Clinical decision making when cytology indicates a Warthin tumor

Warthin tumor (WT) is a benign tumor usually affecting the parotid gland. The main diagnostic tool remains ultrasound combined with fine-needle aspiration cytology (FNAC). This study aims to examine how reliably FNAC indicates WT for clinical decision making regarding surgical versus conservative management. We included all patients who underwent FNAC from a parotid gland lesion between 2016 and 2018 at our institution, and whose FNAC revealed WT suspicion. The FNACs were divided into three groups based on the cytology report: certain, likely, and possible WT. The patients were divided into two groups based on having had either surgery or follow-up. We sent a questionnaire to patients who had not undergone surgery in order to obtain follow-up for a minimum of four years. Altogether, 135 FNAC samples, from 133 tumors and 125 patients, showed signs of WT. Of the 125 patients, 44 (35%) underwent surgery, and 81 (65%) were managed conservatively. Preoperative misdiagnosis in FNAC occurred in three (7%) surgically treated tumors. Their FNACs were reported as possible WTs, but histopathology revealed another benign lesion. In the conservatively treated group, two patients underwent surgery later during the follow-up. Cytological statements of WT were seldom false, and none were malignant. The majority of the patients were only followed-up and rarely required further treatment. A certain or likely diagnosis of WT in the FNAC report by an experienced head and neck pathologist is highly reliable in selecting patients for conservative surveillance.

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.

Oncocytoid Salivary Tumors: Differential Diagnosis and Utility of Newly Described Immunohistochemistry

BACKGROUND

Oncocytoid salivary tumors include several entities such as oncocytoma, Warthin tumor, secretory carcinoma (SC), salivary duct carcinoma (SDC), acinic cell carcinoma (AciCC), oncocytic mucoepidermoid carcinoma (OMEC), intraductal carcinoma, and epithelial myoepithelial carcinoma (EMC). This review investigates the differential diagnosis of oncocytoid salivary tumors and explore the role of newly described immunostains as valuable tools for their diagnosing and potentially guiding treatment options.

METHODS

We assess the utility of incorporating new immunohistochemical markers in routine practice to aid in diagnosing oncocytoid salivary tumors and potentially provide treatment options.

RESULTS

In SDC, AR and Her2 immunostains are utilized as diagnostic tools and biomarkers for selecting patients who might benefit from Androgen-deprivation therapy (ADT) and HER2-targeted therapy. Furthermore, nuclear Pan-Trk immunostaining can aid in diagnosing SC. Additionally, NR4A3 immunostaining has been shown high sensitivity and specificity in identifying AciCC in both surgical and cytologic specimens. Similarly, RAS Q61R mutant-specific immunostaining, detected in EMC, may offer a cost-effective diagnostic marker for this tumor. Although further studies are required to evaluate the role of BSND, this marker has been reported to be positive in Warthin tumor and oncocytoma, aiding in differentiating them from other oncocytoid tumors, particularly OMEC. In addition, BRAFV600E mutant-specific immunostaining can serve as a diagnostic and potentially therapeutic marker for oncocytic intraductal carcinoma in mutation positive cases.

CONCLUSION

Oncocytoid salivary tumors may have overlapping morphologies, posing diagnostic challenges for pathologists. Recently described immunohistochemical markers may offer valuable tools for diagnosing and potentially guiding treatment options for these tumors.

Surgical management of Warthin tumor: long-term follow-up of 224 patients from 2002 to 2018

PURPOSE

Warthin tumors (WT) are the second most common benign parotid gland neoplasms. They can occur as synchronous or metachronous lesions in 6-10% of cases. This study aims to compare the complication rate in 224 patients who underwent extracapsular dissection (ECD) or superficial parotidectomy (SP) for the treatment of a WT.

METHODS

This retrospective study was conducted at the Department of Maxillo-Facial Surgery at the University of Naples "Federico II" from February 2002 to December 2018 on a group of patients who underwent surgical treatment for WT. The type of surgical technique was chosen based on Quer's classification. The complications evaluated were facial nerve palsy, hematoma, Frey's syndrome, and bleeding.

RESULTS

A total of 224 patients treated from 2002 to 2018 for Warthin tumor were included in the study. Two hundred elven had solitary tumors (94.1%) and 13 had multicentric lesions (5.8%), of which 9 cases presented synchronous lesions and 4 cases presented metachronous lesions. Extracapsular dissection (ECD) was performed in 130 patients (58.3% of cases) and superficial parotidectomy (SP) in the other 94 (41.7% of cases).

CONCLUSIONS

We consider both surgical techniques as valid. In our opinion, it is essential to study each case based on Quer's Classification to obtain the best surgical outcome. Based on a lower observed rate of complications such as facial nerve palsy, Frey's syndrome, and bleeding, ECD seems to be the best option for the surgical treatment of Quer Class I lesions.

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.

Keratocystoma: A Distinctive Salivary Gland Neoplasm Characterized by RUNX2 Rearrangements

Keratocystoma is a rare salivary gland lesion that has been reported primarily in children and young adults. Because of a scarcity of reported cases, very little is known about it, including its molecular underpinnings, biological potential, and histologic spectrum. Purported to be a benign neoplasm, keratocystoma bears a striking histologic resemblance to benign lesions like metaplastic Warthin tumor on one end of the spectrum and squamous cell carcinoma on the other end. This overlap can cause diagnostic confusion, and it raises questions about the boundaries and definition of keratocystoma as an entity. This study seeks to utilize molecular tools to evaluate the pathogenesis of keratocystoma as well as its relationship with its histologic mimics. On the basis of targeted RNA sequencing (RNA-seq) results on a sentinel case, RUNX2 break-apart fluorescence in situ hybridization (FISH) was successfully performed on 4 cases diagnosed as keratocystoma, as well as 13 cases originally diagnosed as tumors that morphologically resemble keratocystoma: 6 primary squamous cell carcinomas, 3 metaplastic/dysplastic Warthin tumors, 2 atypical squamous cysts, 1 proliferating trichilemmal tumor, and 1 cystadenoma. RNA-seq and/or reverse transcriptase-PCR were attempted on all FISH-positive cases. Seven cases were positive for RUNX2 rearrangement, including 3 of 4 tumors originally called keratocystoma, 2 of 2 called atypical squamous cyst, 1 of 1 called proliferating trichilemmal tumor, and 1 of 6 called squamous cell carcinoma. RNA-seq and/or reverse transcriptase-PCR identified IRF2BP2::RUNX2 in 6 of 7 cases; for the remaining case, the partner remains unknown. The cases positive for RUNX2 rearrangement arose in the parotid glands of 4 females and 3 males, ranging from 8 to 63 years old (mean, 25.4 years; median, 15 years). The RUNX2 -rearranged cases had a consistent histologic appearance: variably sized cysts lined by keratinizing squamous epithelium, plus scattered irregular squamous nests, with essentially no cellular atypia or mitotic activity. The background was fibrotic, often with patchy chronic inflammation and/or giant cell reaction. One case originally called squamous cell carcinoma was virtually identical to the other cases, except for a single focus of small nerve invasion. The FISH-negative case that was originally called keratocystoma had focal cuboidal and mucinous epithelium, which was not found in any FISH-positive cases. The tumors with RUNX2 rearrangement were all treated with surgery only, and for the 5 patients with follow-up, there were no recurrences or metastases (1 to 120 months), even for the case with perineural invasion. Our findings solidify that keratocystoma is a cystic neoplastic entity, one which appears to consistently harbor RUNX2 rearrangements, particularly IRF2BP2::RUNX2 . Having a diagnostic genetic marker now allows for a complete understanding of this rare tumor. They arise in the parotid gland and affect a wide age range. Keratocystoma has a consistent morphologic appearance, which includes large squamous-lined cysts that mimic benign processes like metaplastic Warthin tumor and also small, irregular nests that mimic squamous cell carcinoma. Indeed, RUNX2 analysis has considerable promise for resolving these differential diagnoses. Given that one RUNX2 -rearranged tumor had focal perineural invasion, it is unclear whether that finding is within the spectrum of keratocystoma or whether it could represent malignant transformation. Most important, all RUNX2 -rearranged cases behaved in a benign manner.

Differentiation of parotid pleomorphic adenoma from Warthin tumor using signal intensity ratios on fat-suppressed T2-weighted magnetic resonance imaging

OBJECTIVE

To investigate the value of magnetic resonance imaging (MRI) signal intensity ratios (SIRs) based on fat-suppressed T2-weighted imaging (FS-T2WI), together with demographic features, MRI anatomical characteristics, and SIRs of histopathological patterns of the tumors, in the differentiation of parotid pleomorphic adenoma (PA) from Warthin tumor (WT).

STUDY DESIGN

In total, 90 patients with PA and 56 patients with WT were enrolled in the study. SIRs of tumor to normal parotid gland (SIR-T/P), spinal cord (SIR-T/S), and muscle (SIR-T/M) were calculated. Demographic and radiological features of the 2-patient groups were compared with univariate analysis and multivariate logistic regression analysis. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed to evaluate the utility of SIRs in distinguishing between PA and WT.

RESULTS

SIR-T/P exhibited outstanding discriminating ability (AUC = 0.934), SIR-T/S had excellent discrimination (AUC = 0.839), and SIR-T/M showed acceptable discrimination (AUC = 0.728). When SIR-T/P of 1.96 was selected as the cutoff value, sensitivity and specificity were 0.756 and 0.982, respectively. SIR-T/P, age, sex, and number of lesions were identified as independent predictors by multivariate logistic regression analysis. Differences in SIRs between histopathological patterns were significant.

CONCLUSION

SIR-T/P based on FS-T2WI is an effective discriminator in the differential diagnosis between PA and WT. Age, sex, and number of lesions provided additional value in differentiation.

A Safety and Feasibility Trial of Ultrasound-Guided Radiofrequency Ablation of Parotid Warthin's Tumor

OBJECTIVE

To determine if ultrasound-guided (USG) radiofrequency ablation (RFA) of Parotid Warthin's tumor under local anesthesia is a safe and effective procedure.

STUDY DESIGN

Safety and feasibility study.

SETTING

Tertiary academic medical center.

METHODS

This is an IDEAL phase 2a trial in a tertiary referral center. Twenty patients with Parotid Warthin's tumor were recruited. RFA was done between September and December 2021 for all 20 patients using a CoATherm AK-F200 machine with a disposable, 18G × 7 mm radiofrequency electrode. Results and follow-up statistics were compared with a historic sample of patients with parotid Warthin's tumor who underwent parotidectomy between 2019 and 2021 in the same center.

RESULTS

Nineteen patients were included in the analysis as 1 patient dropped out after 4 weeks of follow-up. The mean age for the RFA group was 67 years old with most of them being male smokers. At a median of 45 weeks (44-47 weeks) postprocedure there was a 7.48 mL (68.4%) volume reduction compared to baseline. Three patients had transient facial nerve (FN) paresis, 1 recovered within hours, and the other 2 by 12 weeks follow-up. Three patients had great auricular nerve numbness; 1 patient had infected hematoma treated in an out-patient manner. Compared to a historic cohort of parotidectomy patients for Warthin's tumor, there was no significant difference in FN paresis and other minor complications between the 2 treatment modalities.

CONCLUSION

The current analysis suggests that USG RFA of Warthin's Tumor is a safe alternative to parotidectomy with shorter operative time and length of stay.

Salivary Duct Carcinoma Arising in a Warthin Tumor of the Parotid Gland: A Rare Case Report with Review of Literature and PD-L1 Expression

Warthin's tumor is the second most common neoplasm of the parotid gland and consists of 2 components, including lymphoid stroma and glandular epithelium. Malignant transformation in this tumor is mostly seen in the lymphoid component; however, the carcinomatous transformation of the epithelial component is extremely rare. Cases of latter reported in the literature include squamous cell carcinoma, adenocarcinoma, mucoepidermoid carcinoma, oncocytic carcinoma, Merkel cell carcinoma, and undifferentiated carcinoma. We describe an extremely rare case of salivary duct carcinoma arising in a Warthin tumor in a 64-year-old male. Patient presented with an enlarging left parotid mass, biopsy of which showed salivary duct carcinoma. He subsequently underwent left parotidectomy along with left level II-IV lymph node dissection. Histology revealed both in situ as well as invasive salivary duct carcinoma arising from Warthin tumor. Immunohistochemistry showed tumor cells positive for CK7, AR, and GATA3, while p63 highlighted the myoepithelial cell layer in the in situ component. Her2 was 2+ by immunohistochemistry. In addition, PD-L1 IHC revealed positive expression with a combined positive score of 20%.

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 of the Parotid Gland: The History of an Eponym

The eponymous history of Warthin tumor (WT) is a fascinating issue in the field of salivary gland pathology. The late decades of the nineteenth century and the turn of the century saw notable German and French contributions on WT. Especially, the seminal 1910 paper of Albrecht and Arzt of Vienna is the foundation for the current knowledge of WT. It is generally believed that prior to this pioneering study, Hildebrand of Göttingen accurately described the lesion of WT in 1895. However, the historical origins of WT appear to be unsettled, and only a few German pathologists and surgeons are aware that dating back to 1885, the first recognizable reference to WT was that by the renowned German-Swiss pathologist Zahn, whose name is eponymously associated with "Zahn infarct" and "lines of Zahn". Two noted French surgeons with a major interest in pathology, Albarrán in 1885 and Lecéne in 1908, did not contribute to the topic. Since the 1950s, a mostly American group of pathologists and surgeons gradually adopted the term WT to replace the very accurate histologic descriptor "papillary cystadenoma lymphomatosum" coined by Warthin himself in 1929. It is our opinion that from a historical viewpoint, there is no particular reason why this tumor should have been named WT.

Validation of indications for enucleation for benign parotid gland tumors

BACKGROUND

Enucleation has been reported as a minimally invasive surgery for Warthin's tumor (WT). However, the definite indications for enucleation have not been clarified.

METHODS

Enucleation was indicated by the following findings: findings of WT, cystic fluid, or benign leukocytes by fine-needle aspiration cytology; a well-margined and homogeneous pattern on imaging; and a tumor location in the tail or preauricular area of the parotid gland. We reviewed 552 cases treated with parotid gland surgery in our hospital.

RESULTS

A total of 108 tumors were treated with enucleation and included no malignant solid tumors or pleomorphic adenoma. Enucleation demonstrated low invasiveness and complication rates. Revision surgery for WT reappearance after enucleation was rare and showed minimal scarring, with a lower risk of facial weakness.

CONCLUSIONS

The indication criteria for enucleation were validated. Such enucleation is useful, as it is associated with minimal invasiveness, low complication rates, and safety in revision surgery.

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.

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.

Cutaneous Lymphadenoma Is a Distinct Trichoblastoma-like Lymphoepithelial Tumor With Diffuse Androgen Receptor Immunoreactivity, Notch1 Ligand in Reed-Sternberg-like Cells, and Common EGFR Somatic Mutations

The term "cutaneous lymphadenoma" was coined in this journal for an unusual lymphoepithelial cutaneous adnexal neoplasm, possibly with immature pilosebaceous differentiation. Some authors further proposed that cutaneous lymphadenoma was an adamantinoid trichoblastoma. However, although a hair follicle differentiation is widely accepted, the fact that this is a lymphoepithelial tumor is not appropriately explained by the trichoblastoma hypothesis. Our goal was to further clarify the phenotypic and genotypic features of cutaneous lymphadenoma in a series of 11 cases. Histologically, a lobular architecture surrounded by a dense fibrous stroma was present in all cases. The lobules were composed of epithelial cells admixtured with small lymphocytes and isolated or clustered large Reed-Sternberg-like (RS-L) cells. The epithelial cells were diffusely positive for the hair follicle stem cell markers CK15, PHLDA1, and for androgen receptor. No immunostaining for markers of sebaceous differentiation was found. Intraepithelial lymphocytes were predominantly CD3+, CD4+, FoxP3+ T cells. RS-L cells showed both strong Jagged-1 and Notch1 cytoplasmic immunostaining. Androgen-regulated NKX3.1 nuclear immunostaining was present in a subset of large intralobular cells in all cases. Double immunostaining showed coexpression of NKX3.1 and CD30 in a subset of RS-L cells. No immunostaining for lymphocytic or epithelial markers was present in RS-L cells. EGFR, PIK3CA, and FGFR3 somatic mutations were found by next-generation sequencing in 56% of the cases. We consider that cutaneous lymphadenoma is a distinct benign lymphoepithelial tumor with androgen receptor and hair follicle bulge stem cell marker expression, RS-L cell-derived Notch1 ligand, and common EGFR gene mutations.

Experience with follow-up strategy in selected patients with Warthin tumour diagnosed by ultrasound-guided fine-needle aspiration biopsy (FNAB)

PURPOSE

Warthin tumour (WT) management options comprise surgery or follow-up. The purpose of this study was to asses our experience with the follow-up strategy in selected patients with an ultrasound-guided fine-needle aspiration biopsy (FNAB) showing WT.

METHODS

We performed a retrospective analysis of patients diagnosed with WT using FNAB between 1.1.2006 and 31.12.2019. Patients were divided into three groups according to the therapeutic approach-immediate surgery, follow-up or surgery and follow-up.

RESULTS

323 patients were diagnosed with WT and met the study's inclusion criteria (154 women, 47.7% and 169 men, 52.3%). 192 patients were operated right after the diagnosis, 109 patients were observed with their first detected tumour and 22 patients had parotid WT surgery and were in the wait-and-scan protocol with a contralateral tumour, recurrence or both. The growth rate (GR) of observed WT was highly variable (mean GR 1.0 mm/year (5%), median GR 0.8 mm (9%), range - 19.7 to +20.0 mm/year). From 131 patients in the follow-up group, 19 patients underwent surgery and definitive histology revealed 17 WTs and 2 adenocarcinomas. However, these 2 patients had changes in sonographic findings at their next control. The mean observation time was 44.7 months (range 12-138 months) in patients followed exclusively at our institution and 50.9 months (range 12-110 months) in patients observed in cooperation with an otorhinolaryngologist at the patients' place of residence.

CONCLUSION

Ultrasound-guided FNAB is an accurate and simple method in WT diagnosis and based on its result a follow-up strategy can be chosen for selected patients with WT.

Conventional, diffusion, and dynamic contrast-enhanced MRI findings for differentiating metaplastic Warthin's tumor of the parotid gland

The purpose of this study was to explore conventional, diffusion, and dynamic contrast-enhanced MRI (DCE-MRI) characteristics for differentiating metaplastic Warthin's tumor (MWT) from other tumor types of the parotid gland, including non-metaplastic Warthin's tumor (non-MWT), pleomorphic adenoma (PA), and malignant tumor (MT). A total of 178 patients with histologically proven tumors of the parotid gland, including 21 MWTs, 49 non-MWTs, 66 PAs, and 42 MTs, were enrolled in the study. Conventional MRI was performed in all patients. One hundred and fifty patients had preoperative diffusion-weighted MR imaging (DWI), and 62 patients had preoperative DCE-MRI. The differences in the conventional, DCE-MRI, and DWI records between MWTs and the other three tumor types were statistically evaluated. Compared with non-MWTs and PAs, there was a statistically significant difference in circumscription (p < 0.01). The ill-defined circumscription was more common in MWTs than non-MWTs and PAs. Compared with PAs, there was a statistically significant difference in morphology (p < 0.05). The lobulated morphology was more common in PAs than MWTs. Compared with PAs and MTs, there was a statistically significant difference in the T2 signal of the solid component (p < 0.01). The T2 moderate intensity of solid components was more common in MWTs than PAs and MTs. The solid components of PAs mostly showed hyperintense on T2-weighted imaging. Cyst/necrosis was more common in MWTs than PAs and MTs. Hyperintense of cyst/necrosis was more common in MWTs and non-MWTs. With respect to contrast enhancement, 52.4% MWTs exhibited moderate or marked enhancement, and most non-MWTs (81.6%) exhibited mild enhancement. Most PAs (84.8%) exhibited marked enhancement. The mean ADC value of MWTs (0.94 × 10-3 ± 0.11 mm2/s) was significantly lower than that of the PAs (1.60 × 10-3 ± 0.17 mm2/s) (p < 0.001). On DCE-MRI, six of eight MWTs demonstrated TIC of type B. Although MWT is rare, conventional MRI characteristics, DWI and DCE-MRI can provide useful information for differentiating MWT from other parotid mass.

The potential role of follicular helper T cells and helper T cells type 1 in Warthin tumour

Warthin tumour (WT) is a benign tumour of the salivary gland that proliferates in both glandular epithelial and lymphoid tissue components, and rarely exhibits cystic changes. T follicular helper cells (Tfh) are involved in the formation and maintenance of germinal centres, the differentiation of B cells into plasma cells, and the maintenance of helper T cell type 2 (Th2)-dominant humoral immune responses. T-bet induces differentiation into helper T cell type 1 (Th1) by suppressing differentiation into Tfh and enhances cellular immune responses. The objective of this study was to enhance our understanding of the immune responses and relationship between Tfh and Th1 cells in patients with WTs. In this study, we classified WTs (n = 64) into solid-type (n = 25) and cyst-type (n = 39). We also performed immunostaining of the Tfh markers CXCR5 and CD40 L, and the Th1 marker T-bet for statistical analysis. The cyst-type exhibited significant atrophy of the germinal centre area (P = 0.0019), significantly fewer Tfh-positive lymphocytes in germinal centres (P < 0.0001), and significantly more T-bet-positive lymphocytes in the epithelium (P = 0.0017). We observed that Tfh were involved in the formation and maintenance of lymphoid follicles in WTs. In the cyst-type, Th2-dominant humoral immune responses were suppressed, and Th1-dominant cellular immune responses may have caused damage to tumour tissue.

Clinical Utility of Qualitative Elastography Using Acoustic Radiation Force Impulse for Differentiating Benign from Malignant Salivary Gland Tumors

The goal of the work described here was to evaluate the utility of acoustic radiation force impulse (ARFI) imaging, a novel elastography technique, for differentiating benign from malignant salivary gland tumors. With the use of conventional strain elastography (SE) and ARFI imaging with a four-pattern scoring system, 185 tumors were examined (163 benign/22 malignant). When a score of ≥3 was used to define malignancy, the sensitivity, specificity and accuracy were higher for ARFI imaging (77.3%, 63.8% and 65.4%, respectively) than for conventional SE (54.5%, 56.4% and 56.2%, respectively). ARFI imaging findings revealed that most (92%) Warthin tumors, but only 24% of pleomorphic adenomas, were benign (score: 1 or 2). Attenuation of acoustic push pulses made it difficult to determine the stiffness of malignant tumors in the deep parotid lobes. Thus, ARFI imaging is a useful tool for screening Warthin tumors and exhibits high sensitivity for malignant tumors of salivary glands, other than deep parotid lobe tumors.

Functional outcomes after extracapsular dissection with partial facial nerve dissection for small and large parotid neoplasms

PURPOSE

Multiple surgical options exist for benign parotid tumors without agreement upon a single, best approach. We evaluated the short-term outcomes and rate of complications using the ECD-FND technique for small and large parotid neoplasms involving the superficial and deep lobes of the parotid gland using a categorical approach.

MATERIAL AND METHODS

A single surgeon retrospective cohort study with analysis of patient demographics, outcomes, and complication rates was conducted of patients undergoing the ECD-FND for benign parotid neoplasm. Cases from May 2014 to May 2020 with at least 6 months follow up were considered. Complications were assessed by chart review and tumors were categorized by size and by European Salivary Gland Society (ESGS) classification assigned by a neuroradiologist.

RESULTS

Fifty-one patients who underwent ECD-FND of suspected benign parotid mass met inclusion criteria. The most common histology was pleomorphic adenoma (56.9%) followed by Warthin's tumor (19.6%). Overall rate of complications was 31.4% with no major complications. Most patients (88.2%) had normal facial nerve function immediately after surgery and all recovered completely in the post operative period. Sialocele occurred in 15.7% of patients with 87.5% resolved within one month and seromas occurred in four patients (7.8%). There was no significant difference in complication rates between the size of tumor (p = 0.889), depth (p = 0.770), or ESGS classification (p = 0.846).

CONCLUSIONS

The ECD-FND technique achieved excellent facial nerve outcomes among our cohort, which included a - proportion of large (>3 cm) and deep lobe tumors. Complications rates and outcomes were similar for larger and deep lobe tumors that underwent a ECD-FND approach.

LEVEL OF EVIDENCE

3.

Juvenile sclerosing polycystic adenosis cytologically mimicking Warthin tumor

Sclerosing polycystic adenosis (SPA) is a rare salivary gland disease. Histologically it resembles a low-grade ductal carcinoma in situ or sclerosing adenosis of the breast, characterized by lobular proliferation of ducts with apocrine cellular features surrounded by fibrosclerotic stroma. Although SPA is typically benign, recurrence is not uncommon, and cases with a malignant component have been documented. Thus, complete excision is desirable but preoperative diagnosis is challenging. A 12-year-old boy presented with a painless mass in the right neck. We identified a well-demarcated mass in the right parotid region measuring approximately 2 cm using cervical echography and magnetic resonance (MR) imaging. Fine-needle aspiration (FNA) revealed two cell types. There were loosely cohesive clusters of polymorphic epithelioid cells with irregular nuclei and abundant vacuolated cytoplasm containing zymogen granules. Some of these cells were binuclear. The other cell types represented normal ductal cells. The original cytological diagnosis was Warthin tumor. Right parotidectomy was performed. Histologically, we observed proliferation of ducts with granular, vacuolated, zymogen granules, and apocrine-like features in the cytoplasm with hyalinizing sclerotic stroma and some binuclear cells. Four years after parotidectomy, there has been no recurrence or malignant transformation.Cytological diagnosis of SPA is challenging on FNA specimens since SPA is a very rare entity of the salivary gland that can mimic other salivary gland neoplasms. A mixture of apocrine-like cells and sebaceous-like cells, nuclear pleomorphism, and zymogen granules can help to diagnose this rare lesion during the initial cytological diagnosis.

The growth rate and the positive prediction of needle biopsy of clinically diagnosed Warthin's tumor

PURPOSE

This study reports the clinical course, including the growth rate, of Warthin's tumor (WT) and evaluates the positive prediction of needle biopsy for WT.

METHODS

The medical records of 182 patients clinically diagnosed with WT were retrospectively reviewed. Tumor growth rates were measured in patients who underwent serial radiologic exams with minimum 6-month time intervals, and the positive prediction value (PPV) of needle biopsy was evaluated in comparison with surgical pathology in patients who underwent surgical excision of the tumors.

RESULTS

Serial radiologic exams were available for growth rate measurement in 31 tumors (size 0.7-9.1 cm) from 25 patients. Among these, 24 tumors increased in size, and 7 were stable. The median follow-up duration was 23.5 months [interquartile range (IQR) 14.8-51.9], and the tumor growth rate ranged from - 0.36 to 2.26 cm per year (median 0.26, IQR 0.07-0.44). Needle biopsy results were available for comparison with postoperative pathology specimens in 147 patients. The PPV was 97.7% for fine-needle aspiration biopsy and 100% for core-needle biopsy. There were no reports of inflammation, facial nerve paralysis, or admission event during the follow-up.

CONCLUSIONS

WT glows slowly and can be predicted by needle biopsy. Therefore, parotid masses diagnosed as Warthin's tumor can be treated or left untreated based on the patient's needs and clinical decision-making.

Clinical and sonographic characteristics of Warthin-like variant papillary thyroid carcinomas

AIM

To summarize the clinical, ultrasonographic (US) and pathological characteristics of Warthin-like variant papillary thyroid carcinomas (WVPTC).

MATERIAL AND METHODS

Medical records and US images of 32 cases of WVPTCs diagnosed between December, 2006 and September, 2018 were reviewed. Clinical, pathological and US characteristics of these cases were collected and summarized. ACR TI-RADS was followed during the analysis of the US features of the lesions. Results: Totally, 32 patients with 33 WVPTC nodules were reviewed. WVPTC was more often seen in female patients (27/32,84.4%) with a relatively high age (mean age, 51.0±10.8 years old). Hyperthyroidism was observed in 14 patients; 2 patients were diagnosed as subclinical hyperthyroidism and 1 patient as subclinical hypothyroidism. Abnormal thyroglobulin antibody was detected in 22 patients. Mean size of the nodule was 1.2±0.5 cm (range, 0.5~2.99 cm) on US. Pathologically, tumor margin of 63.6% carcinomas were infiltrative but most (72.9%) of the enrolled carcinomas were intra-thyroidal. Lymphocytic thyroiditis was detected in 87.5% (28/32) patients. On US, most WVPTCs were solid or almost complete solid (32/33, 97.0%) and very hypoechoic (26/33, 78.8%). Taller-than-wide shape (6/33, 18.2%) and punctate echogenic foci (9/33, 27.3%) were not popular. All the nodules were scored higher than 5 points according to the ACR TI-RADS, including 9 nodules that were classified into TR4 and 24 nodules as TR5. Follow-up information was available in 31 patients and no recurrence or distal metastasis was detected.

CONCLUSIONS

WVPTC is a rare variant of PTCs with favorable outcomes. Very hypoechoic echogenicity, solid or almost complete solid composition are the vital indicators for biopsy, even though the nodule may be wider-than-tall and have a lack of punctuate echoic foci.

Synchronous Warthin tumor and papillary oncocytic cystadenoma in the ipsilateral parotid gland: an unreported association

The occurrence of ipsilateral, synchronous, primary salivary gland tumors of different histological type is rare. In this report, we present the case of a 52-year-old male, established smoker, who showed simultaneously two different benign tumors in the right parotid gland. The patient complained of swelling below the angle of the mandible. Ultrasonography and computed tomography imaging revealed one mass of about 2.8 cm in the right gland. Besides, one small nodule in the left parotid gland was observed. The cytological diagnosis of the right gland was benign tumor, type IVa of the Milan system, consistent with Warthin tumor (WT). The clinical diagnosis was bilateral parotid WT. The histopathological (HP) study of the surgical specimen revealed a WT in combination with a papillary oncocytic cystadenoma (POC) in the right parotid. To our knowledge, this combination of tumors has not been previously reported. In our case, the association of tumors was not detected by imaging or fine-needle aspiration cytology (FNAC). WT and POC are difficult to distinguish by FNAC because their epithelial component is very similar. POC can resemble WT without lymphoid stroma, but the totality of HP features allows the differentiation of both processes. These tumors can be related to a common causal determinant and should not be considered as a result of chance. Both tumors follow favorable courses and are curable by surgical resection.

Risk interrelationship among multiple primary tumors: A case report and review of literature

RATIONALE

Along with advanced management in oncology, great progress has been recently achieved in the studies of multiple primary tumors. Several reports have studied the coexistence between lymphoma and either renal cell carcinoma (RCC) or Warthin tumor. However, the level of coexistence between these cases remains unclear due to the absence of a distinct link between them.

PATIENT CONCERNS

We present a unique case of multiple primary tumors (lymphoma, RCC, and Warthin tumor) in an 80-year-old man and a review of the literature on the coexistence of RCC with lymphoma and lymphoma with Warthin tumor.

DIAGNOSIS

With a history of RCC, the patient had a freely movable lump under his left ear, and the pathological report indicated Hodgkin lymphoma and Warthin tumor.

INTERVENTION

RCC and Warthin tumor of the patient were surgically treated, followed by 2 cycles (14 days per cycle) of Epirubicin 40 mg day 1, Bleomycin 8 mg day 1, Vincristine 2 mg day 1, and Dacarbazine 500 mg day 1. The chemotherapy protocol was then changed to Epirubicin 40 mg day 1, Vincristine 2 mg day 1, and Dacarbazine 500 mg day 1 for 7 cycles.

OUTCOMES

After the last day of chemotherapy, the patient showed a complete response.

LESSONS

To the best of our knowledge, this paper is the first to report a case of multiple primary tumors with a complete response. For their early detection, favorable prognosis, and correlation identification, we suggest a transitive relation between these coexisting tumors. Therefore, similar studies should be conducted.

Warthin-like papillary thyroid carcinoma with immunoglobulin G4-positive plasma cells possibly related to Hashimoto's thyroiditis

Hashimoto's thyroiditis with heavy lymphoplasmacytic infiltration is a common comorbidity of immunoglobulin G4 (IgG4)-related thyroiditis and Warthin-like papillary thyroid carcinoma (WL-PTC). We hypothesized that WL-PTC may have a strong association with IgG4-related thyroiditis. To validate this hypothesis, we clinically and immunohistochemically studied 17 WL-PTC cases. Fourteen patients (82.4%) had anti-thyroglobulin antibody and were confirmed to have Hashimoto's thyroiditis through microscopic analysis. Among them, five (29.4%) had disease consistent with IgG4-related thyroiditis but did not exhibit a "storiform" pattern or obliterative phlebitis. IgG4-related diseases were not found in other organs. No cases with serum IgG4 level of >135 mg/dL were noted. A total of 94.1% of WL-PTC cases had IgG4-positive plasma cells (⁺PCs) in the stroma, and cases with rich IgG4⁺PCs were more frequently associated with Hashimoto's thyroiditis than those with poor IgG4⁺PCs. In this study, all three cases without Hashimoto's thyroiditis had poor IgG4⁺PCs, and one of them did not exhibit IgG4⁺PCs in the stroma of WL-PTC and Hashimoto's thyroiditis. Nodal metastatic lesions were seen in eight cases, all of which were not WL-PTC. As such, we should consider that the Hashimoto's disease with rich IgG4⁺PCs seen in our cases is representative of non-IgG4-related disease and not IgG4-related disease involving multiple organs. This study is the first to demonstrate the presence of IgG4⁺PCs in the stroma of WL-PTC. We concluded that the appearance of IgG4⁺PCs in the stroma of WL-PTC may be related to Hashimoto's thyroiditis with rich IgG4⁺PC.

[Retrospective analysis of 896 cases of parotid gland tumor]

PURPOSE

To review the clinical data of patients undergoing operation, in order to summarize the incidence, proportion, clinical examination and diagnostic methods of parotid tumors.

METHODS

Eight hundred and ninty-six cases of parotid gland tumors were collected from 2008 January to 2015 July from department of oral and maxillofacial surgery in Shengjing Hospital of China Medical University. A retrospective study of the clinical data was carried out, including age, gender, tumor location, diagnostic methods and pathological results.

RESULTS

In 896 patients with parotid gland tumor, 432 were male, 464 were female, the ratio was 1:1.07; 431 cases were on the left side, 454 cases were on the right side, 11 cases were bilateral; The proportion of parotid tumor was higher in patients aged 31 to 70 years old. 786 cases were benign, 110 cases were malignant, the ratio of benign to malignant was 7.15:1. Pleomorphic adenoma, Warthin tumor and basal cell adenoma were the most common types of benign tumors, while mucoepidermoid carcinoma, acinic cell carcinoma and adenoid cystic carcinoma accounted for the most of malignant tumors.

CONCLUSIONS

The pathological types of parotid gland tumor are complicated. Clinical examination and imaging features are helpful to diagnosis. The accuracy is high in diagnosis of parotid gland tumor by frozen section, which is useful to assist making treatment plan.

Incidental finding of upper lip Warthin tumor

AIM

This report shows an incidental finding of Warthin tumor in upper lip mucosa during hospitalization for a biting lesion of cheek mucosa MATERIALS AND METHODS: A 32-year-old male affected by a biting lesion of cheek mucosa was presented at Maxillo- Facial Unit of Federico II University. Clinical examination showed as an incidental finding a solid mass in the superficial layer of upper lip mucosa. We performed mini-invasive surgical treatment to obtain a radical excision of the cheek lesion at the same time as excision of Warthin tumor.

RESULTS

a follow up of 12 months was performed. The complete healing of the two wounds was achieved, with no recurrence of any of the pathologies.

DISCUSSION

The location of this Warthin tumor of minor salivary glands is very unusual. The role of imaging in diagnosis of Warthin tumor of minor salivary glands is to define localization, shape and dimension, contour, malignant features, nodal involvement. The role of fine needle aspiration cytology (FNAC) is critical in the diagnosis and therapy of minor salivary gland tumors. The surgical treatment in patients affected by Warthin tumour of minor salivary glands is local excision with a wide tumor free margin to prevent potential recurrence.

CONCLUSIONS

Warthin tumor of minor salivary glands is a rare disease. We report a singular case of Warthin tumor localized in the upper lip mucosa, found as an incidental finding during a recovery for a biting lesion of cheek mucosa.

KEY WORDS

Incidental finding, Minor salivary glands, Warthin tumor.

Immunohistochemical Staining of Histological Fragments Derived from Salivary Gland Tumour Fine-Needle Biopsy Aspirates

OBJECTIVES

The aim of this study was to describe a method for analysing histological fragments derived from fine- needle aspirate biopsy (FNAB) of salivary gland tumours (SGTs), and to evaluate the use of immunohistochemistry (IHC) on them.

STUDY DESIGN

We reviewed all 509 FNAB pathology reports taken from SGTs at Helsinki University Hospital, Finland, between 1999 and 2009. In 51% of the cases (n = 209) "histo-fragments" had been obtained and 31 had been further analysed by IHC. Of these, 25 (81%) were available for review. We evaluated the benefit of IHC by relating its added value to the preoperative cytological diagnosis and its accuracy compared with the postoperative histological diagnosis.

RESULTS

Most of the samples analysed by IHC were assigned a malignant diagnosis, with 12 different types of malignancy represented. IHC was advantageous in 76% of the cases. In the 108 studies using IHC in this series, antibodies to 36 different antigens were used.

CONCLUSION

Analysis of histo-fragments in FNABs using IHC can be valuable in specific differential diagnostics and raises diagnostic accuracy in SGTs.

p63 Expression in Salivary Gland Tumors: Role ofΔNp73L in Neoplastic Transformation

To illustrate the role of p63 and its truncated variants in salivary gland tumors, 23 consecutive tumors and 6 normal salivary glands were studied immunohistochemically with anti-p63 antibody and by reverse transcriptase (RT) and nested polymerase chain reaction (PCR) to detect p63 isoform expression. Normal salivary glands: p63 antibody-stained basal and myoepithelial cells; by RT and nested PCR, the 2 main isoforms were present, whereas ΔNp73L was absent. Tumors: p63 antibody was positive in the following: Warthin tumor (WT) (3/3), oncocytoma (OC) (1/1), pleomorphic adenoma (PA) (7/7), polymorphous-low-grade adenocarcinoma (PLGA) (3/3), adenoid-cystic carcinoma (ADCC)(3/4), epithelial-myoepithelial-cell carcinoma (EMC) (1/1), and myoepithelial-cell carcinoma (MCC) (1/1). By RT and nested PCR all tumors expressed p63 irrespective of their morphologic differentiation. The ΔNp73L isoform was present in tumoral tissue but absent in normal salivary gland. These data suggest that p63, particularly its splice variant ΔNp73L, is involved in the neoplastic transformation of salivary glands.

Local Excision Procedure for Warthin's Tumor of the Parotid Gland

The aim of this work is to establish a local excision procedure (LEP) and indications of this procedure for Warthin's tumor. Seventy-three patients (82 sides) with Warthin's tumor were studied. Point I was located 1 cm from the intertragal notch in the direction indicated by the notch. Point S was located 5 mm superior to the inferior end of the mandibular angle. The trunk of the facial nerve and the marginal mandibular branch run at the points I and S, respectively. In surgical maneuvers below the I-S line, the marginal mandibular and colli branches may exist within the surgical field, but the trunk and other peripheral branches of the facial nerve will not be encountered. For Warthin's tumor estimated to be below the I-S line (Group A), LEP was used, involving resection of the tumor after locating and dissecting the marginal mandibular and colli branches. For tumors not meeting these criteria (Group B), partial superficial parotidectomy was performed. Results indicated that mean volume of hemorrhage was significantly smaller, and that mean operation time was significantly shorter in Group A than in Group B. Conversely, no significant difference in tumor size or incidence of postoperative facial paresis was identified between the 2 groups. Recurrence has not yet been noted in either group. In conclusion, LEP is useful for Warthin's tumor below the I-S line. This procedure seems applicable not only to Warthin's tumors, but also to other benign parotid tumors in the surgical field below the I-S line, such as pleomorphic adenoma and lymphoepithelial cyst.

Ultrasonographic features and clinical characteristics of Warthin-like variant of papillary thyroid carcinoma

Warthin-like variant of papillary thyroid carcinoma (WVPTC) is a rare entity recently characterized. We evaluated ultrasonographic (US) features and clinical characteristics of WVPTC. Nine patients were diagnosed with WVPTC through surgery in our institution from May 2005 to January 2015. Eight of nine patients had available preoperative US images. A retrospective review of the US and clinical characteristics was performed. WVPTC compromised of 0.06% of 14,071 PTCs surgically confirmed. A mean age of nine patients was 53.2 years (range, 32-75 years). The mean nodule size of nine WVPTCs was 0.9 cm (range, 0.5-1.5 cm). Two patients showed central nodal metastasis and one patient with conventional PTC as an index tumor underwent central and lateral neck dissection. No one showed recurrence or distant metastasis during the follow-up period (mean, 4.6 years; range, 0.6-10 years). The most common US features of WVPTCs were solid composition (62.5%), hypoechogenicity (75%), and wider-than-tall shape (100%), respectively. Four (50%) of eight nodules showed well-defined margin and three (37.5%) of them had cystic component. One of eight resembled focal thyroiditis. Three nodules were considered as probably benign with US. All nine cases demonstrated underlying heterogeneous parenchymal echogenicity and accompanied chronic lymphocytic thyroiditis in permanent sections. Thyroid function tests in all patients were normal except for one with subclinical hypothyroidism. WVPTC is an uncommon subtype of PTC and has favorable prognosis, which can be misdiagnosed as a probably benign nodule or focal thyroiditis with US. All cases are associated with heterogeneous parenchyma in the background.

If cytology of Warthin tumor is accurate, can management be conservative?

We conducted a retrospective study to assess the accuracy of fine-needle aspiration cytology (FNAC) in the diagnosis of Warthin tumor and to evaluate the subsequent risk of conservative nonsurgical management. We reviewed the records of 75 patients (76 tumors) with a parotid mass that had been diagnosed as a Warthin tumor by FNAC. This patient population was made up of 64 men and 11 women, aged 46 to 93 years (mean: 67). Of the 76 tumors, 40 were treated with surgical excision and 36 with conservative measures. Histology of the 40 excised parotid masses revealed that 38 (95%) were indeed Warthin tumors, 1 (2.5%) was a low-grade adenocarcinoma, and 1 was benign-not otherwise specified. None of the 36 tumors underwent malignant transformation either clinically or on repeat FNAC (if performed) during a follow-up of 4 to 120 months (mean: 55.5 ± 32.2). We conclude that conservative management of Warthin tumors confidently diagnosed on FNAC may be an option for patients who are unwilling or unable to undergo surgical excision.

Immunohistochemical study of the epithelial and stromal components of Warthin's tumor

Warthin's tumor is a benign monomorphic adenoma with unclear origin with the highest incidence in the sixth and seventh decades. The analysis of tumor markers involved in the pathogenesis of Warthin's tumor can improve the patients' prognosis. This study included 29 cases of Warthin's tumor, which were histopathologically and immunohistochemically examined for different compartments of tumors. For immunohistochemical study, we used as specific markers for epithelial compartment CD117, CEA and AMA, respectively S100 and D2-40 for the stromal compartment. The evaluation of immunoreactions was performed by semiquantitative analysis. The analysis of the CEA, CD117 and AAM immunoexpression allowed observing various patterns of immunostaining for tumor double-layered epithelia, which has the tendency of being similar to that in the normal ductal epithelia. S100 protein positivity similar to Langerhans cells suggests that delayed hypersensitivity can be involved in tumor development. The presence of D2-40 expression in majority of tumor subcapsular vessels, similar to lymph nodes structure, confirms the hypothesis that Warthin's tumor has its origin in regional lymph nodes.

Stroma-poor Warthin's tumor with significant oncocytic hyperplasia: case presentation and considerations regarding its histogenesis

Although Warthin's tumor is one of the common tumors of the salivary glands, Warthin's tumors with a prominent component of nodular oncocytic hyperplasia reminiscent of oncocytoma are rare. Here we report such a tumor, measuring 3 cm in diameter, found in the parotid gland of an 81-year-old man. Histologically, approximately 70% of the mass was a component of nodular oncocytic proliferation, and the remaining portion was a component of conventional Warthin's tumor. We performed immunohistochemical analysis to explore what factors determined the morphogenesis of the two components in the single mass. Cytokeratin (CK) 5÷6-positive tumor cells, which represent basal cells, were aligned in a layer in the conventional Warthin's tumor component, whereas they were localized around blood vessels in the nodular oncocytic hyperplasia component. Immunostaining for CD34 showed that capillaries were sparsely present beneath the bilayered epithelia in the former component, while blood vessels resembling sinusoids separated the trabeculae of the tumor cells in the latter component. Ki-67 labeling index was slightly higher in the latter component. Double immunostaining for CK5÷6 and Ki-67 revealed that most of Ki-67-positive proliferating tumor cells were CK5÷6-positive, suggesting that CK5÷6-positive population contained proliferative progenitor cells of the tumor. These findings imply that the regional difference in the distribution pattern and proliferative activity of CK5÷6-positive putative progenitor cells along with the difference in the pattern of vascular network occurred during the tumorigenic process of the tumor and determined one region to become conventional Warthin's tumor morphology and the other to become nodular oncocytic hyperplasia.

[Parotid adenolymphoma: the enhanced MSCT manifestations and clinical pathological analysis]

OBJECTIVE

To investigate the imaging manifestations of 16-slice enhanced CT of parotid adenolymphoma in the parotid gland and the corresponding pathology,in order to improve the understanding of the CT imaging manifestations of parotid adenolymphoma in the parotid gland.

METHOD

The enhanced CT characteristics of 34 cases of parotid adenolymphoma in the parotid gland confirmed by histological pathology were retrospectively analyzed.

RESULT

There were totally 86 lesions in 34 cases, of which 12 cases with lesions in bilateral sides and 22 cases with lesions in unilateral side. Sixty-six lesions located behind and below the superficial lobe of the parotid gland. The lesions showed moderate to obvious enhancement at arterial phase, and the cystic region within the lesions showed no enhancement.

CONCLUSION

The relatively specific enhanced MSCT manifestations of parotid adenolymphoma in parotid gland include lesions located behind and below the superficial lobe of parotid gland unilaterally or bilaterally, sometimes exhibited as multiple masses, with clear edge, obvious enhancement and cystic degeneration inside.

Expression of SOX10 in Salivary Gland Oncocytic Neoplasms: A Review and a Comparative Analysis with Other Immunohistochemical Markers

OBJECTIVES

We evaluated SOX10 (SRY-related HMG-box 10) in differentiating acinic cell carcinoma (AciCC) from other salivary gland neoplasms with oncocytic features on fine-needle aspiration cell blocks (FNA CB) and compared its performance to DOG1 (discovered on gastrointestinal stromal tumor 1).

MATERIAL AND METHODS

35 FNA CB of oncocytic salivary gland neoplasms, i.e. 13 cases of AciCC, 16 of Warthin tumor (WT), 3 of mucoepidermoid carcinoma (MEC) and 3 of oncocytoma (ONC), and 75 salivary gland resections, i.e. 26 AciCC, 7 WT, 36 MEC, 3 ONC, 2 mammary analog secretory carcinomas (MASC) and 1 papillary cystadenoma were stained for SOX10 and DOG1.

RESULTS

None of the benign oncocytic neoplasms were immunoreactive for SOX10 on CB or resection, similar to DOG1. On CB, 61.5 and 77% of AciCC were positive for SOX10 and DOG1, respectively. All surgically resected AciCC cases were positive for SOX10 and DOG1; other malignant oncocytic lesions such as MEC and MASC demonstrated variable SOX10 and DOG1 staining.

CONCLUSION

The use of SOX10 may increase the diagnostic accuracy of oncocytic lesions on FNA. In this context, SOX10 is equivalent to DOG1 in ruling out benign lesions such as WT and ONC; however, negative results for SOX10 as well as DOG1 do not favor a benign diagnosis since MEC is often negative for both markers.

Demographics of benign parotid tumours: Warthin's tumour versus other benign salivary tumours

CONCLUSION

Some variation from the 'classical' clinical picture for Warthin's tumours is evident in these patients. A predilection for the parotid tail and a propensity for multiplicity has been confirmed.

OBJECTIVES

This study sought to analyse demographic and clinical features of a Warthin's patient population.

METHODS

Retrospective review of patients presenting with a benign parotid tumour. The group of Warthin's tumours was compared with the group of patients with other benign parotid tumours.

RESULTS

Of 170 primary parotid tumours, 41 (24%) were Warthin's tumour. Mean age of Warthins patients was significantly older (60 years vs 48 years, p = 0.001) and male gender more prevalent (61% vs 33%, p = 0.015) than in other benign tumours. Most (86%) Warthin's tumours were found in the parotid tail, compared with 61% of other benign tumours (p = 0.002). There was no significant ethnic predilection for Warthin's tumours. Bilaterality (30%) and multiplicity (27%) were common. Significance of gender differences disappeared with logistic regression analysis.

Occult oncocytic papillary thyroid carcinoma with lymphoid stroma (Warthin-like tumor): report of a case with concomitant mutations of BRAF V600E and V600K

Warthin-Like tumor of the thyroid is a recently described rare variant of papillary thyroid cancer. The distinct histological feature of this variant is papillary architecture lining oncocytic epithelial cells with nuclear characteristics of papillary carcinoma, accompanied by prominent lymphocytic infiltration in the papillary stalks. Here, we present a case of occult Warthin-like papillary thyroid carcinoma, 0.5-cm in maximum dimension, underwent left thyroid lobectomy in a 65 years old Chinese woman. In this case, there was no extrathyroid extension, vascular invasion and lymphatic metastasis, as well as no complication of lymphocytic thyroiditis. Immunohistochemistry staining revealed that the tumor cells were positive for Leu-M1, HBME-1, 34βE12, and MIB-1 labeling index was low. RET/PTC expression was absent in tumor cells. Furthermore, activated point mutations of BRAF V600E and V600K were concurrently detected by DNA sequencing. Further studies are needed to elucidate the prevalence and role of BRAF(V600K) mutation in papillary thyroid carcinoma, and long-term follow-up for the patient is needed to clarify the biological behavior of this variant with dual BRAF mutations.

A more appropriate clinical classification of benign parotid tumors: investigation of 425 cases

CONCLUSIONS

It is appropriate to clinically classify benign parotid tumors into three groups, i.e. superficial tumors, deep tumors, and lower pole tumors.

OBJECTIVE

It is important to classify benign parotid tumors based on location when deciding the surgical strategy and conducting clinical research. In this study, we examined a classification of benign parotid tumors that was useful for clinical practice.

METHODS

We studied 425 patients with benign parotid tumors who underwent surgery at our hospital. Their age, gender, tumor histopathology, maximum tumor diameter, postoperative facial nerve paresis, operating time, and blood loss were investigated after classifying the tumors as superficial tumors, deep tumors, or lower pole tumors. We also investigated the same parameters after dividing the lower pole tumors into superficial and deep types.

RESULTS

Lower pole tumors had distinct characteristics from superficial and deep tumors. The incidence of facial nerve paresis was significantly higher and the operating time was significantly longer for deep tumors than for either superficial or lower pole tumors, while there were no significant differences between superficial and lower pole tumors. In addition, there were no significant differences in any of the parameters between the superficial and deep types of lower pole tumor.

Epidemiology and pathology of parotid tumors five-year retrospective study

AIM

To retrospectively analyze the epidemiological, clinical and pathological data of parotid tumors.

MATERIAL AND METHODS

Reassessment of the histologic diagnosis of parotid tumor in the patients admitted to the Oral and Maxillofacial Surgery Unit of the Iasi "Sf. Spiridon" University Emergency Hospital during 2009-2013. Data on gender, age, place of residence, location, size, surgical procedure type and histopatological type were recorded.

RESULTS

The risk of developing pleomorphic adenonma is 7.40 times higher in women and 4.08 times higher before the age of 50 years. The risk of Warthin tumor is 16.47 times higher in male patients and 3.58 times higher in urban patients. People older than 50 years have a 7.14 times higher risk of developing malignancy and rural people have a 2.41 times higher risk of developing cancer. Diabetes, obesity and systemic hypertension were not important risk factors in our study.

CONCLUSIONS

According to this study age and the place of residence could be important predictors for parotid gland tumors. Since in Romania there are few epidemiological data regarding the parotid gland pathology, further cohort studies are needed for a better understanding of their clinical and pathological behavior.

Misleading appearance in cervical lymph node US diagnosis - a report on sarcoidosis, Warthin tumor and squamous cell carcinoma metastases

Ultrasonography, with its various techniques (grey-scale, color Doppler, sonoelastography) offers many signs for the differentiation between benign and malignant neck lymph nodes. In spite of recent progress, the US appearance may be misleading. We present three cases in which the ultrasonographic appearance of the lymph nodes was misleading as compared to the final diagnosis established by histopathology.

Texture-based and diffusion-weighted discrimination of parotid gland lesions on MR images at 3.0 Tesla

The purpose of this study was to evaluate whether texture-based analysis of standard MRI sequences and diffusion-weighted imaging can help in the discrimination of parotid gland masses. The MR images of 38 patients with a biopsy- or surgery-proven parotid gland mass were retrospectively analyzed. All patients were examined on the same 3.0 Tesla MR unit, with one standard protocol. The ADC (apparent diffusion coefficient) values of the tumors were measured with three regions of interest (ROIs) covering the entire tumor. Texture-based analysis was performed with the texture analysis software MaZda (version 4.7), with ROI measurements covering the entire tumor in three slices. COC (co-occurrence matrix), RUN (run-length matrix), GRA (gradient), ARM (auto-regressive model), and WAV (wavelet transform) features were calculated for all ROIs. Three subsets of 10 texture features each were used for a linear discriminant analysis (LDA) in combination with k nearest neighbor classification (k-NN). Using histology as a standard of reference, benign tumors, including subtypes, and malignant tumors were compared with regard to ADC and texture-based values, with a one-way analysis of variance with post-hoc t-tests. Significant differences were found in the mean ADC values between Warthin tumors and pleomorphic adenomas, as well as between Warthin tumors and benign lesions. Contrast-enhanced T1-weighted images contained the most relevant textural information for the discrimination between benign and malignant parotid masses, and also for the discrimination between pleomorphic adenomas and Warthin tumors. STIR images contained the least relevant texture features, particularly for the discrimination between pleomorphic adenomas and Warthin tumors. Texture analysis proved to differentiate benign from malignant lesions, as well as pleomorphic adenomas from Warthin tumors, based on standard T(1w) sequences (without and with contrast). Of all benign parotid masses, Warthin tumors had significantly lower ADC values than the other entities.

New insight into benign tumours of major salivary glands by proteomic approach

Major salivary gland tumours are uncommon neoplasms of the head and neck. The increase of precise pre-operative diagnosis is crucial for their correct management and the identification of molecular markers would surely improve the required accuracy. In this study we performed a comparative proteomic analysis of fine needle aspiration fluids of the most frequent benign neoplasms of major salivary glands, namely pleomorphic adenoma and Warthin's tumour, in order to draw their proteomic profiles and to point out their significant features. Thirty-five patients submitted to parotidectomy were included in the study, 22 were identified to have pleomorphic adenoma and 14 Warthin's tumour. Fine needle aspiration samples were processed using a two-dimensional electrophoresis/mass spectrometry-based approach. A total of 26 differentially expressed proteins were identified. Ingenuity software was used to search the biological processes to which these proteins belong and to construct potential networks. Intriguingly, all Warthin's tumour up-regulated proteins such as Ig gamma-1 chain C region, Ig kappa chain C region and Ig alpha-1 chain C region and S100A9 were correlated to immunological and inflammatory diseases, while pleomorphic adenomas such as annexin A1, annexin A4, macrophage-capping protein, apolipoprotein E and alpha crystalline B chain were associated with cell death, apoptosis and tumorigenesis, showing different features of two benign tumours. Overall, our results shed new light on the potential usefulness of a proteomic approach to study parotid tumours and in particular up regulated proteins are able to discriminate two types of benign parotid lesions.

Warthin tumor with signet-ring cell features as a pitfall in salivary gland cytopathology

BACKGROUND

Warthin tumor (WT) is a common parotid lesion reliably diagnosed by fine-needle aspiration (FNA). Worrisome metaplastic changes may occur in WT. Their interpretation as mucoepidermoid carcinoma represents a diagnostic pitfall. Moreover, WT and mucoepidermoid carcinoma may coexist, making this distinction difficult. So it is worthwhile to report unusual WT features. We describe a WT with signet-ring cells (SRCs).

CASE

A 61-year-old male presenting with a 3.6-cm right parotid gland mass underwent FNA with rapid on-site evaluation. DiffQuik-stained smears showed groups of oncocytic cells with abundant granular cytoplasm in a background rich with debris, foamy macrophages and lymphoid cells. SRCs were observed on Papanicolaou-stained smears prepared from a second pass. A WT with SRC features was diagnosed. Histology revealed a WT with post-FNA infarctual changes.

CONCLUSION

To avoid false-positive diagnoses, the cytopathologist should be aware that SRC features may occur in WT. The concomitant presence of oncocytes and SRCs is useful to correctly diagnose this unusual WT variant.

Warthin tumor in an unusual site: a case report

Warthin tumor (papillary cystadenoma lymphomatosum, adenolymphoma) is a benign neoplasm from salivary glands and is almost restricted to the parotid gland and the periparotid lymph nodes. Its etiopathogenesis has been associated with tobacco smoke. Several authors believe that the tumor develops from heterotopic salivary gland tissues or through the attraction of a heavy lymphoid reaction. Most cases involve the lower pole or the tail of the parotid. Since its description, a few cases have been reported in other sites, like the submandibular salivary gland. This study aimed to describe a rare presentation of a Warthin tumor and discuss its etiology and differential diagnosis. A 72-year-old male patient presented an asymptomatic, nodular mass adjacent to the submandibular salivary gland. Based on clinical diagnosis of cervical lymphadenopathy, the patient underwent a surgical excision of the lesion. Histopathological exam revealed a benign neoplasm from salivary glands composed of two components: epithelial and lymphoid. The findings were consistent with Warthin tumor. Warthin tumor from submandibular salivary gland is a rare lesion. Professionals should not misinterpret their site of origin, as if they were from the lower pole or the tail of the parotid.