Dynamic monitoring of circulating tumour cells to evaluate therapeutic efficacy in advanced gastric cancer

TLDR

Elevated circulating tumour cells during therapy are linked to poorer prognosis in advanced gastric cancer, and post‑therapy CTC levels may aid in assessing therapeutic response and predicting outcomes. This study aimed to evaluate the clinical significance of circulating tumour cells for dynamic monitoring of therapeutic response in patients with advanced gastric cancer. In a single‑centre prospective cohort of 136 newly diagnosed advanced gastric cancer patients, CTCs were quantified with the CellSearch system at baseline and at the first response assessment. Among 15 patients with longitudinal data, a post‑therapy CTC count of ≥3 per 7.5 ml was associated with lower objective response and disease‑control rates, independently predicted shorter progression‑free and overall survival, and conversion to a favorable CTC level improved prognosis, indicating that CTC dynamics can rapidly identify ineffective treatments and poor outcomes.

Abstract

This study was intended to determine the clinical significance of circulating tumour cells (CTCs) in patients with advanced gastric cancer (AGC), particularly the potential role of CTCs for dynamic monitoring of the therapeutic response.A single-centre, prospective study was undertaken in 136 patients with newly diagnosed AGC. The patients' CTCs were enumerated using CellSearch at baseline and at the first response evaluation. In 15 patients whose clinical condition permitted longitudinal study, CTCs were longitudinally enumerated during treatment.Following 6 weeks of chemotherapy, an unfavourable post-therapy CTC level (⩾3 CTCs per 7.5 ml) was closely correlated with the objective response rate (P=0.016) and the disease control rate (P=0.013), and it also independently predicted a shorter progression-free survival and overall survival. Particularly, conversion to a favourable CTC level following therapy improved the prognosis, but patients who changed to an unfavourable CTC level fared significantly worse. Elevated CTCs during therapy may be associated with a poor prognosis.Post-therapy CTC level may help in evaluating therapeutic response in patients with AGC and predicting their prognosis. In addition, changes in CTCs following therapy may be useful in rapidly identifying ineffective treatments and poor prognosis.