Dose-intensification of procarbazine, CCNU (lomustine), vincristine (PCV) with peripheral blood stem cell support in young patients with gliomas.

BACKGROUND

The regimen of procarbazine, CCNU, and vincristine is active against gliomas. Previous attempts at dose-intensification have been unsuccessful because of delayed and cumulative myelosuppression. We sought to determine whether peripheral blood stem cell (PBSC) infusions would allow dose-escalation and time compression.

PROCEDURE

Eleven patients, age 2.8-35.9 years, with newly diagnosed (n = 10) or recurrent (n = 1) gliomas underwent PBSC harvesting after mobilization with G-CSF. Chemotherapy consisted of CCNU 130 mg/m2 on day 0, vincristine 1.5 mg/m2 on days 0 and 7, and procarbazine 150 mg/m2 on days 1-7. PBSCs were reinfused on day 9 of each course. Four courses of chemotherapy were administered 28 days apart or when counts recovered. Involved field radiation was administered to newly diagnosed high-grade glioma patients following recovery from chemotherapy.

RESULTS

Compared to the standard PCV regimen given every 6 weeks, dose intensity received was 1.7- and 1.8-fold greater for CCNU and procarbazine. Chemotherapy was delivered on time in 33/41 (80.5%) courses. Four courses (9.8%) were complicated by absolute neutrophil counts < 200/microL; platelet nadirs < 50,000/microL occurred in two courses (4.9%). Fever with neutropenia complicated three courses. Eight of 9 patients with measurable disease had an objective decrease in tumor size and/or decreased enhancement. Median survival for patients with high-grade gliomas (n = 6) was 13 months.

CONCLUSIONS

Dose-intensification of PCV is possible using PBSCs.