The time for the neutrophil count to recover after subcutaneous injection of filgrastim BS1 or lenograstim was studied in patients suffering from neutropenia following preoperative combined chemotherapy using docetaxel, nedaplatin, or cisplatin (in divided doses for 5 days)and 5-fluorouracil for oral cancer. 1. There was no significant difference in the minimum leukocyte and neutrophil counts after chemotherapy. 2. There was no significant difference in the maximum leukocyte and neutrophil counts after chemotherapy. 3. Time for leukocytes to recover from their minimum count(>4,000/mm3)or for neutrophils to recover from their minimum count(>2,000/mm3)and the number of days on which treatment was administered tended to be shorter in the filgrastim BS1 group. Thus, it was concluded that filgrastim BS1 is just as effective as other prior G-CSF agents in treating patients suffering from neutropenia following chemotherapy(TPF therapy).