Study of Doxorubicin and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) and Intraoperative Brachytherapy for Unresectable or Refractory Pelvic and Abdominal Rhabdomyosarcoma and Undifferentiated Sarcomas in Children

Inclusion Criteria:

1. Age 1-6 years inclusive
2. Histologically proven RMS (with fusion status) or undifferentiated sarcoma of the pelvis or abdomen, group 3 (as defined by the IRS, intergroup rhabdomyosarcoma study group staging system seen in addendum 1)
3. Radiologic workup must demonstrate that the disease is confined to the abdominal cavity and/or is not metabolically active on PET (Positron Emission Tomography scan), outside of the abdominal cavity.
4. Patients must have a minimum expected duration of survival of greater than 6 weeks as determined and documented by the attending surgeon or medical oncologist.
5. Patients must not have any systemic illness which precludes them from being an operative candidate as determined by anesthesia preoperative evaluation. This includes but is not limited to, sepsis, liver failure, renal failure, cardiovascular failure, pulmonary failure.
6. Patients must have fully intact mental status and normal neurologic abilities. Intact mental status is defined by 'the capacity to identify and recall one's identity and place in time and space. Assessment of mental status and documentation of fully intact mental status by pediatric criteria, will be completed using physical and mental exam by the referring doctor or oncologist.
7. Patients must have adequate renal function defined as creatinine clearance or radioisotope GFR (glomerular filtration rate) \>/=70mL/min/1.73m\^2 or a serum creatinine based on age/gender less than the listed value in the table below: 1 to \<2 years 0.6mg/dL for both males and females, 2 to \<6 years 0.8mg/dL for both males and females, 6 to \<10 years 1.0mg/dL for both males and females
8. Patients will be eligible if the WBC (white blood cell count) is ≥2000/µl or ANC (absolute neutrophil count) is ≥1,500 and platelets are ≥ 100,000/mm3
9. Patients will be eligible if serum total bilirubin and liver enzymes are ≤ 2 times the upper limit of normal
10. Patients must be recovered from any toxicity from all prior chemotherapy, immunotherapy, or radiotherapy and be at least 14 days past the date of their last treatment

Exclusion Criteria:

1. Patients will be ineligible if they have any concomitant cardiopulmonary disease which would place them at unacceptable risk for a major surgical procedure
2. Patients will be ineligible if they have disease outside of the abdominal cavity which is uncontrolled or PET avid.
3. Patients will be ineligible if they have a baseline neurologic toxicity of Grade 3 or greater.