Genome-wide CNV analysis reveals candidate genes associated with milk production traits in water buffalo (Bubalus bubalis).

Buffaloes are vital contributors to the global dairy industry. Understanding the genetic basis of milk production traits in buffalo populations is essential for breeding programs and improving productivity. In this study, we conducted whole-genome resequencing on 387 buffalo genomes from 29 diverse Asian breeds, including 132 river buffaloes, 129 swamp buffaloes, and 126 crossbred buffaloes. We identified 36,548 copy number variant (CNVs) spanning 133.29 Mb of the buffalo genome, resulting in 2,100 copy number variant regions (CNVRs), with 1,993 shared CNVRs being found within the studied buffalo types. Analyzing CNVRs highlighted distinct genetic differentiation between river and swamp buffalo subspecies, verified by evolutionary tree and principal component analyses. Admixture analysis grouped buffaloes into river and swamp categories, with crossbred buffaloes displaying mixed ancestry. To identify candidate genes associated with milk production traits, we employed 3 approaches. First, we used Vst-based population differentiation, revealing 11 genes within CNVRs that exhibited significant divergence between different buffalo breeds, including genes linked to milk production traits. Second, expression quantitative loci (eQTL) analysis revealed differential expression of CNVR-driven genes (DECGs) associated with milk production traits. Notably, known milk production-related genes were among these DECGs, validating their relevance. Last, a genome-wide association study (GWAS) identified 3 CNVRs significantly linked to peak milk yield. Our study provides comprehensive genomic insights into buffalo populations and identifies candidate genes associated with milk production traits. These findings facilitate genetic breeding programs aimed at increasing milk yield and improving quality in this economically important livestock species.

Novel Insight into the Potential Role of Acylglycerophosphate Acyltransferases Family Members on Triacylglycerols Synthesis in Buffalo.

Acylglycerophosphate acyltransferases (AGPATs) are the rate-limiting enzymes for the de novo pathway of triacylglycerols (TAG) synthesis. Although AGPATs have been extensively explored by evolution, expression and functional studies, little is known on functional characterization of how many members of the AGPAT family are involved in TAG synthesis and their impact on the cell proliferation and apoptosis. Here, 13 AGPAT genes in buffalo were identified, of which 12 AGPAT gene pairs were orthologous between buffalo and cattle. Comparative transcriptomic analysis and real-time quantitative reverse transcription PCR (qRT-PCR) further showed that both AGPAT1 and AGPAT6 were highly expressed in milk samples of buffalo and cattle during lactation. Knockdown of AGPAT1 or AGPAT6 significantly decreased the TAG content of buffalo mammary epithelial cells (BuMECs) and bovine mammary epithelial cells (BoMECs) by regulating lipogenic gene expression (p < 0.05). Knockdown of AGPAT1 or AGPAT6 inhibited proliferation and apoptosis of BuMECs through the expression of marker genes associated with the proliferation and apoptosis (p < 0.05). Our data confirmed that both AGPAT1 and AGPAT6 could regulate TAG synthesis and growth of mammary epithelial cells in buffalo. These findings will have important implications for understanding the role of the AGPAT gene in buffalo milk performance.

A nomogram for predicting rectovaginal fistula after low anterior resection for rectal cancer.

PURPOSE: Rectovaginal fistula (RVF) is a complicated and troublesome complication of low anterior resection (LAR) for rectal cancer. We aimed to investigate the risk factors for post-LAR RVF and develop a predictive nomogram. METHODS: We performed a retrospective analysis of 821 female patients with rectal cancer who underwent LAR between October 2010 and October 2018. Logistic regression was performed to identify risk factors. A nomogram was developed to predict RVF. RESULTS: The incidence of post-LAR RVF was 3.4% (28/821). A multivariate analysis showed that the preoperative serum hemoglobin level (OR 2.449, 95% CI 1.144-5.239), the distance between the tumor and anal verge (OR 4.158, 95% CI 1.392-12.418), surgical procedure (OR 2.369, 95% CI 1.117-5.027), hysterectomy (OR 2.996, 95% CI 1.106-8.833), and bilateral oophorectomy (OR 5.823, 95% CI 1.639-20.689) were significantly associated with the development of RVF. A nomogram was developed, which showed a C-index of 0.824 (95% CI 0.730-0.918) and an adjusted C-index of 0.790. CONCLUSION: This study identified the preoperative serum hemoglobin level, the distance between the tumor and the anal verge, the type of surgical procedure, hysterectomy, and bilateral oophorectomy as predictors of post-LAR RVF. A nomogram was successfully developed. It could aid in the prediction of RVF in patients undergoing LAR.

Risk Factors for Early Postoperative Small Bowel Obstruction after Elective Colon Cancer Surgery: An Observational Study of 1,244 Consecutive Patients.

BACKGROUND: Early postoperative small bowel obstruction (EPSBO) is a common complication following colon cancer surgery. EPSBO is associated with increased hospital stays, mortality rates, and healthcare costs. The purpose of this study was to identify risk factors for EPSBO following elective colon cancer surgery. STUDY DESIGN: We retrospectively reviewed the clinicopathological variables of 1,244 patients with colon cancer who underwent partial colectomy from January 2000 to December 2014. A multivariable logistic regression model was used to identify risk factors for EPSBO. RESULTS: The EPSBO rate was 3.5%. In multivariate analysis, preoperative bowel obstruction (OR 2.378; 95% CI 0.986-5.735, p = 0.054), weight loss >10% of body weight (OR 3.029; 95% CI 1.000-9.178, p = 0.05), albumin level (in g/L; OR 0.966; 95% CI 0.937-0.996, p = 0.024), and surgical duration (in min; OR 1.008; 95% CI 1.003-1.012, p = 0.003) were significant predictors of EPSBO. CONCLUSION: EPSBO is more likely to develop in the presence of poor systemic conditions (e.g., weight loss >10% of body weight, hypoalbuminemia, and preoperative bowel obstruction) and following operations of longer duration. These predictors may facilitate the stratification of patients at risk for EPSBO following surgery for elective colon cancer.

Laparoscopic transabdominal approach partial intersphincteric resection for low rectal cancer: surgical feasibility and intermediate-term outcome.

BACKGROUND: Traditionally, conventional intersphincteric resection requires a combined abdominal and perineal approach and a handsewn coloanal anastomosis procedure, which is difficult to accomplish via the perineal approach. A completely abdominal approach partial intersphincteric resection (APISR) with laparoscopy can simplify the anastomosis procedure. This study evaluated the intermediate-term oncological and functional results of laparoscopic versus open APISR for low rectal cancer. METHODS: A total of 137 consecutive patients with low rectal cancer who underwent APISR from January 2006 to August 2013 were retrospectively evaluated. Patient groups were classified into as open surgery (OP, n = 48) group and laparoscopy (LAP, n = 89). The primary endpoint was 3-year disease-free survival and the Wexner score for anal function. RESULTS: The LAP group had longer operating time, less intraoperative blood loss, and shorter hospital stay after surgery compared with the OP group. Median follow-up was 32.3 months. The local recurrence rates were similar in the two groups (LAP 3.2% vs. OP 6.1%; P = 0.652). The combined 3-year disease-free survival rate was 83.2% in the LAP group and 83.8% in the OP group (P = 0.857). Wexner scores were similar in the two groups (LAP 2.9 ± 4.5 vs. OP 3.1 ± 5.0). In the LAP group, 89.7% of patients had good continence compared with 91.4% in the OP group (P = 0.311). CONCLUSIONS: Laparoscopic APISR can be performed safely and offers similar intermediate-term oncological and functional outcome compared with the open procedure. The oncological adequacy requires long-term follow-up data.

A scoring system to predict inferior mesenteric artery lymph node metastasis and prognostic value of its involvement in rectal cancer.

PURPOSE: The aim of this study is to establish a prediction scoring system for inferior mesenteric artery (IMA) lymph node metastasis and to assess the prognostic impact of dissection of positive IMA node on patients with stage III rectal cancer. METHODS: A retrospective study was performed in 264 patients with stage III rectal cancer undergoing curative surgery. Clinicopathological, survival, and recurrence data were compared between 29 patients with positive IMA nodes and 235 patients with negative IMA nodes. Clinicopathological data which were found to be significantly associated with IMA nodal status were incorporated into a scoring system. RESULTS: In the training samples, tumor differentiation and preoperative serum CEA were significant predictors of IMA node metastasis in multivariate analysis, which were incorporated into a scoring system. Using receiver operating characteristic curve analysis, we determined a cutoff value of 46.5 for scores, at which the system's sensitivity was 86 % and specificity 61 %. When applied to testing sample, the sensitivity was 80 % and specificity 60 %. Survival analysis showed that 5-year disease-free survival rate (5-DFS) and 5-year overall survival (5-OS) in the positive IMA node group (24.4 and 27.6 %, respectively) were significantly lower than in the negative IMA node group (61.8 and 71.3 %, respectively) (P < 0.001). Furthermore, multivariate analysis indicated that IMA lymph node metastasis was an unfavorable independent prognostic factor for 5-DFS and 5-OS. CONCLUSIONS: IMA lymph node metastasis is an independent poor prognostic factor for stage III rectal cancer. The prediction scoring system for IMA node metastasis would be beneficial in determining the appropriate level of IMA ligation.

Laparoscopic extralevator abdominoperineal resection for rectal carcinoma with transabdominal levator transection.

BACKGROUND: The extralevator abdominoperineal resection (ELAPR) is a new surgical technique for patients with low advanced rectal cancer. This technique requires an extra excision of the levator muscles to avoid the surgical waist caused by the conventional abdominoperineal resection, with the patient's position changed to a prone jackknife position and using a myocutaneous flap to repair the pelvic defect. To simplify this operation, we applied a laparoscopic technique to perform controlled transabdominal transection of the levator muscles under direct visualization without a position change and pelvic floor reconstruction using human acellular dermal matrix (HADM). METHODS: In our department from 2010-2011, six patients with rectal adenocarcinoma within 3 cm of the anal verge underwent laparoscopic ELAPR with transabdominal levator transection, with no position change during the perineal operation. In three patients, pelvic reconstruction was performed with HADM. RESULTS: All procedures were successfully performed without any intraoperative complications, laparoscopy-associated morbidity, or conversion to the open approach. The mean operation time and intraoperative blood loss were 186.7 min and 101.7 ml. All specimens had a cylindrical shape with levator muscles attached to the mesorectum and negative circumferential margins. No complications were seen with the use of HADM. CONCLUSIONS: Laparoscopic transabdominal transection of the levator muscles without position change and with pelvic floor reconstruction using human acellular dermal matrix mesh is feasible. With the transection of the levator muscles under laparoscopic surveillance, the procedure of the extralevator abdominoperineal resection, which is aggressively invasive and operatively complicated, is simplified and has an advantage of minimal invasiveness.

Hartmann reversal: obesity adversely impacts outcome.

BACKGROUND: Comprehensive analyses are lacking to identify predictors of postoperative complications in patients who undergo a Hartmann reversal. OBJECTIVE: The aim of this study is to identify predictive factors for morbidity after reversal. DESIGN: This study is a retrospective review of prospectively collected data. SETTINGS: The study was conducted at Cleveland Clinic Florida. PATIENTS: Consecutive patients from January 2004 to July 2011 who underwent reversal were included. MAIN OUTCOME MEASURES: Variables pertaining to Hartmann procedure and reversal were obtained for analyses in patients with and without postoperative complications. Univariate and multivariate analyses were performed. RESULTS: A total of 95 patients (mean age 61 years, 56% male) underwent reversal, with an overall morbidity of 46%. Patients with and without complications had similar demographics, comorbidities, diagnoses, and Hartmann procedure intraoperative findings. Patients with complications after reversal were more likely to have prophylactic ureteral stents (61% vs 41%, p < 0.05) and an open approach (91% vs 75%, p < 0.04). Complications were associated with longer hospital stay (8.8 vs 6.9 days,p < 0.006) and higher rates of reintervention (9% vs 0%, p < 0.03) and readmission (16% vs 2%, p < 0.02). Predictors of morbidity after reversal included BMI (29 vs 26 kg/m, p < 0.04), hospital stay for Hartmann procedure (15 vs 10 days, p < 0.03), and short distal stump (50% vs 31%, p < 0.05). BMI was the only independent predictor of morbidity (p < 0.04). Obesity was associated with significantly greater overall morbidity (64% vs 40%, p < 0.04), wound infections (56% vs 31%, p < 0.04), diverting ileostomy at reversal (24% vs 13%, p < 0.05), and time between procedures (399 vs 269 days, p < 0.02). LIMITATIONS: This study was limited by its retrospective design. CONCLUSIONS: Hartmann reversal is associated with significant morbidity; BMI independently predicts complications. Therefore, patients who are obese should be encouraged or even potentially required to lose weight before reversal.

Apelin and Apelin Receptor in Follicular Granulosa Cells of Buffalo Ovaries: Expression and Regulation of Steroidogenesis.

Apelin (APLN), as a ligand for APJ (an orphan G-protein-coupled receptor), is an adipokine with pleiotropic effects in many physiological processes of the body. It has an important role in the control of reproduction particularly in females (mainly in control of ovarian function). This study was carried out to investigate the mRNA and protein amounts of APLN/APJ in granulose cells (GCs) of ovarian follicles with small (SF), medium (MF), and large (LF) sizes of buffalo (Bubalus bubalis) and the effect of IGF1 and follicle-stimulating hormone (FSH) on the expression levels of APLN/APJ. In addition, we evaluated the effect of various doses of APLN (isoforms -13 and -17) singly or in combination with IGF1 and FSH on estradiol (E2) and progesterone (P4) secretion in GCs. The mRNA and protein abundance of APLN was the highest in GCs of LF while the APJ expression enhanced with follicle enlargement in GCs (p-value <0.01). IGF1 and FSH elevated the mRNA and protein amounts of APLN and FSH, and IGF1 increased the expression of APJ in buffalo GCs (p-value <0.01). Both isoforms of APLN (-13/-17) singly or in the presence of IGF1 or FSH increased the secretion of E2 and P4 with or without preincubation of cells with APJ antagonist (ML221 10 µM), although we had some variation in the effects. Concurrently, APLN-13/-17 significantly increased the mRNA and protein expression of CYP19A1 and StAR (p-value <0.01). ML221 substantially diminished the secretion of E2 and P4 and also the expression of CY19A1 and StAR in buffalo GCs (p-value <0.01). We also revealed that APLN-13/-17 (10-9 M), singly or in response to IGF1 and FSH, increased the production of E2 and P4 in different times of stimulation. In conclusion, APLN may play a crucial role in steroidogenesis and follicular development in ovarian GCs of buffalo.

Global transcriptome analysis of different stages of preimplantation embryo development in river buffalo.

BACKGROUND: Water buffalo (Bubalus bubalis) are divided into river buffalo and swamp buffalo subspecies and are essential livestock for agriculture and the local economy. Studies on buffalo reproduction have primarily focused on optimal fertility and embryonic mortality. There is currently limited knowledge on buffalo embryonic development, especially during the preimplantation period. Assembly of the river buffalo genome offers a reference for omics studies and facilitates transcriptomic analysis of preimplantation embryo development (PED). METHODS: We revealed transcriptomic profile of four stages (2-cell, 8-cell, Morula and Blastocyst) of PED via RNA-seq (Illumina HiSeq4000). Each stage comprised three biological replicates. The data were analyzed according to the basic RNA-seq analysis process. Ingenuity analysis of cell lineage control, especially transcription factor (TF) regulatory networks, was also performed. RESULTS: A total of 21,519 expressed genes and 67,298 transcripts were predicted from approximately 81.94 Gb of raw data. Analysis of transcriptome-wide expression, gene coexpression networks, and differentially expressed genes (DEGs) allowed for the characterization of gene-specific expression levels and relationships for each stage. The expression patterns of TFs, such as POU5F1, TEAD4, CDX4 and GATAs, were elucidated across diverse time series; most TF expression levels were increased during the blastocyst stage, during which time cell differentiation is initiated. All of these TFs were involved in the composition of the regulatory networks that precisely specify cell fate. These findings offer a deeper understanding of PED at the transcriptional level in the river buffalo.

Survival outcome of adjuvant radiotherapy after local excision for T2 early rectal cancer: An analysis based on the surveillance, epidemiology, and end result registry database.

BACKGROUND: Major resection (MR) is recommended for cases with T2 finding after local excision (LE) of early rectal cancer, but the revision procedure is accompanied with high morbidity. We evaluated the oncological safety of LE followed by adjuvant radiotherapy as a rectum-preserving alternative to MR for T2 early rectal cancer. METHODS: A total of 3786 patients with T2N0M0 rectal adenocarcinoma between 1998 and 2013 were included from the SEER database. Survival rates were compared using the Kaplan-Meier method with a log-rank test, and multivariate analyses were performed using Cox proportional regression models. RESULTS: Of these patients included, 429 (11.3%) treated with LE alone (LE group), 3067 (81.0%) treated with MR (MR group), and 290 (7.7%) treated with LE followed by adjuvant radiotherapy (LE + adjuvant RT group). The 5-year cancer specific survival (CSS) rate and 5-year overall survival (OS) rate were significantly lower in LE patients group than those in MR patients group (70.5% vs. 81.8%, P < 0.001; 57.3% vs. 72.3%, P < 0.001). The 5-year CSS rate and 5-year OS rate were similar between LE + adjuvant RT and MR groups (78.4% vs. 81.8%, P = 0.975, and 70.7% vs. 72.3%, P = 0.311, respectively). Multivariate Cox regression revealed that treatment strategies, age and CEA status were independently associated with CSS and OS. After age adjustment, LE was associated with reduced CSS (using MR as a reference, HR, 1.784; P < 0.001) and reduced OS (HR, 1.739; P < 0.001). However, CSS and OS related to LE + adjuvant RT of T2 rectal cancer group weren't be affected (HR, 0.994; P = 0.962 and HR, 0.904; P = 0.302, respectively). CONCLUSIONS: When MR is inappropriate for T2 early rectal cancer patients because of patients refusal or co-morbidities, LE + adjuvant RT can provide acceptable levels of long-term survival.

Effect of Neoadjuvant Chemoradiotherapy on Locally Advanced Rectal Mucinous Adenocarcinoma: A Propensity Score-Matched Study.

Aims. To compare the surgical and oncological outcomes of rectal mucinous adenocarcinomas treated with neoadjuvant chemoradiotherapy versus surgery alone. Methods. A total of 167 locally advanced rectal mucinous adenocarcinoma patients treated with neoadjuvant chemoradiotherapy and surgery alone between 2008 and 2014 were matched using propensity score; the surgical and oncological outcomes were compared. Results. Ninety-six patients were matched. Postoperative morbidity was similar between groups. Sphincter preservation rate was higher in patients receiving neoadjuvant chemoradiotherapy (79.2% versus 60.4%, P = 0.045), especially for tumors ≥ 3 cm but ≤5 cm from the anal verge (75.0% versus 44.0%, P = 0.036). With a median follow-up of 54.8 months, the 5-year overall survival rate (neoadjuvant chemoradiotherapy versus surgery alone: 79.6% versus 67.1%; P = 0.599) and disease-free survival rate (75.6% versus 64.2%; P = 0.888) were similar. The 5-year local recurrence rate was lower in patients receiving neoadjuvant chemoradiotherapy (7.7% versus 26.0%, P = 0.036), while no difference was observed in distant metastasis. A poor response to chemoradiation was associated with higher local recurrence (P = 0.037). Conclusions. Compared with surgery alone, neoadjuvant chemoradiotherapy was found to increase the sphincter preservation rate and reduce local recurrence, thus being beneficial for locally advanced rectal mucinous adenocarcinoma patients.

Effect of Interval between Neoadjuvant Chemoradiotherapy and Surgery on Oncological Outcome for Rectal Cancer: A Systematic Review and Meta-Analysis.

Aim. To evaluate the influence of interval between neoadjuvant chemoradiotherapy (NCRT) and surgery on oncological outcome. Methods. A systematic search was conducted in PubMed, the Cochrane Library, and Embase databases for publications reporting oncological outcomes of patients following rectal cancer surgery performed at different NCRT-surgery intervals. Relative risk (RR) of pathological complete response (pCR) among different intervals was pooled. Results. Fifteen retrospective cohort studies representing 4431 patients met the inclusion criteria. There was a significantly increased rate of pCR in patients treated with surgery followed 7 or 8 weeks later (RR, 1.45; 95% CI, 1.18-1.78; and P < 0.01 and RR, 1.49; 95% CI, 1.15-1.92; and P = 0.002, resp.). There is no consistent evidence of improved local control or overall survival with longer or shorter intervals. Conclusion. Performing surgery 7-8 weeks after the end of NCRT results in the highest chance of achieving pCR. For candidates of abdominoperineal resection before NCRT, these data support implementation of prolonging the interval after NCRT to optimize the chances of pCR and perhaps add to the possibility of ultimate organ preservation.

A scoring system basing pathological parameters to predict regional lymph node metastasis after preoperative chemoradiotherapy for locally advanced rectal cancer: implication for local excision.

Local excision is an alternative to radical surgery that is indicated in patients with locally advanced rectal cancer (LARC) who have a good response to chemoradiotherapy (CRT). Regional lymph node status is a major uncertainty during local excision of LARC following CRT. We retrospectively reviewed clinicopathologic variables for 244 patients with LARC who were treated at our institute between December 2000 and December 2013 in order to identify independent predictors of regional lymph node metastasis. Multivariate analysis of the training sample demonstrated that histopathologic type, tumor size, and the presence of lymphovascular invasion were significant predictors of regional nodal metastasis. These variables were then incorporated into a scoring system in which the total scores were calculated based on the points assigned for each parameter. The area under the curve in the receiver operating characteristic analysis was 0.750, and the cutoff value for the total score to predict regional nodal metastasis was 7.5. The sensitivity of our system was 73.2% and the specificity was 69.4%. The sensitivity was 77.8% and the specificity was 51.2% when the scoring system was applied to the testing sample. Using this system, we could accurately predict regional nodal metastases in LARC patients following CRT, which may be useful for stratifying patients in clinical trials and selecting potential candidates for organ-sparing surgery following CRT for LARC.

Comparison of chemical, electrical, and combined activation methods for in vitro matured porcine oocytes.

Factors influencing porcine oocyte activation were systematically studied. This study included (1) the effect of ionomycin plus various chemical agents on activation, (2) comparison of different electrical activation parameters, (3) optimization of combined activation, and (4) evaluation of the optimized protocols. The results showed that (1) blastocyst rates of ionomycin (Ion) + 6-dimethylaminopurine (6-DMAP) (29.7 ± 1.1%), Ion + cytochalasin B (CB) + cycloheximide (CHX) (29.8 ± 1.2%), Ion + CB + 6-DMAP (30.4 ± 1.6%), and Ion + CB + CHX + 6-DMAP (30.2 ± 2.7%) were significantly higher than Ion + CHX (15.8 ± 1.5%, p < 0.05); (2) the parthenogenetic blastocyst formation of electrical activation was optimal when oocytes were activated by three direct current (DC) pulses of 1.00 kV cm(-1) for 80 µs (39.5 ± 1.1%); (3) blastocyst rates of DC + CB + CHX (55.4 ± 1.2%) and DC + CB + 6-DMAP (50.4 ± 2.9%) were significantly higher than DC + 6-DMAP, DC + CB + CHX + 6-DMAP, electrical activation, and chemical activation alone (p < 0.05); and (4) approximately 84% of parthenogenetic blastocysts yielded by the optimized protocol were diploid, which was significantly higher than that of electrical activation blastocysts (40%). Using the optimized electrical and combined activation protocol, high blastocyst rates were generated by intracytoplasmic sperm injection (ICSI) (34.6 ± 1.1%), cytoplasmic microinjection (CI) (52.3 ± 2.2%), and handmade cloning (HMC) (31.2 ± 1.0%), respectively. This study concludes that the optimal activation protocol of in vitro matured porcine oocytes was combined activation with parameter as three DC pulses of 1.00 kV cm(-1) for 80 µs plus CB and CHX treatment.

[Laparoscopic cylindrical abdominoperineal resection with transabdominal approach for lower rectal cancer].

OBJECTIVE: To evaluate the safety and feasibility of laparoscopic cylindrical abdominoperineal resection. METHODS: Six patients with rectal adenocarcinoma within 3 cm above the anal verge underwent laparoscopic cylindrical abdominoperineal resection. Transabdominal levator transaction was performed laparoscopically, with no position change during the perineal operation. Pelvic reconstruction was achieved using human acellular dermal matrix mesh in 3 patients. RESULTS: All the procedures were successfully performed without any intraoperative complications, laparoscopy-associated complications, or conversion to the open approach. The mean operation time was 186.7 minutes and intraoperative blood loss was 101.7 ml. All the specimens had a cylindrical shape with levator muscles attached to the mesorectum and circumferential margins were all negative. No adverse incidence followed the pelvic reconstruction using human acellular dermal matrix mesh. CONCLUSIONS: Laparoscopic transabdominal transection of the levator muscles without position change and pelvic floor reconstruction with human acellular dermal matrix mesh is feasible. This procedure simplifies cylindrical abdominoperineal resection which is aggressively invasive and technically complicated. The oncologic outcomes are acceptable and complications are less.

[Comparison of efficacy between laparoscopic versus open complete mesocolic excision for colon cancer].

OBJECTIVE: To explore the differences in long-term outcomes between laparoscopic and open complete mesocolic excision(CME) for colon cancer. METHODS: A total of 273 patients with colon cancer who underwent CME at the Fujian Medical University Union Hospital from September 2000 to December 2008 were divided into laparoscopic(LP, n=147) and open(OP, n=126) groups in a non-random manner. The oncologic and long-term outcomes were compared. RESULTS: No significant differences were seen in the length of distal and proximal margin, and number of lymph nodes(all P>0.05). Median postoperative follow up was 50 months. Local regional recurrence rates (LP 6.1% vs. OP 7.9%) and distal metastasis rates(LP 23.8% vs. OP 16.7%) were similar between the two groups(all P>0.05). The 5-year overall survival rates (LP 69.4% vs. OP 74.0%, P=0.840) and 5-year disease-free survival rates(LP 68.5% vs. OP 70.9%, P=0.668) between the two groups were not statistically different. CONCLUSIONS: Laparoscopic CME has the same oncologic clearance effects compared with open CME for colon cancer. It might become a new standardized surgery for colon cancer.

[Risk factors of postoperative chyle leak following complete mesocolic excision for colon cancer].

OBJECTIVE: To investigate the incidence, risk factors and preventative methods associated with chyle leak following complete mesocolic excision(CME) for colon cancer. METHODS: Clinical data of 592 patients with colon cancer undergoing CME in the department of Colorectal Surgery in the Fujian Medical University Union Hospital from September 2000 to September 2011 were analyzed retrospectively. RESULTS: Chyle leak occurred in 46 patients(7.7%). The incidence of postoperative chyle leak following right CME hemicolectomy was 13.3%(30/226), significantly higher than that after left CME hemicolectomy (4.4%). On univariate analysis, chyle leak following CME was associated with tumor size(P<0.05), tumor location(P<0.01), and lymph nodes harvested(P<0.01). Multivariate logistic regression revealed that tumor location and lymph nodes harvested were independent risk factors associated with chyle leak following CME(P<0.05). CONCLUSIONS: Tumor location and lymph nodes harvested are independent risk factors for chyle leak following complete mesocolic excision for colon cancer. When the drainage output suddenly increases after oral intake resumption, the chyle test of ascitic fluid should be performed for early diagnosis and prompt management.

[Treatment of chyle leak following radical resection for colorectal cancer].

OBJECTIVE: To investigate the treatment of chyle leak following radical resection for colorectal cancer. METHODS: The incidence of chyle leak was compared between the different surgical approaches (open vs. laparoscopic) as well as different tumor locations (right, left colon or rectum) in 1259 patients undergoing radical resection for colorectal cancer. RESULTS: Overall incidence of chyle leak was 3.6% (46/1259) after surgery. Forty-five patients were successfully managed by conservative treatment and one patient required re-operation. No patients died. The incidence of chyle leak was not significantly different between the open (3.2%, 18/570) and laparoscopic (4.1%, 28/689) groups (P>0.05). However, right colectomy was associated with a significantly higher rate of chyle leak (9.6%, 16/167) as compared to left colectomy(2.6%, 7/268) and anterior resection (2.8%, 23/824) (P<0.05). CONCLUSIONS: Conservative treatment is effective in early stage of chyle leak after radical resection for colorectal cancer. Right colectomy is associated with higher risk for chyle leak.