Is the detection of circulating tumor cells in locally advanced pancreatic cancer a useful prognostic marker?

Evaluation of: Bidard FC, Huguet F, Louvet C et al. Circulating tumor cells in locally advanced pancreatic adenocarcinoma: the ancillary CirCe 07 study to the LAP 07 trial. Ann. Oncol. 24(8), 2057–2061 (2013). Circulating tumor cells (CTCs) may be shed from the primary tumor and lead to metastatic disease. This evaluated article reports on CTCs in locally advanced pancreatic cancer (LAPC). By assessing CTCs from peripheral blood prior to any treatment and after 2 months of chemotherapy, 11% of patients had detectable CTCs. These patients had a poorer overall survival. With such low numbers of CTCs detected in LAPC patients, it is unclear whether CTCs can actually contribute toward tumor invasiveness and spread in such an aggressive cancer. Although this is a well-designed study, the small number of patients with detectable CTCs means that the statistical power is not great enough to make firm conclusions. Therefore, this expensive assay needs further investigation before being used a prognostic marker in patients with LAPC.