Salivary gland tumors in Turkey: demographic features and histopathological distribution of 510 patients

Current Developments in Diagnosis of Salivary Gland Tumors: From Structure to Artificial Intelligence

Salivary glands tumors are uncommon neoplasms with variable incidence, heterogenous histologies and unpredictable biological behaviour. Most tumors are located in the parotid gland. Benign salivary tumors represent 54-79% of cases and pleomorphic adenoma is frequently diagnosed in this group. Salivary glands malignant tumors that are more commonly diagnosed are adenoid cystic carcinomas and mucoepidermoid carcinomas. Because of their diversity and overlapping features, these tumors require complex methods of evaluation. Diagnostic procedures include imaging techniques combined with clinical examination, fine needle aspiration and histopathological investigation of the excised specimens. This narrative review describes the advances in the diagnosis methods of these unusual tumors-from histomorphology to artificial intelligence algorithms.

Clinical and demographic features of minor salivary gland tumors: A collaborative study of 480 cases

OBJECTIVE

To describe the frequency, clinical, and demographic features of minor salivary gland tumors and possible associated factors.

MATERIALS AND METHODS

A cross-sectional study was conducted. Clinical and demographic data were collected from biopsy records of two oral pathology services. Chi-square test, Fisher's exact test, and descriptive statistical analysis were performed.

RESULTS

A total of 480 (0.89%) minor salivary gland tumors were retrieved, 272 (56.7%) benign and 147 (30.7%) malignant. Sixty-one (12.6%) had no subtype specification. Most patients were women (307/64.0%), in sixth decade of life (80/16.7%), with a mean age of 45.32 years. Palate was the most common site (336/70.1%). Pleomorphic adenoma (PA; 245/51.1%), mucoepidermoid carcinoma (MEC; 70/14.6%), and adenoid cystic carcinoma (ACC; 43/8.9%) were the most frequent tumors. Symptomatic case, recurrence, and tobacco use were associated with malignancy (p < 0.05). PA and MEC were more frequent in palate (p < 0.05). No association between the three most frequent histological types and gender or age group was observed (p > 0.05).

CONCLUSIONS

This represents one of the largest exclusive series of minor salivary gland tumors in Brazil and worldwide. PA, MEC, and ACC were the most frequent tumors. Clinical and demographic data are similar from Brazilian studies or from other countries.

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.

Epithelial salivary gland tumors in pediatric patients: An international collaborative study

OBJECTIVE

Salivary gland tumors (SGT) are a diverse group of uncommon neoplasms that are rare in pediatric patients. This study aimed to characterize the clinicopathological profile of pediatric patients affected by SGT from a large case series derived from an international group of academic centers.

STUDY DESIGN

A retrospective analysis of pediatric patients with SGT (0-19 years old) diagnosed between 2000 and 2021 from Brazil, South Africa, and the United Kingdom was performed. SPSS Statistics for Windows was used for a quantitative analysis of the data, with a descriptive analysis of the clinicopathological characteristics and the association between clinical variables and diagnoses.

RESULTS

A total of 203 cases of epithelial SGT were included. Females were slightly more commonly (56.5%), with a mean age of 14.1 years. The palate was the most common site (43.5%), followed by the parotid gland (29%), lip (10%), and submandibular gland (7.5%). The predominant clinical presentation was a flesh-colored, smooth, and painless nodule. Pleomorphic adenoma (PA) was the most frequently diagnosed SGT (58.6%), followed by mucoepidermoid carcinoma (MEC) (26.6%). Surgery (90.8%) was the favored treatment option.

CONCLUSIONS

Benign SGT in pediatric patients are more commonly benign than malignant tumors. Clinicians should keep PA and MEC in mind when assessing nodular lesions of possible salivary gland origin in pediatric patients.

Distribution and Frequency of Salivary Gland Tumours: An International Multicenter Study

BACKGROUND

Salivary gland tumours (SGT) are a relatively rare group of neoplasms with a wide range of histopathological appearance and clinical features. To date, most of the epidemiological studies on salivary gland tumours are limited for a variety of reason including being out of date, extrapolated from either a single centre or country studies, or investigating either major or minor glands only.

METHODS

This study aimed to mitigate these shortcomings by analysing epidemiological data including demographic, anatomical location and histological diagnoses of SGT from multiple centres across the world. The analysed data included age, gender, location and histological diagnosis from fifteen centres covering the majority of the world health organisation (WHO) geographical regions between 2006 and 2019.

RESULTS

A total of 5739 cases were analysed including 65% benign and 35% malignant tumours. A slight female predilection (54%) and peak incidence between the fourth and seventh decade for both benign and malignant tumours was observed. The majority (68%) of the SGT presented in major and 32% in the minor glands. The parotid gland was the most common location (70%) for benign and minor glands (47%) for malignant tumours. Pleomorphic adenoma (70%), and Warthin's tumour (17%), were the most common benign tumours whereas mucoepidermoid carcinoma (26%) and adenoid cystic carcinoma (17%) were the most frequent malignant tumours.

CONCLUSIONS

This multicentre investigation presents the largest cohort study to date analysing salivary gland tumour data from tertiary centres scattered across the globe. These findings should serve as a baseline for future studies evaluating the epidemiological landscape of these tumours.

Giant deep lobe parotid tumor removal via total parotidectomy without mandibulotomy. A simple and safe technique

The transmandibular route is often combined with the transparotid-transcervical approach when extensive surgical field exposure is required, as in the case of deep parotid lobe tumors measuring over 4 cm in size. This procedure implies great morbidity and prolongs surgery time. Furthermore, in cases where additional lip division is performed, the aesthetic outcomes may be poorer. A description is made of the technique used for the removal of giant pleomorphic adenomas of the parapharyngeal space, without mandibulotomy.

Key words:Parapharyngeal space tumor, pleomorphic adenoma, transcervical-transparotid approach, transmandibular approach.

Clinicopathological analysis and survival outcomes of primary salivary gland tumors in pediatric patients: A systematic review

BACKGROUND

Salivary gland tumors are a diverse group of uncommon neoplasms that are rare in pediatric patients. The aim of this study was to evaluate the clinicopathological profile and survival outcomes of pediatric patients affected by salivary gland tumors.

MATERIALS AND METHODS

An extensive search was carried out using the MEDLINE/PubMed, EMBASE, Scopus databases, and grey literature. The risk of bias was available in all papers included.

RESULTS

A total of 2,830 articles were initially retrieved with 54 remaining for data extraction, resulting in 2,937 cases. This comprised forty-five case series' and nine cohort studies. These tumors were slightly more prevalent in females (57.4%). The patients' age ranged from 0.3 to 19 years old, with a mean age of 13.3 years. Parotid was the most affected site (81.9%), and 99.2% of cases clinically exhibited a swelling. Presence of pain/tenderness was reported in 13.5% of the cases, with an average duration of 12.6 months for the appearance of symptoms. Most of the reported cases were malignant tumors (75.4%), with mucoepidermoid carcinoma the most common tumor of all tumors (44.8%), followed by pleomorphic adenoma (24.1%). Surgery alone was the leading treatment choice in 74.9% cases, and the 5-year overall survival rate of patients was 93.1%. Patients with symptoms (P = .001), local recurrence (P < .001), metastasis (P < .001), and those not undergoing surgery or surgery combined with radiotherapy (P < .001) showed lower survival rates.

CONCLUSION

The pediatric patients present a high frequency of malignant salivary neoplasms and a high overall survival rate.

Risk of malignancy associated with cytomorphology subtypes in the salivary gland neoplasm of uncertain malignant potential (SUMP) category in the Milan System: A bi-institutional study

BACKGROUND

Salivary gland neoplasm of uncertain malignant potential (SUMP) is a diagnostic category in the Milan System for Reporting Salivary Gland Cytopathology. The objective of this study was to assess the risk of neoplasm (RON) and the risk of malignancy (ROM) in SUMP cases by evaluating them based on their prominent cytomorphology.

METHODS

The pathology databases were searched for cases of fine-needle aspiration-diagnosed SUMP at The Johns Hopkins Hospital and Northwestern University from 2013 to 2018. Only cytopathology cases diagnosed as SUMP that had available surgical follow-up were included.

RESULTS

Sixty-five patients with SUMP were identified, including 31 men and 34 women who ranged in age from 15 to 87 years (mean age, 55.2 years). Sixty-five cases had histologic follow-up, including 13 (20%) with basaloid features, 13 (20%) with oncocytic features, and 39 (60%) with unspecified features. No cases with clear cell features were found. Overall, the RON in the SUMP category was 95.4% (62 of 65 cases), and the ROM was 33.8% (22 of 65 cases). The RON in SUMPs with basaloid, oncocytic, and unspecified subtypes was 92.3%, 100%, and 94.9%, respectively, whereas the ROM was 38.5%, 7.7%, and 41%, respectively. The most common benign neoplasm was pleomorphic adenoma (23.1%), whereas mucoepidermoid carcinoma (9.2%) was the most common malignant neoplasm.

CONCLUSIONS

This study shows that the ROM differs significantly based on cytomorphology subtypes, whereas the overall ROM is approximately the same as the target rate in the Milan System for Reporting Salivary Gland Cytopathology. Moreover, the RON remains high in the SUMP category among different cytomorphology subtypes. Adequate sampling, immunohistochemical staining, and familiarity with metaplastic and reactive changes may improve the diagnosis.

JOURNAL CLUB: The Warthin Tumor Score: A Simple and Reliable Method to Distinguish Warthin Tumors From Pleomorphic Adenomas and Carcinomas

OBJECTIVE

The objective of this article is to propose a Warthin tumor (WT) score to distinguish WTs from other parotid tumors.

MATERIALS AND METHODS

The study included 78 patients with 92 histologically proven parotid tumors, including 42 WTs, 30 pleomorphic adenomas (PMAs), and 20 carcinomas. Echo-planar DW images were acquired. The WT score, which comprised the mean apparent diffusion coefficient (ADC_M) and the SD of the ADC (ADC_SD) of tumors, patient age, and patient sex, was used to predict WTs. The diagnostic performance of the WT score was evaluated using ROC analyses. Statistical significance was denoted by p < 0.05.

RESULTS

With the use of optimized criteria, including an ADC_M less than or equal to 1.016 × 10^-3 mm²/s (WT score, 1), an ADC_SD less than or equal to 0.1171 × 10^-3 mm²/s (WT score, 1), patient age older than 49 years (WT score, 1), and male sex (WT score, 1), a WT score greater than 2 had a sensitivity, specificity, positive negative value, negative predictive value, and accuracy of 85.7%, 100.0%, 100.0%, 89.3%, and 93.4%, respectively.

CONCLUSION

The WT score allows parotid WTs to be distinguished from PMAs and carcinomas with high accuracy.

Retrospective study of 149 cases of salivary gland carcinoma in a Spanish hospital population

Background

The clinical and histological characteristics of salivary gland tumors vary widely, complicating their diagnosis and management, and major differences have been recorded in the distribution of histopathological diagnoses among different countries.

Material and Methods

This retrospective study reviewed the demographic (age, sex) and clinicopathological (pathology diagnosis and localization) characteristics of cases diagnosed with primary SGC between June 1992 and May 2014 in the Pathology Department of the 12 de Octubre Hospital of Madrid. Diagnoses were recorded according to the 2005 WHO classification.

Results

The study included 149 SCG patients, aged between 11 and 94 yrs, with mean age at onset of 55.56 yrs and peak incidence in the eighth decade of life. The male:female ratio was 1.01. The parotid gland was the most frequently involved (75.2%). The most frequent carcinoma was mucoepidermoid carcinoma (24.2%), followed by acinic cell carcinoma (15.4%).

Conclusions

The demographic and histopathological characteristics of patients with salivary gland carcinomas in Spain, reported here for the first time, are broadly similar to those found in other countries.

Key words:Salivary gland carcinomas, descriptive, salivary glands, salivary gland tumors, head and neck cancer, oral cancer, Spain.

Histopathological diversity in parotidectomy materials in Turkish population: clinicopathologic analysis and demographic features of 136 cases in a tertiary care hospital

BACKGROUND

Salivary gland tumours, which account for approximately 3% of head-neck cancers, are a heterogeneous group and thus it is difficult to identify their epidemiological characteristics. The aim of this study is to determine demographic features and histopathologic distribution of parotid neoplasms in a large sample from Turkey.

MATERIALS AND METHODS

This study was conducted retrospectively on 136 parotidectomy materials from operations between May 2009-May 2013. Age, gender, tumor diameter, histopathological diagnosis and surgical margin status were recorded.

RESULTS

The benign cases were 112 (82.4%), while the malignancies were 24 (17.6%). The accuracy rate of FNAC was 91%. There were 46 (33.8%) male and 90 (66.2%) female patients. Female/ male ratio (M/F=0.5) was two, the Warthin (WT) tumor being more apparent in males (p<0.05). Pleomorphic adenoma (PA) was detected most frequently among benign pathologies at 61.6% (69/112), while the Warthin Tumor (WT) was detected as the second most frequent tumor at 20.5% (23/112). Mucoepidermoid carcinoma (MEC) and carcinoma ex pleomorphic adenoma (Ca ex PA) were detected at equal frequency at 20.8% (5/24) among malign tumors. These were followed by acinic cell carcinoma at 16.7% (4/24). While the surgical margin was positive in ten patients with malignant tumors (41.7%), all of the benign tumors were negative (p<0.01). No significant difference was detected in the age-gender of patients, tumor size and distribution of sites among benign and malignant groups (p>0.05).

CONCLUSIONS

Pleomorphic adenoma is the most frequently reported benign tumor almost in all global literature. Yet, the distribution of malignant tumors displays geographical differences. Based on these data, we believe that our findings will provide a significant contribution to future epidemiological studies. We think that it will be beneficial to generate awareness on parotid tumors and ensure a fight against smoking as with all head-neck cancers.