Clinicopathological analysis of salivary gland carcinomas and literature review

Primary and Secondary Tumors of the Parotid Gland: Clinical Features and Prognosis

Primary and secondary malignant tumors can affect the parotid gland. The aim of this retrospective study was to evaluate the clinical features and prognosis of malignant epithelial tumors of the parotid gland. In particular, a comparison between primary and secondary cancer and survival analyses were performed. Eighteen patients with primary cancer and fifteen with intraparotid metastasis from cutaneous squamous cell carcinoma were included. A chart review was performed to collect clinical data (age, sex, smoking, alcohol consumption, tumor stage, type of surgical procedure, complications, recurrence and death). The majority of primary tumors were early (T1-2 N0, 83%) with mucoepidermoid carcinoma being the most common (33%). Secondary tumors were mostly staged P2 (53%) and N0 (67%). Subjects with secondary tumors were older than those with primary cancer. Post-operative permanent facial palsy was observed in 5 patients (17%) with primary cancer and 9 (60%) with secondary tumors (p = 0.010). Two-year overall survival for primary and secondary parotid cancer was 76.58% and 43.51%, respectively (p = 0.048), while 2-year disease-free survival was 76.05% and 38.50%, respectively (p = 0.152). In conclusion, secondary cancer of the parotid gland has worse survival than primary tumors. In the future, the implementation of multimodality treatment of intraparotid metastases is necessary to improve oncologic outcomes.

[Acinic cell carcinoma: an unsuspected malignancy of the nasal cavity]

Acinic cell carcinoma (ACC) is a low grade malignant tumor of the salivary glands. Primary ACC affects most frequently the parotid gland and can rarely arise in the minor salivary glands of the oral cavity, pharynx and larynx. It is extremely rare in the nasal cavity; to our knowledge only 18 cases of primary ACC of the nasal cavity are reported in the English-written literature. Herein we report a case of acinic cell carcinoma of the nasal cavity, describe the clinical, radiological and microscopic features of this uncommon presentation and finally provide a discussion in the light of relevant literature.

Oncological outcomes of parotid gland malignancies: a retrospective analysis of 74 patients

INTRODUCTION

Salivary gland malignancies are rare neoplasms whose management has been evolving over the last two decades. Nevertheless, patient outcomes have not improved accordingly.

OBJECTIVE

In the present paper, factors and variables that could influence Overall, Disease-Specific and Disease-Free Survival, and Loco-Regional Control were analyzed.

METHODS

Chart data from 74 patients who underwent parotid gland surgery were retrospectively analyzed and stratified for tumor histology, grading, size, pT stage, pN stage, extracapsular spread, involved salivary gland lobe, and age at diagnosis. Major outcomes were estimated at 5 years by Kaplan-Meier curves.

RESULTS

Advanced stage, high grade, and lymph nodes involvement greatly impaired patient outcomes. Furthermore, in our cohort, the age at diagnosis ≥ 55 was a cause of poorer disease survival likely due to a different distribution in tumor histotypes between older and younger patients. Despite the two groups were homogeneous for the numerosity of squamous cell carcinomas, older patients were more rarely affected by mucoepidermoid and acinic cell carcinomas, which have generally better prognosis. Finally, patients aged ≥ 55 had a more frequent pathological involvement of the deep lobe of the parotid gland if compared to the younger counterpart.

CONCLUSION

The rarity of some salivary gland tumor histotypes requires further high-number series to fully understand the prognostic factors for both patient survival and recurrence development. In our cohort, the age at diagnosis ≥ 55 raises concerns that play crucial roles in disease survival shortening.

Immunohistochemical investigations on the expression of programmed cell death ligand 1, human leukocyte antigens G and E, and granzyme B in intraoral mucoepidermoid carcinoma

OBJECTIVE

To identify the expression of nonclassical human leukocyte antigen G and E (HLA-G and -E), programmed cell death ligand-1 (PD-L1) and granzyme B (GB) in intraoral mucoepidermoid carcinomas (MECs), and to assess whether such expressions are related to metastasis, survival, staging, tumor grade and number of GB-positive cells.

DESIGN

For this cross-sectional study, samples of MEC (n=30) were selected and classified as low-grade (LG), intermediate-grade (IG) or high-grade (HG), according to the WHO grading system. HLA-G, -E and PD-L1 were identified by immunohistochemistry and quantified as the proportion of positive neoplastic cells. The density of GB+ cells was also evaluated. The Kruskal-Wallis test was used with a 5% significance level.

RESULTS

Expressions of HLA-G, -E and PD-L1 were identified in the majority of epidermoid, intermediate and clear cells, but not in the mucous cells of the MECs. The quantitative analysis of the total percentage of positive neoplastic cells showed overexpression of this set of proteins in all MEC samples. The expression of these proteins and histological grading were positively correlated [HLA-G (LG=79% positive cells, IG=96%, HG=99%; p=0.0004), HLA-E (LG=70%, IG=96%, HG=99%; p<0.0001) and PD-L1 (LG=34%, IG=79%, HG=80%; p=0.01)]. No relationship was observed between the immunosuppressive proteins and other clinicopathological parameters. Low GB density was found in all MEC samples.

CONCLUSIONS

The augmented expression of HLA-G, -E and PD-L1 in the intraoral MEC might suggest a role of these molecules in the scape of neoplastic cells from immunosurveillance.

Characteristics of salivary gland tumours in the United Arab Emirates

Salivary gland tumours (SGT) are relatively rare cancers characterised by striking morphological diversity and wide variation in the global distribution of SGT incidence. Given the proximity to the head and neck structures, management of SGT has been clinically difficult. To the best of our knowledge, there are no epidemiological studies on SGT from the United Arab Emirates (UAE) or the Gulf Cooperation Council Countries (GCC). Patient charts (N = 314) and associated pathological records were systematically reviewed between the years 1998–2014. Predominance of benign (74%) compared with malignant (26%) SGT was observed. Among the 83 malignant SGT identified, frequency was higher in males (61%) than in females (39%) and peak occurrence was in the fifth decade of life. Mucoepidermoid carcinoma was the most common type of tumour (35%) followed by adenoid cystic carcinoma (18.1%) and acinar cell carcinoma (10.8%). A similar pattern of tumour distribution was seen in patients from GCC, Asian, and Middle East countries. This is the first report to address the distribution of salivary gland tumours in a multiethnic, multicultural population of the Gulf. The results suggest that the development of an SGT registry will help clinicians and researchers to better understand, manage, and treat this rare disease.

Is DOG1 really useful in the diagnosis of salivary gland acinic cell carcinoma? - A DOG1 (clone K9) analysis in fine needle aspiration cell blocks and the review of the literature

INTRODUCTION

DOG1 is a transmembrane protein originally "discovered on gastrointestinal stromal tumors," works as a calcium-activated chloride channel protein. There is a limited number of studies on the potential usage of this antibody in the diagnosis of salivary gland tumors on routine practice in cell blocks. The aim of this study was to search for the usefulness of K9 clone in oncocytic type tumors and review of the literature.

MATERIALS AND METHODS

Sixty-nine fine needle aspiration (FNA) cytologic materials of predominantly oncocytic morphology salivary gland tumors; acinic cell carcinoma (AciCC) (n = 8), adenoid cystic carcinoma (n = 2), pleomorphic adenoma (PA) (n = 22), Warthin tumor (WT) (n = 20), myoepithelioma (ME) (n = 5), benign oncocytoma (BeO) (n = 3), mucoepidermoid carcinoma (MEC) (n = 7), mammary analog salivary gland carcinoma (n = 2) were immunostained with DOG1 (clone K9) stain.

RESULTS

Of the 8 AciCCs, 7 were observed apical-luminal positive staining, demonstrating 1-3 + intensity, and involving 40-70% of the tumor cells. One MEC of 7 (14%), 1 ME of 5 (20%), and 4 PA of 22 (18%) showed weak (1+) cytoplasmic granular staining in 5-10% of the tumor cells. Pure oncocytic neoplasms (WT, BeO) showed no expression with DOG1-K9.

CONCLUSIONS

FNA is a common tool in the diagnosis and management of salivary gland tumors. DOG1-K9 clone was very useful with a unique staining pattern of apical-luminal positivity in the differential diagnosis of AciCC from other oncocytic salivary gland tumors.