Clinical Potential of Circulating Tumor Cells in Colorectal Cancer: A Prospective Study.

OBJECTIVES: Circulating tumor cells (CTCs) in the blood have been used as diagnostic markers in patients with colorectal cancer (CRC). In this study, we evaluated a CTC detection system based on cell size to assess CTCs and their potential as early diagnostic and prognostic biomarkers for CRC. METHODS: From 2014 to 2015, 88 patients with newly diagnosed CRC, who were scheduled for surgery, and 31 healthy volunteers were enrolled and followed up in Pusan National University Hospital. CTCs were enriched using a centrifugal microfluidic system with a new fluid-assisted separation technique (FAST) and detected by cytomorphological evaluation using fluorescence microscopy. RESULTS: Two or more CTCs were detected using FAST in 74 patients and 3 healthy volunteers. The number of CTCs in the CRC group was significantly higher than that in the healthy volunteers (P < 0.001). When a receiver operating characteristic curve was created to differentiate patients with CRC from healthy volunteers, the sensitivity and specificity were almost optimized when the critical CTC value was 5/7.5 mL of blood. When this value was used, the sensitivity and specificity in differentiating patients with CRC from the healthy controls were 75% and 100%, respectively. In patients with CRC with ≥5 CTCs, vascular invasion was frequently identified (P = 0.035). All patients with stage IV were positive for CTCs. Patients with ≥5 CTCs showed a trend toward poor overall and progression-free survival. DISCUSSION: Our study demonstrated promising results with the use of FAST-based CTC detection for the early diagnosis and prognosis of CRC.

Case of Bleeding Ileal Varices after a Colectomy Diagnosed by Capsule Endoscopy.

We report a case of bleeding ileal varices associated with intra-abdominal adhesions after colectomy which was successfully diagnosed using capsule endoscopy. A 77-year-old woman visited the emergency department for several episodes of melena. She had a medical history of neoadjuvant chemo-radiation therapy and subsequent surgery for rectal cancer 6 years previously. Conventional diagnostic examinations including upper endoscopy, colonoscopy, and abdominal computed tomography could not detect any bleeding focus, however, following capsule endoscopy revealed venous dilatations with some fresh blood in the distal ileum, indicating bleeding ileal varices. The patient underwent exploratory laparotomy and the affected ileum was successfully resected. No further gastrointestinal bleeding occurred during the 6 months follow-up. Small intestinal varices are important differential for obscure gastrointestinal bleeding especially in patients with a history of abdominal surgery in the absence of liver cirrhosis, and capsule endoscopy can be a good option for diagnosing small intestinal varices.