title: Is intraoperative calcitonin monitoring useful to modulate the extension of neck dissection in patients with medullary thyroid carcinoma?
abstract: BACKGROUND
  The extension of the compartment-oriented neck dissection at primary surgery in medullary thyroid carcinoma (MTC) is controversial. Because a <50 % decrease in intraoperative calcitonin levels (IO-CT) after total thyroidectomy plus central neck dissection (TT-CND) has been associated with residual disease, IO-CT monitoring has been proposed to predict the completeness of surgery. The goal of the present prospective study was to verify the accuracy of IO-CT monitoring.
  
  
  METHODS
  All patients scheduled for primary surgery for suspected or proven MTC between November 2010 and January 2013 were included. Calcitonin was measured pre-incision (basal level), after tumor manipulation, at the time TT-CND was accomplished (ablation level), 10 and 30 min after ablation. A decrease >50 % with respect to the highest IO-CT level 30 min after ablation was considered predictive of cure.
  
  
  RESULTS
  Twenty-six patients were included, and IO-CT monitoring identified 18 of 23 cured patients (true negative results) and 2 of 3 patients with persistent disease (true positive result). In 5 patients with normal basal and stimulated postoperative calcitonin levels, a decrease <50 % was observed (false positive results). In one of three patients with persistent disease a >50 % decrease in IO-CT was observed (false negative results). Specificity, sensitivity, and accuracy of IO-CT were 78.2, 66.6, and 76.9 %, respectively.
  
  
  CONCLUSIONS
  Intraoperative calcitonin monitoring is not highly accurate in predicting the completeness of surgical resection. In the present series, relying on IO-CT would result in limited resection in about one third of the patients with residual neck disease and in unnecessary lateral neck dissection in about 20 % of the cured patients.
authors.affiliation: Istituto di Semeiotica Chirurgica, U.O. Chirurgia Endocrina e Metabolica, Università Cattolica del Sacro Cuore, Policlinico A. Gemelli, L.go A. Gemelli 8, 00168, Rome, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: De Crea
authors.forename: Marco
authors.initials: M
authors.lastname: Raffaelli
authors.forename: Valentina
authors.initials: V
authors.lastname: Milano
authors.forename: Cinzia
authors.initials: C
authors.lastname: Carrozza
authors.forename: Cecilia
authors.initials: C
authors.lastname: Zuppi
authors.forename: Rocco
authors.initials: R
authors.lastname: Bellantone
authors.forename: Celestino P
authors.initials: CP
authors.lastname: Lombardi
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002116:Calcitonin / Q000097:blood*; D018276:Carcinoma, Medullary / Q000097:blood / Q000601:surgery*; D018278:Carcinoma, Neuroendocrine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D037981:Neck Dissection; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000097:blood / Q000601:surgery*; D013965:Thyroidectomy; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D002116:Calcitonin