Epithelial-myoepithelial carcinoma of the salivary gland--a low grade malignant neoplasm? Report of two cases and review of the literature

Long-Term Disease Control of Locally Invasive Epithelial-Myoepithelial Carcinoma of Parapharyngeal Salivary Glands With Definitive Radiotherapy

Epithelial-myoepithelial carcinoma (EMC) is a rare clinical entity that affects glandular tissues, most commonly salivary glands. EMC of parapharyngeal space is exceedingly rare. Surgery is the mainstay of treatment with or without chemotherapy, radiotherapy, or both. Due to the rarity of the disease, select cases where surgery is not possible present a management conundrum. We present a case of locally advanced, stage IVa EMC of parapharyngeal space that was treated with upfront definitive radiotherapy. Radiotherapy treatment alone led to long-term disease control in both clinical and radiological follow-ups. The patient was followed for more than eight years posttreatment with no disease recurrence, enjoying the normal activities of life with no late toxicities including xerostomia. This case report highlights the role of radiotherapy in the management of such patients, and more studies are required in this context for surgical candidates with positive disease margins.

[Rare association of a pleomorphic adenoma and epithelial myoepithelial carcinoma of the parotid gland]

Le Carcinome épithélial - myoépithélial (CEM) est une tumeur maligne rare des glandes salivaires touchant principalement la glande parotide. Son association avec un adénome pléomorphe est exceptionnelle. Nous rapportons le cas d'une femme de 57 ans avec adénome pléomorphe de la glande parotide évoluant depuis plusieurs années. L'augmentation récente du volume de la glande associée à l'apparition d'adénopathies cervicales homolatérales nous a fait penser à une transformation maligne. L'examen histologique final après parotidectomie totale a montré une association inattendue d'un adénome pléomorphe et un CEM. Le CEM est une tumeur maligne de bas grade. Elle peut survenir de novo ou sur un adénome pléomorphe. La transformation maligne de l'adénome est suspectée devant l'augmentation rapide du volume de l'adénome avec apparition d'adénopathies cervicales. Toutefois, ces modifications cliniques peuvent annoncer l'apparition d'une tumeur distincte. Malgré sa tendance à la récidive locale et un faible potentiel métastatique, de rares cas de CEM peuvent avoir un comportement agressif et des métastases à distance. Le traitement consiste principalement en une résection chirurgicale complète si possible suivie d'une radiothérapie dans le but de prévenir la récidive locale.

Epithelial-myoepithelial carcinoma of external auditory canal evolving from pleomorphic adenoma

A 45-year-old female patient visited the clinic due to ear fullness. A 8 mm sized mass was found in the external auditory canal. It was surgically removed and the pathology exam confirmed epithelial-myoepithelial carcinoma (EMC). EMC is glandular epithelial neoplasm of the salivary gland. EMC originating from the external auditory canal is very rare, and only 1 case has been reported so far in the literature. The difference between our case and the one previously published was that the tumor was previously proven as a benign tumor (i.e. pleomorphic adenoma) 5 years ago. Therefore, this is the first case in the literature showing the evolvement of pleomorphic adenoma of the external auditory canal into EMC.

Parotid carcinoma: Current diagnostic workup and treatment

In this review we present recent progress in diagnostic workup, prognostic evaluation, treatment options and resulting outcomes. Whenever possible, complete resection remains the mainstay of treatment. Sacrifice of facial nerve branches is reserved for the clinically or electromyographically dysfunctioning facial nerve. Clinical or radiological neck disease demands combined surgery and radiotherapy. Treatment of the N0 neck is indicated for advanced stage-high grade tumors but the question remains unanswered whether this should be surgical or radiotherapeutic elective treatment. Surgery alone will cure low stage, low grade tumors, that show no additional negative prognostic factors following adequate resection. In all other tumors postoperative radiotherapy will improve locoregional control. This approach results in good locoregional control, in a way that distant metastasis remains the typical presentation of treatment failure. In this setting, the results of systemic treatment today remain limited, but a huge effort in the molecular biology field has been done to introduce targeted therapy into this domain of head and neck cancer. Disease control remains variable within the patient population. This variation can increasingly be predicted by systems that incorporate the combined information of multivariately identified and quantified prognostic factors into an individualized prognosis for the parotid carcinoma patient.

Epithelial-myoepithelial carcinoma: a review of the clinicopathologic spectrum and immunophenotypic characteristics in 61 tumors of the salivary glands and upper aerodigestive tract

To further define the clinicopathologic spectrum of epithelial-myoepithelial carcinoma (EMCa), we report the gross, histologic, and immunophenotypic characteristics of 61 tumors seen within a 30-year-period. The mean age at presentation was 60.9 years, with a female predominance (1.5:1). The most common sites were parotid (62.1%), sinonasal mucoserous glands (10.3%), palate (8.6%), and submandibular (8.6%). Most EMCas showed a characteristic nodular/multinodular growth pattern and classic biphasic tubular histology. However, new morphologies in EMCa such as ancient change (8.2%), "Verocay"-like change (3.3%), and sebaceous differentiation (13.1%) were noted. Specific histologic variants were dedifferentiated EMCa (3.3%), oncocytic EMCa (8.2%), EMCa ex pleomorphic adenoma (1.6%), double-clear EMCa (3.3%), and EMCa with myoepithelial anaplasia (3.3%). All cytokeratin cocktails selectively highlighted the epithelial component well. Of the myoepithelial markers, p63, smooth muscle actin and vimentin performed best. Bcl-2 and c-kit were frequently positive (66.7% and 69.2%, respectively). p53 was highly expressed only in 1 dedifferentiated EMCa. The recurrence rate was 36.3% (median disease-free survival 11.34 y), but death was rare with 5-year and 10-year disease-specific survivals of 93.5% and 81.8%, respectively. The most important univariate predictors of recurrence were margin status (log rank P=0.006), angiolymphatic invasion (P=0.002), tumor necrosis (P=0.004), and myoepithelial anaplasia (P=0.038). Thus, EMCa is generally a low-grade tumor with a broader morphologic spectrum than previously thought, with several key features predictive of recurrence. Immunohistochemistry can aid diagnosis by highlighting the biphasic nature of the tumor.

Epithelial–myoepithelial carcinoma of the submandibular gland with symptomatic lung metastases treated with chemotherapy

This report concerns a patient with symptomatic lung metastases from an epithelial-myoepithelial carcinoma of the submandibular gland. Although the efficacy of chemotherapy is unknown in this disease, our patient was treated with cisplatin combined with 5-fluorouracil and later with paclitaxel and cyclophosphamide. Chemotherapy allowed disease stabilization and relief of the pulmonary symptoms. This is the first report on the use of chemotherapy in this very rare salivary gland carcinoma.

Epithelial-myoepithelial carcinoma in the base of the tongue: a case report

OBJECTIVES

To report a rare case of epithelial-myoepithelial carcinoma (EMC) of a minor salivary gland originating in the base of the tongue, which is a highly unusual location.

STUDY DESIGN

This is a case report and a review of literature.

METHODS

A 76-year-old man was referred to our outpatient clinic with a 6-month history of a sensation of a foreign body in the pharynx. Endoscopic examination revealed a tumorous lesion 40 x 20 mm in the base of the tongue on the left side. A biopsy was performed, and the lesion was histologically identified as squamous cell carcinoma.

RESULTS

The patient underwent subtotal glossectomy, bilateral neck dissection, and reconstruction with a microvascularized rectus abdominis myocutaneous flap. The final diagnosis based on the histological and immunohistochemical findings was EMC. Because neither histological evidence of residual tumor in the surgical margin nor neck metastases were found, radiotherapy was not performed. No local recurrence or distant metastases have been found 19 months post-surgery.

CONCLUSION

We believe this report is the first description of EMC originating in the base of the tongue. We conclude that a wide surgical excision with a clear margin and close, prolonged follow-up are recommended for the treatment of EMC.

Epithelial-myoepithelial carcinoma of the parotid gland

We report a rare case of epithelial-myoepithelial carcinoma (EMC) of the parotid gland. A 70-year-old man presented with a 4-months-history of right-sided subauricular swelling. Computed tomographic scans revealed a well-defined mass with cystic lesion, measuring about 40 mm in diameter, in the right parotid gland. Because the tumor occupied superficial lobe, he underwent superficial parotidectomy with preservation of the facial nerve. On the basis of the histological and immunohistochemical findings, the tumor was diagnosed as EMC. His post-operative course was uneventful, and he is currently free from disease 6 months after surgery. Diagnosis, clinical behavior and treatment of EMC are reviewed from perusal of the literature.

Epithelial-myoepithelial carcinomas of the bronchus

Epithelial-myoepithelial carcinomas are very rare in the lung, and little is known about the relationship of their histologic features to prognosis. We describe five primary pulmonary epithelial-myoepithelial carcinomas with details on clinical presentation, histology, and immunohistochemical profiles. We also reviewed the literature to detail further their prognosis. The patients' ages ranged from 33 to 57 years (average 51 years). The tumors were all endobronchial and the patients presented with symptoms or imaging features of airway obstruction. The tumors were completely resected; none showed nodal involvement. All five patients are alive and free of disease 4 months to 8 years (average 4.2 years) after surgery. Four tumors showed a mixed pattern of glands lined by a dual layer of cells and solid sheets of either spindle cells or clear cells, the glandular and solid components being present in variable proportions. The fifth tumor comprised purely spindle cells. The mitotic rate was <1/20 high power fields in both the glandular and spindle/clear cell components. In one case there was focal nuclear pleomorphism. The inner layer of the glands stained for cytokeratins and epithelial membrane antigen, and the outer layer for S-100 and smooth muscle actin. In one case the spindle cells stained for CD34. A review of published cases shows the majority of tumors behave in an indolent fashion, the rare aggressive tumors being predominantly myoepitheliomatous. Nevertheless, the term epithelial-myoepithelial carcinoma is preferred because of their malignant potential. A high mitotic rate, tumoral necrosis, and nuclear pleomorphism appear to be adverse prognostic factors.

Pulmonary Epithelial-Myoepithelial Tumor of Unproven Malignant Potential: Report of a Case and Review of the Literature

Epithelial-myoepithelial tumors of the lung are rare neoplasms whose biological behavior and clinical course still remain to be defined. A case of epithelial-myoepithelial tumor of the lung arising from bronchial mucosa-submucosa and occurring as a polypoid lesion of the upper left bronchus in a 47-year-old man is reported. The tumor did not infiltrate the cartilaginous wall of the bronchus and showed a biphasic histological appearance with a double layering of epithelial and myoepithelial cells. Myoepithelial spindle cells with eosinophilic cytoplasm were also observed. Mitotic figures were very rare and necrosis absent. Immunohistochemical study for epithelial and muscular markers confirmed the presence of a double-cell component in the tumor, namely epithelial and myoepithelial. The patient is alive and well, with no evidence of recurrent or metastatic disease 6 months after surgery. On the basis of the present case and the six previously reported cases, we suggest using the noncommittal term pulmonary epithelial-myoepithelial tumor of unproven malignant potential (PEMTUMP) for this type of neoplasm. In addition, we first introduce p63 as a novel marker for highlighting the myoepithelial cells of the respiratory tract and speculate on the role of these cells in the development of this unusual tumor.