Retrospective study of 124 cases of salivary gland tumors and literature review

Effective Management of a Giant Deforming Pleomorphic Adenoma With Airway Displacement in a 93-Year-Old Patient: A Case Report

Benign salivary gland tumors are a rare and diverse group of neoplasms with significant variations in their site of origin, histological features, and biological behavior. This report describes the case of a 93-year-old woman with a markedly enlarged left cervical mass. Physical inspection uncovered a tumor of approximately 32 x 30 cm, featuring necrotic and ulcerated areas. The neoplasm, diagnosed as a pleomorphic adenoma (PA) through prior biopsies, had been growing gradually over fifteen years, with delayed surgical intervention due to concerns about her age and the tumor's size. Preoperative contrast-enhanced CT imaging showed a large left-sided cervical mass in close proximity to the airway, but without displacement or infiltration into major structures. An elective surgical approach was undertaken, involving complete resection of the giant PA, confirmed by histopathological evaluation. During the first month of postoperative follow-up, the patient experienced partial facial nerve paralysis but showed no evidence of tumor recurrence. Despite the tumor's considerable size, proximity to the airway, and the patient's advanced age, curative surgical intervention proved feasible. This case underscores that, with meticulous preoperative planning and careful surgical execution, age should not be a contraindication for surgery.

Unprecedented association: Enormous calculus concomitant with salivary gland tumor

Calculus represents a mineralized form of bacterial plaque, commonly developing on natural tooth surfaces exposed to a continuous supply of saliva. The salivary composition significantly influences the degree of calculus formation in individuals, exerting a pivotal role in this aspect. Reduced salivary output elevates vulnerability to oral diseases. Numerous contributing elements might be associated with the development of significant calculus, potentially implicating the existence of a salivary gland tumor, notably related to the left parotid gland. This report stands as notable documentation of an extraordinary and infrequent occurrence of calculus formation associated with a salivary gland tumor, presenting an exceptional case within the scope of medical literature.

Oncologic outcomes of the most prevalent major salivary gland cancers: retrospective cohort study from single center

BACKGROUND

The preoperative diagnosis of salivary gland cancer (SGC) is crucial for the application of appropriate treatment, particularly involving the extension of the resection.

METHODS

Retrospective search of medical database identified 116 patients treated surgically with malignant tumors of salivary gland between 2010 and 2020. Analysis included the demographical data, clinical course, type of surgical and adjuvant treatment, histology type and margin status, perivascular invasion (LVI), perineural invasion (PNI), metastatic lymph nodes (LN). Facial nerve function, recurrence-free and overall survival were evaluated. Adequate statistics were used for data analysis.

RESULTS

The final cohort included 63 SGC patients, with adenoid cystic carcinoma the most common pathological type (27%, n = 17), followed by adenocarcinoma (17.4% n = 11). T1 and T2 patients accounted for majority cases (n = 46). The lymph node metastases were confirmed with the histopathology in 31.7% (n = 20). Distant metastases were observed in 4.8% of cases (n = 3). 38% (n = 24) of SGC were treated selectively with surgery, 49.2% (n = 31) had postoperative radiotherapy and 15.9% (n = 10)-radio-chemotherapy. The final facial nerve function was impaired in 38% of patients. Mean overall survival (OS) for all patients was 108.7 (± 132.1) months, and was the most favorable for acinar cell carcinoma (118.9 ± 45.4) and the poorest for squamous cell carcinoma (44 ± 32). Cox regression analysis of disease-free survival and OS identified significant association only with patients' age over 65 years, the hazard ratio of 7.955 and 6.486, respectively.

CONCLUSIONS

The efficacy of treatment modalities for SGC should be verified with regard to the histopathological type, but also the patients' age should be taken into account.

Influence of p16 Protein Immunostaining on Histopathological Features of Pleomorphic Adenoma and Carcinoma ex- Pleomorphic Adenoma

The objective of this study was to evaluate the role of p16 in histologic characteristics and transition of Pleomorphic Adenoma (PA) to Carcinoma ex-PA (CxPA). So, 60 PA and 4 CxPA were histologic reviewed based on microscopic characteristics proposed by Hellquist, Triantafyllou and Dulguerov (PA) and Morais, Antony and Toluie (CxPA). Immunostaining for p16 was associated in different parenchyma and stroma of both tumors and Fisher's/chi-square tests and Mann-Whitney test were performed (SPSS v20.0, p<0.05). In PA the periductal cells were predominantly p16- and that ductal and myoepithelial cells showed a significant increase in p16+ cells (p<0.001). In CxPA, none of the cases showed p16+ in periductal cells, most parotid cases showed p16+ in ductal cells, and one case of parotid and the submandibular case showed mild immunostaining for myoepithelial cells. There was a small reduction in p16+ in CxPA compared to PA (p=0.537), but in both tumors there was less p16+ cells in solid stroma than other (p<0.001). The p16+ cases of PA had a higher capsular thickness (p=0.047). So, the loss of p16 immunostaining does not seem to be associated with the transition from PA to CxPA, but in both tumors the loss of p16+ cells are related to microscopic aggressiveness.

Salivary Gland Tumors in Iran: A Systematic Review of 2870 Cases Based on the New WHO Classification

Background & Objective

There is no consensus on the prevalence of salivary gland tumors (SGTs) in Iran. Thus, we systematically reviewed the literature about the prevalence of SGTs in Iran and applied the last world health organization (WHO) classification.

Methods

The systematic literature search was performed in EMBASE, Scopus, PubMed MEDLINE, Google Scholar, Scientific Information Database (SID), and Magiran; we searched for "salivary gland," "tumor," "prevalence," and "Iran" until 1 March 2021. The studies included were written in the English and Farsi languages. The weighted mean prevalence of SGTs was calculated as prevalence (%) * (N/the sum of all N). We used the unpaired Two-sample T-test to compare the weighted means.

Results

A total of 17 studies, including 2870 patients, were selected for the data synthesis. The weighted mean prevalence of benign and malignant tumors was 66% (95% CI: 59-73) and 34% (95% CI: 27-41), respectively. The patients' mean age was reported in 10 out of the 17 studies. The weighted mean age of the patients was 40 (95% CI: 37-42) and 49 (95% CI: 43-55) years for benign and malignant tumors, respectively (P=0.01). Pleomorphic adenoma (PA), followed by Warthin's tumor (WT), was the most prevalent benign tumor. Moreover, the most common malignant tumors were mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (AdCC).

Conclusion

More than one-third of SGTs in Iran were malignant, which is higher than the reports from Middle Eastern countries. Information about risk factors and the burden of SGTs in Iran is insufficient. Thus, further well-designed longitudinal studies are warranted.

Clinical parameters predictors of malignant transformation of recurrent parotid pleomorphic adenoma

Malignant transformation (MT) in recurrent parotid pleomorphic adenomas (PAs) is rare; therefore its occurrence lacks reliable predictive factors. Our goal was to clarify the predictors for MT of recurrent parotid PAs based on preoperative clinical parameters. Patients with a clinical diagnosis of recurrent parotid PA were retrospectively enrolled. The association between clinicopathologic variables and MT of PA was assessed using univariate and multivariate analyses. MT occurred in 11.8% of the 467 patients. In univariate analysis, three or more previous recurrences, newly developed facial nerve paralysis, difficulty in mouth opening, tumors with the largest tumor diameter ≥ 2.4 cm, and abnormal neck lymph node enlargement were associated with MT occurrence. Further, multivariate analysis showed that three or more previous recurrences, newly developed facial nerve paralysis, difficulty in mouth opening, and abnormal neck lymph node enlargement were independently related to MT. MT of recurrent PA was not uncommon. Clinical signs of malignancy included newly developed facial nerve paralysis, difficulty in mouth opening, three or more previous recurrences, and abnormal neck lymph node enlargement.

Results of 301 Parotidectomies: A Twenty-Year Experience of One Single Institution

To evaluate demographic, clinical, surgical and histopathological results and complications of 301 parotidectomies performed in southern part of Turkey. The results of 297 patients undergoing 301 parotidectomies between 2000 and 2019 were retrospectively reviewed. Four patients underwent bilateral parotidectomy. Age, gender, side and size of lesion, postoperative facial nerve function (FNF) for benign tumors and types of surgery were evaluated. There were 172 male and 125 female patients. The mean age was 52.53 ± 16.67 years (range 11-90 years). Patients with malignant tumor had higher mean age than the patients with benign diseases (p < 0.001) and the mean age of Warthin tumor (WT) patients was significantly higher than pleomorphic adenoma (PA) (p < 0.001). There was a significant male dominancy in WTs than the PAs (p < 0.001). The mean size of the malignant tumors was significantly higher than the benign tumors (p = 0.012). The mean of cigarette smoking value (pack/year) was higher in WTs than the PAs (p < 0.001). WT incidence was slightly higher than PA in between years 2010 and 2019 (p = 0.272) compared to between years 2000 and 2009. Fine needle aspiration biopsy had a sensitivity of 96% and specificity of 78% for the benign tumors. Tumor location (p < 0.001) and tumor size (p = 0.034) had negative effect on the postoperative FNF. The incidence of WT had a significant rise in the last decade. Deep lobe tumors and increased tumor size had effect postoperative FNF. Experience of surgeon is more important than nerve monitoring to prevent facial paralysis. Partial superficial parotidectomy was available methods for small benign tumors in tail of the parotid gland.

Salivary gland tumors: A 13-year clinicopathologic retrospective study in a Brazilian northeast population

Background

The present study aimed to evaluate the clinicopathologic features of salivary gland tumors (SGTs) in a Brazillian northeast population.

Material and Methods

A retrospective descriptive cross-sectional study was performed (1995-2009). All cases of SGTs diagnosed in a private surgical pathology service in Brazil were reviewed, and clinicopathological data were collected.

Results

A total of 23.258 histopathological records of biopsies were analyzed, and 174 cases were diagnosed as SGTs (0.7%). Of these, 117 (67.2%) were classified as benign, and 57 (32.8%) were malignant. The series comprised 89 females (51.1%) and 85 males (48.9%), with a mean age of 50.2 years (range: 3-96 years) and a roughly equal female-to-male ratio (1:1). Most tumors occurred in the parotid gland (n = 82, 47.1%), followed by the palate (n = 45, 25.9%), submandibular gland (n = 15, 8.6%). Pleomorphic adenoma (n = 83; 70.9%) and mucoepidermoid carcinoma (n = 19, 33.3%) were the most frequent benign and malignant tumors, respectively. After reevaluation of morphology and immunohistochemical analysis, seven tumors (4.0%) were reclassified following the current WHO Classification of the Head and Neck Tumors.

Conclusions

The general features of SGT from the studied Brazilian population were similar to previously published reports in other countries. However, SGTs do not show any sex predilection. Although careful morphological analysis is the key to the correct diagnosis of these tumors, immunohistochemical analysis is essential to establish an accurate diagnosis in the face of challenging cases. Key words:Salivary gland tumors, epidemiology, head and neck pathology.

INFLUENCE OF THE PATIENT'S SEX AND AGE, VOLUMES OF THE SALIVARY GLAND AND PLEOMORPHIC ADENOMA ON THE TUMOR HISTOLOGICAL VARIANTS

OBJECTIVE

Aim: The purpose of the study was to identify the influence of the patient's sex and age, the volumes of the salivary gland and pleomorphic adenoma on the histological variants of the tumor.

PATIENTS AND METHODS

Materials and Methods: The study included 21 women and 9 men with pleomorphic adenomas of the salivary gland. In 15 cases, a mesenchymal variant of pleomorphic adenoma was identified, in 5 cases - an epithelial variant, in 10 cases - a mixed variant. The average age of the patients was 39.7±2.9 years. Patients with pleomorphic adenomas underwent magnetic resonance imaging using a Siemens MAGNETOM Aera 1.5T device (Germany), during which three projections of the tumor and salivary gland were measured (antero-posterior, lateral, vertical) with subsequent calculation of their volumes, and then the ratios of these volumes. Classification trees were used to determine whether patients belonged to one of three variants of pleomorphic adenoma. The CART (Classification And Regression Tree) algorithm was used as a branching option. Stopping branching was carried out using the FACT (Fact-style direct stopping) method until each terminal (final) node of the tree does not contain incorrectly classified observations or when their number becomes less than a given proportion of the total group size (less than 5%). Determination of the structure and relationships between the tumor variants and such indicators as gender, age and radiological indicators (volume of the tumor, volume of the salivary gland, ratio of tumor volume to salivary gland volume) was carried out using correspondence analysis.

RESULTS

Results: Epithelial variant of pleomorphic adenoma is more typical for women, and the mixed and mesenchymal variant is more common for patients of both sexes. The epithelial variant can develop in patients of any age, while the mixed variant occurs mainly in patients older than 41 years, and the mesenchymal variant - mainly in patients younger than 41 years. The ratio of the volume of the tumor to the volume of the salivary gland will be predominantly >0.17 in the epithelial variant of pleomorphic adenoma, predominantly ≤0.17 in the mesenchymal variant, and can take any value in the mixed variant.

CONCLUSION

Conclusions: The authors conducted a study in order to identify the influence of sex, age of the patient, and the ratio of the volume of pleomorphic adenoma to the volume of the salivary gland on the histological variant of the tumor. The revealed data will be useful in the treatment and diagnostic process in patients with pleomorphic adenoma of the salivary gland.

[Salivary gland carcinomas - Monocentric experience on subtypes and their incidences over 42 years]

OBJECTIVE

Salivary gland carcinomas are rare and heterogeneous. More than 20 subtypes are recognized and risk factors are diverse. The aim of this work was to evaluate the subtype and other risk factors in a monocentric population from more than four decades.

MATERIAL AND METHODS

205 cases (diagnosis period 1972-2014) were retrospectively collected and analyzed with regard to the distribution of risk factors and their influence on overall survival (OS).

RESULTS

19/24 (79.2%) of the subtypes listed in the WHO classification occurred rarely in the cohort (< 5%). 10/24 (41.7%) of all subtypes were never diagnosed. With a total of 145/205 cases (70.7%), squamous cell carcinoma (PEC), adenocarcinoma (AdenoCa), acinar cell carcinoma (AcinarCa), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC) were by far the most common subtypes. Risk factors are significantly different in these groups (e.g., lymphogenic metastasis and degree of differentiation in AdenoCa and age, T and UICC stage in PEC). The 5-year overall survival of all patients was 66.9% and differed significantly within the most common subtypes. An independent impact on overall survival was detectable for patient age (p<0.001), and T- (p=0.003) and N-stage (p=0.046) in multivariate analysis.

CONCLUSIONS

Most subtypes occurred markedly rarely or not at all within decades. The most common diagnoses differ with respect to risk factors as well as OS and 3 risk groups can be defined based on histology. In conclusion, considering TNM alone is insufficient for prognosis estimation in salivary gland carcinoma.

AN INTEGRATED APPROACH TO THE MORPHOLOGICAL DIAGNOSIS OF DIFFERENT TYPES OF PLEOMORPHIC ADENOMAS OF THE SALIVARY GLAND: LONG-TERM RESEARCH RESULTS

OBJECTIVE

The aim: To describe an integrated approach to the morphological diagnosis of different types of pleomorphic adenomas of the salivary gland.

PATIENTS AND METHODS

Materials and methods: Surgical and biopsy material from 30 patients with pleomorphic adenomas of epithelial, mixed and mesenchymal variants was studied using histological, immunohistochemical, genetic, morphometric and statistical methods.

RESULTS

Results: The results of research allowed us to identify methods for determination the pleomorphic adenomas types. The first method requires an immunohistochemical reaction with a monoclonal antibody to human papillomavirus type 16, followed by counting the percentage of positively stained cells in the tumor. Thus, the mesenchymal variant of the tumor is diagnosed when the percentage of positively stained cells is < 40%. In the mixed variant, this indicator is ≥ 40%, but ≤ 70%, and in epithelial variant - > 70%. The second method was based on the multivariate discriminant analysis. Three formulae were derived to determine the tumor types (Fmesenchymal = - 41.03 + 4.96Х1 + 1.11Х2, Fepithelial = - 22.27 + 3.46Х1 + 0.85Х2, Fmixed = - 122.25 + 5.63Х1 + 3.2Х2, here Х1 - number of vessels, Х2 - specific volume of parenchyma).

CONCLUSION

Conclusions: The authors identified several methods for determining the histological variants of pleomorphic adenomas. These methods will improve the morphological diagnosis of pleomorphic adenomas variants in the preoperative and postoperative periods.

Salivary Gland Disorders in Pediatric Patients: A 20 Years’ Experience

Salivary gland disorders are uncommon in children; they show a lower prevalence when compared to adults. The literature has a relative lack of information about the management and the different treatment protocols regarding these diseases. The aim of this research is to investigate the prevalence of both benign and malignant salivary gland disorders, focusing on diagnostic and therapy. An audit of patients diagnosed with salivary gland disorders was conducted from 2000 to 2020. 99 patients’ records were selected and analyzed: 51 males’ and 48 females’, age 10 ± 4 SD. Obstructive pathologies were the most frequently diagnosed (49 patients) followed by oncologic (21 patients), inflammatory (20 patients), rheumatologic (4 patients), malformative (3 patients) and infective disorders (2 patients). The parotid was the most affected major gland in 47 cases with a prevalence of diagnosis of juvenile recurrent parotitis (JRP) (40.4%), followed by the sublingual gland in 14 cases of ranula (100%) and the submandibular gland in 11 patients suffering from sialolithiasis (84.6%). Swelling was the most common symptom (75.7% of patients). Seven different neoplasms were documented. A greater prevalence of low-grade mucoepidermoid carcinoma among the malignant group (38.1% of oncologic cases) was noted. In regards to benign tumors, pleomorphic adenoma was the most common diagnosis (47.6% of cases). The symptoms and outcomes showed statistical significance concerning gender. Although salivary gland diseases in children and adolescents are rare, it is essential to observe and monitor all of the symptoms to intervene if necessary, as painless swelling is a symptom common from both benign and malignant diseases.

[Neglected parotid tumors: case report]

Tumors of the parotid gland can be challenging if left untreated. We report three cases of patients with initial clinical and therapeutic manifestations of neglected parotid tumours in Madagascar: two women and one man aged 42, 47 and 51 years, with tumours that had been developing for 4, 7 and 11 years respectively. One patient was suspected to have malignant tumour due to skin necrosis. The diagnosis was then confirmed by cytopuncture. After obtaining the informed consent, total parotidectomy was performed in all patients. Facial nerve sacrifice with cervical lymph node dissection was established in the patient with a malignant tumour. No intraoperative adverse events were reported. Parotid tumors can become cancerous without proper treatment. Socio-economic factors are involved in delayed consultation. However, early consultation in patients with parotid tumors would prevent management risks.

Application value of shear wave elastography in salivary gland tumors

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

[Epithelial salivary gland tumors - a monocentric retrospective study of South Saxony-Anhalt]

OBJECTIVE

 The purpose of this research was to analyze all epithelial salivary gland tumors in this region in a comprehensive monocentric, retrospective study.

MATERIAL AND METHODS

 In the period from 1993 to 2017, all patients with the diagnosis of epithelial salivary gland tumors either treated at the Department of Oral and Maxillofacial Plastic Surgery of the Martin Luther University, Halle-Wittenberg (MLU), University hospital and/or processed at the Institute of Pathology of the MLU, University hospital and/or registered between 2000 and 2017 by the "Statistisches Landesamt" Sachsen-Anhalt were analyzed. The following parameters were summarized and statistically analyzed in a database using SPSS 21.5: demographic data, tumor localization, entity, therapy and disease course.

RESULTS

 382 patients with the diagnosis of epithelial salivary gland neoplasia were identified. With 71 % the most frequent tumor localization was the glandula parotis [n = 271]. 15 % of the tumors originated from minor salivary glands [n = 57]. Most tumors were benign at over 80 % [n = 307]. In Saxony-Anhalt, 5586 patients with epithelial salivary gland tumors were reported in the mentioned period.

CONCLUSION

 To the best of our knowledge this is the first epidemiologic analysis of frequency, valency and therapy of salivary gland tumors in Saxony-Anhalt. The results confirm the predominance of benign epithelial salivary gland tumors, most of all pleomorphic adenoma in the glandula parotis. Concerning the group of malignant epithelial salivary gland tumors adenoid cystic carcinoma located in the minor salivary glands were most common.

Incidence and profile of benign epithelial tumors of salivary glands from a single center in Northeast of Brazil

Background

Benign tumors of the salivary glands are a group of lesions with varied histopathological and clinical spectrum. The aim was to determine the incidence and clinicopathological characteristics of benign salivary gland neoplasms diagnosed between 2007 and 2016 in a single center located in northeastern Brazil.

Material and Methods

Records regarding sex, age, anatomical location, histopathological subtype and treatment were retrieved, and data were analyzed using the Stata/IC software (version 12.0).

Results

There were above 7,100 cases of neoplasms in the head and neck region, of which 403 corresponded to salivary gland neoplasms. Of these, 238 (59%) were benign, being pleomorphic adenoma (PA) the most frequent neoplasm (n=178; 74.8%), followed by Warthin's tumor (WT) (n=23; 9.7%). Overall, most cases occurred in females (n=136; 57.1%) and age ranged from 11 to 83 years. The parotid gland (n=188; 79%) was the most common anatomical site, and all patients were treated by surgical excision. Of the cases diagnosed as PA, malignant transformation to carcinoma ex-pleomorphic adenoma (CAEXPA) occurred in 7 (3.9%) cases.

Conclusions

The present study confirmed the clinical and demographic profile of benign salivary gland neoplasms, which contributes to the continuous knowledge of current data about these lesions.

Key words:Salivary gland, benign neoplasms, epidemiology.

Salivary Gland Carcinoma: Novel Targets to Overcome Treatment Resistance in Advanced Disease

Salivary gland carcinomas (SGCs) account for <5% of head and neck malignant neoplasms, further subcategorized in over 20 histological subtypes. For the most part, treatment for advanced disease is guided by morphology. SGCs in general respond poorly to a wide array of standard chemotherapy, with short durability, and significant toxicity. More recently, next-generation sequencing provided significant input on the molecular characterization of each SGC subtype, not only improving diagnostic differentiation between morphologically similar tumor types but also identifying novel driver pathways that determine tumor biology and may be amenable to targeted therapy. Among the most common histological subtype is adenoid cystic carcinoma, which often harbors a chromosome translocation resulting in an MYB-NFIB oncogene, with various degrees of Myb surface expression. In a smaller subset, NOTCH1 mutations occur, conferring a more aggressive pattern and potential sensitivity to Notch inhibitors. Salivary duct carcinomas may overexpress Her-2 and androgen receptors, with promising clinical outcomes after exposure to targeted therapies approved for other indications. Secretory carcinoma, previously known as mammary analog secretory carcinoma, is distinguished by an ETV6-NTRK3 fusion that can both help differentiate it from its morphologically similar acinar cell carcinoma and make it susceptible to Trk inhibitors. In the present article, we discuss the molecular abnormalities, their impact on tumor biology, and therapeutic opportunities for the most common SGC subtypes and review published and ongoing clinical trials and future perspectives for this rare disease.

Salivary Gland Tumors: A Retrospective Study of 164 Cases from a Single Private Practice Service in Mexico and Literature Review

Salivary gland tumors (SGT) represent an uncommon heterogeneous group of tumors with complex clinical and pathological characteristics. The prevalence of these lesions varies between studies but has been estimated between 3 and 6% of all tumors in the head and neck region. The present study aimed to evaluate the distribution and demographic findings of salivary gland tumors diagnosed in an oral pathology service in Mexico. A retrospective descriptive cross-sectional study was performed. A total of 164 cases of SGT from a private oral pathology service were diagnosed between 2000 and 2019 in Mexico City. All cases were reviewed histologically, and demographic data and histopathological diagnoses were collected. A total of 110 (67.1%) tumors were benign, and 54 (32.9%) were malignant. The majority of patients were female (n = 100, 61.0%) with an overall female:male ratio of 1.6:1. The minor salivary glands were affected more than the major salivary glands (68.9% vs. 25.6%). The palate (n = 67, 40.9%) was the most commonly affected site, followed by the parotid gland (n = 37, 22.6%), lips (n = 16, 9.8%), and buccal mucosa (n = 14, 8.5%). Pleomorphic adenoma (n = 88; 80.0%) and mucoepidermoid carcinoma (n = 16, 29.6%) were the most frequent benign and malignant tumors, respectively. The general features of SGT from the studied Mexican population shared some similarities and differences compared to previously reported series from various parts of the world.

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.