A Study of Bevacizumab to Prevent Malignant Ascites

Inclusion Criteria: * Persistent or symptomatic ascites with positive cytology secondary to any histologically confirmed tumor type not amenable to cytoreductive surgery or additional chemotherapy * Patients may enroll in this study irrespective of previous therapy including diuretics, surgery, chemotherapy, immunotherapy and radiation therapy * Must have received a minimum of two paracentesis procedures and a trial of diuretic therapy within 60 days of study entry * Age Restrictions: 18 years and older * Life Expectancy: 12 weeks or more * ECOG Performance Status: 0 -3 * Able and willing to provide informed consent and comply with study and/or follow-up procedures * Normal organ and marrow function as defined by: Leukocytes \>/= 3,000/mcL; Absolute neutrophil count \>/= 1,500/mcL; Platelets \>/= 100,000/mcL; Total bilirubin within normal institutional limits; AST (SGOT)/ALT(SGPT) \</= 2.5 X institutional upper limit of normal (ULN); Creatinine within normal institutional limits OR Creatinine clearance \>/+ 60 mL/min for patients with creatinine levels above the institutional normal; Serum Potassium within normal institutional limits; Serum Sodium within normal institutional limits Exclusion Criteria: * Patients having received Bevacizumab as part of the treatment of their malignancy within 60 days prior to study entry * Current, recent (within 30 days of the first infusion of this study) or planned administration of chemotherapy (including all routes of administration), immunotherapy, biologic therapy, radiation therapy or any other anti-VEGF therapy (e.g., tyrosine kinase inhibitors) * Current, recent (within 30 days of the first infusion of this study), or planned participation in any other experimental drug study * Pregnant women; A serum pregnancy test will be given to females of childbearing potential prior to study enrollment and the participant must agree to use adequate contraception (barrier or hormonal methods) prior to study entry and for the duration of study participation. * Un-controlled hypertension (defined as systolic blood pressure \> 150 mmHg and/or diastolic blood pressure \> 100 mmHg * History of hypertensive crisis or hypertensive encephalopathy * New York Heart Association (NYHA) Grade II or greater congestive heart failure * History of myocardial infarction, unstable angina, stroke or transient ischemic attack within 6 months prior to study entry * Known CNS disease, except for treated brain metastasis. * Significant vascular disease (e.g., aortic aneurysm, requiring surgical repair or recent peripheral arterial thrombosis) within 6 months prior to study entry * History of hemoptysis (\>/= 1/2 teaspoon of bright red blood per episode) within 1 month prior to study entry * Evidence of bleeding diathesis or significant coagulopathy (in the absence of therapeutic anticoagulation) * Major surgical procedure, open biopsy, or significant traumatic injury within 28 days prior to study entry or anticipation of need for major surgical procedure during the course of the study * Core biopsy or other minor surgical procedure, excluding placement of a vascular access device or paracentesis/thoracentesis, within 7 days prior to study entry * History of abdominal fistula or gastrointestinal perforation within 6 months prior to study entry * Any bowel obstruction that has not fully recovered despite medical or surgical intervention prior to study entry * Evidence of bowel wall thickening outside the site of the known primary malignancy on baseline radiographs * Serious, non-healing wound, active ulcer, or untreated bone fracture * Proteinuria as demonstrated by a Urine Protein/Creatinine ration \>/= 1.0 at screening * Known hypersensitivity to any component of bevacizumab * Intrathoracic lung carcinoma of squamous cell histology.