京都大学 / 新制・課程博士 / 博士(医学) / 甲第25168号 / 医博第5054号 / 京都大学大学院医学研究科医学専攻 / (主査)教授 上野 英樹, 教授 波多野 悦朗, 教授 伊藤 能永 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Objective: We aimed to assess the prognostic value of circulating tumor cells (CTC) in patients with advanced gastric and gastroesophageal adenocarcinomas. Methods: The presence of CTC was evaluated in 62 patients with advanced gastric and gastroesophageal adenocarcinomas before systemic therapy and at follow-up through immunomagnetic enrichment for mucin 1- and epithelial cell adhesion molecule (EpCAM)-positive cells, followed by real-time RT-PCR of the tumor-associated genes KRT19 , MUC1 , EPCAM , CEACAM5 and BIRC5 . Results: The patients were stratified into groups according to CTC detection (CTC negative: with all marker genes negative; CTC positive: with at least 1 of the marker genes positive). Patients who were CTC positive at baseline had a significantly shorter median progression-free survival (PFS; 3.5 months, 95% CI: 2.9–4.2) and overall survival (OS; 5.8 months, 95% CI: 4.5–7.0) than patients lacking CTC (PFS 10.7 months, 95% CI: 6.9–14.4, p < 0.001; OS 13.3 months, 95% CI: 8.0–18.6, p = 0.003). Alterations in the marker profile during the course of chemotherapy were not predictive of clinical outcome or response to therapy. Yet, a favorable clinical response depended significantly on CTC negativity (p = 0.03). Conclusion: Our data suggest that the presence of CTC is a major predictor of outcome in patients with gastric and gastroesophageal malignancies.