title: Mastoid recurrence after radiotherapy for nasopharyngeal carcinoma: two case studies.
abstract: BACKGROUND
  The mastoid is a rare site of nasopharyngeal carcinoma recurrence after radiotherapy, and no relevant reports are currently in the literature.
  
  
  METHODS
  Two case reports are presented describing patients with a history of nasopharyngeal carcinoma who received primary radical radiotherapy. The first was treated by conventional radiotherapy, using 2-dimensional techniques, while the second was delivered by intensity-modulated radiation therapy (IMRT).
  
  
  RESULTS
  The patients presented with progressive mastoid recurrence after radiotherapy at 12 and 16 months, respectively. Clinical presentation of mastoid recurrence was similar to mastoiditis. Meanwhile, distant metastasis occurred in both cases. To date, 1 has died of distant metastasis, and the other is alive with disease stabilization following chemotherapy treatment.
  
  
  CONCLUSIONS
  This is the first report of mastoid recurrence after radiotherapy for nasopharyngeal carcinoma, which should alert clinicians to probe into the pathogenesis and pay attention to the relationship between mastoid recurrence and distant metastasis.
authors.affiliation: Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
authors.forename: Ximei
authors.initials: X
authors.lastname: Zhang
authors.forename: Jingwei
authors.initials: J
authors.lastname: Luo
authors.forename: Li
authors.initials: L
authors.lastname: Gao
authors.forename: Guozhen
authors.initials: G
authors.lastname: Xu
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002277:Carcinoma / Q000473:pathology / Q000532:radiotherapy / Q000556:secondary; D002945:Cisplatin / Q000008:administration & dosage; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008297:Male; D008416:Mastoid / Q000473:pathology*; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local; D050397:Radiotherapy, Intensity-Modulated; D012888:Skull Neoplasms / Q000556:secondary* / Q000628:therapy; D014747:Vinblastine / Q000008:administration & dosage / Q000031:analogs & derivatives; D000077235:Vinorelbine
chemical_list: D014747:Vinblastine; D002945:Cisplatin; D000077235:Vinorelbine