Increasing and planned dose intensity of doxorubicin, cyclophosphamide and etoposide (ACE) by adding recombinant human methionyl granulocyte colony-stimulating factor (G-CSF; filgrastim) in the treatment of small cell lung cancer (SCLC). Medical Research Council Lung Cancer Working Party.

The aim of this Phase II study was to test the feasibility of intensifying standard chemotherapy in the treatment of small cell lung cancer (SCLC) by reducing the interval between cycles from 3 to 2 weeks by adding recombinant human methionyl granulocyte colony-stimulating factor (G-CSF; filgrastim) to shorten the duration of neutropenia following each cycle. Thirty-two patients with SCLC were prescribed six cycles of 2-weekly doxorubicin 50 mg/m2 and cyclophosphamide 1 g/m2 on day 1, and etoposide 120 mg/m2 i.v. on days 1, 2 and 3 (ACE), plus filgrastim in a fixed dose of 300 micrograms s.c. on days 4-14 of each cycle. Three patients died during the treatment period and a further nine had chemotherapy terminated before the sixth cycle, all nine because of toxicity. All 32 patients have been followed up for at least 21 months; 14 (44%) were alive at 12 months and the median survival period was 356 days. Of the 127 intervals between cycles of chemotherapy, 74 (58%) were of the prescribed 14 days, 18 (14%) of 15-20 days, 25 (20%) of 21 days, and 10 (8%) were longer. The results were best during the first four cycles, during which 71% of the 83 intervals were of 14 days and a further 10% were less than 21 days. The main reason for delay was haematological toxicity in 37 of the 53 instances. Symptoms of myelosuppression occurred in 23 patients, but at 14 days after a cycle of chemotherapy, all 127 available neutrophil granulocyte counts were normal. Twenty-one patients received blood transfusion and five platelet transfusion. The only adverse effects attributed to filgastrim were episodes of rash, throat swelling, anorexia and shivering, affecting one patient. We conclude that the policy of adding filgrastim allows the dose intensity of ACE chemotherapy to be increased by reducing the intervals between cycles. The findings reinforce those of a parallel study involving lenograstim.