Clinical Scorecard: Combination of high-dose thiotepa and melphalan followed by autologous hematopoietic stem cell transplantation in pediatric patients with solid tumors, including brain tumors

At a Glance

Key Highlights

• Thiotepa penetrates CNS effectively, achieving cerebrospinal fluid concentrations >90% of serum levels
• Combination regimen: thiotepa 200 mg/m2/day IV on days −12, −11, −5, −4 plus melphalan 70 mg/m2/day IV on days −11, −5, −4 before HSCT
• Expanded access program in Japan demonstrated good tolerability and high survival rates in pediatric solid tumor patients

Guideline-Based Recommendations

Diagnosis

• Confirm diagnosis of pediatric solid or brain tumor requiring autologous HSCT
• Assess ECOG performance status 0–2 within 14 days before treatment
• Ensure normal hepatic, renal, and cardiac function prior to treatment

Management

• Administer thiotepa and melphalan as high-dose chemotherapy prior to autologous HSCT
• Dose adjustments or discontinuation based on renal function (eGFR thresholds) and investigator judgment
• Avoid treatment if eGFR <45 ml/min/1.73 m2 (≥18 years) or <75 ml/min/1.73 m2 (<18 years) on day −7

Monitoring & Follow-up

• Monitor renal function (eGFR) before and during treatment
• Assess for adverse events and tolerability during high-dose chemotherapy and post-transplant period
• Regular follow-up for survival and disease status post-HSCT

Risks

• Potential myelosuppression and need for blood transfusions
• Risk of impaired drug metabolism or excretion in patients with organ dysfunction
• Contraindications include active infection, hypersensitivity to study drugs, and recent investigational treatments

Patient & Prescribing Data

Pediatric patients aged ≥2 years with solid or brain tumors undergoing autologous HSCT

Thiotepa combined with melphalan is well tolerated with high survival rates; requires careful renal function monitoring and dose adjustments

Clinical Best Practices

• Ensure thorough pre-treatment evaluation including renal, hepatic, cardiac function and performance status
• Use thiotepa and melphalan dosing schedule as per protocol with adjustments for renal impairment
• Exclude patients with recent treatments, active infections, or contraindications to study drugs
• Provide informed consent and contraception counseling as appropriate
• Conduct treatment in specialized centers with capacity for intensive supportive care and HSCT

References

• Japanese Society of Pediatric Hematology/Oncology database
• Phase I study of thiotepa as HDT with autologous HSCT in Japanese patients
• Thiotepa approval in Japan for HDT before autologous HSCT