Malignant peripheral nerve sheath tumor of the breast: case report

<p>Abstract</p> <p>Background</p> <p>Malignant peripheral nerve sheath tumor is a rare soft tissue sarcoma of ectomesenchymal origin. It is the malignant counterpart of benign soft tissue tumors like neurofibromas and schwannomas and may often follow them. Common sites include deeper soft tissues, usually in the proximity of a nerve trunk. Breast is an extremely rare location of this lesion and presentation as a breast lump in the absence of pain or previous benign neural tumor is even rarer.</p> <p>Case presentation</p> <p>A 38-year-old female presented with complaints of painless, hard breast lump for three months which was clinically suspected to be a ductal carcinoma with inconclusive fine needle aspiration cytology. Histopathology revealed a malignant spindle cell tumor which was confirmed to be malignant peripheral nerve sheath tumor on the basis of immunopositivity for vimentin, neurone specific enolase and S-100.</p> <p>Conclusion</p> <p>To the best of our knowledge only six such case reports have been published in literature. The differential diagnosis of malignant peripheral nerve sheath tumor should be considered by the clinician as well as the pathologists in the work-up of a breast neoplasm as treatment and prognosis of this rare malignancy is different.</p

Malignant neuroectodermal tumor with melanocytic and rhabdomyoblastic differentiation

Malignant melanoma can metastasize widely and vary significantly in its histological appearance; it rarely presents as a deep-seated mass without an obvious primary site elsewhere. Malignant peripheral nerve sheath tumor (MPNST) is a high-grade sarcoma characterized by conventional and epithelioid subtypes. MPNST can demonstrate heterologous differentiation, usually in the form of osteosarcomatous, chondrosarcomatous, or rhabdomyosarcomatous differentiation. MPNST does not harbor true melanocytic differentiation, although epithelioid MPNST typically is diffusely S-100 protein positive and superficially can resemble malignant melanoma. An unusual intra-abdominal mass was recently encountered with features of both melanoma and conventional or epithelioid MPNST containing a fascicular spindle cell component, an epithelioid component with melanocytic differentiation, as well as a rhabdomyosarcomatous component. The terminology “malignant neuroectodermal tumor with melanocytic and rhabdomyoblastic differentiation” is proposed to describe this neoplasm, reflecting the unusual concomittant lines of differentiation as well as offering a possible rationale for nosologically challenging aspects of this neoplasm

Brain metastases as primary manifestation of a melanocytic malignant peripheral nerve sheath tumor in a 60-year-old man

BACKGROUND: Malignant peripheral nerve sheath tumors are rare tumor entities that originate from peripheral nerve sheaths and have an unfavorable prognosis. Metastatic spread to the cerebral parenchyma is absolutely rare. This case report describes the clinical course in a 60-year-old man whose tumor came to medical attention because of a seizure. CASE PRESENTATION: Magnetic resonance imaging demonstrated two intracerebral lesions. The symptomatic lesion was removed microneurosurgically and histology demonstrated a metastasis from a malignant peripheral nerve sheath tumor. Postoperatively, whole-brain irradiation was performed. The primary tumor was identified in the area of the sciatic nerve on the right. Follow-up 14 months after resection showed that there was no progression of the intracerebral lesions but an increase in size and number of distant metastases. CONCLUSION: There are no generally accepted guidelines for the treatment of malignant peripheral nerve sheath tumors with cerebral metastases. This case report presents and discusses one possible therapeutic approach. Due to the poor overall prognosis, the least invasive therapy should be chosen