title: Persistent cervical thymus with a small cyst in a newborn infant.
abstract: A boy, aged 1 month, who showed a tumour mass in the right neck, is presented. Operation disclosed that the tumour was a cervical thymus with a small cyst. The cervical thymus degenerated gradually into hypoplasia or thymic cyst due to the abnormal descent of the thymus. It is rare that cervical thymus and/or thymic cyst is detected before the age of one year.
mesh_terms: D003937:Diagnosis, Differential; D006801:Humans; D007223:Infant; D008297:Male; D008476:Mediastinal Cyst / Q000151:congenital* / Q000473:pathology; D009333:Neck / Q000473:pathology; D013950:Thymus Gland / Q000002:abnormalities* / Q000473:pathology