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

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.

[Primary malignant salivary gland-type tumors of the lung: clinico-pathological study of 10 cases]

Primary pulmonary salivary gland-type tumors are rare and characterized by a specific clinico-pathological manifestation. They are proximal tumors affecting young subjects and not associated with smoking. For optimal management, it is important to distinguish them from other bronchopulmonary tumors, with which they don´t share either biology or treatment and outcome. We conducted a retrospective study, including all primary malignant salivary gland-type tumors of the lung, over a period of 32 years, from January 1987 to December 2019. We collected data from the medical records of 10 patients: 5 men and 5 women (sex ratio 1). The average age of our patients was 47.4 years. In all cases radiological examinations showed proximally located nodular tumor ranging in size from 1 to 5.8 cm. Histological examination objectified mucoepidermoid carcinoma (6 out of 10 cases). All patients had localized or locally advanced tumors, with the exception of one case of metastatic mucoepidermoid carcinoma. Pulmonary salivary gland-type tumors correspond to a heterogeneous group of tumours. They are not very aggressive but are associated with a high frequency of recurrences and late metastases, requiring long-term monitoring.

Salivary Gland-type Tumors of the Lung

CONTEXT.—

Salivary gland-type tumors (SGTs) of the lung represent a distinct group of lung neoplasms. Pulmonary SGTs often pose diagnostic challenges, especially in small biopsy and cytology samples because of limited sample volume and overlapping morphology among pulmonary SGTs, metastatic SGTs of head and neck origin, and other lung tumors.

OBJECTIVE.—

To identify the clinical characteristics, histomorphology, immunophenotypic features, and molecular alterations that are crucial for the diagnosis and differential diagnosis of pulmonary SGTs, especially in small biopsy and cytology specimens.

DATA SOURCES.—

Literature review and authors' personal practice experience.

CONCLUSIONS.—

An accurate diagnosis of pulmonary SGTs can be achieved by careful evaluation of clinical findings and histomorphology in conjunction with immunohistochemical studies and molecular analysis.

[A Rare Case of Pulmonary Epithelial-myoepithelial Carcinoma: Case Report and Literature Review]

背景与目的

肺上皮-肌上皮癌（pulmonary epithelial-myoepithelial carcinoma, P-EMC）是一种十分罕见的涎腺型肺肿瘤，尚无标准治疗方案，本文拟分析肺上皮-肌上皮癌的临床特点，探讨肺上皮-肌上皮癌的诊疗方案。

方法

分析1例肺上皮-肌上皮癌患者的临床资料并回顾其他相关临床文献。

结果

上皮细胞免疫组化表达细胞角蛋白，肌上皮细胞免疫组化表达SMA及S-100，二代基因测序以HRAS基因突变为主，PD-L1蛋白为阴性。

结论

肺上皮-肌上皮癌大多预后良好，诊断以镜检及免疫组化为主，治疗以手术切除为主，放化疗效果尚不明确。

The First Reported Pediatric Case of Primary Myoepithelial Carcinoma Involving the Whole Lung: Surgical Radical Treatment and Prosthesis Implant

Primary myoepithelial carcinoma of the lung (PMC-L) arising from the bronchial glands in lower respiratory tract is exceedingly rare. Thus far, few cases in adults and only one in a pediatric patient have been recorded. To our knowledge, this is the first report of PMC-L successfully removed in a child, focusing on the importance of multidisciplinary primary surgery for the treatment of this tumor. A 7-year-old girl was admitted for persistent cough and fever; she was unresponsive to oral antibiotics. Chest radiography showed loss of volume of left lung sustained by almost total atelectasis. After routine clinical investigations, she was referred for computed tomography scan and magnetic resonance imaging that documented the presence of a mass occupying the entire left upper lobe, infiltrating the pulmonary hilum (main bronchus, pulmonary artery, superior pulmonary vein, and pericardium). After multidisciplinary evaluation, the histopathologic diagnosis of PMC-L was established using ultrasonography-guided transthoracic core needle biopsy and bronchoscopic biopsies. She was then subjected to left pneumonectomy under extracorporeal circulation and positioning of a thoracic expander filled with 200 mL of saline solution. The postoperative course was uneventful. With TREP (very Rare Tumor in Pediatric Age) consent radiotherapy was performed (61.2 Gy). At the 10-month follow-up, the patient was alive, breathing normally without any oxygen support, without recurrence of PMC-L or metastasis, and without any chest deformity. To our knowledge, this is the first case where a pediatric patient was successfully operated for PMC-L involving the whole lung. Extracorporeal circulation enabled us to perform radical primary surgery. Prosthesis implant not only maintained normal chest expansion but also allowed focused radiotherapy, thus enabling us to prevent damage to vital organs.

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.

Sinonasal epithelial-myoepithelial carcinoma: Report of a novel subsite and review of the literature

BACKGROUND

Epithelial-myoepithelial carcinoma (EMC) is a rare tumor of the major and minor salivary glands. Sinonasal EMC is extremely uncommon and hitherto not described within the frontal or ethmoid sinuses.

OBJECTIVE

To present a novel sinonasal subsite and review the literature regarding sinonasal EMC.

METHODS

A case of frontoethmoidal EMC was presented. A medical literature data base was queried from January 1, 1950, to August 8, 2017, for all reports of sinonasal EMC.

RESULTS

A 69-year-old man underwent combined open and endoscopic craniofacial resection of a right frontoethmoidal EMC, a previously undescribed primary location for this tumor. A comprehensive review of the literature revealed 13 additional cases of sinonasal EMC.

CONCLUSION

EMC is an uncommon neoplasm typically found in the major salivary glands; occurrence in the nose or paranasal sinuses is extremely rare. EMC often follows an indolent clinical course, although, in a minority of cases, particularly in large tumors with nuclear atypia, more aggressive behavior may be observed.

First case report of a curative wedge resection in epithelial-myoepithelial carcinoma of the lung

Epithelial-myoepithelial carcinoma is a well differentiated malignant neoplasm, which originates from the salivary glands. The primary pulmonary manifestation is rare-about 30 cases have been reported worldwide. In the literature, anatomical resection has been described as the standard surgical approach. In the presented case, a wedge resection was performed, with no evidence for tumor relapse in the follow-up reevaluation after 24 months. This is the first case report of a primary pulmonary epithelial-myoepithelial carcinoma that has been treated with a non-anatomical wedge resection and lymph node dissection as a curative approach.

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.

A rare case of primary peripheral epithelial myoepithelial carcinoma of lung: Case report and literature review

BACKGROUND

Primary salivary gland-type tumors of lung are rare. Epithelial-myoepithelial carcinoma (EMC) of the lung is a minor salivary gland-type tumor subtype.

METHODS

We report a very rare case of EMC located in the peripheral left lower lobe that was diagnosed in a 58-year-old man and this is the first study in which we summarize all the patients with primary peripheral lung EMC concerned with the clinical features. Informed consent was obtained from the patient.

RESULTS

Chest computed tomography displayed an anomalous soft tissue mass with slightly lobular borders in the peripheral segment of the left lower lobe and closed to the visceral pleura. The surgery was performed by using video-assisted thoracic surgery. Grossly, the tumor was solitary, well-circumscribed, and unencapsulated endobronchial lesion. A microscopic examination revealed that it was circumscribed, although the tumor borders may show single cells or clusters of cells proliferating away from the main tumor mass. The inner tubular layer showed epithelial cell characteristics, whereas the outer layer exhibited myoepithelial cell characteristics. Immunostaining for P40, P63, and cytokeratin 5/6 was positive. However, the anaplastic lymphoma kinase-V, thyroid transcription factor-1, synaptophysin, chromogranin A and napsin A were negative.

CONCLUSIONS

Literature review showed that most of patients with peripheral EMC were asymptomatic. Computed tomography and magnetic resonance imaging scans are able to indicate the presence of peripheral EMC. Pathological analysis is an effective method to clarify the diagnosis. Surgery is a regular treatment method. To facilitate the preoperative diagnosis and avoid the misdiagnosis of such a rare disease, more cases will need to be reported.

Primary epithelial-myoepithelial carcinoma of the lung: A case report demonstrating high-grade transformation-like changes

Primary salivary gland-type tumors of the lung are rare; among them, epithelial-myoepithelial carcinomas (EMC) represent a minor histological subtype. The present case documents an EMC that occluded the B8 segment of the left lung in a 72-year-old woman. Macroscopically, the tumor was well-demarcated; however, microscopic examination demonstrated that it had infiltrated the lung parenchyma. The majority of the tumor mass was composed of a myoepithelial overgrowth in conjunction with conventional bilayered ductal structures comprising epithelial and myoepithelial cells. At the advancing edge of the tumor, the myoepithelial overgrowth was observed to be gradually transitioning to a higher-grade component, which demonstrated venous invasion. The Ki-67 labeling index was reduced compared with high-grade transformation (HGT) of salivary gland EMC; p53 was sparsely observed on immunostaining. However, cyclin D1, which is reported to be overexpressed in certain subtypes of salivary gland carcinomas with HGT, was overexpressed in the higher-grade component of the tumor, indicating a potential HGT initiation. The surgical margin was tumor free, and no recurrence has been observed for 4 months. A thorough follow-up is required considering the HGT-like changes and venous invasion of the tumor. Additional studies are required to elucidate the characteristics of pulmonary EMC, with an emphasis on detecting HGT or HGT-like changes.

Tracheal epithelial-myoepithelial carcinoma associated with sarcoid-like reaction: A case report

Epithelial-myoepithelial carcinomas are rare tumors that primarily originate in the salivary glands but have also been found in the tracheobronchial tree. We report the first case of epithelial-myoepithelial carcinoma associated with sarcoidosis. A 61 year old Hispanic man presented with altered mental status and hypercalcemia. Imaging revealed diffuse intra-thoracic and intra-abdominal lymphadenopathy. A diagnostic bronchoscopy was performed where an incidental tracheal nodule was discovered and biopsied. Pathology was consistent with epithelial-myoepithelial carcinoma. Lymph node biopsy demonstrated non-caseating granulomas consistent with sarcoidosis. Patient underwent tracheal resection of the primary tumor with primary tracheal reconstruction. Hypercalcemia subsequently normalized with clinical improvement. Repeat CT imaging demonstrated complete resolution of lymphadenopathy. Our findings are suggestive of a possible paraneoplastic sarcoid-like reaction to the epithelial-myoepithelial carcinoma with associated lymphadenopathy and symptomatic hypercalcemia.

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.

A rare case of lung metastasis from a malignant adenomyoepithelioma of the breast: histological features and therapeutic implications

We present a rare case of lung metastasis from a malignant adenomyoepithelioma of the breast. A 44-year-old woman was surgically treated in 2008 for a malignant adenomyoepithelioma of the breast. Shortly after, two lung nodules were detected through a CT scan, and a diagnosis of malignant adenomyoepithelioma was rendered.