Association of Chemotherapy-induced Leucopenia with Treatment Outcomes in Advanced Non-small-cell lung Cancer Cases Receiving the NP Regimen

Background: Chemotherapy induced leutropenia has been shown to be associated with improved treatmentoutcomes in selected solid tumors. We studied the association of chemotherapy induced leutropenia with treatmentrelated outcomes in advanced non-small-cell lung cancer.
Methods: This is a prospective analysis of patientsreceiving chemotherapy for advanced NSCLC at the Shandong Cancer Hospital from 2005-07.The chemotherapyincluded cisplatin 35 mg/m2, IV on d1,2 and vinorelbine 25 mg/m2 IV on d1,8 every 21 days. Patients were stratifiedinto three groups (A) those experiencing grades 0 leucopenia, group (B) grades 1-2 and group (C) grades 3-4. Theoutcomes studied were response rate (RR), disease control rate (DCR), and time to progression (TTP).
Results:128 patients were studied. The RRs in groups A, B and C were 30.8%, 56.8% and 71.4%, respectively, p=0.010.The DCRs were 61.5%, 83.8% and 92.9%, respectively, p=0.009 and the median TTPs were 150 days (95%CI:91-209), 189 days (95%CI: 181-197) and 207 days (95%CI: 172-242), p=0.009. The differences in RR and TTPwere significant. In patients whose CIL kept on 10 days at least, the TTP was significantly prolonged, p=0.0213,and the same was the case for those experiencing grades 1-2 leucopenia and ECOG 0, p=0.0412.
Conclusions:Occurrence of CIL correlated with RR and TTP in patients with advanced NSCLC receiving cisplatin andvinorelbine chemotherapy, especially in patients experiencing grades 1-2 leucopenia and ECOG 0, and thesame for those with CIL persisting for 10 days at least. CIL could be a biological measure of drug activity anda marker of efficacy.