title: Presurgical assessment of the tumor burden of familial medullary thyroid carcinoma by calcitonin testing.
abstract: BACKGROUND
  Early diagnosis of familial medullary thyroid carcinoma (MTC) is currently done by genetic analysis. These techniques have replaced calcitonin stimulation testing, which was previously used for this purpose. Some studies suggest a relationship between MTC spread and calcitonin levels. The aim of this study was to assess whether the tumor burden of MTC associated with multiple endocrine neoplasia type 2A (MEN 2A) syndrome can be estimated from the plasma calcitonin values before surgery.
  
  
  METHODS
  We retrospectively studied the relationship of basal and peak calcitonin values before thyroidectomy with histopathologic findings in 53 patients with MEN 2A syndrome from 14 families. The MTC was classified according to TNM staging. Analysis of variance was used for statistical analysis complemented with equality contrasts for pairs of means by the least significant difference method with a Student's t-test and with the Bonferroni's adjustment.
  
  
  RESULTS
  A positive association was found between tumor stage and basal and peak calcitonin levels. There were significant differences between the following: mean basal concentrations of patients with C cell hyperplasia (CCH) (34.3 pg/mL) and TNM stage II (1,097.4 pg/mL), p < 0.01; CCH and TNM stage III (2,940.8 pg/mL), p < 0.001; TNM stage I (165.3 pg/mL) and stage II (1,097.4 pg/mL), p < 0.01, and between TNM stages I and III, p < 0.001. Poststimulation mean concentrations were different between CCH (48.7 pg/mL) and TNM I (514.2 pg/mL), p < 0.001.
  
  
  CONCLUSIONS
  Preoperative calcitonin testing may be useful for assessing tumor spread and should be considered when deciding the extent of surgery for MEN 2A MTC.
authors.affiliation: Department of Endocrinology, Hospital Universitario Virgen de la Arrixaca, Murcia, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Pomares
authors.forename: Jose M
authors.initials: JM
authors.lastname: Rodríguez
authors.forename: Francisco
authors.initials: F
authors.lastname: Nicolás
authors.forename: Joaquin
authors.initials: J
authors.lastname: Sola
authors.forename: Manuel
authors.initials: M
authors.lastname: Canteras
authors.forename: María
authors.initials: M
authors.lastname: Balsalobre
authors.forename: Mercedes
authors.initials: M
authors.lastname: Pascual
authors.forename: Pascual
authors.initials: P
authors.lastname: Parrilla
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Tébar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002116:Calcitonin / Q000097:blood*; D018276:Carcinoma, Medullary / Q000097:blood* / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D018813:Multiple Endocrine Neoplasia Type 2a / Q000097:blood* / Q000473:pathology / Q000601:surgery; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011300:Preoperative Care; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000097:blood* / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D013965:Thyroidectomy
chemical_list: D015415:Biomarkers; D002116:Calcitonin