Pleomorphic adenoma of salivary gland: to what extent does fine needle aspiration cytology reflect histopathological features?

Pathology Mimicking Orofacial Pain

A case of a 64-year-old woman is reported, who developed new-onset pain over a preexisting area of right mandibular fullness. Clinical examination, MRI, and fine-needle aspiration cytology confirmed the diagnosis of a benign parotid gland tumor-pleomorphic adenoma, which was treated by total parotidectomy with complete removal of the tumor. When evaluating a patient with orofacial pain, oral health care providers should be cognizant of all potential differential diagnoses, especially in the setting of red flags such as persistent or enlarging facial swelling/fullness.

Giant Parotid Pleomorphic Adenoma with Atypical Histological Presentation and Long-Term Recurrence-Free Follow-Up after Surgery: A Case Report and Review of the Literature

Salivary gland tumors (SGT) comprise 3% of all head and neck tumors, are mostly benign, and arise frequently in the parotid gland. Pleomorphic adenoma (PA) is the commonest SGT, representing 60-70% of all benign parotid tumors. Clinically, parotid PA presents as irregular, lobulated, asymptomatic, slow-growing preauricular mass, involving both superficial and deep lobes, and could grow to gigantic proportions. Histologically, PA has epithelial and mesenchymal elements in chondromyxoid matrix and is managed surgically. Based on a review of 43 cases reported in English literature since 1995, giant parotid PA is reported as large as 35 cm (diameter) and 7.3 kg (resected weight). Although rare, 10 cases of malignant transformation were reported in the review. Surgical management included extracapsular dissection (ECD), superficial parotidectomy, and total parotidectomy for benign tumors, and adjuvant radiation or chemotherapy for malignant tumors. We further present the case of a 36-year-old healthy male with slow-growing and asymptomatic giant parotid PA, of 4-year duration. The patient presented with firm, lobulated preauricular swelling, provisionally diagnosed as PA based on radiographic and cytological findings. The tumor was resected through ECD, and the patient had uneventful postoperative recovery and a 7-year recurrence-free follow-up period. Histological examination revealed epimyoepithelial proliferation punctuated by chondromyxoid areas, with extensive squamous metaplasia and keratin cysts. To the best of knowledge from indexed literature, giant parotid PA is rarely reported in Saudi Arabia. In addition to its rarity, this case is reported for its benign nature despite atypical histological presentation, successful surgical management without complications, and long-term recurrence-free follow-up. Based on this report, clinicians must be aware of atypical histological presentations associated with PA and plan suitable surgical management and follow-up to avoid morbidity. Nevertheless, attempts must be made to diagnose and manage these lesions at an early stage and before they reach gigantic proportions.

Xanthogranulomatous change in a pleomorphic adenoma: An extremely rare variant/degenerative change. Is it fine needle aspiration induced?

Pleomorphic adenoma (PA) is the most common benign salivary gland tumor characterized by morphological diversity, metaplastic changes, degeneration, cystic change, altered differentiation, and rarely malignant transformation, thereby may create a diagnostic dilemma on cytology. Xanthogranulomatous (XG) inflammation within a PA could be due to XG sialadenitis coexistent with PA or preoperative fine-needle aspiration cytology (FNAC) induced histologic alteration. The argument in favor of this hypothesis is that the changes seen in the histopathology would not be present in the cytology, implying that the alterations were most likely due to the traumatic injury of needling rather than spontaneous change of the lesions themselves. These FNAC induced changes are focal in most of the cases, so the underlying lesion is readily identifiable, but on rare occasions they are so extensive that it can masquerade as a malignancy. We report a case of XG change in a PA in a 39-year-old male of 8 years standing. Through this case we wish to emphasize that knowledge of a previous FNAC and its potential effects on histology of the subsequent surgical specimen is necessary to avoid potential misdiagnosis.

A Study of Clinicopathological Profile of Salivary Gland Swellings

Salivary gland diseases usually present as a swelling of the affected gland. These lesions are commonly encountered in day to day practice. A salivary gland swelling can present in a variety of locations, depending on the salivary gland affected. The purpose of the study is to know the incidence of salivary gland swellings and the usefulness of FNAC in evaluating these swellings. The present study is a time bound prospective study of fifty consecutive cases of salivary gland swellings admitted in our hospital during the period November 2014-August 2016. Most of the patients underwent pre-operative work up with FNAC and patients indicated for surgery underwent surgery and HPE. Salivary gland swelling occurred more commonly in 3rd decade of life and equal number of cases were seen in both genders. Most of the patients presented with salivary gland swelling (98%). 21 (42%) were non neoplastic, 29 (58%) were neoplastic swellings, 18 (36%) were benign of which pleomorphic adenoma was the most common and 11 (22%) were malignant of which adenoid cystic carcinoma was the most common. Parotid gland was the most common gland involved. Fine needle aspiration cytology was highly sensitive for benign tumours and highly specific for malignant tumours. FNAC should be first choice of investigation in evaluating the salivary gland pathologies. Early diagnosis and subsequent appropriate management carries good prognosis.

The Value of Ultrasound-Guided Fine-Needle Aspiration Cytology by Cytopathologists in the Diagnosis of Major Salivary Gland Tumors

Because of the typical sonographic appearances of many salivary gland masses, as well as the normal appearance and anatomy of the glands, differentiation of salivary glands tumors based only on clinical and imaging criteria is difficult. We compared the utility, safety, specificity, and accuracy of ultrasound-guided fine needle aspiration cytology (UG-FNAC) in the detection of nonpalpable tumors in the major salivary glands. A retrospective review was done of a 5-year experience of 102 consecutive patients undergoing UG-FNAC. Clinical opinion, FNA results, and final pathologic findings were examined. Histological evaluation showed 29 malignant tumors and 54 benign lesions (neoplasms and nonneoplastic lesions). The cytologic findings were nondiagnostic in 19 cases (18.6%), true negative in 50 (49%), true positive in 20 (19.6%), false negative in 9 (8.8%), and false-positive in 4 (3.9%) cases for detecting malignant tumors. Six of 20 (30%) malignant tumors (true positive) and 41 of 50 (82%) benign lesions (true negative) were classified accurately. The accuracy, sensitivity, and specificity were 84.3%, 68.9%, and 92.6%, respectively. Ultrasound guided FNAC was found to be highly specific for malignancy and its sensitivity for malignancy was good. It is a reliable and accurate diagnostic technique with minimal complications and easy to perform with high specificity 92.5% (95% CI: 82.09%-97.90%). It should be the preferred primary approach for initial investigation in diagnosing salivary gland tumors.

Cystic Change in Pleomorphic Adenoma: A Rare Finding and a Diagnostic Dilemma

Pleomorphic adenoma forms the majority of salivary gland neoplasms. Cystic change in pleomorphic adenomas is a diagnostic dilemma and can mimic mucoepidermoid carcinoma, mucocele or carcinoma ex pleomorphic adenoma and squamous cell carcinoma. Hereby we report this interesting and rare case of cystic pleomorphic adenoma in a 32-year-old male.

High diagnostic accuracy and reproducibility of fine-needle aspiration cytology for diagnosing salivary gland tumors: cytohistologic correlation in 182 cases

OBJECTIVE

The purpose of this study was to assess the efficacy and reproducibility of the cytologic diagnosis of salivary gland tumors (SGTs) using fine-needle aspiration cytology (FNAC). The study aimed to determine diagnostic accuracy, sensitivity, and specificity and to evaluate the extent of interobserver agreement.

STUDY DESIGN

We retrospectively evaluated SGTs from the files of the Division of Pathology at the Clinics Hospital of São Paulo and Piracicaba Dental School between 2000 and 2006.

RESULTS

We performed cytohistologic correlation in 182 SGTs. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 94%, 100%, 100%, 100%, and 99%, respectively. The interobserver cytologic reproducibility showed significant statistical concordance (P < .0001).

CONCLUSIONS

FNAC is an effective tool for performing a reliable preoperative diagnosis in SGTs and shows high diagnostic accuracy and consistent interobserver reproducibility. Further FNAC studies analyzing large samples of malignant SGTs and reactive salivary lesions are needed to confirm their accuracy.

Pleomorphic adenoma palate: Major tumor in a minor gland

Pleomorphic adenoma (PA) is the most common benign mixed salivary gland neoplasm that accounts for 60% of all benign salivary gland tumors. It has diverse histological presentation and occurs in both major and minor salivary glands. PA of minor salivary gland in the palate is a common entity. We report the case of a 45-year-old female who presented with a painless slow growing swelling of palate over the last 20 years. The mass was extending to oropharynx causing mechanical obstruction of airway. Magnetic resonance imaging (MRI) depicted an oval-shaped mass occupying oropharynx and displacing the tongue inferiorly. Fine needle aspiration cytology (FNAC) was suggestive of PA. The entire tumor mass was excised along with overlying mucosa. Histopathological examination confirmed diagnosis of PA of minor salivary gland. There has been no recurrence of the lesion since 1 year.

Correlation between cytology and histopathology of the salivary glam

BACKGROUND

Salivary gland swellings can result from tumours, an inflammatory process, or cysts. It can sometimes be difficult to establish whether pathology arises from the salivary gland itself or adjacent structures. Fine needle aspiration cytology (FNAC) is a simple, rapid and safe method to diagnose salivary gland swelling. FNAC has high sensitivity, specificity and accuracy. The aims of this study are to correlate FNAC diagnoses with histopathology and to establish the sensitivity and specificity of FNAC in diagnosis of salivary gland swellings in our institution.

METHOD

The study was conducted in the department of pathology, Sri Venkateshwara Medical college Hospital and research Centre, Pondicherry, India. Data was collected retrospectively for the time period 2007-2008 and prospectively for that obtained between January 2009 and June 2010. Results of cytologicial assessment were compared with histopathological data where possible to establish sensitivity and specificity of FNAC.

RESULTS

During the study period, 1309 FNAC were undertaken of which 96 FNAC were of salivary gland swellings. Correlation of cytology from FNAC with histopathology tissue was possible in 56 cases. Of the 96 cases for which FNAC data was available, 38.56% were from male and 61.45% were from female patients. The age of the patients ranged from 8 to 69 years. 48.95% cases were benign swellings, 13.54% were malignant, 6.25% were cysts and 31.25% had an inflammatory aetiology. Comparison of FNAC findings with histopathology specimens was available for 56 (58.33%) cases, following which the sensitivity and specificity of cytology were found to be 76.9% and 97.1% respectively.

CONCLUSION

FNAC is highly sensitive and specific technique for diagnosis of most of the salivary gland swelling. FNAC can be used preoperatively to avoid unnecessary surgery and discomfort associated with open biopsy.

The cell with a thousand faces: detection of myoepithelial cells and their contributions in the cytological diagnosis of salivary gland tumors

Myoepithelial cells are an important component of salivary gland tumors and are partly responsible from the diverse histology of them. In this study, we focus on the myoepithelial cell differentiation by using cytological morphology in a various types of salivary gland tumors especially with regard to their contribution to the diagnosis. The relation of myoepithelial cells with stromal matrix and the associated epithelial cells were evaluated. Cytologic slides of one hundred and forty one benign and twenty malignant salivary gland tumors were examined for identification of morphologically different myoepithelial cells such as; spindle-stellate, polygonal-epitheloid, plasmacytoid, basal and clear types. The best examples of myoepithelial cells were detected in pleomorphic adenomas, in some monomorphic adenomas and in the adenoid cystic carcinoma cases. Most of the pleomorphic adenomas were composed more than one type of myoepithelial cells and epitheloid-spindle cell combination was frequent. Basal and clear cell types of myoepithelial cells closely resembled the epithelial cells and their identification was relatively difficult. Identification of myoepithelial cell types was easier when they were associated with stromal matrix material and stood as a secondary layer around tubule-forming epithelial cells. Myoepithelial cell components of various salivary gland tumors may be quite different and identification of myoepithelial cell types may pose difficulties. A confident cytologic identification of myoepithelial cells may be critical part of diagnosing salivary gland tumors.

Pleomorphic adenoma with squamous and appendageal metaplasia mimicking mucoepidermoid carcinoma on cytology

Background:

Histological diversity is the hallmark of pleomorphic adenoma, the most common salivary gland tumor. It may cause difficulty in cytological interpretation, due to limited and selective sampling.

Case presentation:

A 16-year-old female patient presented with right cheek swelling. Fine needle aspiration cytology showed squamous cells, basaloid cells, and foamy cells, along with extracellular keratin and foreign body giant cells. Characteristic metachromatic fibrillary chondromyxoid stroma, which is usually seen in pleomorphic adenoma, was not seen in the aspirate. A diagnosis of mucoepidermoid carcinoma was given on cytology. Subsequent resection revealed an encapsulated pleomorphic adenoma, with extensive squamous metaplasia and appendageal differentiation on histology.

Conclusion:

This case illustrates that pleomorphic adenoma with squamous metaplasia presents a potential for misinterpretation as mucoepidermoid carcinoma on cytology. We discuss the various pitfalls and the features that are helpful in distinguishing these two lesions.

[Epidemiology, diagnosis, and treatment of giant pleomorphic adenomas of the parotid gland]

Pleomorphic adenomas of the parotid gland can be slowly growing over the course of many years and may reach an enormous and disfiguring size associated with significant morbidity of the patients. To our knowledge, over the last 80 years 20 cases of giant pleomorphic adenomas (weight 1.2-26.5 kg) have been reported. These tumors occurred predominantly in women (90%). The mean period from initial clinical manifestation until definitive surgical treatment was 20.7 years. The mean age of the patients at the time of surgery was 58.9 years. Malignant transformation occurred in 15.8% of cases. It is likely that the reasons for delayed treatment are the patient's fear of surgery on the one hand, and insufficient medical advise on the other. We report on a 77 year old female who had a 40-year history of a growing parotid tumor that weighed 3.9 kg after resection. The implications of this case for diagnosis and treatment of giant pleomorphic adenomas, and a review of the world literature on these unusual parotid tumors, are presented.