THE INTRAMUSCULAR ADMINISTRATION OF GRANULOCYTE-COLONY-STIMULATING FACTOR AS AN ADJUNCT TO CHEMOTHERAPY IN PRETREATED OVARIAN-CANCER PATIENTS - AN ITALIAN-TRIALS-IN-MEDICAL-ONCOLOGY (ITMO) GROUP PILOT-STUDY

No published data are available concerning the activity and tolerabili ty of intramuscularly administered granulocyte colony-stimulating fact or (G-CSF) in humans. To fill this gap, 19 patients with advanced ovar ian cancer previously treated with at least one first-line chemotherap y cycle received the following myelosuppressive regimen: mitoxantrone (DHAD) 12 mg m(-2) i.v. on day 1; ifosfamide (IFO) 4 g m-(2) i.v. on d ays 1 and 2; mesna 800 mg m(-2) i.v. t.i.d. on days 1 and 2. G-CSF (Fi lgrastim) was given at a dose of 5 mu g/kg/day i.m. from day 6 to day 19, its pharmacokinetics being assessed in five patients. The neutroph il nadir was observed after a mean period of 8 days, and the neutrophi l count was <1.0 x 10(3) mm(-3) for a mean of 6 days during the cycle of chemotherapy. The neutrophil count fell after the withdrawal of G-C SF on the 19th day of treatment. The difference in absolute neutrophil count between day 19 and day 21 was statistically significant (P = 0. 0001); nevertheless, at day 21 no WHO grade 3-4 neutropenia was report ed. DHAD and IFO were respectively given at 95% and 93% of the planned dose. The pharmacokinetics of G-CSF i.m. seems to be similar to that of the drug given subcutaneously. No evidence of cumulative myelosuppr ession was observed. G-CSF was well tolerated and no complications wer e observed at the injection sites. In conclusion, if the results obtai ned in this pilot study regarding the activity of i.m. G-CSF are confi rmed by a randomised trial, the intramuscular administration of G-CSF could become a valid alternative for patients who dislike the subcutan eous route and who are being treated with chemotherapy that does not i nduce profound thrombocytopenia.