Incidence of salivary gland neoplasms in a defined UK population

Perimesencephalic subarachnoid hemorrhage as a rare delayed complication of radiation therapy in a patient with parotid basaloid squamous cell carcinoma

In this case report, we address a rare entity of parotid cancer: basaloid squamous cell carcinoma, which was surgically unresectable and had thus far only been treated with radiation therapy. Following twenty years of continuous remission, our patient presented with an acute perimesencephalic subarachnoid hemorrhage. The cause of the acute perimesencephalic subarachnoid hemorrhage was a delayed complication of radiation therapy.

Epidemiological and histopathological patterns of malignant salivary gland tumors in the Sudanese population

Background

Malignant salivary gland tumors are rare. However, their morphological overlap and difficulty to differentiate benign from malignant makes diagnosing such diseases a challenging task. Geographical variation in distribution of these diseases is well documented in the literature. This study aims to review the histological and epidemiological variations of malignant salivary gland tumors in Sudanese patients considering the new WHO 2022 classification.

Methodology

This retrospective study included malignant salivary gland tumours in our lab spanning from the period of 2014 to 2022. Information about clinical data, habits, geographical distribution, pathological diagnosis, duration and sites of tumors were retrieved from our archives. Equivocal cases were checked by a salivary gland expert. Data analysis was performed using IBM SPSS 29.

Results

This study included 107 cases of malignant salivary gland tumours, representing 54 % of the total number of salivary gland tumours in the lab during that period. 47.7 % of the patients in this study were females and 52.3 % were males, the mean age of patients was 50 ± 15.7 years. (30 %) of the patients were from the central region of the country. The most common malignant salivary gland tumor was the Mucoepidermoid carcinoma accounting for 17 %. The palate was found to be the most common site as 38 % of malignant salivary gland tumors occurred in this site.

Conclusion

The study found a high percentage of salivary gland tumours in the Sudan suggesting geographical differentiation.

Prognostic effects of previous cancer history on patients with major salivary gland cancer

OBJECTIVES

To explore the prognostic effects of previous cancer history on patients with major salivary gland cancer (SGC).

SUBJECTS AND METHODS

SGC patients with (sec-SGC) and without (one-SGC) a previous cancer from the SEER database were identified. Cox proportional hazards regression (CoxPH) models were used to compare the prognosis between sec-SGC and one-SGC patients. Subgroup analyses for sec-SGC patients by gender, previous cancer types, previous cancer histology, and cancer diagnosis interval (CDI) were performed. Two CoxPH models were constructed to distinguish sec-SGC patients with different prognostic risks.

RESULTS

9098 SGC patients were enrolled. Overall, sec-SGC patients (adjusted HR [aHR] = 1.26, p < 0.001), especially those with a CDI ≤ 5 years (aHR = 1.47, p < 0.001), had worse overall survival (OS) than one-SGC patients. In subgroup analysis, only sec-SGC patients with a previous head and neck cancer who were female (aHR = 2.38, p = 0.005), with a CDI ≤ 5 years (aHR = 1.65, p = 0.007) or with a previous squamous cell carcinoma (aHR = 6.52, p < 0.001) had worse OS. Our models successfully differentiated all sec-SGC patients into high-, intermediate- and low-risk groups with different prognosis.

CONCLUSIONS

Sec-SGC patients with different previous cancer types, gender, CDI and previous cancer histology had varied prognosis. The models we constructed could help differentiate the prognosis of sec-SGC patients with different risks.

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.

Deep learning based ultrasound analysis facilitates precise distinction between parotid pleomorphic adenoma and Warthin tumor

Background

Pleomorphic adenoma (PA), often with the benign-like imaging appearances similar to Warthin tumor (WT), however, is a potentially malignant tumor with a high recurrence rate. It is worse that pathological fine-needle aspiration cytology (FNAC) is difficult to distinguish PA and WT for inexperienced pathologists. This study employed deep learning (DL) technology, which effectively utilized ultrasound images, to provide a reliable approach for discriminating PA from WT.

Methods

488 surgically confirmed patients, including 266 with PA and 222 with WT, were enrolled in this study. Two experienced ultrasound physicians independently evaluated all images to differentiate between PA and WT. The diagnostic performance of preoperative FNAC was also evaluated. During the DL study, all ultrasound images were randomly divided into training (70%), validation (20%), and test (10%) sets. Furthermore, ultrasound images that could not be diagnosed by FNAC were also randomly allocated to training (60%), validation (20%), and test (20%) sets. Five DL models were developed to classify ultrasound images as PA or WT. The robustness of these models was assessed using five-fold cross-validation. The Gradient-weighted Class Activation Mapping (Grad-CAM) technique was employed to visualize the region of interest in the DL models.

Results

In Grad-CAM analysis, the DL models accurately identified the mass as the region of interest. The area under the receiver operating characteristic curve (AUROC) of the two ultrasound physicians were 0.351 and 0.598, and FNAC achieved an AUROC of only 0.721. Meanwhile, for DL models, the AUROC value for discriminating between PA and WT in the test set was from 0.828 to 0.908. ResNet50 demonstrated the optimal performance with an AUROC of 0.908, an accuracy of 0.833, a sensitivity of 0.736, and a specificity of 0.904. In the test set of cases that FNAC failed to provide a diagnosis, DenseNet121 demonstrated the optimal performance with an AUROC of 0.897, an accuracy of 0.806, a sensitivity of 0.789, and a specificity of 0.824.

Conclusion

For the discrimination of PA and WT, DL models are superior to ultrasound and FNAC, thereby facilitating surgeons in making informed decisions regarding the most appropriate surgical approach.

[Salivary Gland Tumors: Limitations of International Guidelines and Status of the planned AWMF-S3-Guideline]

Primary salivary gland carcinomas are not among the common head and neck tumors. They are characterized by manifold different histological types. Clinically, malignant tumors often cannot be distinguished from benign tumors, so that in these cases malignancy is only established by histopathological diagnosis. These are all reasons why there are relatively few clinical trials on the diagnosis, therapy and follow-up of these tumors. This in turn has the consequence that often only recommendations with limited evidence can be made in clinical guidelines. The most important international guidelines are the National Comprehensive Cancer Network (NCCN) guideline of 2023, the American Society of Clinical Oncology (ASCO) guideline of 2021, the European Society for Medical Oncology (ESMO) guideline of 2022 and still the British National Multidisciplinary guideline of 2016. These 4 international guidelines with their strengths and limitations are presented and commented here. Against this background, the development of a first German S3 clinical guideline on salivary gland tumors is important and expected to be completed in 2023. For the first time in the German guideline program on oncology, benign and malignant tumors are presented together in order to comprehensively do justice to the special features of salivary gland tumors.

Evaluation of the effectiveness of superficial parotidectomy and partial superficial parotidectomy for benign parotid tumours: a meta-analysis

OBJECTIVE

To quantify the results of superficial parotidectomy (SP) and partial SP (PSP) for benign parotid tumours using a systematic evaluation method.

METHODS

A systematic search of English and Chinese databases (PubMed, Web of Science, Cochrane Library, China Knowledge Network, Wanfang and Vipshop) was conducted to include studies comparing the treatment outcomes of SP with PSP.

RESULTS

Twenty-three qualified, high-quality studies involving 2844 patients were included in this study. The results of this study showed that compared to the SP surgical approach, the PSP surgical approach reduced the occurrence of temporary facial palsy (OR = 0.33; 95% confidence interval [CI] 0.26-0.41), permanent facial palsy (OR = 0.28; 95% CI 0.16-0.52) and Frey syndrome (OR = 0.36; 95% CI 0.23-0.56) in patients after surgery, and the surgery operative time was reduced by approximately 27.35 min (95% CI - 39.66, - 15.04). However, the effects of PSP versus SP on salivary fistula (OR = 0.70; 95% CI 0.40-1.24), sialocele (OR = 1.48; 95% CI 0.78-2.83), haematoma (OR = 0.34; 95% CI 0.11-1.01) and tumour recurrence rate (OR = 1.41; 95% CI 0.48-4.20) were not statistically significant.

CONCLUSION

Compared with SP, PSP has a lower postoperative complication rate and significantly shorter operative time, suggesting that it could be used as an alternative to SP in the treatment of benign parotid tumours with the right indications.

The characteristics of Polish patients with salivary gland tumors: a ten-year single-center experience

OBJECTIVES

The study aims to provide insights into the characteristics of Polish patients with different salivary gland pathologies.

MATERIALS AND METHODS

This is a retrospective study conducted at a single center, including patients who underwent surgery for salivary gland pathologies between 2012 and 2022.

RESULTS

This study included 239 patients who underwent surgery for salivary gland tumors or inflammatory diseases. Malignant tumors were diagnosed in 9.8% of participants, while 64% had benign tumors and 21% suffered from inflammation. The occurrence of complications after surgery was relatively low, with 9.9% of participants experiencing slight facial weakness or mild dysfunction, and 3% experiencing complete paralysis of the facial nerves. Significant differences were observed between patients with cancers and those with benign tumors and inflammation in terms of age. Cancers were more common in females (67% vs. 33%) and predominantly localized in the parotid glands (95%).

CONCLUSION

Benign tumors, such as Warthin's tumors and polymorphous adenoma, were predominantly found in the parotid glands of patients aged 39-72 years. On the other hand, inflammatory diseases were primarily localized within the submandibular glands of males aged 40-68 years. Additionally, the presence of a malignant tumor was associated with longer hospitalization periods related to surgery and a higher risk of severe complications.

CLINICAL RELEVANCE

This study on Polish patients with salivary gland tumors provides valuable clinical insights that can aid in diagnosis, treatment planning, patient counseling, and further research in the field of oncology. It contributes to the overall understanding of salivary gland tumors, potentially benefiting both patients and healthcare providers.

Epidemiological Profile of Salivary Gland Tumors in Southern Iranian Population: A Retrospective Study of 405 Cases

Aims

Salivary gland tumors (SGTs) are a rare and diverse group of tumors that account for 3 to 10% of all head and neck malignancies. We aimed to conduct a comprehensive epidemiological analysis of SGTs in the south of Iran and compare the findings with previous reports from Iran and other parts of the world.

Methods

Using a retrospective study, 405 patients diagnosed with SGTs were observed over an eight-year period between April 2013 and October 2021 in Shiraz, Iran. Patients' demographic and clinicopathological features were obtained from patients' records. Quantitative and descriptive data analysis was performed using SPSS software.

Results

There were 302 benign (74.5%) and 103 (25.4%) malignant SGTs. Pleomorphic adenoma and Warthin's tumors were the most common benign SGTs (70.5% and 21.5%, respectively). The most common malignant SGTs were mucoepidermoid carcinoma and adenoid cystic carcinoma (26.2% and 22.3%, respectively). There was a statistically significant association between tumor origin and its malignancy status (p < 0.001). In addition, the results indicated that benign tumors were most commonly detected in the parotid gland (p < 0.05). The benign tumors were more frequently observed among the younger population (p = 0.006).

Conclusion

In summary, the findings of the current study were mainly consistent with the previous reports from Iran and the rest of the world. Benign tumors were the most prevalent type of SGTs, and the parotid gland was the most common site. While the majority of cases that developed from the major salivary glands were benign, all the minor SGTs were malignant. Older patients were more likely to develop malignant tumors compared to younger ones. This study provides insights into the prevalence, age-related incidence, gender distribution, and geographic variation of salivary gland tumors. This can be instrumental to develop a guideline for screening, diagnosis, and determining an optimal treatment.

Cystic lesions in the salivary gland. Pitfalls to be avoided on cytology

Cystic lesions of the salivary glands are very uncommon entities. However, on occasion, some neoplasms of the salivary glands show a cystic component, which may be predominant or only partially cystic. Basal cell adenoma, canalicular adenoma, oncocytoma, sebaceous adenoma, intraductal papilloma, epithelial-myoepithelial carcinoma, intraductal carcinoma, and secretory carcinoma are such cystic entities. Cystic degeneration and necrosis, which can develop within solid tumours, represent another possibility. The ability to recognise this type of lesion is a challenge in diagnostic cytology because hypocellular fluid is frequently recovered. Furthermore, evaluating all of the differential diagnoses for cystic lesions of the salivary glands is helpful in obtaining the correct diagnosis. Herein, we evaluate the various types of cystic lesions within the salivary glands.

Contrast-Enhanced Ultrasound and Strain Elastography for Differentiating Benign and Malignant Parotid Tumors

OBJECTIVES

Preoperative differentiation between benign parotid tumors (BPT) and malignant parotid tumors (MPT) is crucial for treatment decisions. The purpose of this study was to investigate the benefits of combining contrast-enhanced ultrasound (CEUS) and strain elastography (SE) for preoperative differentiation between BPT and MPT.

METHODS

A total of 115 patients with BPT (n=72) or MPT (n=43) who underwent ultrasound (US), SE, and CEUS were enrolled. US and CEUS features and the elasticity score were evaluated. Receiver operating characteristic curve (ROC) analysis was used to assess the diagnostic performance of SE, CEUS, and SE + CEUS with respect to identifying MPT from BPT.

RESULTS

Solitary presentation, larger diameter, irregular shape, ill-defined margin, heterogeneous echogenicity, and calcification on US and higher elasticity score on SE had a significant association with malignancy. MPT also presented an unclear margin, larger size after enhancement, and "fast-in and fast-out" pattern on CEUS. The combination of SE and CEUS was effective for differentiating MPT from BPT (AUC: 0.88, 0.80-0.95), with a sensitivity of 86.0%, specificity of 88.9%, and accuracy of 87.8%, which were significantly higher than the values for SE (AUC: 0.75, 0.66-0.85) and CEUS (AUC: 0.82, 0.73-0.91) alone.

CONCLUSION

The combination of CEUS and SE is valuable for distinguishing MPT from BPT.

A Review of the Current Literature on Pleomorphic Adenoma

Pleomorphic adenomas (PA) are the most common benign salivary gland tumors. They arise from the major salivary glands, as well as the minor salivary glands. They may arise rarely from the palate, oral cavity, neck, and nasal cavity also. Yet, the fourth, fifth, and sixth decades of life are the most common for them to manifest. Forty percent of them occur in males and 60% in females. It is a benign mixed tumor, which has three components: an epithelial component, a myoepithelial cell component, and a mesenchymal component. A fibrous capsule separates these cells from the surrounding tissues. It generally presents as a slowly progressing painless swelling, which is well-delineated, nonsymptomatic, and not involving the facial nerve. Salivary gland tumors can be accurately diagnosed before surgery using fine-needle aspiration (FNA), ultrasonography (USG), and computed tomography (CT) scan. Calponin, cluster of differentiation 9 (CD9), glial fibrillary acidic protein (GFAP), Mcl-2, metastasis suppressor gene (NM23), p63, S-100, smooth muscle actin (SMA), and SRY-box transcription factor 10 (SOX10) exhibit the majority of the positive reactions in pleomorphic adenomas. The diagnostic marker pleomorphic adenoma gene 1 (PLAG1) is frequently employed since it is specific for pleomorphic adenoma. Although benign, these epithelial tumors have a propensity to recur and undergo malignant transformation if incompletely excised, leading to increased morbidity in these patients. A review of the consensus guidelines and literature was conducted, and the online literature on the subject from 2002 was included. This article is not a complete review of all the available literature; rather, it is a comprehensive review of the topic.

Epidemiology, outcomes, and prognostic factors in submandibular gland carcinomas: a national DAHANCA study

PURPOSE

The aim of this study is to present incidence, histological subtypes, survival rates, and prognostic factors based on a national cohort of patients with salivary gland carcinoma.

METHODS

All Danish patients with submandibular gland carcinoma diagnosed from 1990 to 2015 (n = 206) were included and analyzed following histological re-evaluation. Data were collected by the Danish Head and Neck Cancer Group (DAHANCA). Overall, disease-specific and recurrence-free survival were evaluated. Prognostic factors were analyzed with multivariate Cox Hazard Regression.

RESULTS

The study population consisted of 109 (53%) men and 97 (47%) women, median age 62 years (range 11-102). Adenoid cystic carcinoma was the most frequent subtype (50%). Tumour classification T1/T2 (75%) and N0 (78%) was most frequent. The mean crude incidence was 0.17/100,000/year. Most patients (n = 194, 94%) were treated with primary surgery, and 130 (67%) received postoperative radiotherapy. The 5- and 10-year survival rates were for overall survival 64% and 41%, disease-specific survival 74% and 61%, and recurrence-free survival 70% and 56%, respectively. Survival rates were higher for adenoid cystic carcinoma compared to other subtypes, but the difference was not significant in multivariate analysis. Recurrence occurred in 69 patients, and 37 (53.6%) of them had recurrence in a distant site. Advanced T-classification and regional lymph-node metastases had significant negative impact on survival rates.

CONCLUSION

The incidence of submandibular gland carcinoma in Denmark was 0.17/100,000/year and stable during the time period. The most frequent subtype was adenoid cystic carcinoma. Half of the recurrences presented in a distant site, and multivariate analysis confirmed that advanced stage was independent negative prognostic factor for recurrence and survival.

Comparative analysis of benign and malignant parotid gland tumors: A retrospective study of 992 patients

OBJECTIVE

We analyzed and compared the clinical characteristics of benign and malignant parotid gland tumors.

PATIENTS AND METHODS

A total of 992 patients who underwent surgical treatment for parotid gland tumors from January 2010 to December 2020 were included in this study. This study population was subdivided into benign (n = 812, 81.9 %) and malignant parotid gland tumors (n = 180, 18.1 %).

RESULTS

Pleomorphic adenoma is the most common benign tumor and mucoepidermoid carcinoma is the most common malignant tumor. The patients with malignant parotid gland tumors were older than the patients with benign lesions. The duration of symptoms was longer in patients with benign parotid gland tumors compared to those with malignant lesions. The size of the malignant tumors was larger than that of the benign lesions. Preoperative fine-needle aspiration cytology had a diagnostic sensitivity of 50.3 %, diagnostic specificity of 98.7 %, a positive predictive value of 89.5 %, a negative predictive value of 89.9 %, and accuracy of 89.9 % for diagnosing malignant parotid gland tumors. For benign parotid gland tumors, superficial parotidectomy was most frequently performed, and for malignant parotid gland tumors, total parotidectomy was most frequently performed. Facial palsy was observed in 19.4 % of the patients with malignant parotid gland tumors compared to 5.4 % of those with benign tumors.

CONCLUSION

The clinical features of benign and malignant parotid gland tumors showed differences in age, symptoms, duration of symptoms, size and site of the parotid tumors, surgical procedures, and postoperative facial nerve palsy.

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.

Facial nerve dysfunction following parotidectomy: role of intraoperative facial nerve monitoring

PURPOSE

Facial nerve dysfunction (FND) is a frequent and serious parotidectomy outcome. Intraoperative facial nerve monitoring (IFNM) is an increasingly used technique to identify the facial nerve (FN) and minimize its injury. This study aimed to evaluate the determinant factors in the presence and severity of FND after parotidectomy, including IFNM.

STUDY DESIGN, SETTING AND METHODS

A total of 48 patients consecutively submitted to parotidectomy between 2005 and 2020 in a tertiary hospital were retrospectively analyzed. The House-Brackmann Scale (HBS) was used to assess the severity of FND.

RESULTS

There was a mean age of 54.2 ± 17.8 years, 50% were male. Pleomorphic adenoma (41.7%) and Warthin's tumor (25.0%) were most common. From the 23 patients (47.9%) who developed some degree of FND (HBS score of 3.41 ± 1.53), 19 (82.6%) showed facial movement recovery, with a mean recovery time of 4.78 ± 2.53 months. IFNM was performed in 39.6% of the surgeries. The use of IFNM (p = 0.514), the type of surgery-partial or total parotidectomy-(p = 0.853) and the type of histology-benign or malignant lesion-(p = 0.852) did not significantly influence the presence of FND in the postoperative period. However, in the subgroup of patients who developed FND, the HBS value was significantly lower in cases of benign pathology (p = 0.002) and in patients who underwent IFNM (p = 0.017), denoting a significantly lower severity.

CONCLUSION

In the present study, IFNM and the existence of a benign lesion have been shown to be associated with lower severity of FND.

Trend changes in the incidence of benign parotid tumours in the last 30 years in a Spanish population

PURPOSE

To study the demographics and clinical characteristics of benign parotid tumours, focusing on the evolution of the incidence of Warthin tumour (WT) in recent years.

METHODS

A retrospective observational study is designed of patients diagnosed with a benign parotid tumour in a single tertiary hospital centre, from 1994 to 2021. The evaluation of the relationship between the different variables, and the changes in tumour incidence, is carried out using an analysis of standardized residuals.

RESULTS

The study evaluated 279 patients, and the total of benign parotid tumours was 291. The most frequent type of tumour was pleomorphic adenoma (PA) (52.7%), followed by WT (37.6%). WT was more frequent in men (79%), and PA in women (55.8%). Smoking history is significantly high in patients with WT (83%), as well as mid-age, compared to PA.

CONCLUSIONS

It seems to be an increase in the proportion of WT compared to PA in recent years. These changes can be concerning tobacco use and older patients at diagnosis in our series.

Tumor-to-tumor metastasis to Warthin tumor presenting as an initial sign of breast carcinoma: A case report

Metastases of distant primary tumors on the parotid gland are very rare. Tumor-to-tumor metastasis to salivary gland tumors is extremely rare. A case of a 69-year-old woman with a large left parotid gland mass with no previous salivary gland problems or cancer. Fine-needle aspiration (FNA) showed evidence of a Warthin tumor. A total left parotidectomy was performed. The final pathology report showed a Warthin tumor containing two metastases of adenocarcinoma. The immunohistochemistry of the metastases led to the diagnosis of primary breast cancer. A negative FNA does not rule out the possibility of a malignant parotid tumor or metastasis, and a parotid lump should be presumed to be a secondary tumor until proven otherwise if the patient has a history of any distant primary cancer. Our patient case serves as a reminder that a new distant primary cancer might be the cause of a parotid lump.

Salivary gland tumours: an epidemiological review of non-neoplastic and neoplastic pathology

Salivary gland tumours (SGT) demonstrate geographical variation. The primary objective of this study was to determine the types, frequency, distribution, and demographics of non-neoplastic and neoplastic salivary gland pathology at Waikato Hospital, New Zealand (NZ) over a 10-year period. Following this we conducted a 10-year retrospective review of SGT epidemiology from international literature. In total 825 patients were identified, 31% (256/825) with non-neoplastic salivary gland pathology, 34% (284/825) with benign neoplastic pathology, 14% (118/825) with primary malignant lesions, 18% (146/825) with metastatic SGTs, and 3% (21/825) with lymphoma. Patients had a mean (range) age of 58 (3-102) years, were predominantly male (58%, 476/825), and NZ European (65%, 536/825). Tumours were most prevalent in the parotid gland (85%, 484/569), of which 44% (211/484) were malignant. Pleomorphic adenoma was the most common benign (71%, 203/284) and overall (36%, 203/569) tumour, while mucoepidermoid carcinoma (25%, 29/118) and squamous cell carcinoma (SCC) (73%, 106/146) were the most common primary malignant and metastatic SGTs, respectively. Our literature review identified 18 studies consisting of 33,933 patients, of whom 71% (24,013/33,933) had benign SGTs. Pleomorphic adenoma (68%, 16404/24013) and mucoepidermoid carcinoma (29%, 2826/9621) were the most common benign and malignant SGTs, respectively. Low numbers of non-neoplastic and metastatic SGTs were reported in the literature. This research provides a greater understanding of differences in their global distribution. Consistent with previous literature, pleomorphic adenoma and mucoepidermoid carcinoma were the most common benign and malignant SGTs. In NZ, we found high rates of malignant SCC to the parotid gland, consistent with the epidemiology of non-melanoma skin cancer in the country.

Pre-treatment quality of life in patients with salivary gland cancer in comparison with those of head and neck cancer patients

INTRODUCTION

Salivary gland cancer (SGC) is a rare malignant tumor arising from the salivary glands, with a variety of clinical and biological behaviors different from head and neck cancer (HNC). Because of the rarity of SGC, there are limited data on pre-treatment quality of life (QoL). Therefore, we evaluated the pre-treatment QoL in SGC patients by stage and compared it with that of HNC patients.

METHODS

From a prospective registry of HNC patients (2016-2020), we selected 225 patients with SGC, and 912 patients with oral cavity (OC) and oropharyngeal cancer (OPC) who were diagnosed in the same period as the HNC control group. The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) and HNC-Specific Module (H&N35) were used to assess QoL.

RESULTS

SGC patients had a statistically better baseline QoL (69.8 vs. 64.0), emotional (82.1 vs. 78.8), cognitive (92.0 vs. 88.7), and social function (86.3 vs. 80.5), and fewer symptoms than HNC patients. The estimated average QoL differences between SGC patient diagnosed at stages I and IV was -12.9. Especially, advanced-stage of tumors was associated with much lower role functioning and emotional functioning scores in SGC patients, compared to those in HNC patients, among females and of younger age.

DISCUSSION

Although the overall QoL score was higher in SGC patients than in HNC patients, specific domains were significantly affected in SGC patients according to the tumor stage. Females and those of younger age were more affected by severity of disease in SGC.

STUDY REGISTRATION

ClinicalTrials.gov Identifier NCT02546895.

Salivary gland cancer: ESMO-European Reference Network on Rare Adult Solid Cancers (EURACAN) Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO–EURACAN Clinical Practice Guideline provides key recommendations for managing salivary gland cancer. •The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. •Treatment algorithms for parotid, submandibular, sublingual and minor salivary gland cancer are provided. •The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe. •Recommendations are based on available scientific data and the authors’ collective expert opinion.

Reliability of the 'M-Line' in the Prediction of the Facial Nerve Position in Patients with Parotid Neoplasms

Preoperative radiological assessment of parotid tumours represents a crucial step in the planning of a parotidectomy in order to avoid post-operative facial nerve paralysis. The purpose of this study is to determine the reliability of the novel 'M-line' in predicting the facial nerve position and compare it to various radiological methods in the same context. 66 patients whom had underwent parotidectomy for parotid tumours from January 2012 to February 2021 were analyzed. Parotid tumour location were identified using the retromandibular vein, facial nerve line, Conn's arc, Utrecht line and the 'M'-line were compared to the intraoperative location of parotid tumours.The 'M'-line is a novel hypothetical line (drawn between the lateral surface of the mandible to the lateral border of the mastoid process) used to identify the location of the facial nerve radiologically. The 'M-Line' and other methods of radiological assessments were associated with statistical significance in predicting if the parotid tumours were superficial or deep to the facial nerve (p-value < 0.05).The 'M-line' had demonstrated a sensitivity of 73.6% and 92.3% specificity.It had also yielded the highest accuracy (77.3%) in the prediction of the parotid tumour location in relation to the facial nerve. While the radiological lines represented by the Retromandibular vein,facial nerve line,Utrecht line and Conn's arc were statistically significant in predicting the location of the parotid tumour in relation to the facial nerve, the M-line was the most accurate and sensitive predictor in our study.The M-Line is a potentially useful tool to predict the location of the facial nerve in relation to a parotid tumour.

Minimal Margin Surgery and Intraoperative Neuromonitoring in Benign Parotid Gland Tumors: Retrospective Clinical Study

Extracapsular dissection (ECD) was introduced for the removal of superficial and small benign parotid tumors. According to a recent proposal, ECD is reserved for tumors that are 3 cm or less, mobile, and close to the parotid borders in cases of pleomorphic adenoma. The aim of the study is to evaluate the effectiveness of ECD for treatment of benign parotid tumors also in cases of tumors that were larger than 3 cm and deeper. All ECD for benign parotid neoplasms conducted between 2007 and 2017 were reviewed. The lesions included were limited to primary parotid tumors and categorized by Quer proposal. Facial nerve monitoring was used in all cases. Facial nerve palsy and local recurrences were assessed. The 88 ECD performed met inclusion criteria. The mean lesion size was 4.26 cm. Of the tumors, 68 were less than 3 cm in diameter and 20 were larger, 64 were superficial, and 24 were deep. The most common lesion types were pleomorphic adenoma (88.6%). There was no significant difference in complication rates between the size of tumor (p = 0.9) and location (p = 0.91). Our results suggest that extracapsular dissection could be considered an option for first-time diagnosed benign parotid tumors, even in cases of large dimensions and deep lobe involvement.

Triple Assessment of a Palpable Parotid Lump in "One-Stop" Clinics

Introduction

The National Institute of Clinical Excellence in the UK (NICE) recommended the use of "one-stop" clinics for the assessment and management of head and neck lumps like those established for breast lumps. "One-stop" clinics should follow a triple assessment protocol involving physical examination, radiological imaging and fine-needle aspiration cytology (FNAC).

Methods

A retrospective analysis of 144 patients with suspected parotid tumours from 2005 to 2011 was done. Patients were assessed for individual modalities and compared against the final histological diagnosis. Statistical analysis was used for sensitivity and specificity, as well as positive and negative predictive values. All calculations were performed using SPSS version 16 (Statistical Packages for the Social Sciences, Chicago, IL). A p value of < 0.05 was considered to indicate statistical significance.

Results

A total of 105 patients underwent all the three modalities. Out of them, 93 had imaging that was considered radiologically benign and 12 were reported to have a malignant lesion. Cytologically, 75 were found to have a benign tumour, 13 were malignant, and 17 were considered to be indeterminate. The most common benign neoplasm was pleomorphic adenoma followed by Warthin's tumour. The sensitivity and specificity of triple assessment were 96% (p value 0.878-0.984) and 73% (p value 0.42-0.904), respectively. The positive predictive value was 96% (p value 0.878-0.984) and negative predictive value came out to be 93% (p value 0.42-0.904).

Conclusions

The overall accuracy of triple assessment was found to be 92%. This study concludes that triple assessment is a useful assessment tool to evaluate a patient with parotid lump.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-021-01590-5.

Comparison of various surgical incisions in parotidectomy: A systematic review and network meta-analysis

Background

This network meta-analysis aimed to comprehensively compare the operative and postoperative outcomes of different parotidectomy incisions.

Methods

Embase, PubMed, Web of Science, and Cochrane Central Register of Controlled Trials were searched up to April 2022. A complete Bayesian network meta-analysis was performed using the Markov Monte Carlo method in OpenBUGS.

Results

Seventeen studies with 1609 patients were included. Thirteen were retrospective cohort studies, three were prospective cohort studies, and one was a randomized controlled study. The quality of evidence was rated as very low in most comparisons. The incision satisfaction score of the modified facelift incision (MFI), retroauricular hairline incision (RAHI), V-shaped incision (VI) were higher than that of the modified Blair incision (MBI) (MBI vs. MFI: mean difference [MD] -1.39; 95% credible interval [CrI] -2.23, -0.57) (MBI vs. RAHI: MD -2.25; 95% CrI -3.40, -1.12) (MBI vs. VI: MD -2.58; 95% CrI -3.71, -1.46); the tumor size treated by VI was smaller than that by MBI (MD 5.15; 95% CrI 0.76, 9.38) and MFI (MD 5.16; 95% CrI 0.34, 9.86); and the risk of transient facial palsy in the MFI was lower than that in the MBI (OR 2.13; 95% CrI 1.28, 3.64). There were no differences in operation time, drainage volume, wound infection, hematoma, salivary complications, Frey syndrome, or permanent facial palsy between incision types.

Conclusion

The traditional MBI is frequently used for large tumor volumes, but the incision satisfaction score is low and postoperative complication control is poor. However, emerging incisions performed well in terms of incision satisfaction scores and control of complications. More randomized controlled trials are needed to compare the different parotidectomy incisions. Patients should be fully informed about the characteristics of each incision to make the most informed decision, along with the physician’s advice.

Systematic Review Registration

PROSPERO, identifier CRD42022331756

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.

Hyalinizing Clear Cell Salivary Gland Carcinoma of the Epipharynx: A Minor Salivary/Tubarial Gland Malignancy

Minor salivary gland malignancies are a rare entity among head and neck tumors. As in major gland neoplasms, adenoid cystic carcinoma and mucoepidermoid carcinoma are the most common histological subtypes. Malignant tumors affecting minor salivary glands include a wide range of histopathologic types. Localization in the epipharynx and hyalinizing clear cell carcinoma subtype are exceedingly rare. A 47 year-old male presented to our clinic with a complaint of slowly progressing left-sided nasal obstruction. Endoscopy revealed a well-defined nodular epipharyngeal mass. Radiographic evaluation discovered a nonvascularized tumor of the tubal protuberance. The tumor was treated with wide local excision. Staging at the time found no evidence of regional lymph node metastases. Histologic examination revealed a hyalinizing clear cell salivary gland carcinoma demonstrating an EWSR1-ATF1 gene fusion. Restaging endoscopy and radiographic imaging 3 months after initial therapy did not reveal any signs of tumor persistence. The patient is currently in follow-up.

Management of malignant submandibular gland tumors: A 30-year experience from a single center

OBJECTIVE

Owing to histologic heterogeneity, biological behavior, and rarity, recommendations for the treatment of malignant submandibular gland tumors (MSGT) are inconsistent. The aim of this study was to present a single-center experience in the treatment of MSGT with an emphasis on surgical treatment, including indication on elective neck dissection (END).

STUDY DESIGN

Twenty-four MSGT were primary surgically treated (gland excision with neck dissection). Their records were retrospectively collected and analyzed.

RESULTS

The most frequent histology was adenoid cystic carcinoma (41.6%), followed by mucoepidermoid carcinoma (25%) and carcinoma ex pleomorphic adenoma (16.7%). There were 18 elective and 6 therapeutic neck dissections. Histopathologic examination confirmed 29% (7/24) of positive neck dissection specimens. The Kaplan-Meier analysis presented rates of disease-specific survival, disease-free survival, and overall survival (OS) of 81%, 78%, and 52% at 5 years, respectively. Patients undergoing postoperative radiotherapy had significantly higher OS rates compared with patients treated with surgery alone (P = .0209).

CONCLUSION

Results of this study suggest that END has questionable benefit in early stage MSGT. Elective selective neck dissection levels I-III is recommended in high-grade and advanced stage MSGT without evidence of multilevel lymphadenopathy.

Ultrasound-guided core biopsy in the diagnosis of parotid neoplasia: an overview and update with a review of the literature

OBJECTIVE

Accurate diagnosis of parotid neoplasia is a key to determine the most appropriate patient management choice, including the need for surgery. This review provides an update of the literature on current practice and outcomes of parotid tissue sampling techniques, with an emphasis on ultrasound-guided core biopsy (USCB) and comparison with fine needle aspiration cytology (FNAC).

METHODS

A literature review of EMBASE, Medline, PubMed and Google Scholar was conducted.

RESULTS

USCB has higher sensitivity, specificity and lower non-diagnostic rates than optimized FNAC. It also has a significantly higher sensitivity for the detection of malignancy. Significant complications post-USCB are uncommon, with only one reported case of tumour seeding and no cases of permanent facial nerve dysfunction. The technique is less operator-dependent than FNAC, with less reported variation in results between institutions.

CONCLUSIONS

USCB can be considered as the optimum tool of choice for the diagnosis of parotid neoplasia. This would particularly be the case in centres utilizing FNAC with high non-diagnostic rates or reduced diagnostic accuracy when compared to USCB published data, or in centres establishing a new service.

ADVANCES IN KNOWLEDGE

An update of the role and outcomes of USCB in the diagnosis of parotid gland pathologies.Research shows that USCB preforms better than FNAC, in terms of sensitivity and specificity, particularly in the case of malignant neoplasia.Complications following USCB were found to be higher than that of FNAC; however, no long-term major complications following either method have been reported in the literature.

An institutional review of recurrent pleomorphic adenoma of the parotid gland

OBJECTIVE

Surgical resection is standard treatment for pleomorphic adenoma (PA) of the parotid gland. A small number (2-5%) of these tumors recur. Recurrence usually necessitates reoperation, which is technically challenging and puts the facial nerve (FN) at risk. The aim of this study is to characterize the recurrent parotid PA population and compare outcomes after surgery for singly recurrent and multiply recurrent tumors.

METHODS

This study was a retrospective chart review of patients at a single tertiary care academic medical center who underwent operations for recurrent PA of the parotid gland between 2007 and 2020. Demographic data, details of surgical interventions, pre- and postoperative FN function, and recurrence rates were studied. These factors were compared between patients with singly and multiply recurrent tumors.

RESULTS

Thirty-eight patients met criteria: 4 patients presented for primary PA and subsequently recurred, 26 with a first recurrence, 7 with a second recurrence, and 1 with a fourth recurrence. Multiply recurrent PAs were more likely to require at least partial nerve sacrifice at the time of reoperation (P = 0.0092). Significantly worse long-term FN outcomes were seen following surgery for multiply recurrent PA (P = 0.008). There was no significant difference between the rate of re-recurrence following first revision surgery vs second-fourth revision surgery. Time to reoperation was significantly shorter between the first and second revision surgery than between the primary surgery and first revision (P = 0.0017).

CONCLUSION

Surgery for recurrent PA incurs high risk to the FN, and this risk appears to increase in the setting of multiple recurrences.

Results of histopathological revisions of major salivary gland neoplasms in routine clinical practice

AIMS

Salivary gland neoplasms are rare and are characterised by overlapping histopathological aspects. Therefore, the assessment of the correct histopathological diagnosis can be challenging. This study evaluated the frequency of pathology consultations and revisions for salivary gland neoplasms during routine clinical practice in the Netherlands. Furthermore, the concordance and discordance rates of these revisions are presented.

METHODS

The Dutch Pathology Registry (PALGA) was searched for patients that underwent a resection of a major salivary gland neoplasm between 2006 and 2016. Frequencies of pathology consultations and revisions are presented and, in order to calculate the rates of concordance and discordance, the results of the initial histopathological review were compared with the results of the revision.

RESULTS

Between 2006 and 2016, 13 441 major salivary gland neoplasms were resected in the Netherlands. 90% (n=12 082) of these tumours were diagnosed as benign and 10% (n=1359) as malignant. The initial pathologist requested a consultation in 3.3% of resections (n=439). Revision of the histopathological specimen was performed in 2.6% (n=350) of cases. Revisions were discordant in 8.3%; including 5.8% of the initially benign diagnosed lesions reclassified as malignant by the second expert pathologist and 8% of the revised malignant tumours that underwent a subtype change.

CONCLUSIONS

The number of discordant histopathological revisions (8.3%) emphasises the complexity of the histopathological diagnosis of salivary gland neoplasms. An increase in consultations may improve the accuracy of the initial diagnosis and thus treatment in salivary gland tumours while lowering the need for revisions and the number of discordant revisions.

The Epidemiology of Salivary Glands Pathologies in Adult Population over 10 Years in Poland-Cohort Study

Background: The aim of this study was a comprehensive analysis of the incidence of different salivary gland pathologies in the adult population of Poland. Methods: A retrospective analysis of salivary gland pathologies diagnosed in Poland in 2010–2019 based on the National Health Fund (NHF) database was performed. Non-neoplastic diseases, and benign and malignant lesions were identified using ICD-10 codes. Demographic characteristics, incidence rates, and the number of inpatient and outpatient medical services were analyzed. Results: Salivary gland pathologies were diagnosed in 230,589 patients over 10 years (85.5% were non-neoplastic lesions, 11.53% benign and 2.93% malignant neoplasms). Incidence rate for all pathologies was 59.94/100,000. The mean incidence for malignant neoplasms was 1.78, and decreasing trend was observed over the analyzed period. Contrarily, for benign neoplasms (mean incidence—6.91), an increase in numbers was noted annually. The incidence for non-malignant lesions was quite stable (mean: 51.25) over the time. The highest number of medical services per patient concerned malignant neoplasms (on average, two hospital stays, and eleven outpatient consultations). Conclusions: An increase of benign salivary gland tumors, and a decrease of malignant neoplasms was observed during the studied period. The number of medical services related to salivary gland pathologies increased during the period under study.

Validation of the Milan System for Reporting Salivary Gland Cytopathology and the diagnostic accuracy of FNA cytology for submandibular gland lesions

BACKGROUND

The Milan System for Salivary Gland Cytopathology (MSRSGC) is a categorical system for salivary gland fine-needle aspiration cytopathology (FNAC) developed to aid clinicians in the management of salivary gland lesions. This classification is widely studied and validated, especially in cohorts that consist of mostly parotid gland lesions. However, only sparse literature describes the use of this classification for submandibular gland lesions in particular.

METHODS

All patients in the Netherlands that underwent a submandibular gland resection between January 1, 2006, and January 1, 2017, with a FNAC before resection were identified with the use of the Dutch Pathology Registry database (PALGA). All FNAC results were retrospectively classified according to the MSRSGC. The risk of malignancy was calculated for all the MSRSGC categories. The sensitivity and specificity of the MSRSGC classification were calculated for submandibular gland FNAC.

RESULTS

A total of 837 patients who underwent 975 FNAC aspirates from the submandibular glands were included in the analysis. Risks of malignancy for each of the MSRSGC categories were 14.4% in nondiagnostic, 4.4% in nonneoplastic, 37.0% in atypia of unknown significance, 3.9% in benign neoplasms, 40.7% in salivary gland neoplasms of unknown malignant potential, 76.2% in suspected malignant, and 91.3% in malignant cytology results. The sensitivity for diagnosing malignant submandibular gland tumors was 71.6% and specificity was 98.4%.

CONCLUSIONS

The results of the present study validate the use of this classification for submandibular gland lesions. Risks of malignancy vary according to the anatomical subsites of the salivary gland lesions.

LAY SUMMARY

The risks of malignancy of the various Milan System for Salivary Gland Cytopathology (MSRSGC) categories vary according to the anatomical subsite of the salivary gland lesion. The proposed management techniques of the MSRSGC are valid for use with submandibular gland lesions.

Mucoepidermoid carcinoma: Evaluating the prognostic impact of primary tumor site

Mucoepidermoid carcinoma (MEC) is one of the most common salivary gland malignancies. Our aim was to evaluate the prognostic impact of primary tumor site in patients with MEC.

MATERIAL AND METHODS

This cohort identified 308 patients with MEC who underwent primary surgery between 1985 and 2015. Survival outcomes were determined using the Kaplan-Meier method. Hazard ratios for primary site were determined using the Cox proportional-hazards model.

RESULTS

One hundred eighty (58%) patients were diagnosed with minor and 128 (42%) with major salivary gland cancer. Primary site in the minor salivary gland group included 137 (44%) oral cavity, 38 (12%) pharynx, 3 (0.9%) nasal cavity, and 2 (0.6%) trachea and larynx. The major salivary gland group included 118 (38%) parotid, 8 (3%) submandibular, and 2 (0.6%) sublingual. With a median follow-up of 73 months, 5-year overall survival and disease-specific survival were 84% and 91%, respectively. Patients with tumors located in the hard palate and retromolar trigone had the best survival, while patients with tumors located in the paranasal sinuses and submandibular gland had the poorest survival. After controlling for tumor grade and stage, MEC primary site was not predictive of survival or recurrence. On multivariate analysis, worse DSS was associated with stage III-IV tumors (HR: 7,11; 95% CI: 1.19-26.43; p = 0.0034) and high-grade tumors (HR: 19.12; 95% CI: 2.26-162.77; p = 0.0068).

CONCLUSIONS

While high grade and advanced overall stage were found to be independent predictors of worse survival, primary tumor site was not predictive of poor outcome.

Lymph node ratio as a predictor for minor salivary gland cancer in head and neck

Background

We investigate whether pathological continuous variables of lymph nodes were related with survival results of carcinomas of minor salivary gland carcinoma in head and neck.

Methods

Forty-four cases with minor salivary gland carcinoma who underwent both primary resection and neck dissection were retrospectively enrolled. The pathological continuous variables were evaluated by the number of positive lymph nodes, lymph node ratio, and log odds of positive lymph nodes. Receiver operating curve analysis was used for the cut-off values of the carcinoma-specific death. Log-rank test and Cox’s proportional hazards model were used for uni−/multi-variate survival analyses adjusting for pathological stage, respectively.

Results

Lymph node ratio = 0.05 as well as log odds of positive lymph nodes = − 2.73 predicted the carcinoma-specific death. Both lymph node ratio and log odds of positive lymph nodes were significantly related with survival outcomes by the univariate analysis. Lymph node ratio ≥ 0.05 was associated with shorter disease-specific (hazard ratio = 7.90, 95% confidence interval = 1.54–57.1), disease-free (hazard ratio = 4.15, 95% confidence interval = 1.48–11.2) and overall (hazard ratio = 4.84, 95% confidence interval = 1.05–24.8) survival in the multivariate analysis.

Conclusion

A higher lymph node ratio of minor salivary gland carcinoma is a predictor of shorter survival results.

Diagnostic performance of qualitative and radiomics approach to parotid gland tumors: which is the added benefit of texture analysis?

OBJECTIVE

To investigate whether MRI-based texture analysis improves diagnostic performance for the diagnosis of parotid gland tumors compared to conventional radiological approach.

METHODS

Patients with parotid gland tumors who underwent salivary glands MRI between 2008 and 2019 were retrospectively selected. MRI analysis included a qualitative assessment by two radiologists (one of which subspecialized on head and neck imaging), and texture analysis on various sequences. Diagnostic performances including sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) of qualitative features, radiologists' diagnosis, and radiomic models were evaluated.

RESULTS

Final study cohort included 57 patients with 74 tumors (27 pleomorphic adenomas, 40 Warthin tumors, 8 malignant tumors). Sensitivity, specificity, and AUROC for the diagnosis of malignancy were 75%, 97% and 0.860 for non-subspecialized radiologist, 100%, 94% and 0.970 for subspecialized radiologist and 57.2%, 93.4%, and 0.927 using a MRI radiomics model obtained combining texture analysis on various MRI sequences. Sensitivity, specificity, and AUROC for the differential diagnosis between pleomorphic adenoma and Warthin tumors were 81.5%, 70%, and 0.757 for non-subspecialized radiologist, 81.5%, 95% and 0.882 for subspecialized radiologist and 70.8%, 82.5%, and 0.808 using a MRI radiomics model based on texture analysis of T₂ weighted sequence. A combined radiomics model obtained with all MRI sequences yielded a sensitivity of 91.5% for the diagnosis of pleomorphic adenoma.

CONCLUSION

MRI qualitative radiologist assessment outperforms radiomic analysis for the diagnosis of malignancy. MRI predictive radiomics models improves the diagnostic performance of non-subspecialized radiologist for the differential diagnosis between pleomorphic adenoma and Warthin tumor, achieving similar performance to the subspecialized radiologist.

ADVANCES IN KNOWLEDGE

Radiologists outperform radiomic analysis for the diagnosis of malignant parotid gland tumors, with some MRI qualitative features such as ill-defined margins, perineural spread, invasion of adjacent structures and enlarged lymph nodes being highly specific for malignancy. A radiomic model based on texture analysis of T₂ weighted images yields higher specificity for the diagnosis of pleomorphic adenoma compared to a radiologist non-subspecialized in head and neck radiology, thus minimizing false-positive pleomorphic adenoma diagnosis rate and reducing unnecessary surgical complications.

Predictors of Sialocele or Salivary Fistula After Partial Superficial Parotidectomy for Benign Parotid Tumor: A Retrospective Study

PURPOSE

Partial superficial parotid (PSP) resection is the mainstay of treatment for benign parotid tumor. Unfortunately, the post-surgical formation of sialocele or salivary fistula is a well-recognized complication of parotid surgery. The aim of this study was to determine the predictors of sialocele or salivary fistula after PSP resection for parotid benign tumor.

METHODS

This retrospective cohort study includes patients who underwent PSP resection for benign parotid tumors from January 1, 2015 to December 31, 2019. The predictor variables were demographic data, systemic disease, smoking history, tumor size and type, surgical approach, and area. The outcome variables were the occurrence of sialocele or salivary fistula after PSP resection. Each possible risk factor was then examined using univariate analysis. Variables associated with sialocele or salivary fistula in the univariate analysis were then included in a multiple logistic regression model, and analyzed for possible factors related to the occurrence of sialocele or salivary fistula after partial superficial parotid resection.

RESULTS

The sample was composed of 872 subjects with a mean age of 51.0 ± 8.3, and 59.5% were male. The frequency of sialocele or salivary fistula after partial superficial parotid resection was 10.4% (n = 92). Based on the multiple logistic regression model, hypertension and location of the lesion were associated with sialocoele formation. Hypertension was associated with a decreased risk for the formation of sialocele or salivary fistula (ORs = 0.6, 95% CI = [0.4,1.003], P = .051). When compared the superior lesions, anterior lesions were associated with a decreased risk for the formation of sialocele or salivary fistula (ORs = 0.32, 95% CI = [0.111,0.92], P = .034) and lesions in the middle were associated with an increased risk for sialocele or salivary fistula development (ORs = 2.315,95% CI = [1.199,4.469], P = .012).

CONCLUSIONS

The incidence of sialocele or salivary fistula development was 10.4% in patients undergoing partial superficial parotidectomy in this study. Moreover, middle and anterior tumor location was shown to increase sialocele or salivary fistula risk.

Pilot study on the value of Raman spectroscopy in the entity assignment of salivary gland tumors

Background

The entity assignment of salivary gland tumors (SGT) based on histomorphology can be challenging. Raman spectroscopy has been applied to analyze differences in the molecular composition of tissues. The aim of this study was to evaluate the suitability of RS for entity assignment in SGT.

Methods

Raman data were collected in deparaffinized sections of pleomorphic adenomas (PA) and adenoid cystic carcinomas (ACC). Multivariate data and chemometric analysis were completed using the Unscrambler software.

Results

The Raman spectra detected in ACC samples were mostly assigned to nucleic acids, lipids, and amides. In a principal component-based linear discriminant analysis (LDA) 18 of 20 tumor samples were classified correctly.

Conclusion

In this proof of concept study, we show that a reliable SGT diagnosis based on LDA algorithm appears possible, despite variations in the entity-specific mean spectra. However, a standardized workflow for tissue sample preparation, measurement setup, and chemometric algorithms is essential to get reliable results.

Salivary Gland Cancers

Salivary gland carcinomas are a rare and heterogenous group of cancers with varying underlying biology and clinical behavior. A quickly evolving body of data has advanced the understanding of these tumors, leading to effective therapeutics for several histologic subtypes. Biologically rational clinical trials have developed from an understanding of MYB and NOTCH signaling in adenoid cystic carcinoma. The recognition of androgen receptor signaling and HER2-targeted therapy has offered therapeutic options in non-ACC salivary cancers. The use of TRK inhibitors in salivary secretory carcinoma has led to exceptional responses. Immunotherapy is an exciting new therapeutic avenue that requires further exploration.

Prevalence and Clinical Implications of Incidentally Detected Parotid Lesions as Blind Spot on Brain MRI: A Single-Center Experience

Background and objective: This study was conducted to assess the prevalence and clinical implications of parotid lesions detected incidentally during brain magnetic resonance imaging (MRI) examination. Materials and Methods: Between February 2016 and February 2021, we identified 86 lesions in the brain MRI reports of 84 patients that contained the words “parotid gland” or “PG”. Of these, we finally included 49 lesions involving 45 patients following histopathological confirmation. Results: Based on the laboratory, radiological or histopathological findings, the prevalence of incidental parotid lesions was low (1.2%). Among the 45 study patients, 41 (91.1%) had unilateral lesions, and the majority of the lesions were located in the superficial lobe (40/49, 81.6%). The mean size of the parotid lesions was 1.3 cm ± 0.4 cm (range, 0.5 cm–2.8 cm). Of these, 46 parotid lesions (93.9%) were benign, whereas the remaining three lesions were malignant (6.1%). Conclusions: Despite the low prevalence and incidence of malignancy associated with incidental parotid lesions detected on brain MRI, the clinical implications are potentially significant. Therefore, clinical awareness and appropriate imaging work-up of these lesions are important for accurate diagnosis and timely management.

The role of frozen section biopsy for submandibular gland tumors

BACKGROUND

Although there have been several reports of the diagnostic accuracy of frozen section biopsy (FSB) for parotid gland tumors, few studies have focused on its diagnostic accuracy for submandibular gland tumors.

AIM/OBJECTIVES

This study aimed to investigate the necessity of FSB with regard to its diagnostic accuracy for submandibular gland tumors (SGTs).

MATERIALS AND METHODS

About 42 SGT patients underwent both fine-needle aspiration cytology (FNAC) and FSB between 2005 and 2020. The results of FNAC and FSB were analyzed and compared with the final histological diagnoses.

RESULTS

The respective sensitivity and specificity in detecting malignant tumors in 38 cases, excluding the four indeterminate FNAC cases, they were 0 and 97% for FNAC, and 100 and 97% for FSB. Considering the four indeterminate FNAC cases to be malignant, the respective sensitivity and specificity in detecting malignant tumors in the 42 cases were 50 and 92% for FNAC, and 100 and 95% for FSB.

CONCLUSIONS AND SIGNIFICANCE

FSB may be useful for malignancy detection as a final histological diagnosis in cases that are diagnosed as benign or indeterminate by FNAC in SGTs.

Parotid incidentalomas: a systematic review

OBJECTIVE

Parotid incidentalomas on fluorodeoxyglucose positron emission tomography/computed tomography imaging are rare. A systematic review was performed to assess their aetiology and association with scanning indication, and to develop an evidence-based algorithm for their management.

METHODS

A literature search was performed on 25 August 2020 using the keywords 'incidentaloma', 'incidental finding', 'parotid', 'parotid gland', 'salivary gland' and 'head and neck'. Articles were reviewed by two authors before their inclusion.

RESULTS

Forty articles were included, totalling 558 incidentalomas. The mean incidence was 0.74 per cent. Lung cancer was the most common imaging indication. The most common aetiologies were cystadenolymphoma, pleomorphic salivary adenoma and metastases. Only cystadenolymphoma (p = 0.015) and pleomorphic salivary adenoma (p = 0.011) were significantly associated with a primary malignancy (lung). The most common further investigations were aspiration cytology, ultrasound imaging and core biopsy, usually prior to parotidectomy.

CONCLUSION

If appropriate, parotid incidentalomas should be followed up with flexible endoscopy, skin examinations, and head and neck examinations. Ultrasound-guided core biopsy provides higher accuracy, avoiding repeat sampling and excision biopsy.

Surgical interventions for management of benign parotid tumors: A systematic review and network meta-analysis

The impact of the extent of parotid surgery on postoperative complications has long been considered a topic of controversy. The aim of the current network meta-analysis (NMA) is to answer the following questions: (1) Does the extent of surgical resection of benign parotid tumors increase the risk of postoperative complications? (2) What is the best surgical intervention for treatment of benign parotid tumors that can provide an acceptable balance between tumor recurrence rate and other postoperative complications? A comprehensive search on PubMed, Embase, Scopus, and Cochrane library was conducted to identify the eligible studies. The outcome was the incidence of tumor recurrence, facial nerve weakness (temporary [TFW] or permanent [PFP]), Frey's syndrome (FS), sialocele, and salivary fistula. The Bayesian network meta-analysis (NMA) accompanied by a random effect model and 95% credible intervals (CrI) were calculated using the GeMTC R package. Forty-four studies with a total of 7841 participants were included in the current NMA comparing five surgical interventions, namely enucleation, extracapsular dissection (ECD), partial superficial parotidectomy (PSP), superficial parotidectomy (SP), and total parotidectomy (TP). Enucleation showed the highest recurrence rate compared to ECD, SPS, SP, and TP. No statistical differences were observed concerning the recurrence rate when ECD, PSP, SP, and TP were compared together. There was an increased incidence of TFW and FS with the increase in the extent of parotid resection, while no significant difference was found when comparing enucleation with ECD and PSP. SP showed the highest incidence of PFP, and salivary fistula compared to ECD, PSP, and TP. The tumor recurrence rates in enucleation, ECD, PSP, SP, and TP were 14.3%, 3.6%, 3.7%, 2.8%, and 1.4%, respectively. The current NMA demonstrated that the risk of TFW and FS increases with the increase in the extent of parotid resection and that ECD and PSP can be considered the treatment of choice for benign parotid tumors, as both provide an acceptable balance between the incidence of tumor recurrence and facial nerve dysfunction.

Comparative Study of Qualitative and Quantitative Analyses of Contrast-Enhanced Ultrasound and the Diagnostic Value of B-Mode and Color Doppler for Common Benign Tumors in the Parotid Gland

Purpose

To preliminarily identify three common benign parotid gland tumors: pleomorphic adenomas (PA), Warthin tumors (WT), and basal cell adenomas (BCA) by qualitative and quantitative analyses using contrast-enhanced ultrasound (CEUS).

Methods

Preoperative images of parotid gland masses were analyzed, including 129 cases of ultrasonography (US) and color Doppler sonography (CDS) and 110 cases of qualitative and quantitative CEUS. The diagnosis was confirmed by postsurgical pathology outcomes.

Results

PA presented low and heterogeneous enhancement and echo-free area, whereas most WT and BCA presented with high and relatively homogeneous enhancement. Compared with WT and BCA groups, a “slow in” pattern was more common in the PA group and a “slow out” pattern was more frequently noted in the WT group than in the PA and BCA groups. The unique features of qualitative CEUS in the PA group enable distinguishing PA from the 2 other groups. The further distinction among the groups was made based on quantitative parameters of time-intensity curves (TICs), which revealed that the mean peak intensity (PI), mean transit time (MTT), the area under the curve (AUC), and time from peak to one half (HT) exhibited significant differences. ROC analysis was next applied to determine the optimal cutoff points to predict the diagnostic tendency among the groups. When the rising slope (RS) was >2.145, the possibility of BCA was greater than WT.

Conclusions

CEUS ultrasound is of significant value in the differential diagnosis of the 3 common benign parotid gland masses.

2021 Update on Diagnostic Markers and Translocation in Salivary Gland Tumors

Salivary gland tumors are a rare tumor entity within malignant tumors of all tissues. The most common are malignant mucoepidermoid carcinoma, adenoid cystic carcinoma, and acinic cell carcinoma. Pleomorphic adenoma is the most recurrent form of benign salivary gland tumor. Due to their low incidence rates and complex histological patterns, they are difficult to diagnose accurately. Malignant tumors of the salivary glands are challenging in terms of differentiation because of their variability in histochemistry and translocations. Therefore, the primary goal of the study was to review the current literature to identify the recent developments in histochemical diagnostics and translocations for differentiating salivary gland tumors.