title: An analysis of intracranial epidermoid tumors with malignant transformation: treatment and outcomes.
abstract: OBJECTIVE
  While typically benign, epidermoid tumors upon rare occasion can undergo malignant transformation, which carries a poor prognosis. Here, we reviewed treatment strategies and analyzed outcomes for every case of malignant epidermoid tumor reported since its original description in 1912.
  
  
  METHODS
  A comprehensive literature review identified all reported cases of malignant transformation of intracranial epidermoid tumor. Treatments were categorized as follows: palliative management, stereotactic radiosurgery (SRS), chemotherapy, and surgery plus multiple (2+) adjuvant therapies. Survival data of these groups were compared to treatment outcomes for patients receiving only surgical resection, as reported in our previous study.
  
  
  RESULTS
  We identified 58 cases of intracranial epidermoid tumor with malignant degeneration. Average survival regardless of therapy was 11.8 months. Mean survival outcomes for groups treated with palliative management, chemotherapy, SRS, and multiple postoperative adjuvant therapies were 5.3 months, 25.7 months, 29.2 months, and 36.3 months, respectively. Outcomes for the groups including SRS, chemotherapy, and multiple post-operative adjuvant therapies were statistically significant compared to surgical resection alone.
  
  
  CONCLUSIONS
  While there remains a lack of consensus regarding the best approach to the management of patients with malignant epidermoid tumors, our systematic analysis characterizes and confirms the added benefit of SRS, chemotherapy, and multimodal adjuvant therapies.
authors.affiliation: UCLA Department of Neurological Surgery, University of California Los Angeles, Los Angeles, CA 90095-1761, USA.
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Nagasawa
authors.forename: Winward
authors.initials: W
authors.lastname: Choy
authors.forename: Marko
authors.initials: M
authors.lastname: Spasic
authors.forename: Andrew
authors.initials: A
authors.lastname: Yew
authors.forename: Andy
authors.initials: A
authors.lastname: Trang
authors.forename: Heather M
authors.initials: HM
authors.lastname: Garcia
authors.forename: Isaac
authors.initials: I
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000473:pathology* / Q000628:therapy*; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000628:therapy*; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D055756:Meningeal Carcinomatosis / Q000209:etiology; D008875:Middle Aged; D019635:Neurosurgical Procedures; D010166:Palliative Care; D016634:Radiosurgery; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents