title: Thyroid lobe ablation with radioactive iodine as an alternative to completion thyroidectomy after hemithyroidectomy in patients with follicular thyroid carcinoma: long-term follow-up.
abstract: BACKGROUND
  Radioactive iodine lobe ablation (RAI-L-ABL) is a possible alternative to completion thyroidectomy (C-Tx) for follicular thyroid carcinoma (FTC), but no long-term outcome data are available after lobe ablation. We analyzed the long-term outcome of lobe ablation in a series of patients with FTC.
  
  
  METHODS
  This was a retrospective study of patients who were treated with lobe ablation between 1983 and 2008. Of 134 patients with FTC, 37 (27.6%) had lobe ablation with (131)I (30-32 mCi) (RAI-L-ABL), 68 (50.7%) had C-Tx, and 29 (21.6%) had initial total thyroidectomy (T-Tx). The main outcomes analyzed were (131)I uptake after lobe ablation, C-Tx or T-Tx, serum thyroglobulin (Tg), serum thyroid-stimulating hormone (TSH), long-term disease-specific mortality, and disease-free survival.
  
  
  RESULTS
  After lobe ablation, radioiodine uptake was significantly lower for the RAI-L-ABL group (0.6%) than for the C-Tx group (2.0%, p<0.005) or T-Tx group (1.3%, p=0.054). Subsequent remnant ablation was performed in 12 of 37 (32%) patients in the RAI-L-ABL group, in 58 of 68 (85.3%) patients in the C-Tx group, and in 25 of 29 (86.2%) patients in the T-Tx group (p<0.01). With median follow-up of 95 months for the RAI-L-ABL group, 47 months for the C-Tx group, and 53 months for the T-Tx group, there was one death in the RAI-L-ABL group and one death in the T-Tx group. No other RAI-L-ABL patients had detectable disease, whereas patients in the C-Tx group and two patients in the T-Tx group had detectable disease (p=0.18). Long-term stimulated or suppressed Tg of <1 ng/mL were found in 87.5% of the RAI-L-ABL group (n=28), 86.3% of the C-Tx group (n=57), and 77.8% of the T-Tx group (n=21). Tg was detectable in 40.6% of the RAI-L-ABL group compared to 13.8% of C-Tx and 28.6% of T-Tx groups (p<0.05, between groups).
  
  
  CONCLUSIONS
  RAI-L-ABL, C-Tx, and T-Tx are equally effective in achieving serum TSH concentrations of >25 mIU/L and preparing patients for conventional (131)I treatment and whole body scanning with similar long-term outcomes. However, persistent measurable Tg (range 0.2-2.2 ng/mL) is more common after RAI-L-ABL.
authors.affiliation: Thyroid Unit, Massachusetts General Hospital, Boston, Massachusetts 02114, USA. gbarbesino@partners.org
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Barbesino
authors.forename: Melanie
authors.initials: M
authors.lastname: Goldfarb
authors.forename: Sareh
authors.initials: S
authors.lastname: Parangi
authors.forename: Jingyun
authors.initials: J
authors.lastname: Yang
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Ross
authors.forename: Gilbert H
authors.initials: GH
authors.lastname: Daniels
mesh_terms: D000328:Adult; D000368:Aged; D018265:Carcinoma, Papillary, Follicular / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D013954:Thyroglobulin / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D013965:Thyroidectomy / Q000009:adverse effects; D013972:Thyrotropin / Q000378:metabolism; D016896:Treatment Outcome
chemical_list: D007457:Iodine Radioisotopes; D013972:Thyrotropin; D013954:Thyroglobulin