Epithelial-Myoepithelial Carcinoma

Unusual pulmonary nodules diffusion from epithelial‑myoepithelial carcinoma on 18F‑FDG PET/CT: A case report

Epithelial-myoepithelial carcinoma (EMC) is a rare low-grade malignant tumor with uncommon regional lymph node metastasis and distant metastasis. The diagnosis of this disease primarily relies on the examination of pathological morphology and immunohistochemical staining, as its clinical symptoms and imaging findings are non-specific. This makes it more difficult to provide specific information about EMC lung metastasis. The present report describes a biopsy-confirmed case of pulmonary metastases arising from EMC of the parotid. The pulmonary nodules were dispersed throughout both lungs and exhibited varying degrees of fluorodeoxyglucose (FDG) uptake on positron emission tomography-computed tomography scans. Additionally, the pathological and immunohistological presentation of the lung mass was similar to that of the primary lesion. Several pulmonary nodules exhibiting varying degrees of FDG uptake may be considered a distinctive sign of metastasis on EMC imaging. Reviewing the present case, along with other similar rare cases in the literature, is crucial to accurately evaluate the imaging examinations of such patients to identify and establish an appropriate treatment plan for potential metastatic lung cancer. It also highlights the importance of not underestimating the malignant potential of EMC and the necessity for close follow-up.

Reappraisal of Oncocytic Adenocarcinoma: Unveiling Its Connection to Oncocytic Variants of Salivary Duct Carcinoma and Mucoepidermoid Carcinoma Through ImmunoHisto-Molecular Perspectives

Oncocytic adenocarcinoma (OC) of the salivary glands is a rare and controversial entity. It was recently reclassified as "salivary carcinoma NOS and emerging entities" in the 2022 WHO classification of head and neck tumors. The lack of specific molecular alterations and its potential affiliation with other salivary gland carcinomas, such as the oncocytic mucoepidermoid carcinomas (OMEC) or the oncocytic subtype of salivary duct carcinomas (OSDC) justified this reclassification. It is becoming essential to clarify the complex spectrum of potential diagnoses surrounding oncocytic tumors. The objective of this study was to explore the histologic features, as well as the immunohistochemical and molecular profiles, of cases previously diagnosed as OC or OMEC of the salivary glands. This study involved 28 cases of carcinomas with a predominantly oncocytic component. The sex distribution was equal. The median age was 59 years (range 10 to 89). Most of these cases originated from the parotid gland (25/28). The mean tumor size was 2.4 cm (range 0.5 to 6.5). Primary immuno-morphological and mutation/gene fusion profiles reclassified mainly (64.3%, 18/28). Most of them were reclassified in descending order as OSDC (8/18), OMEC (5/18), and OC (2/18). But 3 cases remained unclassified (3/18). The transcriptomic analysis found a proximity of their transcriptomic profile with the OMEC group and a distance from the OSDCs. These findings imply that OC is not distinct but represents oncocytic variants of other salivary carcinomas. It underscores the importance of thorough morphologic, immunohistochemical, and molecular examinations to accurately diagnose carcinomas with predominant oncocytic components in the salivary glands.

Epithelial-Myoepithelial Carcinoma: Insights From a Case Report

Epithelial-myoepithelial carcinoma (EMC) is an uncommon malignancy that usually originates in the salivary glands. Its occurrence in the maxillary sinus is rare. We present a case of a 68-year-old male patient who has been experiencing swelling in the upper right back region of the jaw for the past three months. A computerized tomography scan of the paranasal sinus suggested the possibility of a malignant neoplastic mass originating from the right maxillary sinus, with significant local extension and bony erosions. Histopathology examination of EMC revealed a tubular morphology lined with inner luminal cells and outer clear cells of myoepithelial origin. For confirmatory diagnosis, immunohistochemistry (IHC) markers were applied, in which the inner lining of cells was positive for S100, while the outer lining of cells tested positive for both p63 and S100. The patient underwent a hemi-maxillectomy of the right side under general anesthesia.

Epithelial-Myoepithelial Carcinoma of the Parotid Gland: A Report of a Rare Case and Review of Literature

Epithelial-myoepithelial carcinoma (EMC) is a rare tumor, characterized by two different cell populations and both demonstrate a malignant nature microscopically. It constitutes less than 2% of all salivary gland malignancies. The World Health Organization (WHO) has classified this disease as a separate pathological category. The diagnosis of this tumor is arrived by biopsy. It shows slow growth and is small in size; it appears in ulcerative form of mucosa in some cases. Gland cells consist of two layers of outer myoepithelium cells and inner epithelial cells. Vimentin staining is positive. It shows calponin, muscle-specific actin, S100, smooth muscle actin, p63, and smooth muscle myosin heavy chain I. Examining different sets of data reveals that tumors exhibiting a solid growth pattern, nuclear atypia, DNA aneuploidy, and increased proliferative activity typically display a more aggressive nature, accompanied by a heightened likelihood of local recurrences and metastases. The clinical and radiological observations frequently resemble those of a benign tumor. Due to the uncommon nature of EMC, there is currently no established standard treatment protocol. It is considered a low-grade tumor where good resection holds better results. Individuals displaying histopathological indicators of aggressive disease should be evaluated for potential adjuvant radiotherapy. We present a case of a patient who had recurrence twice in a period of seven years despite surgical management, chemotherapy, and radiotherapy.

Clinicopathological features and prognostic factors of salivary gland myoepithelial carcinoma: institutional experience of 42 cases

Myoepithelial carcinoma (MECA) is a rare type of carcinoma for which the clinicopathological features and prognostic factors have not yet been fully clarified. A retrospective study of 42 patients diagnosed with salivary gland MECA was performed, focusing on the clinicopathological features and prognostic factors. Of the 42 patients, 20 died of cancer, 20 lived without tumour, one lived with distant metastasis, and one was lost to follow-up. Overall, 69.0% had tumour recurrence, 16.7% had cervical nodal metastasis, and 21.4% had distant metastasis. The 5-year overall survival rate was 70.2%. Kaplan-Meier analysis revealed that patients with pathological positive lymph nodes (pN+), multiple recurrences of tumour, and higher histological grade had worse overall survival. Multivariate Cox analysis indicated pN+ and higher histological grade to be independent predictors of decreased survival. The 5-year overall survival rate in the pN0 group was 87.5%, while that in the pN+ group was 28.6%. In conclusion, myoepithelial carcinoma can be defined as a tumour with a high incidence of recurrence and poor prognosis, especially in pN+ patients. Pathological positive lymph nodes and histological grade may serve as predictors of survival.

Molecular pathology in diagnosis and prognostication of head and neck tumors

Classification of head and neck tumors has evolved in recent decades including a widespread application of molecular testing in tumors of the salivary glands, sinonasal tract, oropharynx, nasopharynx, and soft tissue. Availability of new molecular techniques allowed for the definition of multiple novel tumor types unique to head and neck sites. Moreover, the expanding spectrum of immunohistochemical markers facilitates a rapid identification of diagnostic molecular abnormalities. As such, it is currently possible for head and neck pathologists to benefit from a molecularly defined classifications, while making diagnoses that are still based largely on histopathology and immunohistochemistry. This review highlights some principal molecular alterations in head and neck neoplasms presently available to assist pathologists in the practice of diagnosis, prognostication and prediction of response to treatment.

Algorithm for the reconstruction of the parotid region: a single institution experience

OBJECTIVE

This study aims to discuss the characteristics and treatment methods of malignant tumors in the parotid region, as well as the therapeutic effects of immediate free flap reconstruction of soft tissue for postoperative defects.

MATERIALS AND METHODS

A retrospective review was conducted on 11 cases of soft tissue flap reconstruction for postoperative defects following the resection of malignant tumors in the parotid region. Statistical analysis was performed based on clinical data.

RESULTS

Among the 11 cases of malignant tumors in the parotid region, there were 2 cases of secretory carcinoma (SC) of the salivary gland, 2 cases of squamous cell carcinoma (SCC), 2 cases of carcinosarcoma, 1 case of mucoepidermoid carcinoma (MEC), 1 case of epithelial-myoepithelial carcinoma (EMC), 1 case of salivary duct carcinoma (SDC), 1 case of basal cell carcinoma (BCC), and 1 case of osteosarcoma. Among these cases, 4 were initial diagnoses and 7 were recurrent tumors. The defect repairs involved: 8 cases with anterolateral thigh free flap (ALTF), 2 cases with pectoralis major muscle flaps, and 1 case with forearm flap. The size of the flaps ranged from approximately 1 cm × 3 cm to 7 cm × 15 cm. The recipient vessels included: 4 cases with the facial artery, 4 cases with the superior thyroid artery, and 1 case with the external carotid artery. The ratio of recipient vein anastomosis was: 57% for branches of the internal jugular vein, 29% for the facial vein, and 14% for the external jugular vein. Among the 8 cases that underwent neck lymph node dissection, one case showed lymph node metastasis on pathological examination. In the initial diagnosis cases, 2 cases received postoperative radiotherapy, and 1 case received 125I seed implantation therapeutic treatment after experiencing two recurrences. Postoperative follow-up revealed that 2 cases underwent reoperation due to local tumor recurrence, and there were 2 cases lost to follow-up. The survival outcomes after treatment included: one case of distant metastasis and one case of death from non-cancerous diseases.

CONCLUSION

Immediate soft tissue flap reconstruction is an important and valuable option to address postoperative defects in patients afflicted with malignant tumors in the parotid region.

Epithelial-Myoepithelial Carcinoma of Nasal Cavity at an Unusual Age: A Case Report and Review of Literature

Introduction

Epithelial-myoepithelial carcinoma (EMC) was recognised as a distinct pathologic entity in World Health Organisation classification. It is an extremely rare low grade carcinoma of salivary gland, with characteristic biphasic tubular structures. It predominantly occurs in Parotid gland but can also be seen in nasopharynx, lacrimal gland, paranasal sinuses, larynx, lung. Nasal EMC (excluding the paranasal sinuses as primary tumour site) are very rare with only 13 cases reported till date. In this case report, we described a case of nasal EMC extending into nasopharynx, its clinical features and management. We have also done a literature review of all the relevant cases of nasal EMC.

Material and Methods

We searched the PubMed database for articles between January 1950 and December 2022 for nasal EMC for this review.

Results

We found 13 relevant case reports of nasal EMC and median age was 58 years with female preponderance. We found that our patient was the youngest to be reported till date. Two cases, including the current study, showed epicentre of the tumour in posterior nasal cavity, extending to choana and nasopharynx. Most common presentation was epistaxis, followed by nasal obstruction. Only 4 out of 14 cases had information on surgical margin status, out of which only one has positive surgical margin. Five patients (including the patient in the current study) received adjuvant radiotherapy; however 6 patients (42.8%) did not receive any adjuvant radiotherapy.

Epithelial-myoepithelial carcinoma with multiple recurrences: An unusual presentation

Epithelial-myoepithelial carcinoma (EMC) is a type of malignant salivary gland tumors that is extremely rare. EMC primarily affects major salivary glands, particularly the parotid gland, but minorsalivary glands are also affected. It contributes less than 0.5-1% of all salivary gland neoplasms. Multiple recurrences are relatively rare with EMC. There have been very few reports of multiplerecurrences in the literature. Biphasic tubular structures composed of externalclear cells and inner ductal cells are the distinguishing histopathological feature. However, histological variation is prevalent, making a precise diagnosis challenging. We present a case of EMC that had multiple recurrences during a six-year period.

Salivary Gland-like Tumors of the Breast

CONTEXT

The World Health Organization classification of tumors of the breast recognizes several special type carcinomas and benign lesions with features comparable to those of salivary gland tumors.

OBJECTIVE

To discuss the histologic, immunophenotypic, molecular, and clinical features of salivary gland-like carcinomas of the breast. These breast tumors are often negative for hormone receptors and human epidermal growth factor receptor 2 (HER2), that is, triple-negative, but they generally have a much better prognosis than triple-negative breast carcinomas of no special type. We compare the immunophenotypic, molecular, and clinical features of these breast tumors with their salivary gland counterparts, highlighting similarities and differences. We also discuss benign salivary gland-like breast tumors. Finally, we highlight recent developments in understanding the molecular pathogenesis of these breast tumors and novel ancillary studies that can be used to support their diagnosis.

DATA SOURCES

A literature review was conducted, and papers were selected for further analysis and discussion by the authors of this review based on their novelty, applicability, and impact in the field.

CONCLUSIONS

Breast tumors that exhibit morphologic overlap with salivary gland tumors have been recognized by pathologists for decades, but the similarities and differences in their molecular pathogenesis have not been understood until more recently. These developments have led to novel diagnostic tools and further knowledge of these rare breast lesions.

Repeated Surgery in a Case of Epithelial-Myoepithelial Carcinoma of the Parotid Gland that was Difficult to Distinguish from Pleomorphic Adenoma

Epithelial-myoepithelial carcinoma (EMC) of the parotid gland is a comparatively rare tumor that accounts for less than 1% of all salivary gland tumors. A patient with EMC of the parotid gland that was initially diagnosed as pleomorphic adenoma and that recurred locally during the watchful waiting period but was controlled by surgery under local anesthesia is reported. An 80-year-old man had noticed a swelling in the left infra aural region. A left parotid gland tumor was suspected, and he was referred to our department. Magnetic resonance imaging (MRI) and fine-needle aspiration cytology findings were suggestive of pleomorphic adenoma of the superficial lobe of the parotid gland, and this was therefore resected under general anesthesia. Postoperative histopathological examination, immunostaining, and genetic tests resulted in a diagnosis of EMC. Postoperative pathological review showed that part of the resection margin was positive. The possibility of recurrence was explained to the patient, and additional treatment was recommended, but since the patient did not desire this, a policy of watchful waiting was adopted. Signs of cutaneous metastasis in the left infra aural region were detected at 13 months postoperatively, and this metastasis was excised under local anesthesia. The resection margin was negative, and the patient's course remains uneventful. EMC is classified as a low-grade malignant tumor, but it requires stringent monitoring because of its frequent local recurrence. Since local control can usually be achieved by surgical treatment alone, and postoperative adjuvant therapy may not necessarily warranted.

Top Ten Differentials to Mull Over for Head and Neck Myoepithelial Neoplasms

BACKGROUND

Myoepithelial neoplasms of the salivary gland are benign or malignant neoplasms composed exclusively of neoplastic myoepithelial cells. These tumors, including the benign myoepithelioma and the malignant counterpart myoepithelial carcinoma, exhibit a wide range of cytomorphologic features and architectural patterns.

METHODS

Review.

RESULTS

Myoepithelial cells can be epithelial, plasmacytoid, clear cell, spindle cell, and/or oncocytic cell, arranging as trabeculae, solid sheets, nests, cords, and/or single cells. A stromal component is commonly but not universally present, Therefore, their differential diagnoses are quite broad, including salivary gland neoplasms especially those with a myoepithelial component, plasmacytoma, melanoma, and various mesenchymal tumors.

CONCLUSION

In this review, we summarize the characteristic histologic features, useful immunohistochemical panel, and common molecular alterations of myoepithelial tumors and their top differential diagnoses. A logical stepwise algorithmic approach and an immunohistochemical panel to include multiple myoepithelial markers are essential to establish the correct diagnosis.

Top 10 Clear Cell Head and Neck Lesions to Contemplate

BACKGROUND

Optically clear cytoplasm may occur in neoplastic and non-neoplastic conditions, either as a characteristic feature of a disease entity or as a morphologic rarity, potentially creating diagnostic dilemmas in various organ systems. In the head and neck, clear cell change can occur in lesions of salivary, odontogenic, thyroid, parathyroid, or sinonasal/skull base origin, as well as in metastases to these regions.

METHODS

This review elaborates the top ten clear cell lesions in the head and neck, emphasizing their distinguishing histologic, immunohistochemical, and molecular attributes, and presents a rational approach to arriving at an accurate classification.

RESULTS

Cytoplasmic pallor or clearing may be caused by accumulations of glycogen, lipid, mucin, mucopolysaccharides, water, foreign material, hydropic organelles, or immature zymogen granules. Overlapping morphologic features may present a diagnostic challenge to the surgical pathologist. Similarity in immunohistochemical profiles, often due to common cell type, as well as rare non-neoplastic mimics, furthers the diagnostic conundrum.

CONCLUSIONS

The top ten lesions reviewed in this article are as follows: (1) clear cell carcinoma (salivary and odontogenic), (2) mucoepidermoid carcinoma, (3) myoepithelial and epithelial-myoepithelial carcinoma, (4) oncocytic salivary gland lesions, (5) squamous cell carcinoma, (6) parathyroid water clear cell adenoma, (7) metastatic renal cell carcinoma (especially in comparison to clear cell thyroid neoplasms), (8) sinonasal renal cell-like adenocarcinoma, (9) chordoma, and (10) rhinoscleroma.

Differences between complex epithelial neoplasms of the ovary and high-grade serous ovarian cancer: a retrospective observational cohort study

BACKGROUND

Complex epithelial neoplasms of the ovary (CENO), an uncommon pathological histotype in ovarian cancer, comprises adenosquamous carcinoma and adenocarcinoma with metaplasia. Owing to the rarity of relevant reports, there are currently no statistics on outcomes based on large samples. Meanwhile high-grade serous ovarian cancer (HGSOC) is the most common histotype in ovarian cancer which has a recognized first-line treatment regimen and poor prognosis. Thus, we aimed to determine the characteristics, prognosis, and independent predictors of survival for CENO, compare them with those of HGSOC and construct prognostic predictive models and nomograms.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database to determine patients diagnosed with CENO or HGSOC from 2000 to 2017. Clinical, demographic, and treatment characteristics were compared between these groups. Propensity score matching, Cox risk regression analysis, Kaplan-Meier survival curves, and the Least Absolute Shrinkage and Selection Operator regression analysis were employed for analyzing the data.

RESULTS

Here, 31,567 patients with HGSOC and 216 patients with CENO between 2000 and 2017 in the SEER database were enrolled. Age < 57 years, unmarried, and early-stage diseases were more common in patients with CENO than in those with HGSOC. Women with CENO were less likely to receive adjuvant chemotherapy (65.7% vs. 79.4%) but more likely to receive radiotherapy (6.0% vs. 0.8%; both p < 0.001) than those with HGSOC. Year of diagnosis, surgery status, number of primary tumors, grade, and FIGO stage were independent prognostic factors for overall and cancer-specific survival in CENO. Overall survival rates were significantly lower for CENO than for more malignant HGSOC.

CONCLUSIONS

In summary, CENO was rare in ovarian cancer, while the year of diagnosis, surgery status, number of primary tumors, grade, and FIGO stage were independent prognostic factors. Compared with other common malignant ovarian tumors, CENO had a poor prognosis. Prognostic predictive models and nomograms had been determined to predict the individual survival rates of patients with CENO. These methods could improve evaluations of survival and therapeutic decisions for patients.

Clear Cell Neoplasms of Salivary Glands: A Diagnostic Challenge

This review focuses on the heterogenous group of clear cell neoplasms of salivary glands and attempts to identify major differential diagnostic features. Within the head and neck region, clear cells are found most commonly in salivary gland tumors, but may also be seen in tumors of squamous or odontogenic epithelial origin, primary or metastatic carcinomas, benign or malignant melanocytic lesions, or benign or malignant mesenchymal tumors. Clear cells occur fairly commonly among a wide variety of salivary gland neoplasms, but mostly they constitute only a minor component of the tumor cell population. Clear cells represent a major diagnostic feature in two salivary gland neoplasms, epithelial-myoepithelial carcinoma and hyalinizing clear cell carcinoma. In addition, salivary gland neoplasms composed predominantly of clear cells could also include clear cell variants of other salivary neoplasms, such as mucoepidermoid carcinoma and myoepithelial carcinoma, but their tumor type-specific histologic features may only be available in limited nonclear cell areas of the tumor. Diagnosing predominantly clear cell salivary gland tumors is difficult because the immunoprofiles and morphologic features may overlap and the same tumor entity may also have a wide range of other histologic presentations. Many salivary gland tumors are characterized by tumor type-specific genomic alterations, particularly gene fusions of the ETV6 gene in secretory carcinoma, the MYB and MYBL1 genes in adenoid cystic carcinoma, the MAML2 gene in mucoepidermoid carcinoma, the EWSR1 gene in hyalinizing clear cell carcinoma, and others. Thus, along with conventional histopathologic examination and immunoprofiling, molecular and genetic tests may be important in the diagnosis of salivary gland clear cell tumors by demonstrating genetic alterations specific to them.