title: Long-term results of fractionated strontium-90 radiation therapy for pterygia.
abstract: OBJECTIVE
  The long-term safety and effectiveness of fractionated strontium-90 radiation therapy (RT) for pterygium were reviewed retrospectively.
  
  
  METHODS
  Between 1984 and 1996, 399 patients with 490 pterygia were treated with a strontium-90 eye applicator following surgical removal of the pterygium. The median follow-up period was 61 months (range 2-178). Of the 490 pterygia, 452 were fresh, 17 were recurrences after surgical removal alone, and 21 were recurrences after surgical removal plus postoperative RT. Fractionated RT of 31-42 Gy/4-5 fractions/22-29 days was given for 95.1% of the pterygia.
  
  
  RESULTS
  In total, 58 (11.8%) local recurrences of pterygia were noted. The median time of local recurrences was 10 months, ranging from 2 to 93 months, and 16 recurrences (28%) were noted later than 24 months after treatment. The interval between surgery and the start of RT (1-3 days vs. >3 days) and recurrent pterygia were significant variables for local control in the multivariate analysis, while total RT dose (7-29 Gy vs. 31-50 Gy) was a marginally significant variable. Late toxicities that may be associated with strontium-90 RT were scleromalacia (scleral thinning) in 4 eyes, adhesion of eyelids in 3 eyes, and scleral ulcer in 2 eyes.
  
  
  CONCLUSIONS
  Fractionated strontium-90 RT of approximately 40 Gy/4-5 fractions was safe and effective for preventing recurrence of pterygia, when RT was started within 3 days of surgery.
authors.affiliation: Department of Radiology, Kinki University School of Medicine, Osaka-Sayama, Japan. ynishi@med.kindai.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Nishimura
authors.forename: A
authors.initials: A
authors.lastname: Nakai
authors.forename: T
authors.initials: T
authors.lastname: Yoshimasu
authors.forename: Y
authors.initials: Y
authors.lastname: Yagyu
authors.forename: K
authors.initials: K
authors.lastname: Nakamatsu
authors.forename: H
authors.initials: H
authors.lastname: Shindo
authors.forename: O
authors.initials: O
authors.lastname: Ishida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011625:Pterygium / Q000532:radiotherapy* / Q000601:surgery; D012189:Retrospective Studies; D013326:Strontium Radioisotopes / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D013326:Strontium Radioisotopes