymphoid stroma. To date, reports about the malignant transformations of intraepithelial and lymphoid components in Warthin tumor are extremely rare; lymphoid malignant transformation into B-cell lymphoma is particularly rare in combination with T-cell lymphoma. The case of Warthin tumor complicated with T-lymphoblastic lymphoma is reported to emphasize the importance of a careful light microscopic evaluation of lymphoid tissue in Warthin tumor for identifying occult lymphoma presence, reducing misdiagnosis and missed diagnosis, and determining a timely treatment.

A rare case of sebaceous lymphadenoma: Cytohistological correlation of preoperative cytomorphologic findings.

We are presenting a case of a 74-year-old female with a parotid gland mass. Fine-needle aspiration (FNA) of the mass demonstrated cohesive groups of epithelial cells with overall bland-appearing nuclei and abundant vacuolated cytoplasm, consistent with sebaceous cells, in a background of polymorphous lymphocytes, scattered histiocytes, and adipose tissue. Immunostains showed that the epithelial cells stain positive for p63, but negative for CD117 and DOG-1. CD3 and CD20 showed a mixture of T- and B-cells. On the PAP-stained slides, there were numerous sac-like structures, consistent with myospherules. These findings were suggestive of neoplasm with sebaceous differentiation. The main differential diagnosis included sebaceous adenoma, sebaceous lymphadenoma, and other benign lesions with sebaceous differentiation. The parotid mass was resected. Histology sections demonstrated a well-circumscribed neoplasm with multicystic epithelial component and surrounding lymphoid infiltrate, consistent with sebaceous lymphadenoma. Sebaceous lymphadenoma (SLA) is a rare benign salivary gland neoplasm that is most commonly seen in the parotid gland. Preoperative FNA diagnosis of sebaceous neoplasms is challenging. To the best of our knowledge, this is the third case of sebaceous lymphadenoma diagnosed preoperatively. In this manuscript, we detail the epidemiological characteristics and histogenesis of sebaceous salivary gland neoplasms, and the cytomorphologic differential diagnosis of SLA with key diagnostic features of each entity.

Cystic lesion in parotid region: an unexpected diagnosis.

Benign tumours of salivary glands represent 2%-3% of all tumours and parotid gland is most often affected. Keratocystoma is a rare benign tumour with multilocular cystic lesions filled with keratin materials. Histologically, it is characterised by solid epithelium islands containing keratinised lamellae with multicystic spaces. We report a case of a woman in her mid-70s with painless mass in her left parotid gland which increased in size over 1 year. Ultrasound scan revealed a 38×20 mm diameter hypoanechoic mass. Neck CT with contrast medium and fine needle aspiration were performed with diagnostic hypothesis of Warthin tumour. So, extracapsular parotid dissection with no facial nerve damage was performed. Histological examination revealed a keratocystoma. The patient had a 16-month follow-up without signs of relapse or malignancy. Despite its rarity, keratocystoma must be considered among the possible differential diagnostic hypotheses when we find parotid masses, to ensure the best treatment to the patient.

Multiple synchronous neoplasms in the ipsilateral parotid gland: case series.

BACKGROUND: Multiple synchronous neoplasms in the ipsilateral parotid gland are very rare. We intend to analyze the clinical characteristics and treatment results of multiple synchronous neoplasms in the ipsilateral parotid gland managed at our hospital. METHODS: The study included 21 patients of multiple synchronous neoplasms in the ipsilateral parotid gland from January 2010 to December 2020. RESULTS: Twenty-one cases of multiple synchronous neoplasms in the ipsilateral parotid gland were identified among 994 cases of parotid surgery, with a frequency of 2.1%. Multiple synchronous neoplasms in the ipsilateral parotid gland occurred in all males and one female. Except for one case, all of them involved histopathologic neoplasms. Warthin tumor (n=19, 90.5%) was the most common. Among 21 lesions, there were 9 patients of right parotid gland, 4 patients of left parotid gland, and 4 patients of bilateral parotid gland. The main symptoms were slowly enlarging mass within the parotid gland (n=20), followed by incidental detection (n=1). CONCLUSIONS: Clinicians should be aware of the possibility of multiple synchronous neoplasms in the ipsilateral parotid gland. Preoperative imaging tests, clinical examinations, and careful palpation during surgery are important for accurate diagnosis and treatment.

Warthin-like mucoepidermoid carcinoma of the parotid gland: a clinicopathological analysis of two cases.

Mucoepidermoid carcinoma (MEC) is the most common malignant tumour of the salivary gland, primarily involving the parotid gland. Here, the cases of two patients, aged 47 and 67 years, respectively, who underwent surgery for pathologically confirmed Warthin-like MEC of the parotid gland between January 2019 and December 2019 in Anyang Tumour Hospital, are described. In each case, the tumour consisted of epithelial and lymphoid cell components, covered with two or more layers of epithelium, with visible scattered mucous cells, and lymphoid stroma with a large number of lymphocytes and germinal centres formed. Most importantly, the tumours lacked the well-organized, bilayered oncocytic epithelial structure that is characteristic of Warthin's tumour. Mastermind like transcriptional coactivator 2 (MAML2) gene rearrangements were identified in the tumour cells using break-apart fluorescence in situ hybridization (FISH) probes, confirming the diagnosis of Warthin-like MEC. Post-operatively, patients have remained disease free for 31 and 27 months, respectively. Warthin-like MEC of the parotid gland is rare and is often misdiagnosed as metaplastic Warthin's tumour. Diagnosis depends mainly on the unique clinicopathologic features together with FISH analyses.

Differential diagnostic value of tumor morphology, long/short diameter ratio, and ultrasound gray-scale ratio for 3 parotid neoplasms.

OBJECTIVE: The objective of this study was to evaluate the value of tumor morphology, long-to-short diameter ratio (L/S), and ultrasound gray-scale ratio (UGSR) in the differential diagnosis of 3 parotid neoplasms. STUDY DESIGN: Preoperative ultrasound images of 17 patients with a malignant tumor (MT), 48 patients with pleomorphic adenoma (PA), and 39 patients with adenolymphoma (AL) were analyzed for imaging features and gray-scale histograms. Tumor morphology, L/S, and UGSR of MT, PA, and AL were compared. Receiver operating characteristic analysis of area under the curve (AUC), sensitivity, and specificity were used to measure the differential diagnostic efficacy of L/S, UGSR, and both combined with tumor morphology. RESULTS: Morphologic features, L/S, and UGSR differed significantly in various pairwise comparisons of the 3 tumor types. Acceptable discrimination was detected between MT and AL with UGSR alone (AUC = 0.771) and between PA and AL with L/S and UGSR combined (AUC = 0.741). The combination of tumor boundary with UGSR yielded excellent discrimination between MT and PA (AUC = 0.853) and between MT and AL (AUC = 0.885), with sensitivity and specificity values greater than 0.800. CONCLUSIONS: These ultrasound parameters, alone or in combination, can provide a method for accurate presurgical differential diagnosis of parotid tumors.

The Milan System classification of Warthin tumor: A large institutional study of 124 cases highlighting cytologic features that limit definitive interpretation.

BACKGROUND: Fine-needle aspiration (FNA) is highly accurate for the diagnosis of Warthin tumor (WT). However, there is a minor subset of WT cases that are more challenging to interpret. The goal of this study is to identify factors that limit definitive diagnosis of WT on FNA. METHODS: All WT surgical specimens diagnosed during a 6.5-year study period were retrospectively identified and the preceding cytologic specimen diagnostic categories were analyzed. Of particular interest were WT cases with indeterminate or malignant interpretations. Cases that noted squamous or mucinous change in either the surgical or cytologic reports were also reviewed. RESULTS: A total of 157 WT surgical specimens were identified, with 124 (79.0%) having prior FNAs. The distribution of cytologic diagnostic categories was 12 (9.7%) nondiagnostic, 10 (8.1%) nonneoplastic, 13 (10.5%) atypia of undetermined significance (AUS), 82 (66.1%) neoplasm: benign, 4 (3.2%) salivary gland neoplasm of uncertain malignant potential (SUMP), 2 (1.6%) suspicious for malignancy, and 1 (0.8%) malignant. Of the 20 cases in indeterminate/malignant categories, a majority noted either squamoid (9 of 20) or mucinous (2 of 20) changes. The remainder noted scant cellularity as a limiting factor to interpretation. Additionally, 27 cases mentioned squamous or mucinous change in the surgical or cytology report, with a wide spectrum of cytologic categorization including 2 (7.4%) nondiagnostic, 2 (7.4%) nonneoplastic, 7 (25.9%) AUS, 8 (29.6%) neoplasm: benign, 4 (14.8%) SUMP, 2 (7.4%) suspicious for malignancy, and 1 (3.7%) malignant. CONCLUSIONS: This study identified 2 key causes for indeterminate or misclassification of WT on FNA: specimen hypocellularity and metaplastic changes. Recognition of the potential for squamous and mucinous metaplastic changes combined with observance of some helpful diagnostic clues such as the presence of crystalloids may aid in preventing diagnostic pitfalls.

Warthin-Like Mucoepidermoid Carcinoma: A Morphological Spectrum - A Report of 3 Cases with Histological and Cytological Findings and Review of the Literature.

BACKGROUND: Mucoepidermoid carcinoma (MEC) showing Warthin's tumor (WT)-like features is a low-grade malignancy which should be differentiated from WT. Morphological features may be distinctly different in each case, causing diagnostic difficulties. CASE PRESENTATION: Three cases were presented and discussed with their morphologies. All cases that presented with a mass in the parotid gland went to parotidectomy, and all had preoperative fine-needle aspirations (FNAs). Case 1 was a 16-year-old female; FNA was suggestive of WT and initially interpreted as WT histologically. Case 2 was a 27-year-old male; FNA was interpreted as noninformative due to the presence of cyst fluid only. Case 3 was a 53-year-old male and cytologically was found to be suspicious for MEC which contained squamous and goblet cells on a mucoid background. On histopathological examination, case 2 and case 3 were morphologically consistent with low-grade MEC with WT-like features. Prominent lymphoid stroma and the cystic pattern were the characters of these tumors. Case 1 had the classical WT appearance with some mucinous and squamous metaplasia which could only be interpreted as MEC after the detection of MAML2 rearrangement by FISH. The other 2 showed either focal or relatively diffuse usual low-grade MEC findings, and case 3 was also confirmed by MAML2 rearrangement. CONCLUSION: Cytological and histopathological features revealed a spectrum. Differentiating WT-like MECs from ordinary WTs may be challenging. On the one end of the spectrum, they may look very much like WT, and on the other end, even though usual MEC features are present, still, WT-like appearance may pose diagnostic difficulty. Showing MAML2 rearrangement in these cases is very helpful. The presence of mucinous and squamous cells in an otherwise WT-like looking tumor should be alarming for MEC, and if possible, each case should be analyzed for MAML2 rearrangement.

Ulcerative Warthin Tumor: A Case Report and Review of the Literature.

Warthin tumor with ulceration of the surrounding skin is extremely rare, making it difficult to differentiate from parotid cancer in the clinical setting. We report a 65-year-old man with a Warthin tumor in the right parotid gland that had ulceration of the overlying skin. The patient presented with right upper neck mass 2 years ago. Ultrasound and fine needle aspiration were done, and Warthin tumor was suspected. One year later, the mass was enlarged with ulceration of the skin. Superficial parotidectomy with fusiform excision of the skin was performed, and histopathological diagnosis revealed a Warthin tumor with inflammatory change. We proposed that this unique manifestation may have been induced by fine needle aspiration, enlargement of the tumor, and ischemic changes secondary to pulmonary arteriovenous malformations.

Value of dynamic contrast enhanced MRI in differential diagnostics of Warthin tumors and parotid malignancies.

To define an algorithm for differential diagnostics of parotid malignancies and Warthin tumors (WTs) based on dynamic contrast enhanced MRI (DCE-MRI). 55 patients with parotid tumors treated surgically were analyzed. Of which, 19 had parotid malignancy and 36 had WTs confirmed with postoperative histopathological examination. Accuracy of DCE-MRI parameters (Tpeak and WR) was compared with the histopathological diagnosis. ROC analysis was performed to determine sensitivity and specificity of DCE-MRI with various Tpeak and WR cut-off values. WT showed significantly lower median Tpeak and higher median WR than malignant lesions. The cut-off values for Tpeak and WR providing maximum sensitivity (84.2%) and specificity (86.1%) for malignant tumors were Tpeak > 60 s and WR ≤ 30%. Different diagnostic algorithm, i.e., lower cut-off value for Tpeak (Tpeak = 60 s), increases sensitivity of DCE-MRI in differentiating parotid malignancies from WTs. However, WR > 30% seems to be a key diagnostic criterion for benign lesions. Precise and reliable preoperative diagnostics of parotid tumors aids in careful surgical planning, thereby assisting in achieving sufficient surgical resection margins and facial nerve preservation.

Cytomorphology of Warthin-like variant of papillary thyroid carcinoma: A diagnosis not to be missed.

The authors have elaborated the cytological features of Warthin-like variant of papillary thyroid carcinoma (WLPTC) presenting unusually with nodal metastasis in a 43-year-old lady, and which was reported on cytology as papillary thyroid carcinoma (PTC) with lymphocytic thyroiditis.

Remote cytological diagnosis of salivary gland lesions by means of precaptured videos.

OBJECTIVE: The objective of this study was to investigate the feasibility of implementing videos captured by static telecytological applications for remote cytological diagnosis of fine needle aspiration (FNA) specimens from salivary gland lesions. METHODS: The current study was performed on 102 specimens from patients referred to the Alpha Prolipsis Cytopathology Department for preoperative evaluation of salivary gland lesions. In all cases, surgical excision followed the initial cytological diagnosis. (benign lesions, 11; benign neoplasms, 68; malignant neoplasms, 23). Videos were transferred via file transfer protocol to password-protected accounts for remote review by three independent cytopathologists. In addition to diagnosis, reviewers commented on overall digital video quality. Contributor's and reviewer's diagnoses were collected, recorded and statistically evaluated. RESULTS: Statistical evaluation of cytological diagnoses detected no significant difference in diagnostic accuracy between the diagnoses proffered on the basis of precaptured videos and conventional slides. The overall interobserver agreement was ranging from substantial to almost perfect with κ values of 0.71-0.89. CONCLUSIONS: Videos production by static telecytology applications can be used as an alternative method for telecytological diagnosis of salivary glands FNAs. Videos of salivary glands FNAs can be used for accurate diagnosis, educational and second opinion purposes,. They can also be used for archiving, teleconsultation and educational purposes, improving the performance of the already existing static telecytology stations and small cytology departments' quality indices.