title: Should patients with remnants from thyroid microcarcinoma really not be treated with iodine-131 ablation?
abstract: Remnant ablation by radioiodine is generally not recommended in patients presenting uni- or multifocal cancer <1 cm, in the absence of other higher risk features. We retrospectively studied low-risk patients (pts) with differentiated thyroid cancer (DTC) less than 1 cm recruited for radioiodine therapy (RAI).
  
  
  METHODS
  91 pts (79 women, age 48.4 ± 12 yrs) with DTC were enrolled for RAI. Patients underwent pre-therapy ultrasonography (US), those with suspected/ambiguous lymph-nodes were excluded and proposed for cytology. Treated pts underwent post-therapeutic whole body scan (WBSt) completed by neck/chest SPECT/CT, when necessary (e.g. evidence of uptake outside of thyroid bed). A target lesion on SPECT/CT was defined as an identifiable lymph-nodal site presenting a matched significant iodine uptake. The patients were followed up for 14 ± 2 months thereafter.
  
  
  RESULTS
  All pts/cancers were pT1. The mean histological diameter was 0.68 ± 0.23 cm. Six patients were excluded because of suspected nodal involvement at US. Thirty (35 %) out of 85 pts had suspicious WBSt as per lymph-nodal involvement which was confirmed at the subsequent SPECT/CT acquisition in most part of pts (26/30; 86 %). Overall detected target lesions was 34, and nine (26 %) had interim positive fine needle cytology.
  
  
  CONCLUSIONS
  a significant part of low risk DTC patients, for whom RAI is not recommended, presents an incidental suspicion of lymph-nodal involvement at WBSt confirmed by subsequent SPECT/CT. Such setting would have not been treated by I-131.
authors.affiliation: Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Centro di Riferimento Oncologico di Basilicata (CROB), Via P. Pio 1, 85028, Rionero in Vulture, Italy.
authors.forename: Rosj
authors.initials: R
authors.lastname: Gallicchio
authors.forename: Sabrina
authors.initials: S
authors.lastname: Giacomobono
authors.forename: Daniela
authors.initials: D
authors.lastname: Capacchione
authors.forename: Anna
authors.initials: A
authors.lastname: Nardelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Barbato
authors.forename: Antonio
authors.initials: A
authors.lastname: Nappi
authors.forename: Teresa
authors.initials: T
authors.lastname: Pellegrino
authors.forename: Giovanni
authors.initials: G
authors.lastname: Storto
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D013965:Thyroidectomy; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D047368:Tumor Burden; D051598:Whole Body Imaging
chemical_list: D007457:Iodine Radioisotopes
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