Aim: To compare intracorporeal anastomosis (IA) and extracorporeal anastomosis (EA) in laparoscopic right colectomy (LRC) in terms of intraoperative and postoperative outcomes. Methods: A systematic literature search with no limits was performed in PubMed and Embase. The last search was performed on April 9, 2016. The outcomes of interests included intraoperative outcomes (operative time, blood loss, length of incision, conversion, lymph nodes harvested, and intraoperative complications) and postoperative outcomes (time to first flatus, time to first defecation, time to liquid diet, length of hospital stay, postoperative complications, mortality, ileus, anastomotic leakage, anastomotic bleeding, wound infection, hernia, and intra-abdominal abscess). Results: Fifteen articles and four conference abstracts published between 2004 and 2016 with a total of 1957 patients were enrolled in this meta-analysis. IA was associated with significant less blood loss, smaller length of incision, shorter time to first defecation, shorter time to liquid diet, and shorter length of hospital stay. No differences were found for operative time, conversion, lymph nodes harvested, intraoperative complications, time to first flatus, postoperative complications, mortality, anastomotic leakage, anastomotic bleeding, ileus, wound infection, intra-abdominal abscess, or hernia between IA and EA. Conclusion: Our meta-analysis suggests that the IA for LRC improves cosmesis and results in better postoperative recovery outcomes without increasing intraoperative and postoperative complications. Furthermore, a large randomized control study is warranted to compare the short-term and long-term outcomes of those two anastomosis techniques.

Objective: To compare neoadjuvant chemotherapy (nCT) with CAPOX alone versus neoadjuvant chemoradiotherapy (nCRT) with capecitabine in locally advanced rectal cancer (LARC) with uninvolved mesorectal fascia (MRF). Background Data: nCRT is associated with higher surgical complications, worse long-term functional outcomes, and questionable survival benefits. Comparatively, nCT alone seems a promising alternative treatment in lower-risk LARC patients with uninvolved MRF. Methods: Patients between June 2014 and October 2020 with LARC within 12 cm from the anal verge and uninvolved MRF were randomly assigned to nCT group with 4 cycles of CAPOX (Oxaliplatin 130 mg/m2 IV day 1 and Capecitabine 1000 mg/m2 twice daily for 14 d. Repeat every 3 wk) or nCRT group with Capecitabine 825 mg/m² twice daily administered orally and concurrently with radiation therapy (50 Gy/25 fractions) for 5 days per week. The primary end point is local-regional recurrence-free survival. Here we reported the results of secondary end points: histopathologic response, surgical events, and toxicity. Results: Of the 663 initially enrolled patients, 589 received the allocated treatment (nCT, n=300; nCRT, n=289). Pathologic complete response rate was 11.0% (95% CI, 7.8-15.3%) in the nCT arm and 13.8% (95% CI, 10.1-18.5%) in the nCRT arm (P=0.33). The downstaging (ypStage 0 to 1) rate was 40.8% (95% CI, 35.1-46.7%) in the nCT arm and 45.6% (95% CI, 39.7-51.7%) in the nCRT arm (P=0.27). nCT was associated with lower perioperative distant metastases rate (0.7% vs. 3.1%, P=0.03) and preventive ileostomy rate (52.2% vs. 63.6%, P=0.008) compared with nCRT. Four patients in the nCT arm received salvage nCRT because of local disease progression after nCT. Two patients in the nCT arm and 5 in the nCRT arm achieved complete clinical response and were treated with a nonsurgical approach. Similar results were observed in subgroup analysis. Conclusions: nCT achieved similar pCR and downstaging rates with lower incidence of perioperative distant metastasis and preventive ileostomy compared with nCRT. CAPOX could be an effective alternative to neoadjuvant therapy in LARC with uninvolved MRF. Long-term follow-up is needed to confirm these results.

Exosomes or other extracellular vesicles released from cells play an important role in cell-to-cell communication by transferring bio-information (DNA, coding/non-coding RNA, and proteins), which indicates parental cell status to recipient cells in the extracellular environment. Increasingly, evidence shows that tumor-derived exosomes mediate tumor pre-metastatic niche (PMN) remodeling to establish a supportive and receptive niche to promote tumor cell colonization and metastasis. Uptake of genetic information by target cells in the extracellular environment triggers epigenetic changes that contribute to PMN formation. Here, we provide a comprehensive overview of the current understanding of exosomes-mediated reprogramming of cells in PMN formation.

Background: Magnetic resonance imaging (MRI)-based lymph node staging remains a significant challenge in the treatment of rectal cancer. Pretreatment evaluation of lymph node metastasis guides the formulation of treatment plans. This systematic review aimed to evaluate the diagnostic performance of MRI in lymph node staging using various morphological criteria.Methods: A systematic search of the EMBASE, Medline, and Cochrane databases was performed. Original articles published between 2000 and January 2021 that used MRI for lymph node staging in rectal cancer were eligible. The included studies were assessed using the QUADAS-2 tool. A bivariate random-effects model was used to conduct a meta-analysis of diagnostic test accuracy.Results: Thirty-seven studies were eligible for this meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio of preoperative MRI for the lymph node stage were 0.73 (95% confidence interval [CI], 0.68–0.77), 0.74 (95% CI, 0.68–0.80), and 7.85 (95% CI, 5.78–10.66), respectively. Criteria for positive mesorectal lymph node metastasis included (A) a short-axis diameter of 5 mm, (B) morphological standard, including an irregular border and mixed-signal intensity within the lymph node, (C) a short-axis diameter of 5 mm with the morphological standard, (D) a short-axis diameter of 8 mm with the morphological standard, and (E) a short-axis diameter of 10 mm with the morphological standard. The pooled sensitivity/specificity for these criteria were 75%/64%, 81%/67%, 74%/79%, 72%/66%, and 62%/91%, respectively. There was no significant difference among the criteria in sensitivity/specificity. The area under the receiver operating characteristic (ROC) curve values of the fitted summary ROC indicated a diagnostic accuracy rate of 0.75–0.81.Conclusion: MRI scans have minimal accuracy as a reference index for pretreatment staging of various lymph node staging criteria in rectal cancer. Multiple types of evidence should be used in clinical decision-making.

Although previous meta-analyses have proved that lymphocyte-to-monocyte ratio (LMR) is a prognostic factor in solid cancers, its prognostic role in colorectal cancer (CRC) remains controversial. We, therefore, conducted this up-to-date meta-analysis to evaluate the prognostic role of the LMR in CRC. A systematic search was performed in PubMed and Embase for relevant studies in November 2016. Article assessing the prognostic role of LMR in CRC was enrolled in this meta-analysis. Data and characteristics of each study were extracted. A meta-analysis was performed to generate pooled hazard ratio (HR) and 95% confidence intervals (95% CIs) for overall survival (OS) and disease-free survival. Begg funnel plot was used to evaluate publication bias. Eleven studies published between 2014 and 2016 with a total of 9045 patients were enrolled in this meta-analysis. Our findings indicated that a low LMR predicted a worse OS (HR 1.57, 95% CI 1.30–1.90, P < .001) and disease-free survival. (HR 1.25, 95% CI 1.13–1.39, P < .001) for patients with CRC. Subgroup analyses according to stage (I–III and IV) and LMR cut-off value (<3.00 and ≥3.00) showed a significant prognostic value of LMR on OS. Begg funnel plot showed that publication bias existed in this meta-analysis. This up-to-date meta-analysis shows that a low LMR is associated with poor survival in patients with CRC, although the publication bias is existed. Large-sample multicenter prospective cohort is needed to assess the role of the LMR in CRC patients.

PURPOSE: Complete mesocolic excision (CME) is being increasingly used for the treatment of right-sided colon cancer, although there is still no strong evidence that CME provides better long-term oncological outcomes than D2 dissection. The controversy is mainly regarding the survival benefit from extended lymph node dissection emphasized by CME. METHODS: This multicenter, open-label, randomized controlled trial (ClinicalTrials.gov identifier: NCT02619942 ) was performed across 17 hospitals in China. Patients diagnosed with stage T2-T4aNanyM0 or TanyN + M0 right-sided colon cancer were randomly assigned (1:1) to undergo either CME or D2 dissection during laparoscopic right colectomy. The primary outcome was the 3-year disease-free survival (DFS), and the main secondary outcome was the 3-year overall survival (OS). RESULTS: Between January 11, 2016, and December 26, 2019, 1,072 patients were randomly assigned (536 patients to CME and 536 patients to D2 dissection). In total, 995 patients (median age 61 years, 59% male) were included in the primary analysis (CME [n = 495] v D2 dissection [n = 500]). No significant differences were found between the groups in 3-year DFS (hazard ratio [HR], 0.74 [95% CI, 0.54 to 1.02]; P = .06; 86.1% in the CME group v 81.9% in the D2 group) or in 3-year OS (HR, 0.70 [95% CI, 0.43 to 1.16]; P = .17; 94.7% in the CME group v 92.6% in the D2 group). CONCLUSION: This trial failed to find evidence of superior DFS outcome for CME compared with standard D2 lymph node dissection in primary surgical excision of right-sided colon cancer. Standard D2 dissection should be the routine procedure for these patients. CME should only be considered in patients with obvious mesocolic lymph node involvement.