Patient description: The patient is a 34-year-old obese woman who comes to the clinic with weight concerns. She is 165 cm tall, and her weight is 113 kg (BMI: 41.5). In the past, she unsuccessfully used antiobesity agents and appetite suppressants. She is complaining of sleep apnea, PCO and dissatisfaction with her body shape. She is a high-school teacher. She is married for 5 years. She doesn't use any contraceptive methods for the past 4 months and she had no prior pregnancies. She rarely exercises and movement seems to be hard for her. She is not able to complete the four-square step test in less than 15 seconds. She does not smoke or use any drugs. Her BP: 130/80, HR: 195/min and her BMI is: 41.54. Her lab results: FBS: 98 mg/dl TG: 150 mg/dl Cholesterol: 180 mg/dl LDL: 90 mg/dl HDL: 35 mg/dl She is considering a laparoscopic gastric bypass.

Clinical trial eligibility criteria: eligible ages (years): 18.0-80.0,  Glioblastoma Multiforme Anaplastic Astrocytoma Anaplastic Oligodendroglioma Anaplastic Oligoastrocytoma Has the subject given written informed consent? Is the subject between 18 years old and 80 years old inclusive? Has the subject had histologically proven HGG with recurrence or progression following initial definitive therapy(s) such as surgery with or without adjuvant radiation therapy and/or chemotherapy (confirmed by diagnostic biopsy or contrast-enhanced MRI and evaluable by Macdonald criteria)? Note, if first recurrence of HGG is documented by MRI, an interval of at least 12 weeks after the end of prior radiation therapy is required unless there is either: i) histopathologic confirmation of recurrent tumor, or ii) new enhancement on MRI outside of the radiotherapy treatment field Does the patient have either (1) a single, enhancing tumor recurrence/progression that is ≤ 8 cm in greatest dimension, or (2) multiple enhancing tumor recurrences/progressions within the same surgical field where the sum of their greatest dimensions is ≤ 8 cm? Based on the pre-operative evaluation, is the tumor recurrence/progression a candidate for ≥ 80% resection? Has the subject elected not to undergo treatment with the Gliadel® wafer? Does the subject have a Karnofsky performance status ≥ 70? Does the subject have an absolute neutrophil count (ANC) ≥ 1500/mm3? Does the subject have an absolute lymphocyte count ≥ 500/mm3? Does the subject have a platelet count ≥ 100,000/mm3?  Has the subject received cytotoxic chemotherapy within the past 3 weeks (6 weeks for nitrosoureas) of the planned date of vector injection? Does the subject have, or has the subject had, within the past 4 weeks any infection requiring antibiotic, antifungal or antiviral therapy? Has the subject received Avastin® (bevacizumab) for this recurrence/progression, or within the 4 weeks prior to planned Visit 1? Does the subject have any bleeding diathesis, or must the subject take any anticoagulants, or antiplatelet agents, including NSAIDs that cannot be stopped for surgery? Does the subject have a history of allergy or intolerance to flucytosine? Is the subject HIV positive? Does the subject have any gastrointestinal disease that would prevent him or her from being able to swallow or absorb flucytosine? Has the subject received any investigational treatment within the past 30 days? Is the subject breastfeeding? Does the patient have a history of prior malignancy, excluding basal or squamous cell carcinoma of the skin, with an expected survival of less than five years?