Prediction of pathological complete response and prognosis in locally advanced rectal cancer

BACKGROUND Colorectal cancer is currently the third most common malignant tumor and the second leading cause of cancer-related death worldwide.Neoadjuvant chemoradiotherapy(nCRT)is standard for locally advanced rectal cancer(LARC).Except for pathological examination after resection,it is not known exactly whether LARC patients have achieved pathological complete response(pCR)before surgery.To date,there are no clear clinical indicators that can predict the efficacy of nCRT and patient outcomes.AIM To investigate the indicators that can predict pCR and long-term outcomes following nCRT in patients with LARC.METHODS Clinical data of 128 LARC patients admitted to our hospital between September 2013 and November 2022 were retrospectively analyzed.Patients were categorized into pCR and non-pCR groups.Univariate analysis(using the χ^(2) test or Fisher’s exact test)and logistic multivariate regression analysis were used to study clinical predictors affecting pCR.The 5-year disease-free survival(DFS)and overall survival(OS)rates were calculated using Kaplan-Meier analysis,and differences in survival curves were assessed with the log-rank test.RESULTS Univariate analysis showed that pretreatment carcinoembryonic antigen(CEA)level,lymphocyte-monocyte ratio(LMR),time interval between neoadjuvant therapy completion and total mesorectal excision,and tumor size were correlated with pCR.Multivariate results showed that CEA≤5 ng/mL(P=0.039),LMR>2.73(P=0.023),and time interval>10 wk(P=0.039)were independent predictors for pCR.Survival analysis demonstrated that patients in the pCR group had significantly higher 5-year DFS rates(94.7%vs 59.7%,P=0.002)and 5-year OS rates(95.8%vs 80.1%,P=0.019)compared to the non-pCR group.Tumor deposits(TDs)were significantly correlated with shorter DFS(P=0.002)and OS(P<0.001).CONCLUSION Pretreatment CEA,LMR,and time interval contribute to predicting nCRT efficacy in LARC patients.Achieving pCR demonstrates longer DFS and OS.TDs correlate with poor prognosis.

Compare clinical efficacy and safety of neoadjuvant therapy and neoadjuvant chemoradiotherapy for locally advanced rectal cancer: Meta-analysis

BACKGROUND To compare the efficacy and safety of total neoadjuvant therapy(TNT)and neoadjuvant chemoradiotherapy(nCRT)in the treatment of middle and low locally advanced rectal cancer.Our study will systematically collect and integrate studies to evaluate the ability of these two treatments to improve tumor shrinkage rates,surgical resection rates,tumor-free survival,and severe adverse events.AIM To provide clinicians and patients with more reliable treatment options to optimize treatment outcomes and quality of life for patients with locally advanced rectal cancer by comparing the advantages and disadvantages of the two treatment options.METHODS A full search of all clinical studies on the effectiveness and safety of TNT and nCRT for treating locally advanced rectal cancer identified in Chinese(CNKI,Wanfang,China Biomedical Literature Database)and English(PubMed,Embase)databases was performed.Two system assessors independently screened the studies according to the inclusion and exclusion criteria.Quality evaluation and RESULTS Finally,14 studies were included,six of which were randomized controlled studies.A total of 3797 patients were included,including 1865 in the TNT group and 1932 in the nCRT group.The two sets of baseline data were comparable.The results of the meta-analysis showed that the pCR rate[odds ratio(OR)=1.57,95%confidence interval(CI):1.30-1.90,P<0.00001],T stage degradation rate(OR=2.16,95%CI:1.63-2.57,P<0.00001),and R0 resection rate(OR=1.42,95%CI:1.09-1.85,P=0.009)were significantly greater in the nCRT group than in the nCRT group.There was no significant difference in the incidence of grade 3/4 acute toxicity or perioperative complications between the two groups.The 5-year OS[hazard ratio(HR)=0.84,95%CI:0.69-1.02,P=0.08]and DFS(HR=0.94,95%CI:0.03-1.39,P=0.74)of the TNT group were similar to those of the nCRT group.CONCLUSION TNT has greater clinical efficacy and safety than nCRT in the treatment of locally advanced rectal cancer.

Minimally invasive pelvic exenteration for primary or recurrent locally advanced rectal cancer:A glimpse into the future

Surgeons have grappled with the treatment of recurrent and T4b locally advanced rectal cancer(LARC)for many years.Their main objectives are to increase the overall survival and quality of life of the patients and to mitigate postoperative complications.Currently,pelvic exenteration(PE)with or without neoadjuvant treatment is a curative treatment when negative resection margins are achieved.The traditional open approach has been favored by many surgeons.However,the technological advancements in minimally invasive surgery have radically changed the surgical options.Recent studies have demonstrated promising results in postoperative complications and oncological outcomes after robotic or laparoscopic PE.A recent retrospective study entitled“Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer:A 9-year review”was published in the World Journal of Gastrointestinal Surgery.As we read this article with great interest,we decided to delve into the latest data regarding the benefits and risks of minimally invasive PE for LARC.Currently,the small number of suitable patients,limited surgeon experience,and steep learning curve are hindering the establishment of minimally invasive PE.

Hsa-miR-483-5p/mRNA network that regulates chemotherapy resistance in locally advanced rectal cancer identified through plasma exosome transcriptomics

BACKGROUND Chemoresistance is the primary contributor to distant metastasis in the context of neoadjuvant chemoradiotherapy(nCRT)for rectal cancer.However,the underlying mechanisms remain elusive.AIM To detect the differential expression profiles of plasma exosomal microRNAs(miRNAs)in poor and good responders and explore the potential mechanisms of chemoresistance.METHODS In this study,the profiles of plasma exosomal miRNAs were compared in two dimensions according to treatment responses(poor/good responders)and treatment courses(pre/post-nCRT)using RNA sequencing.RESULTS Exosome hsa-miR-483-5p was up-regulated in good responders post-nCRT.Bioinformatics analysis revealed that the target genes of hsa-miR-483-5p were mainly enriched in tumor-specific pathways,such as the MAPK signaling pathway,EGFR tyrosine kinase inhibitor resistance,Toll-like receptor signaling pathway,VEGF signaling pathway,and mTOR signaling pathway.Further analysis indicated that MAPK3,RAX2,and RNF165 were associated with inferior recurrence-free survival in patients with rectal cancer,and the profiles of MAPK3,TSPYL5,and ZNF-417 were correlated with tumor stage.In addition,the expression profiles of MAPK3,RNF165,and ZNF417 were negatively correlated with inhibitory concentration 50 values.Accordingly,an hsa-miR-483-5p/MAPK3/RNF 165/ZNF417 network was constructed.CONCLUSION This study provides insights into the mechanism of chemoresistance in terms of exosomal miRNAs.However,further research is required within the framework of our established miRNA-mRNA network.

Role of radiation therapy in neoadjuvant era in patients with locally advanced rectal cancer

Surgery remains the primary determinant of cure in patients with localized rectal cancer, and total mesorectal excision is now widely accepted as standard of care. The widespread implementation of neoadjuvant shortcourse radiotherapy (RT) or long-course chemoradiotherapy (CRT) has reduced local recurrence rates from 25% to 40% to less than 10%; Preoperative RT in resectable rectal cancer has a number of potential advantages, most importantly reducing local recurrence, and down-staging effect. In this article making a comprehensive literature review searching the reliable medical data bases of PubMed and Cochrane we present all available information on the role of radiation therapy alone or in combination with chemotherapy in preoperative setting of rectal cancer. Data reported show that in locally advanced rectal cancer the addition of radiation therapy or CRT pre surgically has significantly improved sphincter prevention surgery. Moreover, the addition of chemotherapy to radiation therapy in preoperative setting has significantly improved pathologic complete response rate and loco-regional control rate without improvement in sphincter preserving surgery. Finally, the results of recently published randomized trials have shown a significant improvement of prevs postoperative CRT on local control; however, there was no effect on overall survival.

Magnetic resonance imaging for diagnosis and neoadjuvant treatment evaluation in locally advanced rectal cancer:A pictorial review

High-resolution pelvic magnetic resonance imaging(MRI) is the primary method for staging rectal cancer.MRI is highly accurate in the primary staging of rectal cancer;however,it has not proven to be effective in restaging,especially in complete response evaluation after neoadjuvant therapy.Neoadjuvant chemoradiotherapy produces many changes in rectal tumors and on adjacent area,as a result,local tumor extent may not be accurately determined.However,adding diffusion-weighted sequences to the standard approach can improve diagnostic accuracy.In this pictorial review,an overview of the situation of MRI in the staging and re-staging of rectal cancer is exhibited as a pictorial assay.An experience-and literature-based discussion of limitations and difficulties in interpretation are also presented.

Neoadjuvant vs adjuvant pelvic radiotherapy for locally advanced rectal cancer: Which is superior?

The treatment of locally advanced rectal cancer including timing and dosage of radiotherapy, degree of sphincter preservation with neoadjuvant radiotherapy, and short and long term effects of radiotherapy are controversial topics. The MEDLINE, Cochrane Library databases, and meeting proceedings from the American Society of Clinical Oncology, were searched for reports of randomized controlled trials and meta-analyses comparing neoadjuvant and adjuvant radiotherapy with surgery to surgery alone for rectal cancer. Neoadjuvant radiotherapy shows superior results in terms of local control compared to adjuvant radiotherapy. Neither adjuvant or neoadjuvant radiotherapy impacts overall survival. Short course versus long course neoadjuvant radiotherapy remains controversial. There is insufficient data to conclude that neoadjuvant therapy improves rates of sphincter preserving surgery. Radiation significantly impacts anorectal and sexual function and includes both acute and long term toxicity. Data demonstrate that neoadjuvant radiation causes less toxicity compared to adjuvant radiotherapy, and specifically short course neoadjuvant radiation results in less toxicity than long course neoadjuvant radiation. Neoadjuvant radiotherapy is the preferred modality for administering radiation in locally advanced rectal cancer. There are significant side effects from radiation, including anorectal and sexual dysfunction, which may be less with short course neoadjuvant radiation.

Neoadjuvant chemoradiotherapy for locally advanced rectal cancer:The debate continues

Rectal carcinoma represents the 30% of all colorectal cancers, with about 40000 new cases/years. In the past two decades, the management of rectal cancer has made important progress, highlighting the main role of a multimodality strategy approach, combining surgery, radiation therapy and chemotherapy. Nowadays, surgery remains the primary treatment and neoadjuvant chemoradiotherapy, based on fluoropyrimidine(5-FU) continuous infusion, is considered the standard in locally advanced rectal carcinoma. The aim is to reduce the incidence of local recurrence and to perform a conservative surgery. To improve these purposes different drugs combination have been tested in the neo-adjuvant setting. At American Society of Clinical Oncology 2014 an important abstract was presented focusing on the role of adding oxaliplatin to concomitant treatment, in patients with locally advanced rectal carcinoma. Rodel et al reported on the CAO/ARO/AIO-04 randomized phase Ⅲ trial that compared standard treatment with 5-FU and radiation therapy, to oxaliplatin plus 5-FU inassociation with radiation therapy. The addition of oxaliplatin to the neo-adjuvant treatment has been shown to improve disease-free survival from 71.2% to 75.9%(P = 0.03). This editorial was planned to clarify the optimal treatment in patients with locally advanced rectal cancer, considering the results from CAO/ARO/AIO-04 study.

Locally advanced rectal cancer:The importance of a multidisciplinary approach

Rectal cancer accounts for a relevant part of colorectal cancer cases,with a mortality of 4-10/100000 per year.The development of locoregional recurrences and the occurrence of distant metastases both influences the prognosis of these patients.In the last two decades,new multimodality strategies have improved the prognosis of locally advanced rectal cancer with a significant reduction of local relapse and an increase in terms of overall survival.Radical surgery still remains the principal curative treatment and the introduction of total mesorectal excision has significantly achieved a reduction in terms of local recurrence rates.The employment of neoadjuvant treatment,delivered before surgery,also achieved an improved local control and an increasedsphincter preservation rate in low-lying tumors,with an acceptable acute and late toxicity.This review describes the multidisciplinary management of rectal cancer,focusing on the effectiveness of neoadjuvant chemoradiotherapy and of post-operative adjuvant chemotherapy both in the standard combined modality treatment programs and in the ongoing research to improve these regimens.

Combined value of apparent diffusion coefficient-standardized uptake value max in evaluation of post-treated locally advanced rectal cancer

AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive predictive value,in predicting the different group category response in related to TRG system,presented R^2 of 0.95.CONCLUSION:The functional imaging combining ADC and SUVmax in a single analysis permits to detect changes in cellular tissue structures useful for the assessment of tumour response after the neoadjuvant therapy in rectal cancer,increasing the sensitivity in correct depiction of treatment response than either method alone.

Laparoscopic lateral lymph node dissection in two fascial spaces for locally advanced lower rectal cancer

BACKGROUND The procedure for lateral lymph node(LLN)dissection(LLND)is complicated and can result in complications.We developed a technique for laparoscopic LLND based on two fascial spaces to simplify the procedure.AIM To clarify the anatomical basis of laparoscopic LLND in two fascial spaces and to evaluate its efficacy and safety in treating locally advanced low rectal cancer(LALRC).METHODS Cadaveric dissection was performed on 24 pelvises,and the fascial composition related to LLND was observed and described.Three dimensional-laparoscopic total mesorectal excision with LLND was performed in 20 patients with LALRC,and their clinical data were analyzed.RESULTS The cadaver study showed that the fascia propria of the rectum,urogenital fascia,vesicohypogastric fascia and parietal fascia lie side by side in a medial-lateral direction constituting the dissection plane for curative rectal cancer surgery,and the last three fasciae formed two spaces(Latzko's pararectal space and paravesical space)which were the surgical area for LLND.Laparoscopic LLND in two fascial spaces was performed successfully in all 20 patients.The median operating time,blood loss and postoperative hospitalization were 178(152-243)min,55(25-150)mL and 10(7-20)d,respectively.The median number of harvested LLNs was 8.6(6-12),and pathologically positive LLN metastasis was confirmed in 7(35.0%)cases.Postoperative complications included lower limb pain in 1 case and lymph leakage in 1 case.CONCLUSION Our preliminary surgical experience suggests that laparoscopic LLND based on fascial spaces is a feasible,effective and safe procedure for treating LALRC.

Bevacizumab in the pre-operative treatment of locally advanced rectal cancer: A systematic review

Despite advances in the management of patients with locally advanced, non-metastatic rectal adenocarcinoma (LARC), prognosis remains largely unsatisfactory due to a high rate of distant relapse. In fact, currently available neoadjuvant protocols, represented by fluoropyrimidine-based chemo-radiotherapy (CT-RT) or short-course RT, together with improved surgical techniques, have largely reduced the risk of local relapse, with limited impact on distant recurrence. Available results of phase III trials with additional cytotoxic agents combined with standard CT-RT are disappointing, as no significant reduction in the risk of recurrence has been demonstrated. In order to improve the control of micrometastatic disease, integrating targeted agents into neoadjuvant treatment protocols thus offers a rational approach. In particular, the antiangiogenic agent bevacizumab has demonstrated synergistic activity with both CT and RT in pre-clinical and clinical models, and thus may represent a suitable companion in the neoadjuvant treatment of LARC. Preliminary results of phase&#x02005;I-II clinical studies are promising and suggest potential clinical parameters and molecular predictive biomarkers useful for patient selection: treatment personalization is indeed the key in order to maximize the benefit while reducing the risk of more complex neoadjuvant treatment schedules.

High-dose-rate intraluminal brachytherapy during preoperative chemoradiation for locally advanced rectal cancers

AIM:To determine the feasibility and safety of high dose rate intraluminal brachytherapy(HDR-ILBT) boost during preoperative chemoradiation for rectal cancer.METHODS:Between 2008 and 2009,thirty-six patients with locally advanced rectal cancer(≥ T3 or N+),were treated initially with concurrent capecitabine(825 mg/m2 oral twice daily) and pelvic external beam radiotherapy(EBRT)(45 Gy in 25 fractions),then were randomized to group A;HDR-ILBT group(n = 17) to receive 5.5-7 Gy×2 to gross tumor volume(GTV) and group B;EBRT group(n = 19) to receive 5.4 Gy×3 fractions to GTV with EBRT.All patients underwent total mesorectal excision.RESULTS:Grade 3 acute toxicities were registered in 12 patients(70.6%) in group A and in 8(42.1%) in group B.Complete pathologic response of T stage(ypT0) in group A was registered in 10 patients(58.8%) and in group B,3 patients(15.8%) had ypT0(P < 0.0001).Sphincter preservation was reported in 6/9 patients(66.7%) in group A and in 5/10 patients(50%) in group B(P < 0.01).Overall radiological response was 68.15% and 66.04% in Group A and B,respectively.During a median follow up of 18 mo,late grade 1 and 2 sequelae were registered in 3 patients(17.6%) and 4 patients(21.1%) in the groups A and B,respectively.CONCLUSION:HDR-ILBT was found to be effective dose escalation technique in preoperative chemoradiation for rectal cancers,with higher response rates,downstaging and with manageable acute toxicities.

Whole lesion histogram analysis of apparent diffusion coefficient predicts therapy response in locally advanced rectal cancer

BACKGROUND Whole-tumor apparent diffusion coefficient(ADC)histogram analysis is relevant to predicting the neoadjuvant chemoradiation therapy(nCRT)response in patients with locally advanced rectal cancer(LARC).AIM To evaluate the performance of ADC histogram-derived parameters for predicting the outcomes of patients with LARC.METHODS This is a single-center,retrospective study,which included 48 patients with LARC.All patients underwent a pre-treatment magnetic resonance imaging(MRI)scan for primary tumor staging and a second restaging MRI for response evaluation.The sample was distributed as follows:18 responder patients(R)and 30 non-responders(non-R).Eight parameters derived from the whole-lesion histogram analysis(ADCmean,skewness,kurtosis,and ADC10^(th),25^(th),50^(th),75^(th),90^(th) percentiles),as well as the ADCmean from the hot spot region of interest(ROI),were calculated for each patient before and after treatment.Then all data were compared between R and non-R using the Mann-Whitney U test.Two measures of diagnostic accuracy were applied:the receiver operating characteristic curve and the diagnostic odds ratio(DOR).We also reported intra-and interobserver variability by calculating the intraclass correlation coefficient(ICC).RESULTS Post-nCRT kurtosis,as well as post-nCRT skewness,were significantly lower in R than in non-R(both P<0.001,respectively).We also found that,after treatment,R had a larger loss of both kurtosis and skewness than non-R(Δ%kurtosis and Δ skewness,P<0.001).Other parameters that demonstrated changes between groups were post-nCRT ADC10^(th),Δ%ADC10^(th),Δ%ADCmean,and ROIΔ%ADCmean.However,the best diagnostic performance was achieved byΔ%kurtosis at a threshold of 11.85%(Area under the receiver operating characteristic curve[AUC]=0.991,DOR=376),followed by post-nCRT kurtosis=0.78×10^(-3)mm^(2)/s(AUC=0.985,DOR=375.3),Δskewness=0.16(AUC=0.885,DOR=192.2)and post-nCRT skewness=1.59×10^(-3)mm^(2)/s(AUC=0.815,DOR=168.6).Finally,intraclass correlation coefficient analysis showed excellent intraobserver and interobserver agreement,ensuring the implementation of histogram analysis into routine clinical practice.CONCLUSION Whole-tumor ADC histogram parameters,particularly kurtosis and skewness,are relevant biomarkers for predicting the nCRT response in LARC.Both parameters appear to be more reliable than ADCmean from one-slice ROI.

Contemporary management of locally advanced rectal cancer:Resolving issues, controversies and shifting paradigms

Advancements in rectal cancer treatment have resulted in improvement only in locoregional control and have failed to address distant relapse, which is the predominant mode of treatment failure in rectal cancer. As the efficacy of conventional chemoradiotherapy（CRT） followed by total mesorectal excision（TME） reaches a plateau, the need for alternative strategies in locally advanced rectal cancer（LARC） has grown in relevance. Several novel strategies have been conceptualized to address this issue, including： 1） neoadjuvant induction and consolidation chemotherapy before CRT; 2） neoadjuvant chemotherapy alone to avoid the sequelae of radiation; and 3） nonoperative management for patients who achieved pathological or clinical complete response after CRT. This article explores the issues, recent advances and paradigm shifts in the management of LARC and emphasizes the need for a personalized treatment plan for each patient based on tumor stage, location, gene expression and quality of life.

Total neoadjuvant therapy vs standard therapy of locally advanced rectal cancer with high-risk factors for failure

BACKGROUND For locally advanced rectal cancer(LARC),standard therapy[consisting of neoadjuvant chemoradiotherapy(CRT),surgery,and adjuvant chemotherapy(ChT)]achieves excellent local control.Unfortunately,survival is still poor due to distant metastases,which remains the leading cause of death among these patients.In recent years,the concept of total neoadjuvant treatment(TNT)has been developed,whereby all systemic ChT-mainly affecting micrometastases-is applied prior to surgery.AIM To compare standard therapy and total neoadjuvant therapy for LARC patients with high-risk factors for failure.METHODS In a retrospective study,we compared LARC patients with high-risk factors for failure who were treated with standard therapy or with TNT.High-risk for failure was defined according to the presence of at least one of the following factors:T4 stage;N2 stage;positive mesorectal fascia;extramural vascular invasion;positive lateral lymph node.TNT consisted of 12 wk of induction ChT with capecitabine and oxaliplatin or folinic acid,fluorouracil and oxaliplatin,CRT with capecitabine,and 6-8 wk of consolidation ChT with capecitabine and oxaliplatin or folinic acid,fluorouracil and oxaliplatin prior to surgery.The primary endpoint was pathological complete response(pCR).In total,72 patients treated with standard therapy and 89 patients treated with TNT were included in the analysis.RESULTS Compared to standard therapy,TNT showed a higher proportion of pCR(23%vs 7%;P=0.01),a lower neoadjuvant rectal score(median:8.43 vs 14.98;P<0.05),higher T-and N-downstaging(70%and 94%vs 51%and 86%),equivalent R0 resection(95%vs 93%),shorter time to stoma closure(mean:20 vs 33 wk;P<0.05),higher compliance during systemic ChT(completed all cycles 87%vs 76%;P<0.05),lower proportion of acute toxicity grade≥3 during ChT(3%vs 14%,P<0.05),and equivalent acute toxicity and compliance during CRT and in the postoperative period.The pCR rate in patients treated with TNT was significantly higher in patients irradiated with intensity-modulated radiotherapy/volumetricmodulated arc radiotherapy than with 3D conformal radiotherapy(32%vs 9%;P<0.05).CONCLUSION Compared to standard therapy,TNT provides better outcome for LARC patients with high-risk factors for failure,in terms of pCR and neoadjuvant rectal score.

Extralevator abdominoperineal excision for advanced low rectal cancer:Where to go

Since its introduction,extralevator abdominoperineal excision(ELAPE)in the prone position has gained significant attention and recognition as an important surgical procedure for the treatment of advanced low rectal cancer.Most studies suggest that because of adequate resection and precise anatomy,ELAPE could decrease the rate of positive circumferential resection margins,intraoperative perforation,and may further decrease local recurrence rate and improve survival.Some studies show that extensive resection of pelvic floor tissue may increase the incidence of wound complications and urogenital dysfunction.Laparoscopic/robotic ELAPE and trans-perineal minimally invasive approach allow patients to be operated in the lithotomy position,which has advantages of excellent operative view,precise dissection and reduced postoperative complications.Pelvic floor reconstruction with biological mesh could significantly reduce wound complications and the duration of hospitalization.The proposal of individualized ELAPE could further reduce the occurrence of postoperative urogenital dysfunction and chronic perianal pain.The ELAPE procedure emphasizes precise anatomy and conforms to the principle of radical resection of tumors,which is a milestone operation for the treatment of advanced low rectal cancer.

Predictive significance of cancer related-inflammatory markers in locally advanced rectal cancer

BACKGROUND Locally advanced rectal cancer is treated using neoadjuvant chemoradiation(nCRT),followed by total mesorectal excision(TME).Tumor regression and pathological post-treatment stage are prognostic for oncological outcomes.There is a significant correlation between markers representing cancer-related inflammation,including high neutrophil-to-lymphocyte ratio(NLR),monocyteto-lymphocyte ratio(MLR),and platelet-to-lymphocyte(MLR)and unfavorable oncological outcomes.However,the predictive role of these markers on the effect of chemoradiation is unknown.AIM To evaluate the predictive roles of NLR,MLR,and PLR in patients with locally advanced rectal cancer receiving neoadjuvant chemoradiation.METHODS Patients(n=111)with locally advanced rectal cancer who underwent nCRT followed by TME at the Minimally Invasive Surgery Unit,Siriraj Hospital between 2012 and 2018 were retrospectively analyzed.The associations between post-treatment pathological stages,neoadjuvant rectal(NAR)score and the pretreatment ratios of markers of inflammation(NLR,MLR,and PLR)were analyzed.RESULTS Clinical stages determined using computed tomography,magnetic resonance imaging,or both were T4(n=16),T3(n=94),and T2(n=1).The NAR scores were categorized as high(score>16)in 23.4%,intermediate(score 8-16)in 41.4%,and low(score<8)in 35.2%.The mean values of the NLR,PLR,and MLR correlated with pathological tumor staging(ypT)and the NAR score.The values of NLR,PLR and MLR were higher in patients with advanced pathological stage and high NAR scores,but not statistically significant.CONCLUSION In patients with locally advanced rectal cancer,pretreatment NLR,MLR and PLR are higher in those with advanced pathological stage but the differences are not significantly different.

New standard in locally advanced rectal cancer

In the following review we intend to ascertain the optimal neoadjuvant therapy inpatients with locally advanced rectal cancer. In 2004, a study revealed thatchemoradiotherapy (CRT) resulted in better local control when performedpreoperatively rather than postoperatively, thus neoadjuvant treatment wasestablished as a standard treatment. Subsequently, the Polish study and the Trans-Tasman Radiation Oncology Group showed no statistically significant differencebetween concomitant CRT over 5 wk vs short-course radiotherapy (RT).Therefore, both were established as standard neoadjuvant treatments. Later, theStockholm III study demonstrated that short-course RT had a higher completepathological response than long-course RT. It also showed that a delay betweenRT and surgery presented fewer complications. This opened a window of time toprovide an early and effective systemic treatment to prevent distant metastases.Studies show that short-course RT plus oxaliplatin-based chemotherapy couldachieve this. When comparing this total neoadjuvant treatment (TNT) vsconcomitant CRT, the former showed greater complete pathological response andlower acute toxicity. Studies presented during 2020 have also shown the benefitsof TNT in terms of complete pathological response, as well as disease andmetastasis-free survival. Our review suggests that probably TNT should be thenew standard treatment for these patients. However, we will have to wait for thefull text publications of these studies to confirm this statement.

Retrospective research of neoadjuvant therapy on tumordownstaging,post-operative complications,and prognosis in locally advanced rectal cancer

BACKGROUND Neoadjuvant therapy(NAT)is becoming increasingly important in locally advanced rectal cancer.Hence,such research has become a problem.AIM To evaluate the downstaging effect of NAT,its impact on postoperative complications and its prognosis with different medical regimens.METHODS Seventy-seven cases from Shanghai Ruijin Hospital affiliated with Shanghai Jiaotong University School of Medicine were retrospectively collected and divided into the neoadjuvant radiochemotherapy(NRCT)group and the neoadjuvant chemotherapy(NCT)group.The differences between the two groups in tumor regression,postoperative complications,rectal function,disease-free survival,and overall survival were compared using theχ2 test and Kaplan-Meier analysis.RESULTS Baseline data showed no statistical differences between the two groups,whereas the NRCT group had a higher rate of T4(30/55 vs 5/22,P<0.05)than the NCT groups.Twelve cases were evaluated as complete responders,and 15 cases were evaluated as tumor regression grade 0.Except for the reduction rate of T stage(NRCT 37/55 vs NCT 9/22,P<0.05),there was no difference in effectiveness between the two groups.Preoperative radiation was not a risk factor for poor reaction or anastomotic leakage.No significant difference in postoperative complications and disease-free survival between the two groups was observed,although the NRCT group might have better long-term overall survival.CONCLUSION NAT can cause tumor downstaging preoperatively or even complete remission of the primary tumor.Radiochemotherapy could lead to better T downstaging and promising overall survival without more complications.