The main objective of this study is to establish an optimal threshold Early parathormon (PTH) assay in order to exclude hypoparathyroidism , that is to say to obtain a negative predictive value of hypoparathyroidism highest possible.

Inclusion Criteria:

• Patients consecutively operated on between February 1, 2012 and December 1, 2013
• Total thyroidectomy +/- lymphadenectomy
• Respect of clinicobiological protocol presented above
• The ( the ) patient ( e) was informed ( e) on the implementation of the study 's objectives, constraints and patient rights
• The ( the ) patient ( e) is under ( e) at least 18 years

Exclusion Criteria:

• The ( the ) patient ( e) is under guardianship, curatorship or under guard saves justice
• It is not possible to give to ( the ) patient ( e) informed information
• History of cervical radiotherapy
• Previous history of dysfunction of the parathyroid glands
• Previous history of surgery of the parathyroid glands
• A history of kidney failure or hepatocellular
• History of osteomalacia or Paget's disease
• unhealed cancer antecedent
• History of sarcoidosis

Included patients underwent total thyroidectomy from 1 February 2012 to 1 December 2013 at the Nîmes University Hospital