Veno-occlusive disease (VOD) after hematopoietic stem cell transplantation (HSCT) remains the major complication. VOD occurs in 11-31% of pediatric HSCT and the mortality reaches up to 50%.

Prostaglandin E1 (PGE1) have been reported to prevent and relieve the severity of VOD by Gluckman et al.. Lipo-PGE1 is a transporter of PGE1, which is superior in concentrating PGE1 and acts for prolonged time. Because of the prolonged effective time, lipo-PGE1 acts comparable effects by 1/4~1/8 of PGE1 dose. Empirically, pediatric HSCT centers adopt lipo-PGE1 in dose of 1 mcg/kg/day (0.042 mcg/kg/hr), which is 1/7 of the dose recommended by Gluckman, et al. This prospective study will investigate the concentration of lipo-PGE1 with preventive lipo-PGE1 with empirical dose (1 mcg/kg/day).

Primary Objective: To evaluate the pharmacokinetics of lipo-PGE1. Secondary objective: To evaluate the relation between lipo-PGE1 concentration and VOD occurrence, severity.

Inclusion criteria

1. Patients undergoing HSCT with high risk of VOD who cannot use low dose heparin.

   • high risk of VOD : previous radiotherapy, liver function abnormality, children, conditioning regimen including busulfan or total body irradiation
   • contraindication of heparin : low platelet count, bleeding tendency, allergy

2. Patients (or one of parents if patients age < 19) should sign informed consent.

Exclusion criteria

1. Patient with heart failure.
2. Patient with bleeding (intracranial hemorrhage, gastrointestinal tract bleeding, hemoptysis).
3. History of hypersensitivity reaction as shock to lipo-PGE1.
4. Psychiatric disorder that would preclude compliance.
5. If the clinician decides that there is a condition improper for the clinical study.

Inclusion Criteria:

1. Patients undergoing HSCT with high risk of VOD who cannot use low dose heparin.

   • high risk of VOD : previous radiotherapy, liver function abnormality, children, conditioning regimen including busulfan or total body irradiation
   • contraindication of heparin : low platelet count, bleeding tendency, allergy

2. Patients (or one of parents if patients age < 19) should sign informed consent.

Exclusion Criteria:

1. Patient with heart failure.
2. Patient with bleeding (intracranial hemorrhage, gastrointestinal tract bleeding, hemoptysis).
3. History of hypersensitivity reaction as shock to lipo-PGE1.
4. Psychiatric disorder that would preclude compliance.
5. If the clinician decides that there is a condition improper for the clinical study.