title: Predictors of response to radio-embolization (TheraSphere®) treatment of neuroendocrine liver metastasis.
abstract: BACKGROUND
  Neuroendocrine tumours (NET) frequently metastasize to the liver. NET liver metastasis has been shown to respond to Yttrium-90 microspheres therapy. The aims of the present study were to define factors that predict the response to radio-embolization in patients with NET liver metastases.
  
  
  METHODS
  From January 2006 until March 2009, all patients with NET liver metastasis that received radio-embolization using TheraSphere® (glass microspheres) were reviewed. The response was determined by a change in the percentage of necrosis (ΔN%) after the first radio-embolization based on the modified RECIST criteria (mRECIST) criteria. The following confounding variables were measured: age, gender, size of the lesions, liver involvement, World Health Organization (WHO) classification, the presence of extra-hepatic metastasis, octereotide treatment and previous operative [surgery and (RFA)] and non-operative treatments (chemo-embolization and bland-embolization).
  
  
  RESULTS
  In all, 25 patients were identified, with a median follow-up of 21.7 months. The median age was 64.6 years, 28% had extra-hepatic metastasis and 56% were WHO stage 2. Post-treatment, the mean ΔN% was 48.4%. Previous surgical therapy was a significant predictor of the response with a response rate of 66.7 ΔN% vs. 31.5 ΔN% (P= 0.02). Bilateral liver disease, a high percentage of liver involvement and large metastatic lesions were inversely related to the degree of tumour response although did not reach statistical significance.
  
  
  CONCLUSIONS
  Radio-embolization increased the necrosis of NET liver metastasis mainly in patients with less bulky disease. This may imply that surgical therapy before radio-embolization would increase the response rates.
authors.affiliation: Section of HPB and Transplant Surgery, McGill University Health Center, Montreal, Canada. mohammedfsh@yahoo.com
authors.forename: Mohammed
authors.initials: M
authors.lastname: Shaheen
authors.forename: Mazen
authors.initials: M
authors.lastname: Hassanain
authors.forename: Murad
authors.initials: M
authors.lastname: Aljiffry
authors.forename: Tatiana
authors.initials: T
authors.lastname: Cabrera
authors.forename: Prosanto
authors.initials: P
authors.lastname: Chaudhury
authors.forename: Eve
authors.initials: E
authors.lastname: Simoneau
authors.forename: Nuttawut
authors.initials: N
authors.lastname: Kongkaewpaisarn
authors.forename: Ayat
authors.initials: A
authors.lastname: Salman
authors.forename: Juan
authors.initials: J
authors.lastname: Rivera
authors.forename: Mohammad
authors.initials: M
authors.lastname: Jamal
authors.forename: Robert
authors.initials: R
authors.lastname: Lisbona
authors.forename: Azzam
authors.initials: A
authors.lastname: Khankan
authors.forename: David
authors.initials: D
authors.lastname: Valenti
authors.forename: Peter
authors.initials: P
authors.lastname: Metrakos
mesh_terms: D000368:Aged; D004621:Embolization, Therapeutic; D005260:Female; D005500:Follow-Up Studies; D006499:Hepatic Artery; D006801:Humans; D007269:Injections, Intra-Arterial; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary / Q000628:therapy*; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000175:diagnosis / Q000556:secondary / Q000628:therapy*; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D015021:Yttrium Radioisotopes / Q000008:administration & dosage*
chemical_list: D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes