Pulmonary Ewing Sarcoma/Primitive Neuroectodermal Tumor: A Case Report and a Review of the Literature

Primary bronchial Ewing sarcoma

INTRODUCTION

Primary bronchial Ewing sarcoma (ES) is a rare endobronchial tumor.

PRESENTATION OF CASE

A 65-year-old male presented with six-month history of progressive shortness of breath. Flexible bronchoscopy showed an endobronchial polypoid tumor in the left main stem bronchus about 2 cm from the carina. The tumor was resected by a left bronchial sleeve resection using a right postero-lateral thoracotomy approach. Pathology showed complete tumor resection with negative margins. The morphological and immune-phenotypical features of the resected specimen were compatible with ES. He had an uneventful post-operative recovery. He did not receive adjuvant radiation or chemotherapy and remains disease free at 9 months follow up.

DISCUSSION

A review of the literature identified six other cases of primary bronchial ES. In addition, there were three reported cases of primary ES involving the trachea and thirteen involving the lung parenchyma. Bronchial ES appeared to have a relatively better prognosis than ES involving the trachea or the lung. Our case demonstrates that primary bronchial ES may be treated safely with limited resection, lung preservation and without the need for adjuvant therapy if negative margins can be achieved.

CONCLUSION

Sleeve resection without adjuvant therapy may be a safe treatment option for primary bronchial ES.

Primary extraosseous Ewing sarcoma of the lung: Case report and literature review

Ewing sarcoma is the second most common primary osseous malignancy in children and young adults. However, infrequently, it can arise outside the skeletal system; rarer still, it can originate within the lung parenchyma. In this case report, we describe such a case in a 23-year-old male. We also review the literature to summarize imaging findings for this rare malignancy.

Primary Multiple Pulmonary Primitive Neuroectodermal Tumor: Case Report and Literature Review

Primitive neuroectodermal tumors (PNETs) arising directly from the lung are extremely rare but particularly aggressive neoplasms. Although thoracic PNET usually develops on the chest wall, there have been reports of primary Ewing sarcoma/PNET of the lung.We present the case of a 16-year-old male with PNET diagnosed following histologic and immunohistochemical examination of a video-assisted thoracic surgical biopsy. As typically occurring for these tumors, the diagnosis was initially delayed in our patient and prognosis was poor despite aggressive surgical resection and postoperative chemotherapy. We attempted to explore the use of targeted pharmacotherapy through high-throughput sequencing in this case. We found that this treatment using Avastin and Cetuximab could provide a new therapeutic direction for PNET.PNENTs arising from the lung parenchyma without pleural or chest wall involvement are extremely rare. Although uncommon, if the pathological features are similar to Ewing sarcoma, PNENTs should be kept in mind, and the target therapy may be a potent treatment for this disease.

PNET with neuroendocrine differentiation of the lung: Report of an unusual entity

Ewing's sarcoma/primitive neuroectodermal tumor (PNET) has been the subject of recent reports describing morphologic variants (adamantinoma-like, large cell, spindle cell, sclerosing, clear cell, and vascular-like) of the most classic form, as well as cases displaying unusual morphologic differentiation and atypical immunohistochemical features. We report a case of an uncommon lung tumor in a 20-year-old female, morphologically and molecularly consistent with an Ewing's sarcoma/PNET tumor with foci of squamous differentiation, and peculiar expression of vimentin, high-molecular-weight keratins, p63, synaptophysin, and chromogranin. This case raises a challenging differential diagnostic problem with therapeutic implications: Should the patient be treated following the protocols for Ewing's sarcoma/PNET tumors or as for lung carcinoma with neuroendocrine features? The patient we report here was treated with neoadjuvant chemotherapy for Ewing's sarcoma/PNET according to Euro Ewing 99 study protocol followed by surgery and has no evidence of disease 15 months after the initial diagnosis. This highlights the importance of achieving the correct diagnosis of these atypical tumors using all clinical, morphological, and ancillary methods available to allow for their correct and timely treatment.