P63 expression in papillary cystadenoma and mucoepidermoid carcinoma of minor salivary glands

Intraoral Salivary Gland Cystadenomas: A Case Series Study and Literature Review

BACKGROUND

Salivary gland cystadenoma (SGCA) is a rare benign tumor that predominantly occurs in the parotid gland. SGCAs affecting the minor salivary glands are uncommon and often resemble, clinically and histopathologically, other salivary gland lesions.

METHODS

This study aimed to describe a series of four cases of SGCA affecting intraoral sites and performed a literature review of well-reported SGCA published in the English-language literature.

RESULTS

SGCA cases included in this series were diagnosed in the buccal mucosa, lip, and hard palate of female patients aged between 19 and 78 years. All cases underwent excisional biopsy and were histologically characterized by a multicystic growth with variable degrees of capsule formation and were lined by several types of epithelium, including some cell types that are infrequently reported in SGCA. In some cases, a small collection of lymphocytes was observed adjacent to cystic formations. All SGCA were positive for periodic acid-Schiff, and immunohistochemical reactions were positive for CK7 and p63. The follow-up time ranged widely from 3 to 53 months, and to date, no recurrence has been observed.

CONCLUSION

The literature review revealed a total of 33 published studies accounting for 55 SGCA cases.

Role of p63 in Determining the Histogenesis of Low-Grade Neoplasms versus Cystic Lesion

The biological nature of salivary gland neoplasms and the overlapping characteristics that result from the heterogeneity of the cells of origin make diagnosis difficult. Hence, we intend to present a case of low grade mucoepidermoid carcinoma (MEC) on the palate and to understand the importance of biomarker such as p63 in the early diagnosis of tumor as it also has a role in its histogenesis. A 53-year-old female reported with a unilateral swelling for 3 months on posterolateral palatal region of the right side. Clinical differentials for such palatal swellings include a varied spectrum of lesions such as reactive, benign, and malignant lesions. Based on the incisional and excisional biopsy, histopathological findings and immunohistochemical examination with p63 the case were diagnosed with low grade MEC. The tumor cell differentiation in MEC could be the result of multiplicity of differentiation pathways leading to the formation of various histological patterns. This case report highlights the complexity of salivary gland pathology diagnosis and role of specific tumor marker such as p63 as an early marker for differentiation of salivary gland tumor such as low grade MEC from other cystic lesions occurring on the palate.

Mucoepidermoid carcinoma of the salivary glands revisited with special reference to histologic grading and CRTC1/3-MAML2 genotyping

Mucoepidermoid carcinoma (MEC) is the most common carcinoma of the salivary glands. Here, we have used two large patient cohorts with MECs comprising 551 tumors to study clinical, histological, and molecular predictors of survival. One cohort (n = 167), with known CRCT1/3-MAML2 fusion status, was derived from the Hamburg Reference Centre (HRC; graded with the AFIP and Brandwein systems) and the other (n = 384) was derived from the population-based Cancer Registry of North Rhine-Westphalia (LKR-NRW; graded with the AFIP system). The reliability of both the AFIP and Brandwein grading systems was excellent (n = 155). The weighted kappa for inter-rater agreement was 0.81 (95% CI 0.65-0.97) and 0.83 (95% CI 0.71-0.96) for the AFIP and Brandwein systems, respectively. The 5-year relative survival was 79.7% (95% CI 73.2-86.2%). Although the Brandwein system resulted in a higher rate of G3-MECs, survival in G3-tumors (AFIP or Brandwein grading) was markedly worse than in G1/G2-tumors. Survival in > T2 tumors was markedly worse than in those with lower T-stage. Also, fusion-negative MECs had a worse 5-year progression-free survival. The frequency of fusion-positive MECs in the HRC cohort was 78.4%, of which the majority (86.7%) was G1/G2-tumors. In conclusion, the AFIP and Brandwein systems are useful in estimating prognosis and to guide therapy for G3-MECs. However, their significance regarding young age (≤ 30 years) and location-dependent heterogeneity of in particular G2-tumors is more questionable. We conclude that CRTC1/3-MAML2 testing is a useful adjunct to histologic scoring of MECs and for pinpointing tumors with poor prognosis with higher precision, thus avoiding overtreatment.

Papillary Neoplasms of the Salivary Duct System: A Review

Papillary lesions of the salivary duct systems are uncommon. They encompass a heterogeneous group of benign, intermediate, and potentially aggressive neoplasms. With a few exceptions, historical descriptive terms such as papillary adenocarcinoma, papillary cystadenocarcinoma, and papillary adenoma are being replaced by defined entities, at same time acknowledging the papillary features as a histologic pattern. The evolving genetic landscape of these lesions increasingly permits their reproducible categorization. This article discusses those papillary proliferations encountered in the salivary glands with a focus on intraductal papillary mucinous neoplasms and cystadenomas. Intraductal carcinomas and sialadenoma papilliferum are addressed in separate articles in this issue.

Synchronous Oncocytic Papillary Cystadenoma and Warthin Tumor of the Parotid Gland

Warthin tumor (WT) is the second most common benign salivary gland neoplasm. It is also the most frequent salivary gland tumor to occur synchronously or metachronously with another salivary gland neoplasm, in the same gland or on the other side. Oncocytic papillary cystadenomas (OPCs) are rare neoplasms that are more common in minor salivary gland locations and in women. We describe in detail the case of a 73-year-old male smoker with synchronous OPC and WT of the parotid gland. On microscopy, both tumors resembled each other considerably, with the only difference being that the OPC lacked the tumor-associated lymphoid proliferation characteristic of WT. These findings highlight that OPC bears considerable similarity to WT. While this morphological similarity may lead to misdiagnosis on rare occasions, it does not affect patient management, as clinical behavior of both these tumors is similar.

Immunohistochemical study of salivary gland tumors in a tertiary institution in South-South Region of Nigeria

Aim:

The aim of this study was to see the usefulness of immunohistochemistry in diagnosing salivary gland tumors found in a tertiary health institution.

Materials and Methods:

Twenty-six formalin-fixed paraffin embedded salivary gland tumors were accessioned, and 2 μm were sectioned and processed using Streptavidin-Biotin immunoperoxidase method.

Results:

Adenoid cystic carcinoma (ADCC) was positive to alpha-smooth muscle actin (α-SMA) while mucoepidermoid carcinoma (MEC), polymorphous low-grade adenocarcinoma (PLGA), squamous cell carcinoma (SCC) and oncocytic carcinoma (OCC) were all negative to it. MEC, PLGA, ADCC and the only pleomorphic adenoma (PA) were positive to Ki-67 while both SCC and OCC were negative to it. All the tumors except PA were positive to p63.

Conclusion:

It appears that α-SMA may be used to distinguish ADCC from MEC and PLGA, but Ki-67 cannot be used for this purpose. Furthermore, p63 cannot help in the diagnosis of ADCC, MEC or PLGA. It was concluded that immunochemistry can be used as adjunct to routine H and E stain in the diagnosis of the various salivary gland tumors.

Intraoral Salivary Duct Cyst: Clinical and Histopathologic Features of 177 Cases

The salivary duct cyst (SDC) is a reactive ductal ectasia most frequently seen in major salivary glands, and likely caused by obstruction. The aim of this study is to define the clinical and histopathologic spectrum of intraoral SDCs. Cases were retrieved from the archives of Harvard School of Dental Medicine/StrataDx, Inc. from January 2012 to August 2014. There were 177 cases of which 103 (58.2%) occurred in females, with a median age of 56 (range 2-95). Approximately half of cases (45.8%) presented in the area of the buccal mucosa, lower lip mucosa, or mandibular vestibule, and 23.2% presented in the floor of mouth. SDCs were lined at least focally by 1-2 layers of cuboidal/columnar epithelium in 85.3% of cases and showed varying degrees of metaplasia (oncocytic, mucous cell, squamous, ciliated, apocrine-like) in 68.4% of cases. Intraluminal mucous stasis was present in 41.8% of SDCs, incipient calcification was present within 4.5% of SDCs, and chronic obstructive sialadenitis was seen in 90.2% of cases. No cysts showed adenomatous ductal proliferations or true papillary structures with fibrovascular cores, although 41.2% exhibited reactive undulation of cyst lining. Thirty-nine 'papillary oncocytic cystadenoma-like' SDCs (22.0%) demonstrated complete oncocytic metaplasia and marked undulation. An additional seven such cysts (4.0%) had a 'Warthin tumor-like' lymphoplasmacytic infiltrate. Intraoral SDCs occur most commonly in the sixth decade of life in locations distinct from extravasation mucoceles, likely secondary to intraluminal obstruction. SDCs show diverse histopathology and certain phenotypic variants may be mistaken for papillary oncocytic cystadenoma or Warthin tumor.

Expression of Membrane-Bound Mucins and p63 in Distinguishing Mucoepidermoid Carcinoma from Papillary Cystadenoma

The aim of this study was to compare the immunoexpression of epithelial mucins (MUCs) in salivary duct cysts, papillary cystadenomas, and mucoepidermoid carcinomas and to evaluate if any of these markers could be useful for differentiating between mucoepidermoid carcinoma and papillary cystadenoma. We also sought to validate the p63 expression pattern found to differentiate between mucoepidermoid carcinoma and papillary cystadenoma. Immunoexpression of MUC1, MUC2, MUC4, MUC7, and p63 was studied and quantified in 22 mucoepidermoid carcinomas, 12 papillary cystadenomas, and 3 salivary duct cysts. The immunohistochemical evaluation was collectively performed by 3 oral pathologists. Scores and trends in proportions were assessed using the nonparametric Wilcoxon-Mann-Whitney rank sum test. Mucoepidermoid carcinomas, papillary cystadenomas, and salivary duct cysts demonstrated variable MUC expression patterns. All tumors were positive for p63 immunoexpression with p63 labeling in salivary duct cysts and papillary cystadenomas (15/15) limited to the basal layers of the cystic spaces, whereas in mucoepidermoid carcinomas (22/22) the p63 labeling extended throughout the suprabasal layers (p < 0.001). This study adds more confirmatory data to validate that the reactivity pattern of p63 protein can be used in distinguishing between papillary cystadenoma and low-grade mucoepidermoid carcinoma. Although positive reactivity in a tumor with MUC1 and MUC4 was inconclusive, negative reactivity suggests the diagnosis of a benign PC or SDC.

Review and Updates of Immunohistochemistry in Selected Salivary Gland and Head and Neck Tumors

Context

Immunohistochemistry is a useful tool for diagnosing salivary gland and head and neck tumors.

Objective

To review immunohistochemical markers, which can aid in the diagnosis of selected salivary gland and head and neck tumors.

Data Sources

Literature review and authors' personal practice experience.

Conclusions

Salivary gland and head and neck tumors include a large diverse group of tumors with complex and overlapping histologic features. Immunohistochemistry plays an important role in resolving the differential diagnosis of some salivary gland and head and neck tumors and can provide information for the prognosis of certain tumors.

Increased expression of MUC-1 has close relation with patient survivor in high-grade salivary gland mucoepidermoid carcinoma

PURPOSE

High-grade mucoepidermoid carcinoma (MEC) is an infrequent malignant neoplasm originates most commonly in the salivary glands with poor prognosis. Thus far, there is little knowledge on MUC-1 expression in high-grade MEC or how it may relate to patient survival. The aim of this study was to determine the extent of MUC-1 expression in high-grade MEC and correlate expression with clinic outcome.

METHODS

Surgical specimens from 62 cases of primary high-grade MEC and 10 cases of normal salivary gland tissue were examined by immunohistochemistry. The relationship between MUC-1 expression and the clinicopathological data and patient survival was analyzed.

RESULTS

The disease-free survival rates were 54.6% (3 years) and 37.7% (5 years) for high-grade MEC patients. Patient who with primary location at submandibular gland have the worst prognosis (P = 0.042) in comparing with other sites. High expression of MUC-1 in high-grade MEC was significantly correlated with lymphatic/regional metastasis (P = 0.003) and clinic stage (P = 0.02), and high expression of MUC-1 (>75%) was confirmed to be significant independent prognostic factors in high-grade MEC patients [HR 2.929 (95% CI 1.246-6.881); P < 0.0137].

CONCLUSIONS

The findings suggest that high levels of MUC-1 expression may be a potential marker for worse outcome in high-grade MEC and could be used as a new molecule target to improve outcomes for these patients in the future.