Clinical utility of circulating tumor cells: an update

The prognostic role of circulating tumor cells (CTCs) has been clearly demonstrated in many types of cancer. However, their roles in diagnostic and treatment strategies remain to be defined. In this review, we present an overview of the current clinical validity of CTCs in nonmetastatic and metastatic cancer, and the main studies or concepts investigating the clinical utility of CTCs. In particular, we focus on breast, lung, colorectal, and prostate cancer. Two major topics concerning the clinical utility of CTC are discussed: treatment based on CTC count or CTC variations, and treatment based on the molecular characteristics of CTCs. Although some of these studies are inconclusive, many are still ongoing, and their results could help to define the role of CTCs in the management of cancers. A summary of published or ongoing phase II-III trials is also presented.

Automated summary

The prognostic role of circulating tumor cells (CTCs) has been well established in various types of cancer, but their definitive role in diagnostic and treatment strategies is still to be defined. Current clinical research on CTCs focuses mainly on breast, lung, colorectal, and prostate cancer. Studies are primarily exploring treatment approaches based on CTC count or variations, as well as treatment based on the molecular characteristics of CTCs.