Irinotecan, Temozolomide and Bevacizumab in Combination With Existing High Dose Alkylator Based Chemotherapy for Treatment of Newly Diagnosed Patients With Desmoplastic Small Round Cell Tumor

Inclusion Criteria:

* Age greater than or equal to 1 year, less than 30 years
* Newly diagnosed, previously untreated patients with histologically or molecularly confirmed DSRCT
* Adequate hematologic function:
* Absolute neutrophil count ≥ 1,000/mm3
* Platelet count ≥ 100,000/mytm3
* Adequate renal function:
* Normal creatinine for age OR
* Creatinine clearance or radioisotope GFR ≥ 70ml/min/1.73 m2
* Adequate hepatic function:
* Total bilirubin ≤ 1.5 x the ULN for age
* AST ≤ 2.5 x the ULN for age \[in the absence of hepatic involvement of tumor\]
* Normal cardiac function
* Shortening fraction greater than or equal to 28% by echocardiogram OR
* Left ventricular ejection fraction (LVEF) greater than or equal to 50% on technetium-99m pertechnetate radionuclide cineangiography (MUGA) or echocardiogram
* Hypertension must be well controlled on stable doses of medication for at least two weeks prior to enrollment.
* Patients must consent to an indwelling central venous catheter.
* Sexually active patients of reproductive potential must be willing to use an effective method of contraception.

Exclusion Criteria:

* Prior chemotherapy or radiotherapy
* Pregnant or breastfeeding females
* Patients with documented chronic non-healing wound, ulcer or bone fracture.
* Incomplete healing from previous oncologic or other major surgery.
* Surgical procedures:

Patients who have undergone major surgery (including open biopsy, thoracotomy, organ resection, exploratory laparotomy, arteriovenous grafts) \<28 days prior to enrollment will have bevacizumab dosing delayed as outlined in section 9.1

* Patients must be at least 48 hours from placement of central catheter before receiving first dose of bevacizumab
* Minor surgical procedures (needle/laparoscopic core biopsies) for limited purposes of tissue retrieval will be allowed. Patients should not receive the first planned dose of bevacizumab until the wound is healed and 7 days have elapsed since the procedure.
* Evidence of bleeding diathesis or significant coagulopathy (in the absence of therapeutic anticoagulation).
* Thrombosis:
* Patients must not have had a deep venous or arterial thrombosis (non-central venous catheter related) within the last three months prior to study entry.
* Patients with cerebrovascular accident or transient ischemic attack within 6 months of therapy are excluded
* History of abdominal fistula, gastrointestinal perforation, or intra-abdominal abscess within 6 months prior to study entry.
* CNS status: Patients must not have known CNS metastases or leptomeningeal disease.

Screening with brain imaging is not required for asymptomatic patients. Proteinuria: Urine protein: creatinine ratio greater than or equal to 1.0

* Uncontrolled hypertension (defined as SBP and/or DBP \> 95th percentile for age)
* Prior history of hypertensive crisis or hypertensive encephalopathy
* NYHA Grade II or greater congestive heart failure
* History of myocardial infarction or unstable angina within 12 months prior to Day 1
* History of stroke or transient ischemic attack
* Significant vascular (e.g., aortic aneurysm, requiring surgical repair or recent peripheral arterial thrombosis) within 6 months prior to Day 1
* History of hemoptysis (greater than or equal to 1/2 teaspoon of bright red blood per episode) within 1 month prior to Day 1
* Known hypersensitivity to any component of bevacizumab