{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T02:14:42Z","timestamp":1793499282308,"version":"4.5.0"},"reference-count":44,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"3","license":[{"start":{"date-parts":[[2020,4,8]],"date-time":"2020-04-08T00:00:00Z","timestamp":1586304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Neurosurg.","NEUROS"],"published-print":{"date-parts":[[2020,9]]},"abstract":"Abstract<\/jats:title>\n \n BACKGROUND<\/jats:title>\n Stereotactic radiosurgery (SRS) is a safe and effective treatment for acromegaly.<\/jats:p>\n <\/jats:sec>\n \n OBJECTIVE<\/jats:title>\n To improve understanding of clinical and dosimetric factors predicting biochemical remission.<\/jats:p>\n <\/jats:sec>\n \n METHODS<\/jats:title>\n \n A single-institution cohort study of nonsyndromic, radiation-na\u00efve patients with growth hormone-producing pituitary adenomas (GHA) having single-fraction SRS between 1990 and 2017. Exclusions were treatment with pituitary suppressive medications at the time of SRS, or <24 mo of follow-up. The primary outcome was biochemical remission\u2014defined as normalization of insulin-like growth factor-1 index (IGF-1\n i<\/jats:italic>\n ) off suppression. Biochemical remission was assessed using Cox proportional hazards. Prior studies reporting IGF-1\n i<\/jats:italic>\n were assessed via systematic literature review and meta-analysis using random-effect modeling.\n <\/jats:p>\n <\/jats:sec>\n \n RESULTS<\/jats:title>\n \n A total of 102 patients met study criteria. Of these, 46 patients (45%) were female. The median age was 49 yr (interquartile range [IQR]\u00a0=\u00a037-59), and the median follow-up was 63 mo (IQR\u00a0=\u00a029-100). The median pre-SRS IGF-1\n i<\/jats:italic>\n was 1.66 (IQR\u00a0=\u00a01.37-3.22). The median margin dose was 25 Gy (IQR\u00a0=\u00a021-25); the median estimated biologically effective dose (BED) was 169.49 Gy (IQR\u00a0=\u00a0124.95-196.00). Biochemical remission was achieved in 58 patients (57%), whereas 22 patients (22%) had medication-controlled disease. Pre-SRS IGF-1\n i<\/jats:italic>\n \u00a0\u2265\u00a02.25 was the strongest predictor of treatment failure, with an unadjusted hazard ratio (HR) of 0.51 (95% CI\u00a0=\u00a00.26-0.91,\n P<\/jats:italic>\n \u00a0=\u00a0.02). Number of isocenters, margin dose, and BED predicted remission on univariate analysis, but after adjusting for sex and baseline IGF-1\n i<\/jats:italic>\n , only BED remained significant\u2014and was independently associated with outcome in continuous (HR\u00a0=\u00a01.01, 95% CI\u00a0=\u00a01.00-1.01,\n P<\/jats:italic>\n \u00a0=\u00a0.02) and binary models (HR\u00a0=\u00a02.27, 95% CI\u00a0=\u00a01.39-5.22,\n P<\/jats:italic>\n \u00a0=\u00a0.002). A total of 24 patients (29%) developed new post-SRS hypopituitarism. Pooled HR for biochemical remission given subthreshold IGF-1\n i<\/jats:italic>\n was 2.25 (95% CI\u00a0=\u00a01.33-3.16,\n P<\/jats:italic>\n \u00a0<\u00a0.0001).\n <\/jats:p>\n <\/jats:sec>\n \n CONCLUSION<\/jats:title>\n \n IGF-1\n i<\/jats:italic>\n is a reliable predictor of biochemical remission after SRS. BED appears to predict biochemical outcome more reliably than radiation dose, but confirmatory study is needed.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1093\/neuros\/nyaa054","type":"journal-article","created":{"date-parts":[[2020,2,13]],"date-time":"2020-02-13T15:11:16Z","timestamp":1581606676000},"page":"538-546","source":"Crossref","is-referenced-by-count":47,"title":["The Impact of Insulin-Like Growth Factor Index and Biologically Effective Dose on Outcomes After Stereotactic Radiosurgery for Acromegaly: Cohort Study"],"prefix":"10.1227","volume":"87","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5314-1067","authenticated-orcid":false,"given":"Christopher S","family":"Graffeo","sequence":"first","affiliation":[{"name":"Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diane","family":"Donegan","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, Indiana University, Indianapolis, Indiana"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dana","family":"Erickson","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul D","family":"Brown","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0231-7346","authenticated-orcid":false,"given":"Avital","family":"Perry","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael J","family":"Link","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota"},{"name":"Department of Otorhinolaryngology, MayoClinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William F","family":"Young","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruce E","family":"Pollock","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota"},{"name":"Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2020,9]]},"reference":[{"key":"bib1-20231011","doi-asserted-by":"crossref","first-page":"386401","DOI":"10.1155\/2012\/386401","article-title":"Surgery and radiosurgery for acromegaly: a review of indications, operative techniques, outcomes, and complications","volume":"2012","author":"Marquez","year":"2012","journal-title":"Int J 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