A 24 year old woman with bilateral oral white patches was referred to dermatology clinic. Her chief complaint was mouth burning. Pathological report of cut section biopsy from oral mucosa was in favor of lichen planus. Intralesional corticosteroid injection and it's subsequent systemic administration 30 mg/ daily for one month showed no improvement. Therefore a combination of systemic corticosteroid and topical mucosal triamcinolon- actinide in orabase gel( kenalog in orabase) was used. In next examination , two weeks later, mucosal lesions showed improvement, but she was suffering from dyspnea following withdrawal of corticosteroid. One month later she was referred to emergency medical center of a general hospital due to acute respiratory dyspnea. Broncoscopic examination revealed intratracheal mass with nearly complete tracheal obstruction. Microscopic pathological findings of needle biopsy, showed unclassified carcinoma. Tumor was not operatable so radio- chemotherapy was started. The patient had been followed up during last two years with no clinical problem.