Megatherapy with hematopoietic stem cell rescue as a preoperative treatment in unresectable pediatric malignancies

To improve the quality of life and prognosis of the patients with advanced pediatric malignant tumors, the authors have used megatherapy (MT) with hematopoietic stem cell transplantation (SCT) before surgery. To elucidate the impact of preoperative MT on the treatments of pediatric advanced malignancies, the authors reviewed the timing of surgery, preoperative condition, postoperative recovery, and outcome.

Between 1991 and 2001, 24 children with malignant tumors received MT with SCT before surgery, and 19 tumors were resected after SCT. These tumors included 12 neuroblastomas, 2 hepatic tumors, 2 peripheral primitive neuroectodermal tumors, one rhabdomyosarcoma, one Wilms' tumor, and one yolk sac tumor.

The mean duration of white blood cell (WBC) recovery (>1,000/mm3) and platelet recovery (>50,000/mm3) after SCT was 17.1 and 42.5 days, respectively. Distant metastases were controlled in 9 of 15 cases. The tumors were resected completely in 14 cases (73.7%), and complete remission (CR) was achieved after surgery in 9 cases (47.4%). There was no postoperative complication or remarkable functional impairment. At 7 months to 7 years after diagnosis, 9 patients are alive without disease, one with disease, 6 have died of recurrent tumor, and 2 have died of chemotherapy-associated complications.

The current study suggested that MT with SCT before surgical resection contributes to increase in resectability and achieving CR. In the treatment of advanced pediatric malignancies, especially in the case of unresectable tumor, preoperative MT with SCT should be considered.