Intensity-modulated radiotherapy for localized nasopharyngeal amyloidosis. Case report and literature review

Primary localized amyloidosis is characterized by the deposition of amyloid proteins restricted to one organ, without systemic involvement. Primary nasopharyngeal amyloidosis is an exceedingly rare condition, for which the standard treatment remains unknown. Because of its challenging anatomical position, surgery alone hardly results in complete resection of the localized amyloidosis. Therefore, an interdisciplinary planning board to design optimal treatment is of particular importance. A 39-year-old man presented with a several-week history of nasal obstruction and epistaxis. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed the presence of a retro-odontoid nonenhancing soft tissue mass. The endoscopic biopsy demonstrated that the mass was amyloid in nature. An extensive systemic workup revealed an absence of inflammatory process, systemic amyloidosis, or plasma cell dyscrasia. The patient was treated with a combination of surgery and radiotherapy, showing no evidence of recurrence or progression at his 1-year follow-up. Primary solitary amyloidosis is a rare form of amyloidosis. To the best of our knowledge, this is the first report of a nasopharyngeal amyloidosis case treated with excision and radiation leading to complete remission. Because of the difficulty for surgeons to achieve radical resection with such lesions, radiotherapy proved to be an excellent adjuvant treatment in this case. (orig.)