Review of single incision laparoscopic surgery in colorectal surgery

As surgical techniques continue to move towards less invasive techniques,single incision laparoscopic surgery(SILS),a hybrid between traditional multiport laparoscopy and natural orifice transluminal endoscopic surgery,was introduced to further the enhanced outcomes of multiport laparoscopy. The safety and feasibility of SILS for both benign and malignant colorectal disease has been proven. SILS provides the potential for improved cosmesis,postoperative pain,recovery time,and quality of life at the drawback of higher technical skill required. In this article,we review the history,describe the available technology and techniques,and evaluate the benefits and limitations of SILS for colorectal surgery in the published literature.

Incidence trends and predictors for cost and average lengths of stay in colorectal cancer surgery

AIM:To evaluate the changing trends and outcomes of colorectal cancer(CRC)surgery performed at a large single institution in Taiwan.METHODS:This study retrospectively analyzed 778patients who received colorectal cancer surgery at E-Da Hospital in Taiwan from 2004 to 2009.These patients were from health examination,inpatient or emergency settings.The following attributes were analyzed in patients who had undergone CRC surgical procedures:gender,age,source,surgical type,tumor number,tumor size,number of lymph node metastasis,pathologic differentiation,chemotherapy,distant metastases,tumor site,tumor stage,average hospitalization cost and average lengths of stay(ALOS).The odds ratio and95%confidence intervals were calculated to assess the relative rate of change.Regression models were employed to predict average hospitalization cost and ALOS.RESULTS:The study sample included 458(58.87%)males and 320(41.13%)females with a mean age of64.53 years(standard deviation,12.33 years;range,28-86 years).The principal patient source came from inpatient and emergency room(96.02%).The principal tumor sites were noted at the sigmoid colon(35.73%)and rectum(30.46%).Most patients exhibited a tumor stage of 2(37.28%)or 3(34.19%).The number of new CRC surgeries performed per 100000 persons was12.21 in 2004 and gradually increased to 17.89 in 2009,representing a change of 46.52%.During the same period,the average hospitalization cost and ALOS decreased from$5303 to$4062 and from 19.7 to 14.4 d,respectively.The following factors were associated with considerably decreased hospital resource utilization:age,source,surgical type,tumor size,tumor site,and tumor stage.CONCLUSION:These results can be generalized to patient populations elsewhere in Taiwan and to other countries with similar patient profiles.

Short-term outcomes after laparoscopic colorectal surgery in patients with previous abdominal surgery: A systematic review

AIM: To perform a systematic review focusing on shortterm outcomes after colorectal surgery in patients with previous abdominal open surgery(PAOS).METHODS: A broad literature search was performed with the terms "colorectal", "colectomy", "PAOS", "previous surgery" and "PAOS". Studies were included if their topic was laparoscopic colorectal surgery in patients with PAOS, whether descriptive or comparative. Endpoints of interest were conversion rates, inadvertent enterotomy and morbidity. Analysis of articles was made according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses.RESULTS: From a total of 394 citations, 13 full-texts achieved selection criteria to be included in the study. Twelve of them compared patients with and without PAOS. All studies were retrospective and comparative and two were case-matched. The selected studies comprised a total of 5005 patients, 1865 with PAOS. Among the later, only 294(16%) had history of a midline incision for previous gastrointestinal surgery. Conversion rates were significantly higher in 3 of 12 studies and inadvertent enterotomy during laparoscopywas more prevalent in 3 of 5 studies that disclosed this event. Morbidity was similar in the majority of studies. A quantitative analysis(meta-analysis) could not be performed due to heterogeneity of the studies. CONCLUSION: Conversion rates were slightly higher in PAOS groups, although not statistical significant in most studies. History of PAOS did not implicate in higher morbidity rates.

Adenocarcinoma of sigmoid colon with metastasis to an ovarian mature teratoma: A case report

BACKGROUND Colorectal cancer ranks third in global cancer-related mortality,often due to metastases to liver and lungs.Ovarian metastases are less common,accounting for 3.6%to 7.4%of cases.In contrast,mature ovarian teratomas are frequently benign.Tumor-to-tumor metastasis is a rare phenomenon,with a limited number of documented cases.Three cases of mature ovarian teratomas metastasizing from different cancers have been reported.This report focuses on a case of tumor-totumor metastasis from sigmoid colon adenocarcinoma to a mature ovarian teratoma.CASE SUMMARY A 41-year-old Taiwan residents woman with no known systemic diseases presented with lower back pain,which led to imaging revealing malignant lesions in the spine,pelvis,liver,and multiple lung metastases.She was diagnosed with sigmoid colon adenocarcinoma with metastases to the liver,lung,bone,and a left ovarian teratoma.Treatment involved radiotherapy and chemotherapy,resulting in regression of the primary tumor and stable lung and liver lesions.Due to abdominal symptoms,she underwent exploratory surgery,unveiling a mature teratoma in the left ovary with signs of metastatic adenocarcinoma.CONCLUSION Consider resecting mature ovarian teratomas with concurrent colorectal adenocarcinoma to prevent tumor-to-tumor metastasis.

Surgery for inflammatory bowel disease

Despite the new and ever expanding array of medications for the treatment of inflammatory bowel disease (IBD), there are still clear indications for operative management of IBD and its complications. We present an overview of indications, procedures, considerations, and controversies in the surgical therapy of IBD.

Robotic surgery for rectal cancer: A systematic review of current practice

AIM: To give a comprehensive review of current litera-ture on robotic rectal cancer surgery.METHODS: A systematic review of current literature via PubMed and Embase search engines was per-formed to identify relevant articles from january 2007 to november 2013. The keywords used were: "robotic surgery", "surgical robotics", "laparoscopic computer-assisted surgery", "colectomy" and "rectal resection". RESULTS: After the initial screen of 380 articles, 20 pa-pers were selected for review. A total of 1062 patients(male 64.0%) with a mean age of 61.1 years and body mass index of 24.9 kg/m2 were included in the review.Out of 1062 robotic-assisted operations, 831(78.2%) anterior and low anterior resections, 132(12.4%) in-tersphincteric resection with coloanal anastomosis, 98(9.3%) abdominoperineal resections and 1(0.1%) Hart-mann's operation were included in the review. Robotic rectal surgery was associated with longer operative time but with comparable oncological results and anastomotic leak rate when compared with laparoscopic rectal surgery. CONCLUSION: Robotic colorectal surgery has con-tinued to evolve to its current state with promising re-sults; feasible surgical option with low conversion rate and comparable short-term oncological results. The challenges faced with robotic surgery are for more high quality studies to justify its cost.

Efficacy and safety of transnasal butorphanol for pain relief after anal surgery

AIM:To compare the analgesic properties and efficacy of transnasal butorphanol with intramuscular meperidine after anal surgery.METHODS: Sixty patients who underwent fistulectomy were enrolled in the study from January 2006 to December 2007. They were randomly divided into transnasal butorphanol (n=30) or intramuscular meperidine (n=30) treatment groups. Assessment of postoperative pain was made using a visual analogue scale (VAS). The VAS score was recorded 6 h after the completion of surgery, before receiving the first dose of analgesic, 60 min after analgesia and the next morning. Any adverse clinical effects such as somnolence, dizziness, nausea or vomiting were recorded. Satisfaction with narcotic efficacy, desire to use the particular analgesic in the future and any complaints were recorded by patients using questionnaires before being discharged.RESULTS: Forty-two men and eighteen women were included in the study. There were no significant differences in VAS scores between the groups within 24 h. Length of hospital stay and the incidence of adverse effects between the groups were similar. In addition, most patients were satisfied with butorphanol nasal spray and wished to receive this analgesic in the future, if needed.CONCLUSION: Butorphanol nasal spray is effective for the relief of pain after fistulectomy. However, it offered patients more convenient usage and would be suitable for outpatients.

Oxaliplatin-induced severe anaphylactic reactions in metastatic colorectal cancer: Case series analysis

AIM: To investigate oxaliplatin-induced severe anaphylactic reactions (SAR) in metastatic colorectal cancer in a retrospective case series analysis and to conduct a systemic literature review. METHODS: During a 6-year period from 2006 to 2011 at Kaohsiung Veterans General Hospital, a total of 412 patients exposed to oxaliplatin-related chemotherapy were retrospectively reviewed. Relevant Englishlanguage studies regarding life-threatening SAR following oxaliplatin were also reviewed in MEDLINE and PubMed search. RESULTS: Eight patients (1.9%, 8 of 412 cases) were identified. Seven patients were successful resuscitated without any sequelae and one patient expired. We changed the chemotherapy regimen in five patients and rechallenged oxaliplatin use in patient 3. Twenty-three relevant English-language studies with 66 patients were reported. Patients received a median of 10 cycles of oxaliplatin (range, 2 to 29). Most common symptoms were respiratory distress (60%), fever (55%), and hypotension (54%). Three fatal events were reported (4.5%). Eleven patients (16%) of the 66 cases were rechallenged by oxaliplatin. CONCLUSION: SAR must be considered in patients receiving oxaliplatin-related chemotherapy, especially in heavily pretreated patients. Further studies on the mechanism, predictors, preventive methods and management of oxaliplatin-related SAR are recommended.

Role of minimally invasive surgery for rectal cancer

Rectal cancer is one of the most common malignancies worldwide.Surgical resection for rectal cancer usually requires a proctectomy with respective lymphadenectomy(total mesorectal excision).This has traditionally been performed transabdominally through an open incision.Over the last thirty years,minimally invasive surgery platforms have rapidly evolved with the goal to accomplish the same quality rectal resection through a less invasive approach.There are currently three resective modalities that complement the traditional open operation:(1)Laparoscopic surgery;(2)Robotic surgery;and(3)Transanal total mesorectal excision.In addition,there are several platforms to carry out transluminal local excisions(without lymphadenectomy).Evidence on the various modalities is of mixed to moderate quality.It is unreasonable to expect a randomized comparison of all options in a single trial.This review aims at reviewing in detail the various techniques in regard to intra-/perioperative benchmarks,recovery and complications,oncological and functional outcomes.

Colorectal cancer in young adults: A difficult challenge

Sporadic colorectal cancer(CRC) is traditionally diagnosed after the sixth decade of life,and current recommendations for surveillance include only patients older than 50 years of age. However,an increasing incidence of CRC in patients less than 40 years of age has been reported. This occurrence has been attributed to different molecular features and low suspicion of CRC in young symptomatic individuals. When confronting young-onset CRC with older patients,issues such as biological aggressiveness,stage at diagnosis and clinical outcomes seem to differ in many aspects. In the future,the identification of the molecular profile underlying the early development of sporadic CRC will help to plan tailored screening recommendations and improve management. Besides that,differential diagnosis with CRC linked with hereditary syndromes is necessary to provide adequate patient treatment and family screening. Until we find the answers to some of these doubts,doctors should raise suspicion when evaluating an young adult and be aware of this risk and consequences of a late diagnosis.

Present and future of metastatic colorectal cancer treatment: A review of new candidate targets

In the last two decades, great efforts have been made in the treatment of metastatic colorectal cancer(m CRC) due to the approval of new target agents for cytotoxic drugs. Unfortunately, a large percentage of patients present with metastasis at the time of diagnosis or relapse after a few months. The complex molecular heterogeneity of this disease is not completely understood; to date, there is a lack of predictive biomarkers that can be used to select subsets of patients who may respond to target drugs. Only the RAS-mutation status is used to predict resistance to anti-epidermal growth factor receptor agents in patients with m CRC. In this review, we describe approved targeted therapies for the management of metastatic m CRC and discuss new candidate targets on the horizon.

Chemotherapy plus percutaneous radiofrequency ablation in patients with inoperable colorectal liver metastases

AIM:To access the efficacy of chemotherapy plus radiofrequency ablation(RFA)as one line of treatment in inoperable colorectal liver metastases.METHODS:Eligible patients were included in three PhaseⅡstudies.In the first study percutaneous RFA was used first followed by 6 cycles of 5-fluorouracil,leucovorin and irinotecan combination(FOLFIRI)(adjunctive chemotherapy trial).In the other two,chemotherapy(FOLFIRI or 5-fluorouracil,leucovorin and oxaliplatin combination)up to 12 cycles was used first with percutaneous RFA offered to responding patients (primary chemotherapy trials).RESULTS:Thirteen patients were included in the adjunctive chemotherapy trial and 17 in the other two.At inclusion they had 1-4 liver metastases(up to 6.5 cm in size).Two patients died during chemotherapy.All patients in the adjunctive chemotherapy trial and 44%in the primary chemotherapy studies had their metastases ablated.Median PFS and overall survival in the adjunctive study were 13 and 24 mo respectively while in the primary chemotherapy studies they were 10 and 21 mo respectively.Eighty one percent of the patients had tumour relapse in at least one previously ablated lesion.CONCLUSION:Chemotherapy plus RFA in patients with low volume inoperable colorectal liver metastases seems safe and relatively effective.The high local recurrence rate is of concern.

Outcomes of neoadjuvant chemoradiotherapy followed by radical resection for T4 colorectal cancer

BACKGROUND Patients with clinical T4 colorectal cancer(CRC)have a poor prognosis because of compromised surgical margins.Neoadjuvant therapy may be effective in downstaging tumors,thereby rendering possible radical resection with clear margins.AIM To evaluate tumor downsizing and resection with clear margins in T4 CRC patients undergoing neoadjuvant concurrent chemoradiotherapy followed by surgery.METHODS This study retrospectively included 86 eligible patients with clinical T4 CRC who underwent neoadjuvant concurrent chemoradiotherapy followed by radical resection.Neoadjuvant therapy consisted of radiation therapy at a dose of 45-50.4 Gy and chemotherapy agents,either FOLFOX or capecitabine.A circumferential resection margin(CRM)of<1 mm was considered to be a positive margin.We defined pathological complete response(p CR)as the absence of any malignant cells in a specimen,including the primary tumor and lymph nodes.A multivariate logistic regression model was used to identify independent predictive factors for p CR.RESULTS For 86 patients who underwent neoadjuvant chemoradiotherapy and surgery,the rate of p CR was 14%,and the R0 resection rate was 91.9%.Of the 61 patients with rectal cancer,7(11.5%)achieved p CR and 5(8.2%)had positive CRMs.Of the 25 patients with colon cancer,5(20%)achieved p CR and 2(8%)had positive CRMs.We observed that the FOLFOX regimen was an independent predictor of p CR(P=0.046).After a median follow-up of 47 mo,the estimated 5-year overall survival(OS)and disease-free survival(DFS)rates were 70.8%and 61.4%,respectively.Multivariate analysis revealed that a tumor with a negative resection margin was associated with improved DFS(P=0.014)and OS(P=0.001).Patients who achieved p CR exhibited longer DFS(P=0.042)and OS(P=0.003)than those who did not.CONCLUSION Neoadjuvant concurrent chemoradiotherapy engenders favorable p CR and R0 resection rates among patients with T4 CRC.The R0 resection rate and p CR are independent prognostic factors for patients with T4 CRC.

Laparoscopic surgery for complex and recurrent Crohn's disease

Crohn's disease(CD) is a chronic inflammatory disease of digestive tract. Approximately 70% of patients with CD require surgical intervention within 10 years of their initial diagnosis, despite advanced medical treatment alternatives including biologics, immune suppressive drugs and steroids. Refractory to medical treatment in CD patients is the common indication for surgery. Unfortunately, surgery cannot cure the disease. Minimally invasive treatment modalities can be suitable for CD patients due to the benign nature of the disease especially at the time of index surgery. However,laparoscopic management in fistulizing or recurrent disease is controversial. Intractable fibrotic strictures with obstruction, fistulas with abscess formation and hemorrhage are the surgical indications of recurrent CD,which are also complicating laparoscopic treatments.Nevertheless, laparoscopy can be performed in selected CD patients with safety, and may provide better outcomes compared to open surgery. The common complication after laparoscopic intervention is postoperative ileus seems and this may strongly relate excessive manipulation of the bowel during dissection. But additionally, unsuccessful laparoscopic attempts requiring conversion to open surgery have been a major concern due to presumed risk of worse outcomes. However, recent data show that conversions do not to worsen the outcomes of colorectal surgery in experienced hands. In conclusion, laparoscopic treatment modalities in recurrent CD patients have promising outcomes when it is used selectively.

Differential DNA methylation analysis of SUMF2,ADAMTS5,and PXDN provides novel insights into colorectal cancer prognosis prediction in Taiwan

BACKGROUND Patients with colorectal cancer(CRC)undergo surgery,as well as perioperative chemoradiation or adjuvant chemotherapy primarily based on the tumor–node–metastasis(TNM)cancer staging system.However,treatment responses and prognostic outcomes of patients within the same stage vary markedly.The potential use of novel biomarkers can improve prognostication and shared decision making before implementation into certain therapies.AIM To investigate whether SUMF2,ADAMTS5,and PXDN methylation status could be associated with CRC prognosis.METHODS We conducted a Taiwan region cohort study involving 208 patients with CRC recruited from TriService General Hospital and applied the candidate gene approach to identify three genes involved in oncogenesis pathways.A methylation-specific polymerase chain reaction(MS-PCR)and Epi TYPER DNA methylation analysis were employed to detect methylation status and to quantify the methylation level of candidate genes in tumor tissue and adjacent normal tissue from participants.We evaluated SUMF2,ADAMTS5,and PXDN methylation as predictors of prognosis,including recurrence-free survival(RFS),progression-free survival(PFS),and overall survival(OS),using a Cox regression model and Kaplan–Meier analysis.RESULTS We revealed various outcomes related to methylation and prognosis.Significantly shorter PFS and OS were associated with the CpG_3+CpG_7 hypermethylation of SUMF2 from tumor tissue compared with CpG_3+CpG_7 hypomethylation[hazard ratio(HR)=2.24,95%confidence interval(CI)=1.03-4.85 for PFS,HR=2.56 and 95%CI=1.08-6.04 for OS].By contrast,a significantly longer RFS was associated with CpG_2 and CpG_13 hypermethylation of ADAMTS5 from normal tissue compared with CpG_2 and CpG_13 hypomethylation[HR(95%CI)=0.15(0.03-0.71)for CpG_2 and 0.20(0.04-0.97)for CpG_13].The relationship between the methylation status of PXDN and the prognosis of CRC did not reach statistical significance.CONCLUSION Our study found that CpG_3+CpG_7 hypermethylation of SUMF2 from tumor tissue was associated with significantly shorter PFS and OS compared with CpG_3+CpG_7 hypomethylation.CpG_2 and CpG_13 hypermethylation of ADAMTS5 from normal tissue was associated with a significantly longer RFS compared with CpG_2 and CpG_13 hypomethylation.These methylationrelated biomarkers which have implications for CRC prognosis prediction may aid physicians in clinical decision-making.

MTNR1B polymorphisms with CDKN2A and MGMT methylation status are associated with poor prognosis of colorectal cancer in Taiwan

BACKGROUND Identifying novel colorectal cancer(CRC)prognostic biomarkers is crucial to helping clinicians make appropriate therapy decisions.Melatonin plays a major role in managing the circadian rhythm and exerts oncostatic effects on different kinds of tumours.AIM To explore the relationship between MTNR1B single-nucleotide polymorphism(SNPs)combined with gene hypermethylation and CRC prognosis.METHODS A total of 94 CRC tumour tissues were investigated.Genotyping for the four MTNR1B SNPs(rs1387153,rs2166706,rs10830963,and rs1447352)was performed using multiplex polymerase chain reaction.The relationships between the MTNR1B SNPs and CRC 5-year overall survival(OS)was assessed by calculating hazard ratios with 95%CIs.RESULTS All SNPs(rs1387153,rs2166706,rs10830963,and rs1447352)were correlated with decreased 5-year OS.In stratified analysis,rs1387153,rs10830963,and rs1447352 risk genotype combined with CDKN2A and MGMT methylation status were associated with 5-year OS.A strong cumulative effect of the four polymorphisms on CRC prognosis was observed.Four haplotypes of MTNR1B SNPs were also associated with the 5-year OS.MTNR1B SNPs combined with CDKN2A and MGMT gene methylation status could be used to predict shorter CRC survival.CONCLUSION The novel genetic biomarkers combined with epigenetic biomarkers may be predictive tool for CRC prognosis and thus could be used to individualise treatment for patients with CRC.

Study of Vitamin D Receptor (VDR) Gene Polymorphisms among Egyptian Cohort Patients with Different Stages of Colorectal Cancer

Colorectal cancer represents the third cancer worldwide. Studies showed thatinsufficient levels of vitamin D may result in colorectal cancer. Genetic variations in genes controlling vitamin D activity would play a role in determining susceptibility to colorectal cancer. Aim of the work: to study the different genotypes of VDR polymorphisms and detect the association between serum levels of 25(OH)VitD and 1,25(OH)2VitD among sample of Egyptian patients with different stages of colorectal cancer. Methods: Ninety patients (60 with different stages of colorectal cancer and 30 patients with benign pathology of the colon) together with 30 healthy controls were examined using PCR-RFLP analysis for FokI, ApaI and TaqI polymorphisms. Results: Genotype distribution for ApaI polymorphism showed no statistically significant difference between patients (colorectal cancer and benign) and controls with p = 0.1. There was no statistically significant difference in FokI polymorphism where p = 0.26 and genotype distribution for TaqI was also insignificant with p = 0.016. The median serum level of 25(OH)VitD was low in cancer cases compared to the control group and benign cases with (p 0.001). There was no statisticallysignificant difference of median serum level of 1,25(OH)2VitD between benign and cancer cases. There was statistically significant difference of median serum level of 25(OH)VitD and 1,25(OH)2VitD between stage I and stage II with (p = 0.004) and (p 0.001), and between stage I and stage III with (p = 0.001)and (p 0.001), but no statistically significant difference between stage II and III with (p = 0.514). Conclusions: There is ethnic variability in vitamin D receptor gene polymorphisms. The lack of significant association of the studied gene polymorphism in our population suggests that its association with other functionally known gene polymorphism might have a role in the pathogenesis of colorectal cancer.

Mutation analysis of 13 driver genes of colorectalcancer-related pathways in Taiwan Residents patients

AIM To investigate the driver gene mutations associatedwith colorectal cancer （CRC） in the Taiwan Residentspopulation.METHODS： In this study, 103 patients with CRCwere evaluated. The samples consisted of 66 menand 37 women with a median age of 59 years and anage range of 26-86 years. We used high-resolutionmelting analysis （HRM） and direct DNA sequencing tocharacterize the mutations in 13 driver genes of CRCrelatedpathways. The HRM assays were conductedusing the LightCycler？ 480 Instrument provided with the software LightCycler 480 Gene Scanning SoftwareVersion 1.5. We also compared the clinicopathologicaldata of CRC patients with the driver gene mutationstatus.RESULTS： Of the 103 patients evaluated, 73.79%had mutations in one of the 13 driver genes. Wediscovered 18 novel mutations in APC , MLH1 , MSH2 ,PMS2 , SMAD4 and TP53 that have not been previouslyreported. Additionally, we found 16 de novo mutationsin APC , BMPR1A , MLH1 , MSH2 , MSH6 , MUTYH andPMS2 in cancerous tissues previously reported in thedbSNP database; however, these mutations couldnot be detected in peripheral blood cells. The APCmutation correlates with lymph node metastasis（34.69% vs 12.96%, P = 0.009） and cancer stage（34.78% vs 14.04%, P = 0.013）. No association wasobserved between other driver gene mutations andclinicopathological features. Furthermore, having twoor more driver gene mutations correlates with thedegree of lymph node metastasis （42.86% vs 24.07%,P = 0.043）.CONCLUSION： Our findings confirm the importanceof 13 CRC-related pathway driver genes in the developmentof CRC in Taiwan Residents patients.

Nomogram to predict permanent stoma in rectal cancer patients after sphincter-saving surgery

BACKGROUND Approximately 20 percent of patients with a tumour localized in the low rectum still encounter the possibility of requiring permanent stoma(PS), which can cause drastic changes in lifestyle and physical perceptions.AIM To determine the risk factors for PS and to develop a prediction model to predict the probability of PS in rectal cancer patients after sphincter-saving surgery.METHODS A retrospective cohort of 421 rectal cancer patients who underwent radical surgery at Taipei Medical University Hospital between January 2012 and December 2020 was included in this study. Univariate and multivariate analyses were performed to identify the independent risk factors for PS. A nomogram was developed according to the independent risk factors obtained in the multivariate analysis. The performance of the nomogram was assessed using a receiver operating characteristic curve and a calibration curve.RESULTS The PS rate after sphincter-saving surgery was 15.1%(59/391) in our study after a median follow-up of 47.3 mo(range 7–114 mo). Multivariate logistic regression analysis demonstrated that local recurrence, perirectal abscess, anastomosis site stenosis, perineural invasion, tumor size and operative time were independent risk factors for PS. These identified risk factors were incorporated into the nomogram, and the concordance index of this model was 0.903(95%CI: 0.851-0.955). According to the calibration curves, the nomogram represents a perfect prediction model.CONCLUSION Several risk factors for PS after sphincter-saving surgery were identified. Our nomogram exhibited perfect predictive ability and will improve a physician’s ability to communicate the benefits and risks of various treatment options in shared decision making.

Novel methylation gene panel in adjacent normal tissues predicts poor prognosis of colorectal cancer in Taiwan

BACKGROUND It is evident that current clinical criteria are suboptimal to accurately estimate patient prognosis.Studies have identified epigenetic aberrant changes as novel prognostic factors for colorectal cancer(CRC).AIM To estimate whether a methylation gene panel in different clinical stages can reflect a different prognosis.METHODS We enrolled 120 CRC patients from Tri-Service General Hospital in Taiwan and used the candidate gene approach to select six genes involved in carcinogenesis pathways.Patients were divided into two groups based on the methylation status of the six evaluated genes,namely,the<3 aberrancy group and≥3 aberrancy group.Various tumor stages were divided into two subgroups(local and advanced stages)on the basis of the pathological type of the following tissues:Tumor and adjacent normal tissues(matched normal).We assessed DNA methylation in tumors and adjacent normal tissues from CRC patients and analyzed the association between DNA methylation with different cancer stages and the prognostic outcome including time to progression(TTP)and overall survival.RESULTS We observed a significantly increasing trend of hazard ratio as the number of hypermethylated genes increased both in normal tissue and tumor tissue.The 5-year TTP survival curves showed a significant difference between the≥3 aberrancy group and the<3 aberrancy group.Compared with the<3 aberrancy group,a significantly shorter TTP was observed in the≥3 aberrancy group.We further analyzed the interaction between CRC prognosis and different cancer stages(local and advanced)according to the methylation status of the selected genes in both types of tissues.There was a significantly shorter 5-year TTP for tumors at advanced stages with the promoter methylation status of selected genes than for those with local stages.We found an interaction between cancer stages and the promoter methylation status of selected genes in both types of tissues.CONCLUSION Our data provide a significant association between the methylation markers in normal tissues with advanced stage and prognosis of CRC.We recommend using these novel markers to assist in clinical decision-making.