title: Prognostic significance of the Ki-67 labeling index in growth hormone-secreting pituitary adenomas.
abstract: BACKGROUND
  Ki-67 is a marker of proliferation activity associated with invasiveness and prognosis in human tumors.
  
  
  OBJECTIVE
  The aim of the study was to evaluate the Ki-67 index prognostic relevance in a group of acromegalic patients who underwent transsphenoidal surgery for a GH-secreting pituitary adenoma.
  
  
  METHODS
  We selected 68 consecutive acromegalic patients referred to our hospital during a 5-yr period. The Ki-67 index was determined by immunohistochemistry on tissue samples obtained from each adenoma after surgery. Those patients who were not completely cured after surgery began medical therapy with somatostatin analogs (SSAs). Periodical pituitary magnetic resonance imaging and hormonal evaluation were performed during the follow-up.
  
  
  RESULTS
  Twenty-eight of 68 patients were cured after surgery (41%). Among the 40 patients treated with SSAs, 13 were considered uncontrolled. Pituitary magnetic resonance imaging showed residual/recurrent disease in 25 of 68 patients after 6 months. No correlation was found between Ki-67 index and age, tumor size, GH, or IGF-I plasma levels. Tumors described as having cavernous sinus invasion had a higher mean Ki-67 index as compared with noninvasive tumors (P < 0.01). The Ki-67 index was significantly lower in tumors in patients cured after surgery as compared with patients considered not cured (P < 0.01) and in tumors in patients controlled by SSA therapy as compared with patients considered as uncontrolled (P < 0.05).
  
  
  CONCLUSIONS
  The Ki-67 labeling index may predict clinical outcome in postsurgical management of acromegalic patients. We suggest routine Ki-67 evaluation in GH-secreting pituitary adenomas.
authors.affiliation: Section of Endocrinology, Department of Internal Medicine, Università Cattolica del Sacro Cuore, Via Cassia 901, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Fusco
authors.forename: M C
authors.initials: MC
authors.lastname: Zatelli
authors.forename: A
authors.initials: A
authors.lastname: Bianchi
authors.forename: V
authors.initials: V
authors.lastname: Cimino
authors.forename: L
authors.initials: L
authors.lastname: Tilaro
authors.forename: F
authors.initials: F
authors.lastname: Veltri
authors.forename: F
authors.initials: F
authors.lastname: Angelini
authors.forename: L
authors.initials: L
authors.lastname: Lauriola
authors.forename: V
authors.initials: V
authors.lastname: Vellone
authors.forename: F
authors.initials: F
authors.lastname: Doglietto
authors.forename: M R
authors.initials: MR
authors.lastname: Ambrosio
authors.forename: G
authors.initials: G
authors.lastname: Maira
authors.forename: A
authors.initials: A
authors.lastname: Giustina
authors.forename: E C
authors.initials: EC
authors.lastname: degli Uberti
authors.forename: A
authors.initials: A
authors.lastname: Pontecorvi
authors.forename: L
authors.initials: L
authors.lastname: De Marinis
mesh_terms: D000236:Adenoma / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D000328:Adult; D000368:Aged; D005260:Female; D049912:Growth Hormone-Secreting Pituitary Adenoma / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013004:Somatostatin / Q000627:therapeutic use
chemical_list: D019394:Ki-67 Antigen; D013004:Somatostatin