Thirty-three patients with incurable neoplasms resistant to standard therapy received vinorelbine 8 mg/m2 to 10 mg/m2 per day by continuous infusion with concurrent administration of recombinant human granulocyte colony-stimulating factor 5 microm/m2 per day. The duration of the vinorelbine infusion was individualized; the infusion was continued until early evidence of hematopoietic toxicity was noted. The concurrent administration of recombinant human granulocyte colony-stimulating factor permitted a substantial increase in dose intensity of the anticancer agent without a corresponding increase in drug toxicity. There was no evidence that the antitumor effect of vinorelbine was compromised by the concurrent administration of recombinant human granulocyte colony-stimulating factor.