[Peripheral primitive neuroectodermal tumor of trachea: a case report and review of literatures]

To improve the understanding of tracheal peripheral primitive neuroectodermal tumor (PNET).

A case of tracheal PNET diagnosed in July 2010 was reported and the related literatures were reviewed. The literature review was carried out respectively with "primitive neuroectodermal tumor", "peripheral" as the search terms in Wanfang med online and PubMed database by September 2011.

A case of 63 year-old female patient, who had been misdiagnosed as having chronic pharyngitis, chronic bronchitis and bronchial asthma, was admitted to the hospital because of cough and sputum production for 50 days, and anhelation for 1 month. After admission, the chest computerized tomography showed a space-occupying lesion in the middle of the trachea. Bronchoscopy showed a pedicle neoplasm 4 cm under the subglottic, with integral capsule, smooth surface and rich vascellum. Subsequently, tumor resection under bronchoscope was performed. Pathology report after operation showed infiltration of flake small round malignant cells under bronchial mucosa. Immunohistochemistry showed CD(99)(+), Syn(+) and S-100(+). EWS-FLI-1 fusion transcript was detected by RT-PCR. Accordingly, it was diagnosed as PNET. The symptoms of cough and anhelation were disappeared after operation. So far, there was no local recurrence and distant metastasis with 14 months follow-up. A total of 111 literatures were received in Pubmed, including one of prospective study, one of review, 22 of retrospective study and 87 of case report. Forty literatures and 187 cases in all were received in Wanfang Med Online, including 24 of retrospective study and 16 of case report. But, there were no reports about tracheal PNET.

PNET can occur in the trachea and is easy to be misdiagnosed. To make a definite diagnosis, histopathology and immunohistochemistry are needed and detection of EWS-FLI-1 fusion transcript is a reliable marker for molecular diagnosis. The tracheal pPNET may be different with the pPNETs in other parts, and has a lower-grade invasion and less distant metastasis.