A 15 year-old adolescent was referred with 2 month history of worsening of breathlessness and haemoptysis. He also reported constitutional symptoms of fever, poor appetite and weight loss. The chest roentgenogram showed a massive right pleural effusion with apparent cardiomegaly. The cardiac silhouette over the right heart border was obliterated and the mediastinum was widened. Computed tomogram of the thorax showed a bulky heterogeneous mass in the right lung with extension to the heart. Subsequent CT guided lung biopsy revealed Primitive Neuroectodermal tumour (PNET). Here, we illustrate the clinical course of an aggressive pulmonary PNET with lethal cardiac metastasis.
Ewing sarcoma (ES)/ primitive neuroectodermal tumour (PNET) is an aggressive malignant neoplasm affecting mainly children and young adults. The tumour is included with other primitive neoplasms under the category of small round cell tumour. Cytokeratin expression in ES/PNET has been described in sporadic case reports as well as a few systemic series. We studied this feature in Malaysian patients diagnosed in University Malaya Medical Centre on the basis of typical morphology and immunohistochemical assays. Immunohistochemical staining for AE1/AE3 and MNF116 were performed in 43 cases. Cytokeratin was expressed in 17 cases (39.5%) in focal, intermediate or diffuse patterns. There was no significant association between cytokeratin immunoreactivity and the following parameters: patient age, sex, skeletal and extraskeletal primary location as well as primary, metastastic or recurrent tumours or chemotherapy treatment. A significant association between cytokeratin and neuron specific enolase (NSE) expression was demonstrated. Our study supports evidence of epithelial differentiation in ES/PNET and emphasizes that the expression of cytokeratin does not exclude ES/PNET in the differential diagnosis of small round cell tumours.
Primary primitive neuroectodermal tumour (PNET) and extraskeletal Ewing's sarcoma belongs to the Ewing's family of tumours. Primary tumours arising from breast are very rare. There are only a few case reports published on primary extraskeletal Ewing's sarcoma and PNET arising from breast. We present an extremely rare case of an inoperable primary Ewing's sarcoma arising from left breast with contralateral breast, lymphatic and lung metastasis.