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Purpose: Although minimally invasive colorectal surgery has been proven to have a shorter hospital stay and fewer short-term complications than open surgery, the advantages of laparoscopic surgery for colorectal cancer patients undergoing hemodialysis have not been validated. This study compared the outcomes of open and laparoscopic approaches in these patients. Materials and methods: Between January 2007 and December 2020, we retrospectively analyzed the clinical data of 78 hemodialysis patients who underwent curative-intent, elective colorectal surgery. Patients were divided into two groups according to the surgical method: open and laparoscopic. Results: Postoperative morbidity (p = 0.480) and mortality (p = 0.598) rates and length of hospital stay (28.8 vs. 27.5 days, p = 0.830) were similar between the groups. However, laparoscopic surgery patients had a shorter return to clear liquid, full liquid, or soft food time than open surgery patients (p < 0.001, p = 0.007, and p = 0.002, respectively). Disease-free survival and long-term cancer-specific survival rates were also similar between the two groups (p = 0.353 and p = 0.201, respectively). Multivariate analysis revealed that intraoperative blood transfusion was a risk factor for severe complications and mortality (OR 6.055; p = 0.046), and the odds ratio (OR) of laparoscopic surgery was not significantly greater than that of open surgery (OR = 0.537, p = 0.337). Conclusion: Although laparoscopic surgery did not result in hemodialysis patients having a shorter postoperative hospital stay, our results suggest that the laparoscopic approach is as safe as open surgery for hemodialysis patients and may be beneficial for shortening the return time to food intake. [ABSTRACT FROM AUTHOR]

Purpose: The optimal timing of stoma closure during or after adjuvant chemotherapy for rectal cancer patients undergoing sphincter-preserving surgery remains unknown. This study aimed to investigate the influence of clinical and oncological outcomes depending on the timing of stoma closure. Methods: Between January 2006 and December 2015, we enrolled 244 consecutive rectal cancer patients who underwent curative-intent sphincter-preserving surgery with diverting transverse colostomy and adjuvant chemotherapy. Patients with stoma closure during (During group) adjuvant chemotherapy were compared to those who had stoma closure after adjuvant chemotherapy (After group). Results: Parastomal hernia occurred more frequently in the after group than in the during group. (10% vs. 2.9%, p = 0.028). Overall, no significant difference was observed in overall survival (OS) or disease-free survival (DFS) between the two groups (p = 0.911 for OS, p = 0.505 for DFS). However, an inferior OS occurred if reopen surgery was performed within 30 days of stoma closure in the during group, as compared with the after group (p = 0.004). In addition, a marginally poor DFS was observed in the group of patients who received further operations due to 30-day stoma closure complications compared to the other patients (p = 0.07). Conclusions: For rectal cancer patients who underwent sphincter-preserving surgery, attention should be given to avoid 30-day major complications after stoma reversal because patients who require reoperation during adjuvant chemotherapy may have poor long-term survival. [ABSTRACT FROM AUTHOR]

Purpose: The standard initial treatment for metastatic colorectal cancer (mCRC) remains debated. This study investigated whether upfront primary tumor resection (PTR) or upfront systemic therapy (ST) provides better survival outcomes for patients with mCRC. Methods: The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched for studies published at any time from January 1, 2004, to December 31, 2022. Randomized controlled trials (RCTs) and prospective or retrospective cohort studies (RCSs) utilizing propensity score matching (PSM) or inverse probability treatment weighting (IPTW) were included. We evaluated overall survival (OS) and short-term (60-day) mortality in these studies. Results: After reviewing 3,626 articles, we identified 10 studies including a total of 48,696 patients. OS differed significantly between the upfront PTR and upfront ST arms (hazard ratio [HR] 0.62; 95% CI: 0.57–0.68; p < 0.001). However, a subgroup analysis identified no significant difference in OS in RCTs (HR 0.97; 95% CI: 0.7–1.34; p = 0.83), whereas significant difference in OS occurred between the treatment arms in RCSs with PSM or IPTW (HR 0.59; 95% CI: 0.54–0.64; p < 0.001). Short-term mortality was analyzed in three RCTs, and 60-day mortality differed significantly between the treatment arms (risk ratio [RR] 3.52; 95% CI: 1.23–10.10; p = 0.02). Conclusions: In RCTs, upfront PTR for mCRC did not improve OS and enhanced the risk of 60-day mortality. However, upfront PTR seemed to increase OS in RCSs with PSM or IPTW. Therefore, whether upfront PTR should be used for mCRC remains unclear. Further large RCTs are required. [ABSTRACT FROM AUTHOR]

Background: Although a temporary stoma can mitigate the severity of anastomotic leakage, some rectal cancer patients retain a permanent stoma after sphincter-preserving surgery. Therefore, this study aimed to identify independent preoperative risk factors for permanent stoma and establish a prediction model for mid-and low-rectal cancer patients who underwent sphincter-preserving surgery and temporary stoma. Methods: We retrospectively reviewed consecutive patients with non-metastatic rectal cancer between 2000 and 2015. The risk factors for permanent stomas were collected and analyzed. Results: A total of 1020 rectal cancer patients with temporary stoma were included. The overall rate of permanent stoma was 17.5% (n = 179). Cancer progression and anastomotic complications are major causes of permanent stomas. Multivariate analysis showed that preoperative risk factors such as advanced age, male sex, preoperative CEA ≥ 10 ng/ml, T4 stage, N stage, low rectal tumor, and ASA ≥ III were independent preoperative risk factors after adjustment. The ROC curve of the risk factors and permanent stoma showed an AUC of 0.689, a cut-off value of 2.5, a sensitivity of 0.689, and a specificity of 0.622. The permanent stoma rates were significantly higher between risk scores ≤ 2 and > 2 (29.9% vs. 11.3%, p < 0.001). Conclusion: Preoperative CEA ≥ 10 ng/ml, T4 stage, N stage, low rectal tumor, advanced age, ASA ≥ III, and male sex were independent preoperative prognostic factors for a permanent stoma. The risk was higher with a score greater than two. Therefore, the risk of subsequent permanent stoma should be evaluated and informed to the patient prior to the primary surgery. [ABSTRACT FROM AUTHOR]

Purpose: Molecular composition of circulating small extracellular vesicles (EVs) does not merely reflect the cells of origin, but also is enriched in specific biomolecules directly associated with the cellular transformation. However, while most of the currently identified EV-miRs are only geared towards one-dimensional disease detection, their application for long-term tracking and treatment response monitoring has been largely elusive. Methods: We established and optimized a rapid, sensitive and robust liquid biopsy sampling method, and further used small RNA sequencing to comprehensively catalogue EV-miRomes in association with the progression and outcome of metastatic colorectal cancer (mCRC). Results: By cross-comparison of EV-miRomes (n = 290) from multi-stage and longitudinal cohorts, we uncovered a 15-EV-miR signature with dual detection and long-term monitoring of tumor size progression for mCRC. From this panel, EV-miR-320c was uncovered as a strong clinical marker – aside from its diagnostic power and a therapeutic monitoring performance superior to carcinoembryonic antigen (CEA), its high expression has also been linked to lower overall survival and a greater likelihood of disease recurrence. Further, integrative analyses of tissue transcriptomic and liquid biopsy implicated this 15-EV-miR signature in programming the mesenchymal–epithelial transition (MET) for distant localization of the metastasized cells and also in creating a tumor-favoring metastatic niche. Conclusion: Our clinically-oriented delineation of the mCRC-associated circulating EV-miRomes systematically revealed the functional significance of these liquid biopsy markers and further strengthen their translational potential in mCRC therapeutic monitoring. [ABSTRACT FROM AUTHOR]

Purpose: Although cigarette smoking is a well-known risk factor for anastomotic leakage during rectal surgery, the proper duration of smoking cessation that can decrease anastomotic leakage in patients undergoing sphincter-preserving surgery is unclear. This study aimed to investigate the optimal duration of smoking cessation that can reduce this complication. Methods: Between January 1, 2000, and December 31, 2012, we enrolled 1246 consecutive patients who underwent curative-intent sphincter-preserving surgery without preventive stoma at the Division of Colorectal Surgery of a tertiary referral center in Taiwan. Questionnaires were used to record their pre-surgical smoking status. The receiver operating characteristic (ROC) curve was used to determine the optimal cut-off duration of smoking cessation. Multivariate analysis was used to verify the effect of cigarette cessation on anastomotic leakage. Results: The ROC curve showed a cut-off value of 10.5 years of cessation duration. Therefore, the former-smoker group was further divided using a cessation duration of 10 years. The overall anastomotic leakage rate was 5.29%. However, the anastomotic leakage rate in current smokers (9.3%) and in those who quit for < 10 years (12.9%) was significantly higher than that in non-smokers (3.3%) and those who quit for ≥ 10 years (4.5%). On multivariate analysis, current smokers (p = 0.022), former smokers with < 10 years of smoking cessation (OR 2.725; p = 0.029), male sex (p = 0.015), and low rectal cancer (p < 0.001) were all independently related to the development of anastomotic leakage. Conclusion: Smoking cessation for < 10 years remains a risk factor for anastomotic leakage in patients with mid-to-low rectal cancer undergoing sphincter-preserving surgery. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. While both genetic and environmental factors have been linked to the incidence and mortality associated with CRC, an ethnic aspect of its etiology has also emerged. Since previous large-scale cancer genomics studies are mostly based on samples of European ancestry, the patterns of clinical events and associated mechanisms in other minority ethnic patients suffering from CRC are largely unexplored. We collected 104 paired and adjacent normal tissue and CRC tumor samples from Taiwanese patients and employed an integrated approach – paired expression profiles of mRNAs and microRNAs (miRNAs) combined with transcriptome-wide network analyses – to catalog the molecular signatures of this regional cohort. On the basis of this dataset, which is the largest ever reported for this type of systems analysis, we made the following key discoveries: (1) In comparison to the The Cancer Genome Atlas (TCGA) data, the Taiwanese CRC tumors show similar perturbations in expressed genes but a distinct enrichment in metastasis-associated pathways. (2) Recurrent as well as novel CRC-associated gene fusions were identified based on the sequencing data. (3) Cancer subtype classification using existing tools reveals a comparable distribution of tumor subtypes between Taiwanese cohort and TCGA datasets; however, this similarity in molecular attributes did not translate into the predicted subtype-related clinical outcomes (i.e., death event). (4) To further elucidate the molecular basis of CRC prognosis, we developed a new stratification strategy based on miRNA–mRNA-associated subtyping (MMAS) and consequently showed that repressed WNT signaling activity is associated with poor prognosis in Taiwanese CRC. In summary, our findings of distinct, hitherto unreported biosignatures underscore the heterogeneity of CRC tumorigenesis, support our hypothesis of an ethnic basis of disease, and provide prospects for translational medicine. [ABSTRACT FROM AUTHOR]

Introduction: Comprehensive genetic cancer profiling using circulating tumor DNA has enabled the detection of National Comprehensive Cancer Network (NCCN) guideline-recommended somatic alterations from a single, non-invasive blood draw. However, reliably detecting somatic variants at low variant allele fractions (VAFs) remains a challenge for next-generation sequencing (NGS)-based tests. We have developed the single-molecule sequencing (SMSEQ) platform to address these challenges. Methods: The OncoLBx assay utilizes the SMSEQ platform to optimize cell-free DNA extraction and library preparation with variant type-specific calling algorithms to improve sensitivity and specificity. OncoLBx is a pan-cancer panel for solid tumors targeting 75 genes and five microsatellite sites analyzing five classes of NCCN-recommended somatic variants: single-nucleotide variants (SNVs), insertions and deletions (indels), copy number variants (CNVs), fusions and microsatellite instability (MSI). Circulating DNA was extracted from plasma, followed by library preparation using SMSEQ. Analytical validation was performed according to recently published American College of Medical Genetics and Genomics (ACMG)/Association for Molecular Pathology (AMP) guidelines and established the limit of detection (LOD), sensitivity, specificity, accuracy and reproducibility using 126 gold-standard reference samples, healthy donor samples verified by whole-exome sequencing by an external College of American Pathologists (CAP) reference lab and cell lines with known variants. Results were analyzed using a locus-specific modeling algorithm. Results: We have demonstrated that OncoLBx detects VAFs of ≥ 0.1% for SNVs and indels, ≥ 0.5% for fusions, ≥ 4.5 copies for CNVs and ≥ 2% for MSI, with all variant types having specificity ≥ 99.999%. Diagnostic performance of paired samples displays 80% sensitivity and > 99.999% clinical specificity. Clinical utility and performance were assessed in 416 solid tumor samples. Variants were detected in 79% of samples, for which 87.34% of positive samples had available targeted therapy. [ABSTRACT FROM AUTHOR]

Background: Preoperative carcinoembryonic antigen (CEA) has yet to be used as a prognostic or adjuvant chemotherapy factor for colorectal cancer (CRC). Methods: This retrospective cohort study included all stage I–III CRC patients with different preoperative serum CEA levels (≤ 5, 5–10, and > 10 ng/ml) at a single center between 1995 and 2010. Propensity score matching was performed in a 1:1 ratio between the two elevated CEA groups (5–10 ng/ml and > 10 ng/ml) and in a 1:2 ratio between the elevated and non-elevated groups (≤ 5 ng/ml), with a caliper of 0.05. Results: After exclusion and matching, 3857 patients had preoperative CEA levels ≤ 5 ng/ml, 1121 patients had CEA levels between 5 and 10 ng/ml, and 1121 patients had CEA levels > 10 ng/ml. Elevated preoperative CEA showed an increased risk of overall survival (5–10 ng/ml: hazard ratio [HR] 1.376; > 10 ng/ml: HR 1.523; both p < 0.001), cancer-specific survival (5–10 ng/ml: HR 1.404; > 10 ng/ml: HR 1.712; both p < 0.001), and recurrence free interval (5–10 ng/ml: HR 1.190; > 10 ng/ml: HR 1.468; both p < 0.05). Patients with negative lymph node staging (LNs) and CEA > 10 ng/ml, as well as those with positive LNs and CEA ≤ 5 ng/ml, showed similar overall survival (5-year survival: 72% vs. 69%; p = 0.542) and recurrence free intervals (19.9 vs. 21.72 months; p = 0.662). Conclusions: A preoperative CEA level can be an independent prognostic factor for stage I–III CRC after curative resection. Patients with negative LNs and preoperative CEA level > 10 ng/ml should be considered for intensive follow-up or adjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Purpose: The rate of postoperative morbidity and mortality is reportedly high in patients aged ≥ 75 years with colorectal cancer (CRC). In such patients, a comparison of the short-term outcome between open method and laparoscopy has not been clearly defined in Taiwan. We aimed to compare postoperative morbidity and mortality parameters after open method and laparoscopy in CRC patients aged ≥ 75 years.Methods: We retrospectively analyzed patients who underwent surgery for CRC from February 2009 to September 2015 at the Linkou Chang Gung Memorial Hospital in Taiwan and analyzed their clinicopathological factors. Postoperative morbidity and mortality were analyzed for evaluating if laparoscopic surgery offers more favorable outcomes than open surgery in the elderly.Results: A total of 1133 patients were enrolled and analyzed in this study; they were divided into two groups (open method vs. laparoscopy = 797 vs. 336). The anastomotic leakage rate was significantly higher in the laparoscopy group than in the open method group (3.3 vs. 0.9%, p = 0.003). Overall postoperative morbidity and mortality rates showed no significant difference between these two groups. Postoperative hospital stay was significantly shorter in the laparoscopy group than in the open method group (10.4 ± 8.7 vs. 13.8 ± 13.5 days, p < 0.001).Conclusions: Our results suggest that laparoscopy in patients aged ≥ 75 years with CRC had higher anastomosis leakage rate compared with open surgery but is acceptable and offers the benefit of a shorter hospital stay over open surgery. [ABSTRACT FROM AUTHOR]

Background: This retrospective study evaluated the prognostic factors of chemotherapy in stage III colorectal cancer after curative resection. Methods: From 1996 to 2001, 1,054 patients with primary single colorectal cancer underwent curative resection. Seven hundred sixteen patients received various 5-fluorouracil (FU)-based adjuvant chemotherapy regimens, including oral and intravenous treatments. The chemotherapy-related parameters examined included therapeutic duration, frequency, route of administration, composition of combination therapies, and postoperative time interval from the operation to the start of chemotherapy. Results: The therapeutic duration and postoperative time interval of starting therapy were independent prognostic factors, in addition to clinicopathological factors. The 8-year cancer-specific/overall survival rates in patients who received chemotherapy for >4 months (63.0/58.6%) were significantly higher than the rates in patients who received no chemotherapy (56.7/37.7%, P < 0.01) and those who remained on chemotherapy for 1-4 months (49.4/41.9%, P < 0.05). The 8-year cancer-specific/overall survival rates in patients who waited 1-5 weeks after surgery to receive chemotherapy (62.9/58.5%) were significantly higher versus rates in those who did not receive chemotherapy (56.7/37.7%) and those who did not receive chemotherapy until >5 weeks after surgery (52.3/45.9%) (both P < 0.05). Survival rates did not differ between patients who did not undergo chemotherapy, those for whom chemotherapy lasted 1-4 months, and patients who did not receive chemotherapy until >5 weeks after surgery. Conclusions: The appropriate duration of therapy and early chemotherapy after surgery were 2 of the most important factors in eradicating occult cancer and effecting long-term survival benefits in patients with stage III colorectal cancer. [ABSTRACT FROM AUTHOR]

Background: Local excision has become an alternative for radical resection in rectal cancer for selected patients. The purpose of this study was to assess the clinicopathologic factors determining lymph node metastasis (LNM) in patients with T1-2 rectal cancer. Methods: Between January 1995 and December 2009, a total of 943 patients with pT1 or pT2 rectal adenocarcinoma received radical resection at a single institution. Clinicopathologic factors were evaluated by univariate and multivariate analyses to identify risk factors for LNM. Results: A total of 943 patients (544 men and 399 women) treated for T1-2 rectal cancer were included in this study. LNM was found in 188 patients (19.9%). In multivariate analysis, lymphovascular invasion (LVI; P < 0.001, hazard ratio 11.472), poor differentiation (PD; P = 0.007, hazard ratio 3.218), and depth of invasion (presence of pT2; P = 0.032, hazard ratio 1.694) were significantly related to nodal involvement. The incidence for LNM lesions in the presence of LVI, PD, and pT2 was 68.8, 50.0, and 23.1%, respectively, while that for pT1 carcinomas with no LVI or PD was 7.5%. Conclusions: LVI, PD, and pT2 are independent risk factors predicting LNM in pT1-2 rectal carcinoma. [ABSTRACT FROM AUTHOR]

Various types of polyunsaturated fatty acids (PUFAs) have been suggested to exert different effects on the colon in terms of promotion or inhibition of tumor development. Results of in vitro and in vivo studies are, however, inconsistent and it remains unclear whether or not the cellular effects of PUFAs change along with the malignant transformation of colonic cells. In this study, we used the NIH3T3 cell line and its SIC (sigmoid colon cancer) oncogene transformants to compare the effects of PUFAs on the proliferation of non-malignant and malignant cells. We also determined the cellular utilization of fatty acids in media by a high-performance liquid chromatography method. The addition of exogenous arachidonic acid (ARA, an n-6 fatty acid), eicosapentaenoic acid (EPA, n-3), and docosahexaenoic acid (DHA, n-3) exerted different effects on NIH3T3 cells, and on SIC transformants, in which selective inhibitory effects were observed at media concentrations ranging from 10 to 20 microg/ml. In cells cultured in media supplemented with EPA or DHA at a concentration of 2 microg/ml, which had no effect on cell proliferation, the cellular utilization of linoleic acid (n-6), a precursor of n-3 fatty acids, was inhibited. This inhibition was stronger in SIC transformants than in NIH3T3 cells (P < 0.05). There was no difference in the utilization of fatty acids between the two cell lines cultured in media supplemented with ARA. We conclude that the cellular response to exogenous long-chain PUFAs is modified during the course of malignant transformation, and that EPA and DHA (n-3 PUFAs) appear to have specific inhibitory effects on cancer cells and may thus enhance the host defense against colon cancer. [ABSTRACT FROM AUTHOR]