Malignant myoepithelioma of the external auditory canal - a rare case report with literature review and clinical importance of foramen of Huschke.

BACKGROUND: A malignant myoepithelioma is a rare tumor, mostly arising from the salivary glands. Myoepitheliomas of the ear have rarely been reported. The manuscript reports myoepithelial carcinoma of the external auditory canal (EAC) spreading to the infratemporal fossa. A clinician must be aware of anatomical variation of the bony EAC wall, such as the foramen of Huschke. This rare defect may be a pathway for spreading pathologies between these two anatomical regions. CASE REPORT: We present a case of osteoma-like stenosis of the EAC, which turned out to be an extremely rare malignant tumor. The preoperative MRI and PET/CT revealed that two parts of the tumor communicated through a defect in the antero-inferior portion of the bony ear canal. No distant metastases were detected. Subsequently, the tumor was resected from the ear canal and the infratemporal fossa en bloc. Perioperatively the defect in the EAC wall was suspected of the foramen of Huschke. After the surgery, the older scans of the patient from the past showed no presence of a congenital EAC wall defect. Therefore, the authors concluded that the tumor aggressively grew through the bone due to its biological nature. CONCLUSION: Malignant myoepithelioma of the external auditory canal is an extremely rare condition and could be misdiagnosed as other benign lesions. In cases of suspicious lesions, it is advisable to do a probatory biopsy from the EAC. Surgery is the treatment of choice in malignant myoepitheliomas, and regular follow-ups are essential to monitor for recurrence or metastatic disease. Any mass located at the antero-inferior portion of the EAC wall warrants close evaluation due to its potential for expansion from the EAC.

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.

Spindle-cell myoepithelioma: A rare case in a finger of a 15-year-old boy.

Cutaneous myoepithelioma is a rare neoplasm of the skin that has become more widely recognized in recent years despite significant diagnostic pitfalls. It is a benign neoplasm with a high recurrence rate if not excised radically, and must be distinguished from its malignant counterpart. Few cases have been described so far and, to our knowledge, no cases in the finger of a child exist in the literature. We report the case of a 15 year-old boy affected by a rare form of locally aggressive spindle-cell myoepithelioma, and suggest a new multidisciplinary approach combining surgical excision and custom brachytherapy.

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.

Epithelial-myoepithelial carcinoma of retro-molar trigone: Unveiling the mystery of rare diagnosis.

Epithelial-myoepithelial carcinoma (EMC), a low-grade malignant neoplasm of glandular origin, most commonly involves major and occasionally minor salivary glands. It is rare in minor salivary glands such as hard and soft palate, buccal mucosa, tongue, and so on, frequently affecting geriatric females. EMC comprises diverse histo-pathologic features of an epithelial, myoepithelial de-lineating biphasic pattern along with clear cells, sometimes oncocytic differentiation. Aberrant histo-pathologic features in EMC need judicious discrimination from alike entities, which facilitates appropriate surgical management. Here, we present an unusual case report of EMC in the left retro-molar trigone region in a 60-year-old male patient, the complete diagnosis of which was based on clinical, radiological, histo-pathological, and immuno-histo-chemical features.

Ectomesenchymal chondromyxoid tumor of the oral cavity: a report of 5 new cases with comprehensive review of the literature and clinicohistopathologic features.

OBJECTIVE: An ectomesenchymal chondromyxoid tumor (ECT) is an uncommon soft tissue tumor with an enigmatic histogenesis and striking predilection for the tongue. We present 5 new cases and review the literature. STUDY DESIGN: We performed a retrospective search for ECTs within the University of Kentucky Oral Pathology Biopsy Service and the published literature. RESULTS: Five new cases from the biopsy archives and 103 well-documented ECT cases from the literature were compiled and reviewed. Whereas 89.8% of ECT are found on the anterior/dorsal/lateral/unspecified tongue, 4.6% are on the posterior/base of tongue. Six extralingual cases are reported. The age ranges from 2.3 to 78 years with an average of 40. Most ECT react with GFAP (92.8%) and S-100 protein (91.3%). Whereas 21/23 cases demonstrated a RREB1-MKL2 fusion, EWSR1 gene mutations are identified in 4 cases. CONCLUSIONS: Most ECT are readily diagnosed on routine histopathology in combination with tumor site, immunohistochemical findings, and molecular findings; however, a subset share overlapping features with myoepithelioma of soft parts. As further molecular analysis is performed on this tumor, we may find that a subset of previously diagnosed ECT relate to or represent myoepithelioma or conversely fall under the spectrum of the pluripotent ECT.

Intraoral exophytic lesion in an adolescent: A case report of myoepithelioma with unique clinical presentation.

Myoepithelioma is an infrequent benign tumor of the salivary glands, characterized by its composition of myoepithelial cells which can show different shapes and be arranged in various patterns with a well-circumscribed or encapsulated growth. This tumor commonly presents in adults as an asymptomatic swelling of the parotid gland, very rarely in minor salivary glands of children or adolescents, and even rarer in the buccal mucosa, with only six cases reported to date and only one of them presented in an adolescent. We present an additional case of myoepithelioma in the buccal mucosa of a 16-year-old male, with a novel clinical presentation as a non-submucosal exophytic mass. Immunohistochemically, neoplastic cells were positive for CK, S100, p63, and GFAP. The tumour was treated surgically, and the patient showed satisfactory evolution at 1 year of follow-up. The clinical and histopathological characteristics of the reported cases are discussed.

Primary Epithelial-Myoepithelial Carcinoma of the Lung Presenting as Multiple Synchronous Lesions.

Primary epithelial-myoepithelial carcinoma of the lung is an extremely rare histologic form that originates in the bronchial glands. Pulmonary epithelial-myoepithelial carcinoma in the peripheral lung is extremely rare, and multiple primary pulmonary epithelial-myoepithelial carcinoma has not been reported to date. Here, we report a case of pulmonary epithelial-myoepithelial carcinoma presenting as multiple synchronous lesions. The patient underwent two treatments by video-assisted thoracic surgery within 3 years. At the 4-month follow-up, the patient had no evidence of recurrence. In conclusion, our case report may contribute to the understanding of pulmonary epithelial-myoepithelial carcinoma.

Epithelial-myoepithelial carcinoma of the maxillofacial and sinonasal region: a systematic review of presenting characteristics, treatment modalities, and associated outcomes.

Epithelial-myoepithelial carcinoma (EMC) is a rare salivary gland malignancy. Controversy exists in the literature regarding the effectiveness of treatment modalities employed in the management of EMC. This systematic review was undertaken to understand the presenting characteristics of EMC and identify the most common treatment modalities and their associated outcomes, in order to help guide an evidenced-based approach to the algorithm of care. The MEDLINE (PubMed) and Embase databases were searched (up to February 23, 2022), and the review was performed in accordance with the PRISMA statement. Fifty-seven studies (51 case reports and six case series) describing 91 cases of EMC were included in this review. In the included studies, a slow-growing painless mass was the most common presenting clinical feature. EMC was most frequently treated with surgery alone (65%). Local disease recurrence occurred in 24% of the cases and metastatic disease in 11%. A positive surgical margin was found to be associated with a higher risk of recurrence (P < 0.001), while adjuvant radiotherapy was associated with a decreased risk of local disease recurrence (P = 0.034). Metastatic disease and multimodal therapy were found to be associated with decreased disease-free and overall survival (all P < 0.05). The current literature supports surgery with clear margins as the mainstay of treatment for EMC of the salivary and seromucous glands of the head and neck. In certain situations, radiotherapy may improve disease-free survival.

Malignant breast myoepithelioma: A systematic review.

OBJECTIVES: We performed a systematic review in order to describe the clinical presentation, therapeutic management and outcomes of malignant myoepitelioma of the breast. SEARCH STRATEGY: A systematic search of MEDLINE and EMBASE references from January 1980 to Marsh 2020 was performed. We included articles that reported cases of malignant breast myoepithelioma. Data from eligible studies were independently extracted onto standardized forms by two reviewers. RESULTS: 31 articles including 47 cases of malignant breast myoepithelioma and 3 other unpublished cases managed in our establishment were included in this systematic review. The average age at diagnosis was 60.7 years old [range 30-81]. The average size of the tumor was 46mm [range 10 -230]. 30 patients had a partial mastectomy and 18 a total mastectomy. Only 15% of patient (7/48) had an axillary sentinel lymph node biopsy of whom one was positive. 33% of patients (16/48) had an axillary lymph node dissection which was positive for one patient. 19% (n=9) had adjuvant radiotherapy and 15% (n=7) had adjuvant chemotherapy. 33% (n=10) of patients with partial mastectomy had at least one recurrence, versus 5.5% (n=1) after a total mastectomy. The average time between the diagnosis and the first recurrence was 25.4 months [range: 1-50]. 64% (n=7) had a second partial mastectomy and only 18% (n=2) had a total mastectomy. 27% of patient had chemotherapy after their first recurrence and 27% had radiotherapy if it was not received in first line treatment. 40% (n=4/10) of patients with partial mastectomy who recurred have had at least 2 breast recurrences. 28% (n=14) of all patients had distant metastases. 20% of patients (n=10) died whose 80% (n=8) had distant metastatic disease. CONCLUSIONS: This systematic review provided a precise summary of the clinical characteristics and treatment of patients presenting with Malignant breast myoepithelioma in the past 40 years. We anticipate that these results will help inform current investigations and treatment.

Primary pulmonary epithelial-myoepithelial carcinoma: Report of a rare and under-diagnosed low-grade malignancy.

Primary epithelial-myoepithelial carcinoma (EMC) is a rare low-grade malignant neoplasm of the lung that originates from the submucosal bronchial glands. It behaves in an indolent fashion, although rare cases with high-grade transformation have been reported. Because of the rarity, optimal therapy for this entity has not been clearly defined. Herein, we report a case of primary pulmonary EMC in a 38-year-old Indian man who had a short history of dyspnea and a computed tomographic (CT) scan revealed a 3 cm diameter homogeneous mass in the lower lobe of the right lung. A CT-guided biopsy revealed a mildly atypical and mitotically quiescent tumor with solid and focal acinar arrangement; foci with biphasic arrangement by inner epithelial and outer myoepithelial cells were identified. The neoplasm revealed cytokeratin (CK) 7 positivity in the epithelial cells, while the myoepithelium expressed smooth muscle actin and p63. The tumor had a low (8%) Ki-67 proliferation index. The neuroendocrine markers, thyroid transcription factor 1, CK5/6, p40, and napsin A were negative. Positron emission tomography-CT was negative for any other mass lesion. The mass was excised with negative margins and the patient was on close follow without any evidence of disease for the past 17 months. A custom made, targeted DNA- and RNA-based 5 gene lung cancer next-generation sequencing panel (Epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), Ros protocol-oncogene 1 tyrosine kinase (ROS1), B-rapidly accelerated fibrosarcoma family oncogene (BRAF), and mesenchymal epithelial transition molecule (MET)), compatible with the Ion S5 system was performed; however, no mutation was identified. This case depicts awareness about this entity and use of appropriate immunostains, particularly the myoepithelial markers are essential to arrive at a correct diagnosis. Importantly, high-grade transformation, recurrence, and metastases are not very uncommon in EMC, warranting a correct and timely diagnosis for therapeutic decision-making and prognostication of the patient.

Tracheal myoepithelioma resected by using rigid bronchoscopy: a case report and review of the literature.

BACKGROUND: Endotracheal tumors are rare in the respiratory system. Myoepitheliomas are benign tumors, which are rarely reported in the respiratory system. Herein, we report a rare case of endotracheal myoepithelioma, which was resected by rigid bronchoscopy. CASE PRESENTATION: A 36-year-old man, presenting with chest pain, dyspnea, stridor, and hemoptysis, was referred to our center with radiological features of near-total tracheal obstruction due to mass. Fiberoptic bronchoscopy with argon plasma coagulation and rigid bronchoscopy with grasper forceps was utilized to resect the mass. Pathological evaluation of the mass demonstrated myoepithelioma. The patient was discharged in good condition. Now, after 6 months, the patient is symptom-free with no evidence of tumor recurrence or re-growth. CONCLUSIONS: Despite being extremely rare, myoepithelioma should be considered a possible differential diagnosis for endotracheal tumors. Fiberoptic and rigid bronchoscopy management is an effective method for the resection of endotracheal tumors.

Myoepithelioma-like tumors of the vulvar region: A case report and review of the literature.

Myoepithelioma-like tumors of the vulvar region (MELTVR) is a kind of solid tumor newly recognized in recent years, which is characterized by mesenchymal tumors of adult female vulva. The histopathology is similar to myoepithelioma, but the immunohistochemical phenotype and genetic changes are different from myoepithelioma. It usually has clear boundary and partial capsule, mixed with two forms of cells (epithelioid and spindle), the cells are mild, the nucleoli are clear, mitoses are rare, some cases have myxoid differentiation. In this article, a case of MELTVR diagnosed in our hospital is discussed. The patient was a 43-year-old female who finds a neoplasm in the pubic tubercle 4 months ago. Local resection was performed. Pathological examination showed that the boundary of the tumor was clear with partial capsule. The cells were arranged in cords or nests, and partially infiltrated the surrounding adipocytes. The tumor cells had two morphologies, epithelioid or spindle shaped. The spindle type cells were dominant, with bright cytoplasm, obvious nucleoli, rare nuclear mitosis (about 1/10HPF), and no necrosis was observed. Immunohistochemically, the tumor cells were positive for vimentin, epithelial membrane antigen, estrogen receptor, progestogen receptor, calponin and were partially positive for cathepsin k. INI1/SMARCB1 expression was deficient. There was no recurrence or metastasis during the 8-month-long follow-up. The unique feature of this case was that the site of the disease was not the vulva, but in front of the pubic tubercle, there was no large amount of mucus production, and the cytoplasm of most tumor cells was transparent. Due to our limited knowledge of MELTVR, its pathogenesis and tissue origin are not clear. Clinicians should be aware of such potential patients.

Progresión locorregional de carcinoma mioepitelial de la mama postratamiento quimiorradioterápico. Resección y cobertura con colgajo de avance / Locoregional progression of myoepithelial carcinoma of the breast after chemotherapy and radiotherapy. Resection and coverage with advancement flap

El carcinoma mioepitelial de la mama es un tumor infrecuente, con pocos casos descritos en la literatura, por lo que su diagnóstico es difícil y su tratamiento un desafío que incluye el diseño de colgajos locales. Presentamos un caso clínico de carcinoma mioepitelial de mama con progresión locorregional tras quimioterapia y radioterapia, así como una revisión de la literatura que nos permiten establecer un diagnóstico definitivo y un tratamiento óptimo oncológico y quirúrgico con reconstrucción de este tumor.(AU)

Myoepithelial carcinoma of the breast is an uncommon tumour with few cases reported in the literature. Consequently, it is a diagnostic and therapeutic challenge. Treatment includes the design of local flaps. We present a case of myoepithelial carcinoma of the breast with locoregional progression after chemotherapy and radiotherapy. We also provide a review of the literature, allowing us to establish a definitive diagnosis and optimal oncological and surgical treatment with reconstruction of this tumour.(AU)

Malignant Adenomyoepithelioma of the Breast and Associated Epithelial-Myoepithelial Carcinoma; A Rare Case Report.

Adenomyoepithelioma comprises a spectrum of lesions with variable morphology and clinical behavior, presenting at a wide age range. The most common presenting symptom is palpable abnormality. Mammographic abnormalities include focal asymmetries, masses and microcalcifications. Adenomyoepithelioma is a biphasic neoplasm characterized by proliferation of epithelial and myoepithelial cells. Adenomyoepitheliomas can be benign, atypical and malignant (adenomyoepithelioma with carcinoma). Malignant transformation occurs in either one or both cellular components leading to the development of invasive carcinoma. Invasive carcinoma types include invasive breast carcinoma of no special type, invasive lobular carcinoma, invasive carcinoma of special types, myoepithelial carcinoma, metaplastic carcinoma and biphasic carcinoma such as epithelial-myoepithelial carcinoma. While the majority of classic adenomyoepitheliomas have a benign clinical course and can be treated by local excision, local recurrence and distant metastasis have been reported. In malignant cases, treatment is determined by the associated carcinoma to include radiotherapy after breast conserving surgery and sentinel lymph node biopsy or axillary lymph node dissection, as indicated. Herein we report a case of a 62 year old woman who was found to have focal asymmetry on screening mammogram. She underwent a core biopsy of the lesion which showed atypical epithelial-myoepithelial neoplasm and excision was recommended. Upon excision, a diagnosis of malignant adenomyoepithelioma with associated epithelial-myoepithelial carcinoma was rendered with negative margins. The patient declined additional surgery for sentinel lymph node biopsy and declined adjuvant therapy. Six months after surgery, the patient is doing well with no complains. A follow-up mammogram and ultrasound of the axilla showed no abnormalities.

Myoepithelioma-like tumour of the vulval region: A case report.

Myoepithelioma-like tumours of the vulvar region (MELTVR) are a newly described group of spindle cell neoplasm. Morphologically, they consist of epithelioid to spindled cells in a myxoid to collagenous stroma and can resemble epithelioid sarcomas, myoepithelial carcinomas or extraskeletal myxoid chondrosarcomas. However, they have a distinct pattern of immunohistochemical staining characterised by positivity for EMA, ER, PR and negativity for cytokeratin, GFAP and S100. Nuclear staining for INI-1 is lost. In addition, they lack the characteristic gene arrangements of these other lesions. MELTVR can recur locally when incompletely excised, however, do not appear to metastasize. We report a case of a MELTVR in a 49-year-old woman arising in the right mons pubis.

Atypical presentation of invasive myoepithelioma in a pediatric patient.

A 15-year-old girl presented with a mobile lesion with yellowish hue on the posterior lamella of the right lower eyelid adjacent to the punctum. Four years prior, a lesion thought to be a chalazion was excised from the same location. There was subsequent progressive painless enlargement. The patient ultimately underwent an internal excision of the mass. Histopathology demonstrated infiltrative nests and cords of epithelioid and plasmacytoid cells with abundant eosinophilic myxoid-collagenous stroma along with focal infiltration of skeletal muscle with immunohistochemical staining consistent with an invasive myoepithelioma of mixed-cell type. Given concern for invasive disease, the patient underwent subsequent Mohs resection resulting in a 25% full thickness eyelid defect, which was repaired with direct closure of the wedge defect. There has been no recurrence of the disease for 7 months since the Mohs resection. This case illustrates the atypical presentation of an invasive myoepithelioma of the eyelid in a pediatric patient.

[Myoepithelial carcinoma of the parotid gland: a rare tumor with diagnostic challenges]. / Myoepitheliales Karzinom der Glandula parotis: Ein seltener Tumor mit diagnostischer Herausforderung.

We report on the occurrence of a myoepithelial carcinoma (MC) of the parotid gland in a 58-year-old female patient, 6 years after total parotidectomy of a locoregional myoepithelioma. Due to the rapid growth in the former resection area, panendoscopy and tumor extirpation of the right parotid region were performed. From a histomorphological and cytomorphological point of view, a hyalinized clear cell carcinoma of the salivary gland was originally diagnosed. After further immunohistochemical investigations and preparation of deeper section levels the morphological picture and immunohistochemical expression pattern corresponded to a myoepithelial carcinoma of the salivary gland, with focal lateral excision margins. Based on the radiological impression of suspicious lymph nodes during the staging examinations and the perineural invasion in the histological findings, modified radical neck dissection of the ipsilateral levels I-V was performed. All lymph nodes were histologically negative. An adjuvant radiotherapy was then initiated. The patient is tumor-free 7 months after surgery and after completing the adjuvant radiation treatment. Clinical assessment of the facial nerve showed House-Brackmann grade 5 facial palsy. The aim of this case report is to describe the difficulties in the diagnostics and treatment of this rare entity.