Osteoradionecrosis of the temporal bone in nasopharyngeal carcinoma after radiotherapy: A case report.

Abstract

Osteoradionecrosis of the temporal bone after external-beam radiotherapy for nasopharyngeal carcinoma is not uncommon following a long posttreatment interval. We describe the case of a man who had experienced this complication 13 years after he had undergone such radiotherapy. His condition resolved after removal of dead bone from the external auditory canal, followed by antibiotic therapy and periodic aural toileting.

Case report

A 65-year-old Chinese man complained of a foul-smelling discharge from his right ear of 4 months' duration. His condition had been refractory to conservative treatment with topical antibiotics. He had undergone external-beam radiotherapy as a treatment for nasopharyngeal carcinoma (stage III, Ho's classification) 13 years earlier. The nasopharynx had received 60 Gy, and 42.5 Gy had been delivered to the neck.

An otoscopic examination of the right ear demonstrated an edematous external auditory canal, with an inflammatory polyp protruding from its superior wall (figure). A floating bone sequestrum was seen on the floor of the outer part of the external auditory canal and was undermined partly by skin. Histologic examination of the aural polyp revealed chronic inflammation, but no evidence of tumor recurrence. Computed tomography of the skull base, including the nasopharynx, did not suggest any recurrence or middle ear pathology except for erosion in the temporal bone that was compatible with osteoradio-necrosis. The ear discharge did not improve until the dead bone had been removed from the external auditory canal. Intermittent topical antibiotic treatment and regular aural toileting in clinic were prescribed.

Discussion

Osteoradionecrosis of the temporal bone following the treatment of nasopharyngeal carcinoma by external-beam radiotherapy is a complication not uncommonly seen following a long posttreatment interval--in this case 13 years. Ramsden et al classified osteoradionecrosis of the temporal bone as either local or diffuse.[1] The local type is characterized by the presence of a bone sequestrum that is confined to the external auditory canal. Patients usually present with chronic, offensive otorrhea and occasionally otalgia. In the diffuse type, a widespread ischemic osteonecrosis involves the skull base and adjacent structures. These patients have usually received higher doses of external irradiation to the temporal bone. Severe otalgia and pulsatile, offensive otorrhea are common. Cranial nerve palsies might also be present. Diffuse osteoradionecrosis is associated with a recognized incidence of local or regional complications, such as suppurative labyrinthitis, trismus, meningitis, cerebrospinal fluid leakage, and internal carotid aneurysm.[2]

The management of osteoradionecrosis in the temporal bone is controversial. Conservative treatment with frequent aural toileting and topical antibiotics is often administered for localized osteoradionecrosis.[1-3] Rudge described complete success with the use of hyperbaric oxygen therapy specifically for osteoradionecrosis of the temporal bone.[4] Other alternatives, such as modified radical mastoidectomy, have been performed in selected cases with good initial results,[5] but no long-term followup is available to validate this choice of treatment. Temporal bone resection for diffuse osteoradionecrosis is reported to be an effective treatment.[6-9]

From the Division of Otorhinolaryngology, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.

Reprint requests: Prof. Charles Andrew van Hasselt, Division of Otorhinolaryngology, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.

References

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(2.) John DG, Porter MJ, van Hasselt CA. Beware bleeding from the ear. J Laryngol Otol l993;107:137-9.

(3.) Sikand A, Longridge N. CSF otorrhea complicating osteoradionecrosis of the temporal bone. J Otolaryngol 1991;20: 209-11.

(4.) Rudge FW. Osteoradionecrosis of the temporal bone: Treatment with hyperbaric oxygen therapy. Mil Med 1993;158: 196-8.

(5.) Yuen PW, Wei WI. Tympanomastoidectomy for chronic suppurative otitis media of irradiated ears of nasopharyngeal carcinoma patients. J Otolaryngol 1994;23:302-4.

(6.) Ma KH, Fagan PA. Osteoradionecrosis of the temporal bone: A surgical technique of treatment. Laryngoscope 1988;98:554-6.

(7.) Thornley GD, Gullane PJ, Ruby RR, Heeneman H. Osteoradionecrosis of the temporal bone. J Otolaryngol 1979;8:396-400.

(8.) Guida RA, Finn DG, Buchalter IH, et al. Radiation injury to the temporal bone. Am J Otol 1990;11:6-11.

(9.) Kveton JF, Sotelo-Avila C. Osteoradionecrosis of the ossicular chain. Am J Otol 1986;7:446-8.