In front of a cervical mass of unknown nature, despite various examinations carried out beforehand (biological, radiological, endoscopic, cytological examinations ...). The intervention consists of a cervical exploration to identify the anatomical site of the lesion and its origin. The cervical mass will be removed in whole or in part, to allow a histological examination to be carried out during the operation (extemporaneous examination with immediate analysis but not definitive result and whose reliability is not 100%), a bacteriological examination looking for germs or whatever. Depending on the results, the operation can be continued to complete the surgical procedure. Thus, lymph node dissection, thyroidectomy, etc. can be performed.