Baba et al. Journal of Medical Case Reports 2011, 5:25 http://www.jmedicalcasereports.com/content/5/1/25 easily mistaken for tumor recurrence. The enhanced lesions were likely viable infectious cells, consistent with the effectiveness of the antibiotics, whereas the non- enhanced lesions were likely necrotic cells. In addition to the similarity of clinical conditions and CT findings in patients with radionecrosis and recurrent lesions, some submucosal recurrent lesions may not be detected by biopsy under direct laryngoscopy, especially in patients with significant mucosal edema. Moreover, in some patients, radionecrosis and recurrent tumor may occur concurrently. Thus, differential diagnosis between radionecrosis and tumor recurrence is consid- ered extremely difficult. Positron emission tomography- (PET)-CT is an alternative imaging modality that has been successfully used to differentiate postradiation changes, radionecrosis, and tumor recurrence. Further- more, Fludeoxyglucose- (FDG)-PET scanning after radiation can predict tumor regrowth three months later [12]. However, follow-up PET-CT in our patient after therapy yielded negative results (data not shown). Patients with T3/T4 hypopharyngeal SCC usually require total laryngopharyngectomy. Because our patient initially had bulky stage IV disease, associated with frank thyroid cartilage invasion, total laryngopharyngectomy was applicable. However, the patient desired organ pre- servation and therefore chose chemoradiotherapy as an alternative to total laryngopharyngectomy [5]. As a result, the patient retained appreciable vocal cord function of speech and deglutition, and his prognosis was good at two years after primary radiotherapy without tumor recurrence. The return of vocal cord function after che- moradiotherapy is a useful prognostic factor, with a five- year overall survival rate in patients with recovered vocal cord function of 100%, compared with a two-year overall survival rate of patients with vocal cord fixation of less than 40% [13]. Our patient recovered vocal cord fixation, with no obvious signs of tumor recurrence more than two years after initial chemoradiotherapy. Therefore, che- moradiotherapy was appropriate for this patient. Conclusions A patient developed a condition after chemoradiother- apy for hypopharyngeal cancer that required differential diagnosis between radionecrosis and tumor recurrence. Our findings emphasize the wide spectrum of radio- graphic presentation of radionecrosis. Consent Written informed consent was obtained from the patient for publication of this case report and any accompany- ing images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. 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