title: Ghost Tumors of the Central Nervous System: Definition, Clinical Implications, and Proposal of Classification.
abstract: BACKGROUND
  A ghost tumor (GhT) is a space-occupying lesion with radiologic features consistent with the diagnosis of tumor that on further investigation is revealed not to be a tumor, although definitions in the literature are inconsistent, and the incidence of GhT remains undefined.
  
  
  METHODS
  A review of the pertinent literature was performed to identify pediatric patients in whom a misleading initial diagnosis of space-occupying lesion was described. Analysis of the differentiating features of the final diagnosis and related clinical and radiologic issues was performed.
  
  
  RESULTS
  GhT may be categorized as follows: GhT I, lesions spontaneously disappearing during follow-up, also known as "vanishing tumors"; GhT II, nonneoplastic space-occupying lesions showing a tumor appearance, also known as "tumor-like lesions"; GhT III, anatomic variants of normal structures mimicking a tumor, also defined as "false tumors." The most deceptive conditions and critical points in the differential diagnosis of these cases were discussed.
  
  
  CONCLUSIONS
  GhT is an entity with significant implications in regard to treatment and outcome. In this context, the integration of clinical and radiologic clues is crucial for a careful differential diagnosis and a consistent diagnostic approach, which is necessary for adequate decision making regarding management. A thorough radiologic work-up is mandatory. Atypical radiologic images should raise a high level of suspicion, including incidental lesions, which are encountered with increasing frequency in daily practice as a result of greater access to radiologic examinations, increasing sensitivity of imaging, and the impact of defensive medicine. A wait-and-see policy should be considered whenever indicated.
authors: Division of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy. Electronic address: paolo.frassanito@gmail.com.
authors: Paolo
authors: P
authors: Frassanito
authors: Division of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
authors: Gianpiero
authors: G
authors: Tamburrini
authors: Division of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
authors: Luca
authors: L
authors: Massimi
authors: Division of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
authors: Massimo
authors: M
authors: Caldarelli
authors: Division of Pediatric Neurosurgery, Catholic University Medical School, Rome, Italy.
authors: Concezio
authors: C
authors: Di Rocco
mesh_terms: D016543:Central Nervous System Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000601:surgery; D002648:Child; D003937:Diagnosis, Differential; D005189:False Positive Reactions; D006801:Humans; D011859:Radiography
keywords: Central nervous system; False tumor; Ghost tumor; Mimicking tumor; Tumor-like lesion; Vanishing tumor