Abstract
Spontaneous pneumomediastinum is conventionally defined as a disease that does not result from trauma or underlying disease. In recent years, many patients have had some kind of triggering factor, such as sports or a strong cough. Herein, we report a case of mediastinal emphysema with a parapharyngeal tumor at the time of initial examination. Although the patient was referred to our hospital on suspicion of cervical abscess such as descending necrotizing mediastinitis by symptoms, it seemed that the cause was a spontaneous pneumomediastinum associated with a parapharyngeal tumor coincidentally. The pneumomediastinum resolved day by day, and the parapharyngeal tumor was extracted without recurrence, which turned out to be a pleomorphic adenoma. As far as we are concerned, there have been no reports of spontaneous pneumomediastinum associated with a parapharyngeal space tumor.