BackgroundThe epidermal growth factor receptor (EGFR)/RAS/RAF/MEK/MAPK pathway is an important pathway in the carcinogenesis, invasion and metastasis of colorectal cancers (CRCs). We conducted a retrospective study to determine the prognostic values of EGFR expression and KRAS mutation in patients with metastatic CRC (mCRC) based on synchronous or metachronous status.MethodsFrom October 2002 to March 2012, 205 patients with mCRC were retrospectively analyzed; 98 were found to have metachronous mCRC while 107 were found to have synchronous mCRC. The EGFR expressions were determinate by IHC (immunohistochemistry) analysis and categorized 1+ (weak intensity), 2+ (moderate intensity), and 3+ (strong intensity). Genomic DNA was isolated from frozen primary CRC tissues and direct sequencing of KRAS was performed. The clinicopathological features of these mCRC patients were retrospectively investigated according to EGFR expression and KRAS mutation status. Moreover, we analyzed the prognostic values of EGFR expression and KRAS mutation among these patients.ResultsOf the 205 patients with mCRC, EGFR expression was analyzed in 167 patients, and positive EGFR expression was noted in 140 of those patients (83.8%). KRAS mutation was investigated in 205 patients and mutations were noted in 88 of those patients (42.9%). In patients with metachronous mCRC, positive EGFR expression was significantly correlated with well-and moderately-differentiated tumors (P = 0.028), poorer disease-free survival (DFS) (P < 0.001), and overall survival (OS) (P < 0.001). Furthermore, positive EGFR expression was a significant independent prognostic factor of DFS (P = 0.006, HR: 4.012, 95% CI: 1.130–8.445) and OS (P = 0.028, HR: 3.090, 95% CI: 1.477–10.900) in metachronous mCRC patients. KRAS mutation status was not significantly related to DFS and OS of patients with metachronous mCRC; likewise, KRAS mutation status was not significantly different in the progression-free survival (PFS) and OS of patients with synchronous mCRC (all P > 0.05).ConclusionsThe present study demonstrated that EGFR expression has prognostic value only for patients with metachronous mCRC. However, KRAS mutation did not have prognostic value in patients with metachronous or synchronous mCRC.

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BackgroundAfter a low anterior resection, creating a defunctioning stoma is vital for securing the anastomosis in low-lying rectal cancer patients receiving concurrent chemoradiotherapy. Although it decreases the complication and reoperation rates associated with anastomotic leakage, the complications that arise before and after stoma closure should be carefully evaluated and managed.MethodsThis study enrolled 95 rectal cancer patients who received neoadjuvant concurrent chemoradiotherapy and low anterior resection with anastomosis of the bowel between July 2010 and November 2012. A defunctioning stoma was created in 63 patients during low anterior resection and in another three patients after anastomotic leakage.ResultsThe total complication rate from stoma creation to closure was 36.4%. Ileostomy led to greater renal insufficiency than colostomy did and significantly increased the readmission rate (all p < 0.05). The complication rate related to stoma closure was 36.0%. Patients with ileostomy had an increased risk of developing complications (p = 0.017), and early closure of the defunctioning stoma yielded a higher incidence of morbidity (p = 0.006). Multivariate analysis revealed that a time to closure of ≤109 days was an independent risk factor for developing complications (p = 0.007).ConclusionsThe optimal timing of stoma reversal is at least 109 days after stoma construction in rectal cancer patients receiving concurrent chemoradiotherapy and low anterior resection.

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ERCC1 overexpression is an important predictor of early failure in patients with stage III CRC administrating FOLFOX-4 adjuvant chemotherapy and this marker may help identify patients who would benefit from intensive follow-up and enhance therapeutic programs.

In consideration of the better ypT0-2 downstaging rate, less severe toxicities, and no need for indwelling intravenous device on oral capecitabine regimen, the administration of oral capecitabine with RT may be a more favorable option in the neoadjuvant treatment for LARC.

BackgroundWe present our preliminary experiences and results for forty consecutive patients with colorectal cancer (CRC) who were treated by robotic surgery.MethodsBetween May 2013 and September 2014, forty patients with CRC received robotic surgery at a single institution. The clinicopathological features and perioperative parameters were retrospectively analyzed.ResultsOf the 40 patients with CRC, 33 (82.5 %) had rectal cancers, and 22 (66.7 %) of those 33 patients also underwent pre-operative concurrent chemoradiotherapy (CCRT). The two most frequent surgical procedures were intersphincteric resection (ISR) with coloanal anastomosis (16/40, 40 %) and lower anterior resection (LAR) (15/40, 37.5 %). Among all 40 patients, the median time to first flatus passage was 2 days. The median time to soft diet resumption was 4 days. The median post operative hospital stay was 7 days. The overall complication rate was 20 % (8/40 patients), of which most of the complications were mild, although one laparotomy was required to check for post-operative bleeding. There was no 30-day hospital mortality, nor conversion to open surgery and laparoscopy.ConclusionWe present our preliminary experiences of robotic colorectal surgery and demonstrate that robotic colorectal surgery is a safe and feasible surgery even when conducted by laparoscopic surgeons with limited experience.

Colorectal cancer (CRC) is a major public health problem. Early CRC detection, pretherapeutic responsiveness prediction, and postoperative micrometastasis monitoring are the hallmarks for successful CRC treatment. Here, the methodologies used for detecting circulating tumor cells (CTCs) from CRC are reviewed. In addition to the traditional CRC biomarkers, the persistent presence of posttherapeutic CTCs indicates resistance to adjuvant chemotherapy and/or radiotherapy; hence, CTCs also play a decisive role in the subsequent relapse of CRC. Moreover, the genetic and phenotypic profiling of CTCs often differs from that of the primary tumor; this difference can be used to select the most effective targeted therapy. Consequently, studying CTCs can potentially individualize treatment strategies for patients with CRC. Therefore, CTC detection and characterization may be valuable tools for refining prognosis, and CTCs can be used in a real-time tumor biopsy for designing individually tailored therapy against CRC.