The Safety and Feasibility of Laparoscopic Surgery for Very Low Rectal Cancer: A Retrospective Analysis Based on a Single Center's Experience.

In this work we intend to validate the long-term oncologic outcomes for very low rectal cancer over the past 20 years and to determine whether laparoscopic procedures are useful options for very low rectal cancer. A total of 327 patients, who electively underwent laparoscopic rectal cancer surgery for a lesion within 5 cm from the anal verge, were enrolled in this study and their long-term outcomes were reviewed retrospectively. Of 327 patients, 70 patients underwent laparoscopic low anterior resection (LAR), 164 underwent laparoscopic abdominal transanal proctosigmoidocolectomy with coloanal anastomosis (LATA), and 93 underwent laparoscopic abdominoperineal resection (APR). The conversion rate was 1.22% (4/327). The overall postoperative morbidity rate was 26.30% (86/327). The 5-year disease free survival (DFS), 5-year overall survival (OS), and 3-year local recurrence (LR) were 64.3%, 79.7%, and 9.2%, respectively. The CRM involvement was a significant independent factor for DFS (p = 0.018) and OS (p = 0.042) in multivariate analysis. Laparoscopic APR showed poorer 5-year DFS (47.8%), 5-year OS (64.0%), and 3-year LR (17.6%) than laparoscopic LAR (74.1%, 86.4%, 1.9%) and laparoscopic LATA (69.2%, 83.6%, 9.2%). Laparoscopic procedures for very low rectal cancer including LAR, LATA, and APR could be good surgical options in selective patients with very low rectal cancer.

Comparison between preoperative and postoperative concurrent chemoradiotherapy for rectal cancer: an institutional analysis.

PURPOSE: To evaluate the treatment outcomes of preoperative versus postoperative concurrent chemoradiotherapy (CRT) on locally advanced rectal cancer. MATERIALS AND METHODS: Medical data of 114 patients with locally advanced rectal cancer treated with CRT preoperatively (54 patients) or postoperatively (60 patients) from June 2003 to April 2011 was analyzed retrospectively. 5-Fluorouracil (5-FU) or a precursor of 5-FU-based concurrent CRT (median, 50.4 Gy) and total mesorectal excision were conducted for all patients. The median follow-up duration was 43 months (range, 16 to 118 months). The primary end point was disease-free survival (DFS). The secondary end points were overall survival (OS), locoregional control, toxicity, and sphincter preservation rate. RESULTS: The 5-year DFS rate was 72.1% and 48.6% for the preoperative and postoperative CRT group, respectively (p = 0.05, the univariate analysis; p = 0.10, the multivariate analysis). The 5-year OS rate was not significantly different between the groups (76.2% vs. 69.0%, p = 0.23). The 5-year locoregional control rate was 85.2% and 84.7% for the preoperative and postoperative CRT groups (p = 0.98). The sphincter preservation rate of low-lying tumor showed significant difference between both groups (58.1% vs. 25.0%, p = 0.02). Pathologic tumor and nodal down-classification occurred after the preoperative CRT (53.7% and 77.8%, both p < 0.001). Acute and chronic toxicities were not significantly different between both groups (p = 0.10 and p = 0.62, respectively). CONCLUSION: The results confirm that preoperative CRT can be advantageous for improving down-classification rate and the sphincter preservation rate of low-lying tumor in rectal cancer.

Preoperative elevation of carcinoembryonic antigen predicts poor tumor response and frequent distant recurrence for patients with rectal cancer who receive preoperative chemoradiotherapy and total mesorectal excision: a multi-institutional analysis in an Asian population.

PURPOSE: This study was conducted to evaluate the significance of carcinoembryonic antigen (CEA) level as a predictor for tumor response to chemoradiotherapy (CRT) and a prognosticator for survival in Asian patients with advanced rectal cancer. MATERIALS AND METHODS: We enrolled 345 patients with primary rectal cancer who had undergone preoperative CRT and total mesorectal excision. We analyzed clinicopathological factors that could be associated with pathologically complete response (ypCR) and disease-free survival (DFS). RESULTS: A cutoff level of 5 ng/mL (p = 0.002) for CEA was found to be significant for prediction of ypCR. Increased CEA level (p = 0.025) was a significant negative predictor of ypCR after CRT in patients with rectal cancer. The 5-year DFS rate was significantly higher in the CEA ≤5-ng/mL group than in the CEA >5-ng/mL group (73.2 vs. 60.9 %, p = 0.002). This is mainly due to the higher chance of distant recurrence (p = 0.013), not locoregional recurrence (p = 0.732), in the CEA >5-ng/mL group. CONCLUSIONS: Elevated CEA (>5 ng/mL) is a negative predictor of ypCR and has a negative impact on DFS in Asian rectal cancer patients who underwent preoperative CRT and surgery due to an increased chance of distant recurrences.

Transanal endoscopic microsurgery for the treatment of well-differentiated rectal neuroendocrine tumors.

PURPOSE: Recently, an increase in well-differentiated rectal neuroendocrine tumors (WRNETs) has been noted. We aimed to evaluate transanal endoscopic microsurgery (TEM) for the treatment of WRNETs. METHODS: Between December 1995 and August 2009, 109 patients with WRNETs underwent TEM. TEM was performed for patients with tumors sizes of up to 20 mm and without a lymphadenopathy. These patients had been referred from other clinics after having been diagnosed with WRNETs by using a colonoscopic biopsy; they had undergone a failed endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) and exhibited an involved resection margin and remaining tumor after ESD or EMR, regardless of the distance from the anal verge. This study included 38 patients that had more than three years of follow-up. RESULTS: The mean age of the patients was 51.3 ± 11.9 years, the mean tumor size was 8.0 ± 3.9 mm, and no morbidity occurred. Thirty-five patients were asymptomatic. TEM was performed after a colonoscopic resection in 13 cases because of a positive resection margin, a residual tumor or a non-lifting lesion. Complete resections were performed in 37 patients; one patient with a positive margin was considered surgically complete. In one patient, liver metastasis and a recurrent mesorectal node occurred after five and 10 years, respectively. CONCLUSION: TEM might provide an accessible and effective treatment either as an initial or as an adjunct after a colonoscopic resection for a WRNET.

Relationship between TYMS and ERCC1 mRNA expression and in vitro chemosensitivity in colorectal cancer.

AIM: The aim of this study was to determine whether the relative mRNA expressions of the thymidylate synthase (TYMS) and the excision repair cross-complementing 1 (ERCC1) genes are associated with in vitro chemosensitivity to 5-fluorouracil (5-FU) and oxaliplatin in colorectal cancer, respectively. PATIENTS AND METHODS: This study included 67 patients with pathologic TNM stage II, III, and IV. TYMS and ERCC1 mRNA expression was determined using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The chemosensitivity was examined using an ATP-based chemotherapy response assay. A high response was defined as a response producing ≥40% reduction in ATP. RESULTS: The mean level of TYMS mRNA expression in the groups with low and high response to 5-FU was 2.35×10(-3) ± 2.16×10(-3) 2(-(ΔCt)) and 4.54×10(-3) ± 2.46×10(-3) 2(-(ΔCt)), respectively. The mean level of ERCC1 mRNA expression in the groups with low and high response to oxaliplatin was 13.92×10(-3) ± 9.90×10(-3) 2(-(ΔCt)) and 23.59×10(-3) ± 5.88×10(-3) 2(-(ΔCt)), respectively. Groups with high response to 5-FU and oxaliplatin had significantly higher expression of TYMS and ERCC1 mRNA, respectively (p<0.01 and p=0.01, respectively). CONCLUSION: High expression of TYMS and ERCC1 mRNA was associated with better in vitro chemosensitivity to 5-FU and oxaliplatin, respectively, in patients with colorectal cancer.