• To find the highest tolerable dose of cisplatin given to pediatric patients undergoing extensive surgery to remove all visible tumor from the abdominal cavity. [ Time Frame: 2 Years ] [ Designated as safety issue: Yes ]
  

Inclusion Criteria:

• Age greater than or equal to 3 and less than or equal to 18 years
• Histologically proven diffuse peritoneal or retroperitoneal tumor from the following histologies: adenocarcinoma of the gastrointestinal tract, desmoplastic round cell tumor, late stage neuroblastoma, ovarian germ cell, sarcoma, adrenocorticocarcinoma, Wilms', rhabdomyosarcoma. (target groups: desmoplastic small round cell tumor (DSRCT), neuroblastoma, and recurrent tumors). If tumors are outside the abdominal cavity, the tumors must be controllable.
• All patients must have refractory or recurrent tumors with no known curative treatment options.
• Radiologic workup must demonstrate that the disease is confined to the abdominal cavity. If tumors are outside the abdominal cavity, the tumors must be able to be controlled.
• Radiologic workup or prior abdominal exploration must be consistent with disease which can be debulked to a residual size of less than or equal to1 mm thickness per tumor deposit
• Patients must have minimum expected duration of survival of greater than 6 weeks
• Patients must not have any systemic illness which precludes them from being an operative candidate. This includes but is not limited to sepsis, liver failure, pregnancy, lactating females.
• Patients must have fully intact mental status and normal neurologic abilities.
• Patients must have adequate renal function (serum creatinine </= 1.5 without history dialysis or renal failure)
• Patients will be eligible if the WBC is > or =2,000/ul or ANC is > or =1,500, or platelets are > or = 100,000/mm^3
• Patients will be eligible if serum total bilirubin and liver enzymes (ALT or AST) are </= 2 times the upper limit of normal
• 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
• If tumors are outside the abdominal cavity, the tumors must be controllable.

Exclusion Criteria:

• Patients who have failed previous continuous hyperthermic intraperitoneal perfusion with platinum therapy will be ineligible
• Patients with tumors that are unable to be controlled outside the abdominal cavity will be ineligible
• Patients will be ineligible if they have any concomitant cardiopulmonary disease which would place them at unacceptable risk for a major surgical procedure
• Patients will be ineligible if they have a baseline neurologic toxicity of Grade 3 or greater (because of the potential neurotoxicity associated with platinum)