title: High-risk patients with differentiated thyroid cancer T4 primary tumors achieve remnant ablation equally well using rhTSH or thyroid hormone withdrawal.
abstract: BACKGROUND
  Few data exist on using thyrotropin alfa (recombinant human thyroid-stimulating hormone [rhTSH]) with radioiodine for thyroid remnant ablation of patients who have T4 primary tumors (invasion beyond the thyroid capsule).
  
  
  METHODS
  A retrospective chart review protocol at nine centers in Europe was set up with special waiver of need for informed consent, along with a careful procedure to avoid selection bias when enrolling patients into the database. Data on 144 eligible patients with T4 tumors were collected (T4, N0-1, M0-1; mean age 49.7 years; 65% female; 88% papillary cancer). All had received (131)I remnant ablation following TSH stimulation with rhTSH or thyroid hormone withdrawal (THW) since January 2000 (rhTSH n=74, THW n=70). The primary endpoint was based on evaluation of diagnostic radioiodine scan thyroid bed uptake more than six months after the ablation procedure, while stimulated serum Tg was a secondary endpoint. Safety was evaluated within 30 days after rhTSH or (131)I.
  
  
  RESULTS
  Successful ablation judged by scan was achieved in 65/70 (92.9%) of rhTSH and in 61/67 (91.0%) of THW patients; the success rates were comparable, since noninferiority criteria were met. Although some patients in the initial cohort had tumor in cervical nodes and metastases, considering all evaluable patients regardless of various serum anti-Tg antibody assessments, the stimulated Tg was <2 ng/mL in 48/70 (68.6%) and 39/67 (58.2%) in rhTSH and THW groups respectively; if patients with anti-Tg antibody levels >30 IU/mL were excluded, the stimulated Tg was <2 ng/mL in 42/62 (67.7%) and 37/64 (57.8%) respectively. No serious adverse events occurred within the 30-day window after ablation.
  
  
  CONCLUSIONS
  Use of rhTSH as preparation for thyroid remnant ablation in patients with T4 primary tumors achieved a rate of ablation success that was high and noninferior to the rate seen after THW, and rhTSH was well tolerated.
authors.affiliation: 1 Department of Nuclear Medicine, University of Munich , Munich, Germany .
authors.forename: Peter
authors.initials: P
authors.lastname: Bartenstein
authors.forename: Elisa Caballero
authors.initials: EC
authors.lastname: Calabuig
authors.forename: Carlo Ludovico
authors.initials: CL
authors.lastname: Maini
authors.forename: Renzo
authors.initials: R
authors.lastname: Mazzarotto
authors.forename: M Angustias
authors.initials: MA
authors.lastname: Muros de Fuentes
authors.forename: Thorsten
authors.initials: T
authors.lastname: Petrich
authors.forename: Fernando José Cravo
authors.initials: FJ
authors.lastname: Rodrigues
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Vallejo Casas
authors.forename: Federica
authors.initials: F
authors.lastname: Vianello
authors.forename: Michela
authors.initials: M
authors.lastname: Basso
authors.forename: Marcelino Gómez
authors.initials: MG
authors.lastname: Balaguer
authors.forename: Alexander
authors.initials: A
authors.lastname: Haug
authors.forename: Fabio
authors.initials: F
authors.lastname: Monari
authors.forename: Raquel Sánchez
authors.initials: RS
authors.lastname: Vaňó
authors.forename: Rosa
authors.initials: R
authors.lastname: Sciuto
authors.forename: James
authors.initials: J
authors.lastname: Magner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000188:drug therapy* / Q000532:radiotherapy; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy / Q000601:surgery; D013965:Thyroidectomy; D057073:Thyrotropin Alfa / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007457:Iodine Radioisotopes; D057073:Thyrotropin Alfa