Clinical usefulness of macrophage colony-stimulating factor for ovarian cancers: Long-term prognosis after five years

We performed a randomized double blind study between 1992 and 1995 in which 214 patients with FIGO stage I to III ovarian cancers received administration of 10(6) units (low dose group) or 8x10(6) units (high dose group) of macrophage colony-stimulating factor (M-CSF) after cyclophosphamide/adriamycin/cisplatin (CAP) therapy. The period required to finish a set of intensive chemotherapy, which was the primary endpoint, was significantly shortened (p=0.0004), and the incidence of febrile neutropenia significantly decreased (p=0.04). In this study, we followed the patients for a prolonged period. The patients were divided into two groups: patients with complete tumor excision and those with incomplete excision, then the relapse rate and survival rate 5 years after initiation of the clinical study were compared. The relapse rate tended to be lower in the high dose group than in the low dose group in patients with no residual tumor (p=0.0750). However, there was no difference in the relapse rate between the two dose groups in patients with residual tumor. Although there were no significant differences in the survival rate between the high and low dose groups in patients with or without residual tumor, the survival rate in mucinous adenocarcinoma patients with no residual tumor was 64.3% in the low dose group (n=14) and 92.3% in the high dose group (n=14), showing a significantly higher rate (p=0.0436), and the survival rate tended to be higher in the high dose group in patients with serous adenocarcinoma (p=0.0786). Furthermore, in patients aged 40 years or younger with no residual tumor, the survival rates were 73.9 and 100% in the low and high dose groups, respectively, showing a significantly higher rate in the high dose group (p=0.0310). Our results suggest that administration of M-CSF can improve the long-term prognosis of ovarian cancer patients with no residual tumor, but further prospective randomized trials with a primary endpoint of relapse-preventing effect are needed.