Laterocervical septated lesions are infrequent in adults, and their etiological diagnosis is difficult. The authors report about four cases in which an exploration with imaging and an anatomical control were performed. Two etiologies are specially interesting, either because of their remarkable features with imaging (cystic lymphangioma) or because they require formal identification (metastatic adenopathy from thyroid or ovarian papillary carcinomas). While modern imaging can confirm the diagnosis, and sometimes define the treatment (cystic lymphangioma), the surgical exeresis of such lesions remains imperative in all cases of atypical appearances, in order to avoid leaving a prevailing lymph node metastasis unrecognized.