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

Abstract

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.

Keywords::

• biomarker
• circulating tumor cell
• CTC
• diagnostic
• locally advanced cancer
• pancreatic ductal adenocarcinoma
• PDAC

Financial and competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Circulating tumor cells (CTCs) have not been previously assessed in locally advanced pancreatic cancer (LAPC).

• • CTCs were detectable in 11% of LAPC patients and led to a poorer overall survival (OS), but not progression-free survival (PFS).

• • All methods used for CTC detection have limitations and it is unclear if detected CTCs have malignant potential.

• • Other studies have found patients with detectable CTCs to have poorer OS and PFS; however, these patients had more advanced and metastatic pancreatic ductal adenocarcinoma.

• • The low statistical power of this study affects the conclusions.

• • Using CTCs as a prognostic marker in LAPC needs further investigation.