Method of pedicle division during laparoscopic right hemicolectomy affects lymph node yield and short-term outcomes.

BACKGROUND: Several ways of performing laparoscopic right hemicolectomy (RHC) have evolved. The vascular pedicle can be divided into extracorporeal (RHC-EC) or intracorporeal (RHC-IC). It is not known whether vessel ligation during RHC-EC is as central as during RHC-IC. We compare these approaches in terms of pathological and short-term clinical outcomes. METHODS: Patients undergoing elective laparoscopic RHC in a single centre (July 2013-September 2016) were identified. Data collection included operative details, length of stay, complications, specimen parameters including number and involvement of lymph nodes and recurrence. RESULTS: One hundred and sixty-nine patients were included (94 RHC-IC, 75 RHC-EC). For caecal and ascending colon cancers, mesocolic width was greater after RHC-IC than RHC-EC (7.9 cm versus 6.6 cm, P < 0.05), as was lymph node yield (19.5 versus 17.3, P < 0.05). There was no significant difference in length of colon resected, distal resection margin, number of positive nodes, proportion of node-positive tumours and R1 rate. Operative duration was higher for RHC-IC (163 min versus 91 min, P < 0.001), as was incidence of ileus (35% versus 15%, P < 0.05). Length of stay also tended to be higher (7.4 days versus 6.0 days, P = 0.19). There was no difference in disease recurrence (follow-up 12 months). Body mass index was positively correlated with lymph node yield for RHC-EC, but not for RHC-IC. CONCLUSION: Lymph node yield after laparoscopic RHC is adequate, whether the vascular pedicle is taken intracorporeal or extracorporeal, supporting the use of both approaches. RHC-IC yields more lymph nodes and greater mesocolic width, but involves a longer operation and higher incidence of ileus.

Canonical Wnt signals combined with suppressed TGFß/BMP pathways promote renewal of the native human colonic epithelium.

BACKGROUND: A defining characteristic of the human intestinal epithelium is that it is the most rapidly renewing tissue in the body. However, the processes underlying tissue renewal and the mechanisms that govern their coordination have proved difficult to study in the human gut. OBJECTIVE: To investigate the regulation of stem cell-driven tissue renewal by canonical Wnt and TGFß/bone morphogenetic protein (BMP) pathways in the native human colonic epithelium. DESIGN: Intact human colonic crypts were isolated from mucosal tissue samples and placed into 3D culture conditions optimised for steady-state tissue renewal. High affinity mRNA in situ hybridisation and immunohistochemistry were complemented by functional genomic and bioimaging techniques. The effects of signalling pathway modulators on the status of intestinal stem cell biology, crypt cell proliferation, migration, differentiation and shedding were determined. RESULTS: Native human colonic crypts exhibited distinct activation profiles for canonical Wnt, TGFß and BMP pathways. A population of intestinal LGR5/OLFM4-positive stem/progenitor cells were interspersed between goblet-like cells within the crypt-base. Exogenous and crypt cell-autonomous canonical Wnt signals supported homeostatic intestinal stem/progenitor cell proliferation and were antagonised by TGFß or BMP pathway activation. Reduced Wnt stimulation impeded crypt cell proliferation, but crypt cell migration and shedding from the crypt surface were unaffected and resulted in diminished crypts. CONCLUSIONS: Steady-state tissue renewal in the native human colonic epithelium is dependent on canonical Wnt signals combined with suppressed TGFß/BMP pathways. Stem/progenitor cell proliferation is uncoupled from crypt cell migration and shedding, and is required to constantly replenish the crypt cell population.

Sessional GPs: support needed to provide the evidence required for appraisal and revalidation.

BACKGROUND: This study set out to evaluate evidence submitted by GPs for appraisal, and to explore how a model of appraisal can be developed which meets the needs of revalidation while remaining developmental and formative. This paper focuses on comparing evidence submitted by principal and sessional GPs, following previous work demonstrating problems facing the latter group. METHODS: A checklist devised by one author was used by appraisers in one PCT to record evidence submitted for appraisal. This enabled a comparison between 76 principal and 47 sessional GPs of evidence submitted in one appraisal year from April 2008 to March 2009. The evidence was classified as personal or practice based, and the presence of reflection was noted. This quantitative evidence was supplemented by qualitative data from five focus groups with 22 GPs and one appraisal manager, and by interviews with seven GP appraisal leads in PCTs. RESULTS: While some differences were noted between principal and sessional GPs, there were no differences found between the proportion of principal and sessional GPs who submitted personal evidence concerning data collection/audit, significant events, multi-source feedback and complaints. Focus groups indicated reasons and strategies which reflected these findings. CONCLUSIONS: Sessional GPs have already begun to use innovative approaches to ensure they meet the evidence requirements of appraisal and revalidation. However, they are more likely to succeed if they are well supported by educational and practice networks.

Reliability of the Lode Excalibur Sport Ergometer and applicability to Computrainer electromagnetically braked cycling training device.

New technology allows cyclists to train via power output (PO) in addition to heart rate (HR). For those athletes undertaking seasonal laboratory testing (e.g., Vo(2), lactate threshold), it is imperative that athletes be able to directly apply this information to their training device. We examined the reliability of a standardized laboratory ergometer (Lode Excalibur Sport) and its applicability to an electromagnetically braked ergometer (Computrainer) in 2 phases. Phase I (n = 12) examined the reliability of the Lode. Phase II (n = 14) compared the Lode to the Computrainer using a randomized, counterbalance assignment. Following warm-up, each trial started at 100 W, progressing 50 W every 3 minutes to exhaustion. Outcomes were time-to-exhaustion (TTE), peak PO (W) (PO(peak)), peak HR (HR(peak)), and ventilatory (VT) and respiratory compensation (RCP) thresholds. We used a repeated measures analysis of variance (ANOVA), Tukey post hoc analysis, regression analysis, Bland-Altman plots, and coefficient of variation (CV) analysis for each variable. During phase I, we found no significant difference for any variable, minimal dispersion of Vo(2) during Bland-Altman analysis, and a low CV at each test stage (

Clearance of circulating tumor cells after excision of primary colorectal cancer.

OBJECTIVE: To establish whether the prevalence of positive reverse transcriptase-polymerase chain reaction (RT-PCR) results decreased during the first 3 months after colorectal cancer excision, and to assess whether persistence of RT-PCR positivity after primary colorectal cancer excision was related to tumor stage or locally advanced and metastatic disease. METHODS: Systemic venous blood was collected from patients with colorectal cancer before and at intervals up to 12 weeks after surgery. RNA was extracted from the mononuclear cell fraction of the blood samples and subjected to RT-PCR using specific primers for carcinoembryonic antigen mRNA and cytokeratin-20 mRNA. Healthy individuals with no history of cancer were used as controls. RESULTS: The results of RT-PCR were positive in 81 of 116 patients with colorectal cancer before surgery, with no significant differences in preoperative prevalence by Dukes stage or presence of locally advanced or metastatic disease. There was a significant decrease in the prevalence of RT-PCR positivity at 24 hours after surgery compared with before surgery. On subgroup analysis by Dukes stage, only the decrease in Dukes A and B patients reached significance. Seven of the 143 controls were RT-PCR positive. CONCLUSIONS: Circulating tumor cells were present before treatment in most patients with colorectal cancer regardless of tumor stage or metastases. Clearance of circulating tumor cells within 24 hours of colorectal cancer excision was greatest in tumors with the best prognosis.