title: Recurrent encephaloclastic cyst induced by intraventricular topotecan.
abstract: OBJECTIVE
  To report two rare cases of encephaloclastic cyst induced by intraventricular topotecan. To share our experience in diagnosing and treating this rare disease.
  
  
  BACKGROUND
  Ommaya reservoirs provide fast access and reliable drug delivery to cerebral spinal fluid. They are routinely utilized for the administration of intrathecal chemotherapy accounting for greater than 80% of cases for which they are used. Complications of Ommaya reservoir placement and its use consist of infectious and other late noninfectious causes. Encephaloclastic cysts provoked by intraventricular chemotherapy are very uncommon. The pathogenesis may result from alterations in CSF pulsations with retrograde flow of intraventricular chemotherapy into the brain parenchyma and subsequent development of a local chemical encephalopathy. It has been previously reported with methotrexate use but never with topotecan administration.
  
  
  METHODS
  We report two rare cases of encephaloclastic cyst with intraventricular topotecan use. The patients were diagnosed and treated at The University of Texas MD Anderson Cancer Center. They consented to the publication of their laboratory results and imaging studies for educational purposes.
  
  
  RESULTS
  The patients presented with metastatic cancers (breast/lung) complicated by leptomeningeal disease. Ommaya reservoirs were placed in both cases and patients were initiated on intraventricular topotecan at 0.4 mg twice weekly. After approximately 12 intraventricular treatments, both patients developed confusion, seizures and headaches. MRI of the brain demonstrated cystic dilatation of the brain parenchyma around the catheter that connects to the reservoir dome and delivers the drug to the intraventricular space. The catheter was surrounded by vasogenic edema. Catheters were removed and analyzed and were found to be intact. CSF analyses showed no evidence of infection or malignancy. Intraventricular topotecan was discontinued and both patients demonstrated sustained clinical and radiological responses.
  
  
  CONCLUSIONS
  These cases highlight an atypical complication of intraventricular use of topotecan with successful management.
authors.affiliation: Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States; Department of Neurology, The University of Texas Medical Branch, Galveston, TX, United States. Electronic address: dbmella@utmb.edu.
authors.forename: Divya B
authors.initials: DB
authors.lastname: Mella
authors.affiliation: Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
authors.forename: Carlos
authors.initials: C
authors.lastname: Kamiya-Matsuoka
authors.affiliation: Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States; Department of Neurology, The University of Texas Medical Branch, Galveston, TX, United States.
authors.forename: Bing
authors.initials: B
authors.lastname: Liao
authors.affiliation: Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
authors.forename: Sudhakar
authors.initials: S
authors.lastname: Tummala
authors.affiliation: Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States.
authors.forename: John
authors.initials: J
authors.lastname: de Groot
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D003560:Cysts / Q000209:etiology*; D016503:Drug Delivery Systems / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007276:Injections, Intraventricular / Q000009:adverse effects / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging; D008577:Meningeal Neoplasms / Q000188:drug therapy* / Q000556:secondary; D012008:Recurrence; D019772:Topotecan / Q000008:administration & dosage*
chemical_list: D019772:Topotecan
keywords: Encephaloclastic cyst; Intraventricular chemotherapy; Leptomeningeal disease; Ommaya reservoir; Topotecan