RE: nab-Paclitaxel Plus Gemcitabine for Metastatic Pancreatic Cancer: Long-Term Survival From a Phase III Trial

We read with interest the article by Goldstein and colleagues that reports the long-term results of the large phase III randomized trial (IMPACT) of nab-paclitaxel plus gemcitabine or gemcitabine alone in patients with metastatic pancreatic cancer, extending support for the superior efficacy of this combination therapy (1).

They reported that the presence of a systemic inflammatory response, as evidenced by an elevated neutrophil lymphocyte ratio (NLR), effectively stratified survival independent of the trial treatment. A pooled treatment analysis demonstrated that patients with an NLR of 5 or less had a statistically significantly prolonged survival compared with patients with an NLR of more than 5 (median = 9.1 vs 5.0 months, P < .001). In the nab-Paclitaxel plus gemcitabine arm there was a statistically significantly longer overall survival vs the gemcitabine arm alone in patients with an NLR of 5 or less (P < .001). Furthermore, when there was evidence of a raised systemic inflammatory response, a trend was evident favoring prolonged survival in the nab-paclitaxel plus gemcitabine arm vs the gemcitabine alone group (P = .079).

These results confirm our previous observations in patients with pancreatic adenocarcinoma, that an elevated NLR is an important independent prognostic factor (2). However, there is good evidence that assessment of the systemic inflammatory response using acute phase proteins, in particular C-reactive protein (CRP) and albumin (Glasgow Prognostic Score [GPS]) has superior prognostic value in a variety of common solid tumors (3), including pancreatic cancer both in resectable and nonresectable forms (2).

Therefore, it is clear that even in such a poor-prognosis tumor as pancreatic cancer outcomes can be stratified according to the systemic inflammatory response. This new knowledge offers the possibility for simple and effective stratification for patients with this difficult-to-treat cancer.

For heterogeneous cancers, in particular pancreatic cancer, a stratified medicine approach offers potential to target an individual’s cancer with the right treatment for the right patient (4). This strategy could improve overall outcomes and quality of life for patients by minimizing unnecessary side effects arising from ineffective therapies. However, as demonstrated in the present study, the concept of stratification should not be limited to tumor- or gene-centric aspects but extended to consider patient or host aspects including the burden of the systemic inflammatory response.

Moreover, beyond stratification there is also an opportunity for therapeutic targeting of the systemic inflammatory response. Given the role of JAK-STAT signaling in the inflammatory responses of patients with pancreatic cancer (5), it is of interest that a recent randomized phase II trial of the JAK1/JAK2 inhibitor ruxolitinib combined with capecitabine in patients with metastatic pancreatic cancer revealed a statistically significantly prolonged survival for those patients who were administered ruxolitinib with coexisting evidence of an elevated systemic inflammatory response, as measured by CRP and/or the modified GPS (6). It is also of interest that nab-paclitaxel itself has potential to alter the tumor stroma and immune environment (7).

In summary, the work of Goldstein and colleagues (1) confirms the prognostic value of the systemic inflammatory response in patients with metastatic pancreatic cancer. Furthermore, it heralds a new era in which the systemic inflammatory response becomes a legitimate target for treatment of these patients.