Dynamics of neutrophil-to-lymphocyte ratio predict outcomes of metastatic colorectal carcinoma patients treated by FOLFOX.

Background: Peripheral blood cell count is the most common clinical laboratory test. Neutrophil-to-lymphocyte ratio (NLR) as an economic marker has been reported in various cancer types. It is believed that NLR is associated with the prognosis and treatment outcomes of some cancers. Low baseline NLR has been reported as associated with better overall survival (OS) in advanced cancer patients. In this study, we aimed to determine whether the changes of NLR may predict the outcome of metastatic colorectal carcinoma (mCRC) patients treated with folinic acid, fluorouracil, and oxaliplatin (FOLFOX) combined with bevacizumab/cetuximab.

Methods: The clinical data obtained from 128 mCRC patients between January 2014 and December 2018 were retrospectively analyzed. The NLR values of patients were calculated after 4 cycles of treatments. Kaplan-Meier analysis and Cox regression modeling were performed to assess the impact of NLR dynamics on OS and progression-free survival (PFS).

Results: Among the 128 participants, the optimum pre-treatment NLR cutoff value was 3. A total of 70 (54.7%) participants had a pre-treatment of NLR lower than 3. The median of PFS was 9.1 months for NLR <3 compared with 6.1 months for pre-treatment NLR >3. A lower pre-treatment NLR was significantly associated with better PFS (P<0.001), but not associated with OS (P=0.064). A total of 94 (73.4%) participants had a post-treatment NLR <3, which was associated with better PFS and OS (P=0.007). However, changes in NLR significantly affected PFS and OS. Decrease in post-treatment NLR was associated with longer PFS and OS. Patients with changes from low pre-treatment NLR to high post-treatment NLR had worse OS and PFS than that of NLR changes from high to low.

Conclusions: It is not the NLR but the changes of NLR that may predict the efficacy of FOLFOX treatment in mCRC patients.