title: Retrospective analysis of long-term surgical results in acromegaly: preoperative and postoperative factors predicting outcome.
abstract: OBJECTIVE
  Sixty-one of 83 patients with acromegaly treated between 1969 and 1993 were analysed retrospectively to clarify which early postoperative factors were significant predictors of a successful long-term outcome and which preoperative factors significantly influenced the early postoperative results.
  
  
  METHODS
  Of the 61 patients, 30 were operated on before 1987 and 31 afterwards. A successful long-term surgical outcome was defined as a long-term mean basal GH level < 6 mU/l (comparable to < 3 micrograms/l), a normal IGF-I level, and normal GH dynamics.
  
  
  RESULTS
  Overall, 59% of patients (37% before 1987 and 81% after) had an early postoperative mean basal GH level < 6 mU/l, and 56% (29% before 1987 and 77% after) met all three of the specified criteria for a successful long-term surgical outcome. Statistical analysis confirmed that GH dynamics and postoperative mean basal GH level < 6 mU/l were significant predictors of the long-term surgical outcome, whereas the postoperative IGF-I level alone was not. On the other hand, abnormal preoperative GH dynamics were normalized in all patients with a postoperative mean basal level < 6 mU/l. In addition, there were no patients showing an unsuccessful long-term outcome in those associated with both the early postoperative mean basal GH level < 6 mU/l and normalization of the IGF-I level. Therefore, measurement of the early postoperative mean basal GH level and the IGF-I level may be an economical and simple guide to predict the long-term surgical outcome. Moreover, multivariate analysis indicated that cavernous sinus invasion was an independent significant factor influencing the early postoperative outcome.
  
  
  CONCLUSIONS
  Successful long-term surgical outcome may be predicted if early postoperative mean basal GH level is reduced to < 6 mU/l (< 3 micrograms/l) and IGF-I level becomes normal. This study also confirms that early diagnosis and treatment by an experienced endocrinologist and neurosurgeon can improve the operative results in patients with acromegaly.
authors.affiliation: Department of Neurosurgery, Toranomon General Hospital, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamada
authors.forename: T
authors.initials: T
authors.lastname: Aiba
authors.forename: K
authors.initials: K
authors.lastname: Takada
authors.forename: Y
authors.initials: Y
authors.lastname: Ozawa
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
authors.forename: S
authors.initials: S
authors.lastname: Sawano
authors.forename: Y
authors.initials: Y
authors.lastname: Shishiba
authors.forename: T
authors.initials: T
authors.lastname: Sano
mesh_terms: D000172:Acromegaly / Q000097:blood / Q000378:metabolism / Q000601:surgery*; D000328:Adult; D005260:Female; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D015999:Multivariate Analysis; D011184:Postoperative Period; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone