How robotics is changing and will change the field of colorectal surgery

During the last decade there has been a significant upward trend in colon and rectal minimally invasive surgery which can be attributed largely to the acceptance of robotic surgery platforms such as the da Vinci?robotic system.The fourth generation da Vinci?system,introduced in 2014,includes integrated table motion,intelligent laser targeted docking and more sophisticated instrumentation and imaging.These developments have enabled more surgeons to efficiently and safely perform multi-quadrant operations.Firefly?technology allows assessment of colon perfusion and identification of ureters,and has shown potential in detecting occult recurrence or metastasis using molecular-labelled tumor markers.Wristed instrumentation has increased the technical ease of intracorporeal anastomosis(ICA)for many surgeons,leading to more common use of ICA during right colectomy.Advanced imaging has shown potential to decrease the incidence of presacral nerve injury and improve urogenital outcomes after pelvic surgery,as has been the case in robotic urologic procedures.Finally,the robotic platform lends itself to surgical simulation for surgical trainees,as a pre-operative tool for mock operations and as an ongoing assessment tool for established colorectal surgeons.Given these advantages,surgeons should anticipate continued and increased utilization of this beneficial technology.

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.

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.

Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale

Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults.

Postoperative ileus: Impact of pharmacological treatment,laparoscopic surgery and enhanced recovery pathways

Almost all patients develop postoperative ileus (POI) after abdominal surgery.POI represents the single largest factor influencing length of stay (LOS) after bowel resection,and has great implications for patients and resource utilization in health care.New methods to treat and decrease the length of POI are therefore of great importance.During the past decade,a substantial amount of research has been performed evaluating POI,and great progress has been made in our understanding and treatment of POI.Laparoscopic procedures,enhanced recovery pathways and pharmacologic treatment have been introduced.Each factor has substantially contributed to decreasing the length of POI and thus LOS after bowel resection.This editorial outlines resource utilization of POI,normal physiology of gut motility and pathogenesis of POI.Pharmacological treatment,fast track protocols and laparoscopic surgery can each have significant impact on pathways causing POI.The optimal integration of these treatment options continues to be assessed in prospective studies.

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.

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.

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.

Gene expression profile of peripheral blood in colorectal cancer

AIM: Optimal molecular markers for detecting colorectal cancer (CRC) in a blood-based assay were evaluated.

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.

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.

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.

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.

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.

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.

Verification of gene expression profiles for colorectal cancer using 12 internet public microarray datasets

AIM: To verify gene expression profiles for colorectal cancer using 12 internet public microarray datasets.

Quality of life and symptom distress after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy(CRS/HIPEC)for peritoneal surface malignancy can effectively control the disease,however it is also associated with adverse effects which may affect quality of life(QoL).AIM To investigate early perioperative QoL after CRS/HIPEC,which has not been discussed in Taiwan.METHODS This single institution,observational cohort study enrolled patients who received CRS/HIPEC.We assessed QoL using the Taiwan residents version of the MD Anderson Symptom Inventory(MDASI-T)and European Organization Research and Treatment of Cancer Core Quality of Life Questionnaire(EORTC QLQ-C30).Participants completed the questionnaires before CRS/HIPEC(S1),at the first outpatient follow-up(S2),and 3 mo after CRS/HIPEC(S3).RESULTS Fifty-eight patients were analyzed.There was no significant perioperative difference in global health status.Significant changes in physical and role functioning scores decreased at S2,and fatigue and pain scores increased at S2 but returned to baseline at S3.Multiple regression analysis showed that age and performance status were significantly correlated with QoL.In the MDASI-T questionnaire,distress/feeling upset and lack of appetite had the highest scores at S1,compared to fatigue and distress/feeling upset at S2,and fatigue and lack of appetite at S3.The leading interference items were working at S1 and S2 and activity at S3.MDASI-T scores were significantly negatively correlated with the EORTC QLQ-C30 results.CONCLUSION QoL and symptom severity improved or returned to baseline in most categories within 3 mo after CRS/HIPEC.Our findings can help with preoperative consultation and perioperative care.

Effects of the number of neoadjuvant therapy cycles on clinical outcomes, safety, and survival in patients with metastatic colorectal cancer undergoing metastasectomy

The controversial outcomes in patients with metastatic colorectal cancer(mCRC)highlight the need for developing effective systemic neoadjuvant treatment strategies to improve clinical results.The optimal treatment cycles in patients with mCRC for metastasectomy remain undefined.This retrospective study compared the efficacy,safety,and survival of cycles of neoadjuvant chemotherapy/targeted therapy for such patients.Sixty-four patients with mCRC who received neoadjuvant chemotherapy/targeted therapy following metastasectomy were enrolled between January 2018 and April 2022.Twenty-eight patients received 6 cycles of chemotherapy/targeted therapy,whereas 36 patients received≥7 cycles(median,13;range,7–20).Clinical outcomes,including response,progression-free survival(PFS),overall survival(OS),and adverse events,were compared between these two groups.Of the 64 patients,47(73.4%)were included in the response group,and 17(26.6%)were included in the nonresponse group.The analysis revealed chemotherapy/targeted therapy cycle and pretreatment serum carcinoembryonic antigen(CEA)level as independent predictors of the response as well as overall survival and chemotherapy/targeted therapy cycle as an independent predictor of progression(all p<0.05).Furthermore,our results revealed shorter operation time,lower estimated operative blood loss,higher response rate,lower progression rate,and higher survival rate in≥7 cycles of chemotherapy/targeted therapy group(all p<0.05),but no statistical differences in adverse events were observed between the two groups(all p>0.05).The median OS and PFS were 48 months(95%CI,40.855–55.145)and 28 months(95%CI,18.952–37.48)in the≥7-cycle group and 24 months(95%CI,22.038–25.962)and 13 months(95%CI,11.674–14.326)in the 6-cycle group,respectively(both p<0.001).The oncological outcomes in the≥7-cycle group were significantly better than those in the 6-cycle group,without significant increases in adverse events.However,prospective randomized trials are mandatory to confirm the potential advantages of cycle numbers of neoadjuvant chemotherapy/targeted therapy.

Is ypTNM staging a comparable predictor as pTNM staging for survival in non-metastatic rectal cancer after preoperative chemoradiation therapy?

Abstract:Background:The pTNM staging system is widely recognized as the most effective prognostic indicator for cancer.The latest update of this staging system introduced a new pathological staging system(ypTNM)for patients receiving neoadjuvant chemoradiotherapy(NACRT).However,whether the prognostic value of the ypTNM staging system for rectal cancer is similar to that of the pTNM staging system remains unclear.This study was conducted to compare the ypTNM and pTNM staging systems in terms of their prognostic value for patients with nonmetastatic rectal cancer undergoing proctectomy.Material and Methods:This study was conducted at a large teaching hospital.Between January 2014 and December 2022,542 patients with rectal cancer were analyzed(median follow-up period,60 months;range,6–105 months).Of them,258 and 284 were included in the pTNM and ypTNM groups,respectively.Inverse probability of treatment weighting(IPTW)was performed to account for the effects of confounders.Cox proportional-hazards regression was performed for the between-group comparison of overall survival(OS).Results:The crude model revealed that OS was similar between the two groups(p=0.607).After performing IPTW,we found that patients with the same ypTNM-and pTNM-classified stages had similar overall survival(hazard ratio=1.15;95%CI=0.76–1.73;p=0.5074).Conclusions:For patients with rectal cancer who have received preoperative NACRT,the prognostic value of ypTNM staging appears to be similar to that of pTNM staging,mostly because of the downstaging effect of neoadjuvant chemoradiotherapy。