Myoepithelial carcinoma of soft tissue: a case report and review of the literature

Fine-needle aspiration cytology of retroperitoneal myoepithelial carcinoma: A rare encounter with diagnostic dilemmas

Myoepithelial carcinoma (MC) arises from the myoepithelial cells. It is a rare tumor with a predilection for salivary glands. MC in soft tissue is uncommon. Soft tissue MC exhibits dual epithelial and smooth muscle phenotype. The extremities and limb girdles are commonly affected. We present cytological findings of retroperitoneal MC with an accurate diagnosis being rendered with the aid of immunocytochemistry on the cell block and demonstration of EWSR1 rearrangements by fluorescence in situ hybridization on cytology smear. The smears were cellular, showing loose clusters and sheets of tumor cells embedded in dense eosinophilic to myxoid matrix material. The cells were oval to polygonal, with focal areas showing moderate nuclear pleomorphism, vesicular to coarse chromatin, and vacuolated cytoplasm with clearing. On immunocytochemistry, tumor cells were positive for epithelial membrane antigen, pan-cytokeratin, calponin, smooth muscle actin, and S-100. A literature review shows only a handful of cases of soft tissue MC. The current report emphasizes the need for cytomorphological awareness with the employment of ancillary testing for accurately diagnosing this rare tumor at an uncommon location. We also discuss the diagnostic challenges and troubleshooting.

Abdominal myoepithelial carcinoma: A rare abdominal wall entity of an uncommon tumor

Introduction and importance

Case presentation

Clinical discussion

Conclusion

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Extra-salivary myoepithelial carcinoma is an extremely rare entity, may present as an abdominal mass.

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In contrast to their salivary-gland counterparts, most of them are malignant to begin with.

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Limited data is available for their management, hence such patients should be enrolled in clinical trials whenever available.

Foot plantar soft tissue malignant myoepithelioma tumor: Case report and review of the literature

The spectrum of myoepithelial tumors usually occur in the salivary glands, and occasionally in the skin, breast, upper aero-digestive tract, and soft tissues. The myoepithelial tumors have no sex predominance and usually present within a wide range of age of distribution around the third and fifth decades. We describe a 12 year old male patient with primary malignant myoepithelial tumor in the foot plantar soft tissues. Including this tumor with unusual location, and age of presentation is essential in the differential diagnosis for soft tissue tumors in the pediatric population.

Adult soft tissue myoepithelial carcinoma: treatment outcomes and efficacy of chemotherapy

Soft tissue myoepithelial carcinomas are a rare, malignant subgroup of myoepithelial tumours mostly arising in the extremities with equal predilection for women and men. The mainstay of management of localised disease is complete surgical resection. Despite optimal treatment, 40-45% of tumours recur. Data regarding the efficacy of systemic therapy for advanced and metastatic disease are lacking. The primary aim of this study was to evaluate the outcome of all patients with soft tissue myoepithelial carcinoma treated at a single referral centre. The secondary aim was to establish the efficacy of systemic therapies in patients with advanced disease. A retrospective review of the prospectively maintained Royal Marsden Sarcoma Unit database was performed to identify soft tissue myoepithelial carcinoma patients treated between 1996 and 2019. Patient baseline characteristics and treatment history were recorded. Response to systemic therapy was evaluated using RECIST 1.1. We identified 24 patients treated at our institution between 1996 and 2019,12 males and 12 females. Median age at presentation was 49.6 years [interquartile range (IQR) 40.5-63.3 years]. Twenty-two out of 24 patients (91.7%) underwent primary surgical resection. Nine patients (37.5%) received systemic treatment. A partial response was documented in one patient treated with doxorubicin. The median progression-free survival for first-line chemotherapy was 9.3 months. Myoepithelial carcinoma frequently recurs after complete surgical resection. Conventional chemotherapy demonstrated some activity in myoepithelial carcinoma, however, more effective systemic therapies are required and enrolment in clinical trial should be encouraged.

Presumed choroidal metastasis from soft tissue myoepithelial carcinoma

Purpose

To report a case of presumed choroidal metastasis from soft tissue myoepithelial carcinoma and highlight challenges in its diagnosis.

Observations

A 52-year-old man was referred with a two-week history of photopsia in his left eye. His background medical history included known soft tissue myoepithelial carcinoma metastatic to his bone, lung, liver and chest wall. A large, raised, yellow choroidal lesion was identified nasal to and abutting the optic disc. This lesion demonstrated growth 1 month after presentation. The patient died with widespread metastatic disease 5 months after initial presentation.

Conclusion and importance

Soft tissue myoepithelial carcinoma can rarely metastasise to the choroid and present as a rapidly-growing, yellow, echodense tumour with serous retinal detachment. MRI brain can assist in tumour evaluation and monitoring progression, while immunoperoxidase stains and molecular testing can assist with diagnosis. The condition has an aggressive natural history and poor prognosis.