Bronchial epithelial-myoepithelial carcinoma

Pulmonary Epithelial-Myoepithelial Carcinoma

Pulmonary epithelial-myoepithelial carcinoma (P-EMC) is an exceptionally rare subtype of salivary gland lung tumor originating from tracheobronchial glands. P-EMC is a biphasic tumor consisting of an inner layer of epithelial cells and an outer layer of spindle-shaped, clear-cell-like myoepithelial cells. Bronchial obstruction symptom is the main clinical characteristic for P-EMC. Because its clinical and imaging characteristics are highly similar to other types of non-small-cell lung cancer (NSCLC), it is easy to cause missed diagnosis and misdiagnosis. The diagnosis is mainly based on the pathology and immunohistochemistry with an inner layer of epithelial cells immunoreactive for cytokeratin and an outside layer of myoepithelial cells immunoreactive for S100 protein (S-100) and smooth muscle actin (SMA). Therefore, positive for cytokeratin, S-100 and SMA can assist in the diagnosis. Although in general, P-EMC is a low-grade malignant neoplasm, it may occasionally recur and metastasize. The optimal method for P-EMC treatment has not been established, and surgical resection is still the main clinical method. Radiotherapy and chemotherapy have been shown not sensitive for P-EMC treatment, whereas targeted therapy and immunotherapy have not evaluated in clinical practice. This review focuses on the pathological characteristics, molecular characteristics, diagnosis, treatment, and prognosis of P-EMC.

Epithelial-myoepithelial carcinoma of the lung: a case report

BACKGROUND

Pulmonary epithelial-myoepithelial carcinoma (P-EMC) is a rare subset of salivary gland-type tumors of the lung. Because of its rarity and unproven malignant potential, the optimal therapy for P-EMC has not been defined. Here, we report a typical case of P-EMC and a review of the literature to consider appropriate treatment.

CASE PRESENTATION

A 54-year-old woman presented with an abnormal lung shadow on a routine chest X-ray. A chest computed tomography (CT) scan verified an 18-mm endobronchial nodule on the middle lobe. We performed a bronchoscopic biopsy, and the patient was diagnosed with P-EMC. After confirming the absence of tumors in the salivary glands, she underwent a right middle lobectomy along with hilar and mediastinal lymph node dissections. Currently, the patient is doing well, without any sign of recurrence 3 years after surgery.

CONCLUSIONS

Although a majority of P-EMC cases, as in our case, behave indolently, several poor progression cases have been reported. For distinguishing the minor malignancy cases from others, histological findings such as myoepithelial anaplasia could be a predictive factor. Complete resection is needed to evaluate the whole tumor, because P-EMCs often show histological heterogeneity. Moreover, incomplete excision may be a poor prognostic factor. Although lobectomies as well as lymph node dissections, sleeve lobectomies, or pneumonectomies are routinely performed for complete resection, further investigation is required to establish the optimal treatment strategy.

Hyalinizing clear cell carcinoma of the bronchial glands: presentation of three cases and pathological comparisons with salivary gland counterparts and bronchial mucoepidermoid carcinomas

Hyalinizing clear cell carcinoma of the bronchial glands is a very rare tumor. Since only five reports describing six tumors have been published to date, only a little is known about specific histologic findings and clinical features. Because of its rarity, hyalinizing clear cell carcinoma has not been described in the latest WHO classification of pulmonary tumors yet. Here we present three cases of bronchial hyalinizing clear cell carcinomas, confirmed by both fluorescence in situ hybridization (FISH) and RT-PCR, focusing on histologic and immunohistochemical characteristics in a comparison with three cases of salivary gland origin. In addition, we compared immunohistochemical features with bronchial mucoepidermoid carcinoma, a lesion that needs to be taken into account in differential diagnosis of hyalinizing clear cell carcinoma. All our bronchial hyalinizing clear cell carcinoma cases were surgically resected. Histologically, tumor cells showed clear to eosinophilic cytoplasm with hyalinizing stroma in various proportions, resembling those of salivary gland origin. Immunohistochemically, tumor cells were positive for CK7, CK5/6, p40, p63, and ATF1, while they were negative for TTF1, Napsin A, HMB45, and SOX10. The CK5/6 staining pattern varied in mucoepidermoid carcinomas, while that of hyalinizing clear cell carcinoma was uniformly positive. FISH revealed EWSR1-ATF1 fusion, and RT-PCR with sequencing confirmed specificity of the chimeric gene for hyalinizing clear cell carcinoma. Clinically, bronchial hyalinizing clear cell carcinoma was characterized by occurrence in the fourth to sixth decades, no link with smoking history, and a predilection for the right lung, in line with previous reports. In summary, our study confirmed that the bronchial hyalinizing clear cell carcinoma is a histologically and genetically identical tumor to that of salivary gland origin, and that gene rearrangement analysis can play a critical role in distinction from mucoepidermoid carcinoma.

Adenomyoepithelioma of the breast with late pulmonary metastases - case report and review of the literature

Background

Adenomyoepithelioma (AME) of the breast is a rare tumour of unpredictable clinical behaviour. Most of the tumours are benign with some giving local recurrences or distant metastases.

Case Presentation

We report a case of late lung metastases in a woman with a history of breast adenomyoepithelioma. Partial lobectomy was performed for lung lesions and initial diagnosis was epithelial-myoepithelial carcinoma.

Conclusion

Careful slide’s revision of both breast and pulmonary lesions showed identical microscopic appearance with lung tumour performing more malignant features. Tumour cells in both: breast and pulmonary lesions were positive for cytokeratin and EMA (epithelial cells) and also for SMA, S100 and vimentin (myoepithelial cells). Two years and 7 months follow-up showed no recurrent neoplastic disease in our patient.

Primary epithelial myoepithelial lung carcinoma

Primary epithelial-myoepithelial carcinoma (EMC) of the lung is an extremely rare neoplasm that originates from submucosal bronchial glands and has been found in the salivary glands, breast tissue, and sweat glands. However, only a few cases in the respiratory tract have been identified. In the literature, most pulmonary EMCs have been reported to have developed endobronchially although a few EMC cases have been presented as intraparenchymatous tumors. We have identified a case of primary EMC that developed in the peripheral lung parenchyma.

Primary epithelial myoepithelial carcinoma of lung, reporting of a rare entity, its molecular histogenesis and review of the literature

Primary epithelial myoepithelial carcinoma of lung is a rare entity and is thought to arise from the submucosal bronchial glands distributed throughout the lower respiratory tract. Because of the rarity of this tumor, we describe one case of epithelial myoepithelial carcinoma arising in the bronchus intermedius and presenting as an endobronchial mass. A 57-year-old male patient presented with an incidental finding of an endobronchial mass located in the lumen of the right lower lobe bronchus and caused near total luminal occlusion of the bronchus. An endobronchial carcinoid tumor was entertained clinically. Subsequently the patient underwent an uneventful videothoracoscopic lobectomy of lower and middle lobes of the right lung. Morphologically and immunohistochemically the tumor was characterized by two cell populations with epithelial and myoepithelial cells forming duct-like structure. The final diagnosis of epithelial myoepithelial carcinoma of lung was rendered.

Epithelial-myoepithelial tumour of the lung: a case report referring to its molecular histogenesis

Tracheobronchial submucous glands can be considered the pulmonary equivalent of minor salivary glands and therefore they can develop most of the tumours originated in these. Nevertheless, in spite of the wide distribution of this kind of glands along the tracheobronchial tree, pulmonary salivary gland-like neoplasms are not very frequent. Among them, the most frequent are mucoepidermoid and adenoid cystic carcinomas. On the contrary, pulmonary neoplasms showing a mixture of epithelial and myoepithelial elements are extraordinary infrequent, with only 11 cases collected from literature.

We present the case of a 76 year-old woman with no interesting pathological history, to whom a pulmonary nodule is detected during a study of unknown origin neutropenia. An upper right lobectomy is performed.

After macro and microscopic study, the diagnosis of pulmonary epithelial-myoepithelial tumour is made. It is a low malignant potential tumour with capacity to locally recur and less frequently to metastasize. Our case has the peculiarity of not being connected neither to visceral pleura nor to bronchial tree; we have not found this characteristic in any literature reviewed case.

These tumours have been named in a lot of different ways, including adenomyoepithelioma, epithelial-myoepithelial tumour, epithelial-myoepithelial carcinoma or epithelial-myoepithelial tumour of uncertain malignant potential.

The p27/kip-1 protein plays a fundamental role in the development of these neoplasms. As we have verified in our case, its aberrant cytoplasmic location, besides its proved oncogenic function, would favour the proliferation of stem cells, which would explain both dual phenotype with presence of myoepithelial cells without connection with the bronchial tree, and TTF-1 immunostaining in epithelial cells.

Epithelial-myoepithelial carcinoma of the lung. A case report and review of the literature

Primary lung tumors mimicking the salivary gland-type neoplasms are extremely rare. These types of tumors originate from submucosal bronchial glands. Epithelial-myoepithelial carcinoma is an uncommon tumor in this group, and only 7 cases have been reported. It is considered to be a low-grade malignant neoplasm. We report a case of epithelial-myoepithelial carcinoma of bronchial gland origin in a 73-year-old man who presented with coughing and dyspnea. The bronchus of the left lower lobe contained a tumor mass that had a polypoid growth pattern. The tumor also extended into the pulmonary parenchyma, forming a well-circumscribed mass with a pushing margin. The tumor consisted of epithelial and myoepithelial cells. The epithelial cells were positive for cytokeratins and epithelial membrane antigen, while the myoepithelial cells were positive for S100 protein and muscle-specific actin. According to these findings, we diagnosed epithelial-myoepithelial carcinoma. After undergoing pneumonectomy, the patient has been disease free for 34 months.

Epithelial and soft tissue tumors of the tracheobronchial tree

This article provides a broad overview of tumors that can involve the tracheobronchial tree. For the most part, the clinical, radiographic, and endoscopic presentation of these rare tumors does not differ significantly from the more common tumors of the lung. Appropriate classification of many tracheobronchial tumors ultimately requires complete sampling and a thorough microscopic evaluation. The introduction of ancillary diagnostic techniques such as immunohistochemistry and molecular analysis will continue to refine tumor classification.

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.

Myoepithelial carcinoma of the lung arising from bronchial submucosa

Myoepithelial neoplasm mainly occurs in the salivary glands and breasts and is extremely rare in the lung. To our knowledge, this report describes the first documented case of a myoepithelial carcinoma present in the lung. The tumor derived from the right main bronchial submucosa and exhibited a dual epithelial and smooth muscular phenotype by immunohistochemical and ultrastructural studies. It invaded the neighboring pulmonary tissue and the hilar lymph nodes. Despite a right pneumonectomy and chemotherapy, metastasis was found in the left lung 7 months later.

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

Epithelial-myoepithelial carcinomas (EMC) are rare neoplasms of the salivary gland with an incidence of less than 1% arising predominantly in the parotid gland. Although they are thought to be of low grade malignancy, fatal courses are described. We report a case of EMC of the parotid gland in a 58-year-old woman with an unfavorable course of this disease in long term follow-up. The malignant potential of this tumor is discussed. In addition, we include another case of EMC of the submandibular gland.