EFFECT OF RECOMBINANT HUMAN GRANULOCYTE-COLONY-STIMULATING FACTOR (R-METHUG-CSF) AS AN ADJUNCT TO LARGE-FIELD RADIOTHERAPY - A PHASE-I STUDY

Purpose: To test the feasibility of recombinant human granulocyte colo ny stimulating factor application during large-field radiotherapy. Met hods and Materials: Fifteen patients with clinically and histologicall y proven malignancy who received large-field radiotherapy entered this study. Administration of recombinant granulocyte colony stimulating f actor (G-CSF) at a dose of 300 mu g subcutaneously was started on Frid ay and was continued on Saturday and Sunday after the first radiothera py treatment, which began on the Monday before. In this way four cours es of G-CSF were applied every Friday, Saturday, and Sunday during the radiotherapy period, Absolute neutrophil cell (ANC) and blood counts were monitored twice a week and compared to a second group of 15 patie nts who received large-field radiotherapy without G-CSF. Before and at the end of every cycle of G-CSF, ANC, blood counts, and biochemistry were measured, We compared the myelotoxicity of the patients treated w ith G-CSF with 15 patients without G-CSF treated at the same period wi th large-field radiotherapy, in match pair technique. Results: G-CSF i ncreased the ANC throughout the period of irradiation, and the treatme nt time needed for completing radiotherapy was shorter in the group wh o received G-CSF, Fourteen of 15 patients who received G-CSF treatment completed large-field radiotherapy without pause. Only 1 of 15 patien ts not receiving G-CSP was able to receive radiation treatment on sche dule, Patients receiving G-CSF completed treatment with the mantle-fie ld technique in 24 days and those with the abdominal bath technique in 26.5 days. Conversely, patients treated without G-CSF completed treat ment with the mantle-field technique in 30.5 days and those with the a bdominal bath technique in 36 days. The most frequent side effect was musculoskeletal pain. Conclusion: The prophylactic application of G-CS F during large-field radiotherapy before the onset of neutropenia was feasible in this schedule. Whether or not this shortening of treatment duration will translate into an improvement in efficacy is not clear.