GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms:A Chinese multicenter study of 12-year experience

BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)using data from a large cohort.METHODS Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in China.Random forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival,and two nomograms were constructed.RESULTS A total of 1408 patients with R-NENs were included.Tumor grade,T stage,tumor size,age,and a prognostic nutritional index were important risk factors for prognosis.The GATIS score was calculated based on these five indicators.For overall survival prediction,the respective C-indexes in the training set were 0.915(95%confidence interval:0.866-0.964)for overall survival prediction and 0.908(95%confidence interval:0.872-0.944)for progression-free survival prediction.According to decision curve analysis,net benefit of the GATIS score was higher than that of a single factor.The time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time periods.CONCLUSION The GATIS score had a good predictive effect on the prognosis of patients with R-NENs,with efficacy superior to that of the World Health Organization grade and TNM stage.

Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms

This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the analysis.The diagnosis and depth assessment of EUS was compared to the histology findings.The prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior specificity.EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision.

Enhancing prognostic accuracy in predicting rectal neuroendocrine neoplasms

The recently published retrospective study introduces the GATIS score,a new predictive model for rectal neuroendocrine neoplasms.By analyzing data from a large Chinese multicenter cohort,the study shows that the GATIS score,incor-porating tumor grade,T stage,tumor size,age,and prognostic nutritional index,demonstrates superior predictive power for overall survival and progression-free survival compared to traditional World Health Organization grade and tumor,nodes and metastases staging systems.This editorial aims to discuss the impor-tance of the GATIS score,its potential impact on clinical practice,and the strengths and limitations of the study.Finally,it explores the significance,methodology,and clinical implications of these findings.

Postoperative chemoradiotherapy with capecitabine and oxaliplatin vs.capecitabine for pathological stage N2 rectal cancer

Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response without benefit to survival.In this study,we further explored the role of these two postoperative CRT regimens in patients with pathological stage N2 rectal cancer.Methods:This study was a subgroup analysis of a randomized clinical trial.A total of 180 patients with pathological stage N2 rectal cancer were eligible,85 received capecitabine with radiotherapy(RT),and 95 received capecitabine and oxaliplatin with RT.Patients in both groups received adjuvant chemotherapy[capecitabine and oxaliplatin(XELOX);or fluorouracil,leucovorin,and oxaliplatin(FOLFOX)]after CRT.Results:At a median follow-up of 59.2[interquartile range(IQR),34.0−96.8]months,the three-year diseasefree survival(DFS)was 53.3%and 64.9%in the control group and the experimental group,respectively[hazard ratio(HR),0.63;95%confidence interval(95%CI),0.41−0.98;P=0.04].There was no significant difference between the groups in overall survival(OS)(HR,0.62;95%CI,0.37−1.05;P=0.07),the incidence of locoregional recurrence(HR,0.62;95%CI,0.24−1.64;P=0.33),the incidence of distant metastasis(HR,0.67;95%CI,0.42−1.06;P=0.09)and grade 3−4 acute toxicities(P=0.78).For patients with survival longer than 3 years,the conditional overall survival(COS)was significantly better in the experimental group(HR,0.39;95%CI,0.16−0.96;P=0.03).Conclusions:Our results indicated that adding oxaliplatin to capecitabine-based postoperative CRT is safe and effective in patients with pathological stage N2 rectal cancer.

Advances in radiotherapy and targeted therapies for rectal cancer

The last decade witnessed a significant progress in understanding the biology and immunology of colorectal cancer alongside with the technical innovations in radiotherapy.The stepwise implementation of intensitymodulated and image-guided radiation therapy by means of megavolt computed tomography and helical tomotherapy enabled us to anatomically sculpt dose delivery,reducing treatment related toxicity.In addition,the administration of a simultaneous integrated boost offers excellent local control rates.The novel challenge is the development of treatment strategies for medically inoperable patient and organ preserving approaches.However,distant control remains unsatisfactory and indicates an urgent need for biomarkers that predict the risk of tumor spread.The expected benefit of target?ed therapies that exploit the tumor genome alone is so far hindered by high cost techniques and pharmaceuticals,hence hardly justifying rather modest improvements in patient outcomes.On the other hand,the immune landscape of colorectal cancer is now better clarified with regard to the immunosuppressive network that promotes immune escape.Both N2 neutrophils and myeloid-derived suppressor cells(MDSC)emerge as useful clinical biomarkers of poor prognosis,while the growing list of anti-MDSC agents shows promising ability to boost antitumor T-cell immunity in preclinical settings.Therefore,integration of genetic and immune biomarkers is the next logical step towards effective targeted therapies in the context of personalized cancer treatment.

Systematic review of ablative therapy for the treatment of renal allograft neoplasms

BACKGROUND To date,there are no guidelines on the treatment of solid neoplasms in the transplanted kidney.Historically,allograft nephrectomy has been considered the only reasonable option.More recently,nephron-sparing surgery (NSS) and ablative therapy (AT) have been proposed as alternative procedures in selected cases.AIM To review outcomes of AT for the treatment of renal allograft tumours.METHODS We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 Checklist.PubMed was searched in March 2019 without time restrictions for all papers reporting on radiofrequency ablation (RFA),cryoablation (CA),microwave ablation (MWA),high-intensity focused ultrasound (HIFU),and irreversible electroporation (IRE) of solid tumours of the kidney allograft.Only original manuscripts describing actual cases and edited in English were considered.All relevant articles were accessed in full text.Additional searches included all pertinent references.Selected studies were also assessed for methodological quality using a tool based on a modification of the Newcastle Ottawa scale.Data on recipient characteristics,transplant characteristics,disease characteristics,treatment protocols,and treatment outcomes were extracted and analysed.Given the nature and the quality of the studies available (mostly retrospective case reports and small retrospective uncontrolled case series),a descriptive summary was provided.RESULTS Twenty-eight relevant studies were selected describing a total of 100 AT procedures in 92 patients.Recipient age at diagnosis ranged from 21 to 71 years whereas time from transplant to diagnosis ranged from 0.1 to 312 mo.Most of the neoplasms were asymptomatic and diagnosed incidentally during imaging carried out for screening purposes or for other clinical reasons.Preferred diagnostic modality was Doppler-ultrasound scan followed by computed tomography scan,and magnetic resonance imaging.Main tumour types were: papillary renal cell carcinoma (RCC) and clear cell RCC.Maximal tumour diameter ranged from 5 to 55 mm.The vast majority of neoplasms were T1a N0 M0 with only 2 lesions staged T1b N0 M0.Neoplasms were managed by RFA (n = 78),CA (n = 15),MWA (n = 3),HIFU (n = 3),and IRE (n = 1).Overall,3 episodes of primary treatment failure were reported.A single case of recurrence was identified.Follow-up ranged from 1 to 81 mo.No cancer-related deaths were observed.Complication rate was extremely low (mostly < 10%).Graft function remained stable in the majority of recipients.Due to the limited sample size,no clear benefit of a single procedure over the other ones could be demonstrated.CONCLUSION AT for renal allograft neoplasms represents a promising alternative to radical nephrectomy and NSS in carefully selected patients.Properly designed clinical trials are needed to validate this therapeutic approach.

Radical radiotherapy without surgical tumor resection for rectal cancer

In this editorial,I would like to comment on the article,recently published in the World Journal of Clinical Oncology.The article focuses on non-surgical treatments for locally recurrent rectal cancer,including the watch-and-wait(WW)strategy after total neoadjuvant therapy(TNT)and particle beam therapy.As treatment options for rectal cancer continue to evolve,the high complete response rate achieved with TNT has led to the development of a new non-surgical approach:WW.Chemoradiotherapy followed by consolidation chemotherapy,in particular,has a low rate of tumor growth and is a treatment aimed at achieving a cure without surgery.However,the risk of recurrence within two years is significant,necessitating careful follow-up.Establishing standardized follow-up methods that can be implemented by many physicians is essential.Carbon ion radiotherapy has demonstrated high local control with a low incidence of severe late toxicities,even after previous pelvic radiotherapy.While these new non-surgical curative treatments for rectal cancer require further investigation,future advancements in this field are anticipated.

Evaluating the clinical application and effect of acupuncture therapy in anal function rehabilitation after low-tension rectal cancer surgery

BACKGROUND According to the indexes of serum and anal function,acupuncture therapy was applied to patients with low rectal cancer in order to avoid the occurrence of anal incontinence and reduce complications.AIM To explore the clinical application and evaluate the effect of acupuncture therapy for anal function rehabilitation after low-tension rectal cancer surgery.METHODS From the anorectal surgery cases,we selected 120 patients who underwent colorectal cancer surgery between January 2020 and December 2022 and randomly divided them into a control group(n=60),observation group(n=60),and control group after surgery for lifestyle intervention(including smoking cessation and exercise),dietary factor adjustment,anal movement,and oral loperamide treatment.The serum levels of motilin,5-hydroxytryptamine,and vasoactive intestinal peptide(VIP),Wexner score for anal incontinence,and incidence of complications were compared between groups.RESULTS After treatment,the VIP and 5-hydroxytryptamine levels in the observation group were lower than those in the control group(P<0.05).The motilin level was higher than that in the control group(P<0.05).Postoperative anal incontinence was better in the observation group than in the control group(P<0.05).The incidence of complications in the observation group was 6.67%,which was significantly lower than that in the control group(21.67%;P<0.05).CONCLUSION Acupuncture therapy has a positive effect on the rehabilitation of anal function after low-tension rectal cancer surgery;it can effectively help to improve the serum indices of patients,avoid the occurrence of anal incontinence,and reduce the incidence of complications.Popularizing and applying it will be valuable.

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.

Azacitidine maintenance therapy for blastic plasmacytoid dendritic cell neoplasm allograft: A case report

BACKGROUND Blastic plasmacytoid dendritic cell neoplasm(BPDCN)is a rare,highly invasive malignant neoplasm.There is no universally accepted standard of care because of its rarity and the dearth of prospective research.It is still challenging for some patients to achieve persistent clinical remission or cure,despite the success of allogeneic hematopoietic stem cell transplantation(allo-HSCT),indicating that there is still a significant recurrence rate.We report a case of prevention of BPDCN allograft recurrence by azacitidine maintenance therapy and review the relevant literature.CASE SUMMARY We report a 41-year-old man with BPDCN who was admitted to hospital due to skin sclerosis for>5 mo’duration.BPDCN was diagnosed by combined clinical assessment and laboratory examinations.Following diagnosis,the patients underwent induction consolidation chemotherapy to achieve the first complete remission,followed by bridging allo-HSCT.Post-transplantation,azacitidine(75 mg/m2 for 7 d)was administered as maintenance therapy,with repeat administration every 4–6 wk and appropriate extension of the chemotherapy cycle.After 10 cycles,the patient has been disease free for 26 mo after transplantation.Regular assessments of bone marrow morphology,minimal residual disease,full donor chimerism,Epstein–Barr virus,and cytomegalovirus all yielded normal results with no abnormalities detected.CONCLUSION Azacitidine may be a safe and effective maintenance treatment for BPDCN following transplantation because there were no overt adverse events during the course of treatment.

Effects of fluid therapy combined with a preoperative glucose load regimen on postoperative recovery in patients with rectal cancer

BACKGROUND Patients with rectal cancer undergoing radical resection often have poor post-operative recovery due to preoperative fasting and water deprivation and the removal of diseased tissue,and have a high risk of complications.Therefore,it is of great significance to apply appropriate rehydration regimens to patients un-dergoing radical resection of rectal cancer during the perioperative period to improve the postoperative outcomes of patients.AIM To analyze the effects of goal-directed fluid therapy(GDFT)with a preoperative glucose load regimen on postoperative recovery and complications in patients undergoing radical resection for rectal cancer.METHODS Patients with rectal cancer who underwent radical resection(n=184)between January 2021 and December 2023 at our hospital were randomly divided into either a control group or an observation group(n=92 in each group).Both groups received a preoperative glucose load regimen,and routine fluid replacement and GDFT were additionally implements in the control and observation groups,res-pectively.The operative conditions,blood levels of lactic acid and inflammatory markers,postoperative recovery,cognitive status,hemodynamic indicators,brain oxygen metabolism,and complication rates were compared between the groups.RESULTS The colloidal fluid dosage,total infusion,and urine volume,as well as time to first exhaust,time to food intake,and postoperative length of hospital stay,were lower in the observation group(P<0.05).No significant differences were observed between the two groups in terms of operation time,bleeding volume,crystalloid liquid consumption,time to tracheal extubation,complication rate,heart rate,or mean arterial pressure(P>0.05).Compared with the control group,in the ob-servation group the lactic acid level was lower immediately after the surgery(P<0.05);the Mini-Mental State Examination score was higher on postoperative day 3(P<0.05);the pulse pressure variability(PPV)was lower at 30 min after pneumoperitoneum(P<0.05),though the differences in the PPV of the two groups was not significant at the remaining time points(P>0.05);tumor necrosis factor-αand interleukin-6 levels were lower on postoperative day 3(P<0.05);and the left and right regional cerebral oxygen saturation was higher immediately after the surgery and 30 min after pneumoperitoneum(P<0.05).CONCLUSION GDFT combined with the preoperative glucose load regimen is a safe and effective treatment strategy for im-proving postoperative recovery and risk of complications in patients with rectal cancer undergoing radical re-section.

Transanal Endoscopic Microsurgery (TEM) for Rectal Neoplasms

Introduction: The abdominal approach for the treatment of rectal tumors is associated with a considerable rate of morbidity. Transanal Endoscopic Microsurgery (TEM) is an alternative technique that is less invasive than radical surgery, and therefore has a lower associated morbidity. Moreover, with proper patient selection, TEM presents oncological outcomes comparable to radical surgery. The aim of this study is to review our results obtained with TEM and discuss its role in the treatment of malignant rectal lesions. Patients and Methods: A prospective descriptive study from June 2008 until February 2011. The indications for TEM were: early rectal neoplastic lesions (T1N0M0) with good prognostic factors;neoplastic lesions in more advanced stages in selected patients (high surgical risk, refusal of radical surgery or stoma, and palliative intention). Results: Resection by TEM was performed on 19 patients. The average hospital stay was 5.7 days with an associated morbidity of 16.7%. R0 resection was 88.8%. During the follow-up of 15 (3 - 31) months, no recurrence has been shown. Conclusions: TEM is a safe and effective procedure for the treatment of selected early malignant rectal lesions and is associated with low morbidity. It is a therapeutic strategy based on a multidisciplinary team, careful patient selection, an audited surgical technique and a strict follow-up protocol.

Liver-directed therapies for liver metastases from neuroendocrine neoplasms:Can laser ablation play any role?

Aggressive cytoreduction can prolong survival in patients with unresectable liver metastases(LM)from neuroendocrine neoplasms(NEN),and minimally invasive,liver-directed therapies are gaining increasing interest.Catheter-based treatments are used in disseminated disease,whereas ablation techniques are usually indicated when the number of LM is limited.Although radiofrequency ablation(RFA)is by far the most used ablative technique,the goal of this opinion review is to explore the potential role of laser ablation(LA)in the treatment of LM from NEN.LA uses thinner needles than RFA,and this is an advantage when the tumors are in at-risk locations.Moreover,the multi-fiber technique enables the use of one to four laser fibers at once,and each fiber provides an almost spherical thermal lesion of 12-15 mm in diameter.Such a characteristic enables to tailor the size of each thermal lesion to the size of each tumor,sparing the liver parenchyma more than any other liver-directed therapy,and allowing for repeated treatments with low risk of liver failure.A recent retrospective study reporting the largest series of LM treated with LA documents both safety and effectiveness of LA,that can play a useful role in the multimodality approach to LM from NEN.

Experimental study on effect of recombinant human growth hormone combined with chemotherapy on stomach neoplasms implanted in nude mice

Objective: To investigate the effect of different doses of recombined growth hormone (rhGH) on stomach neo- plasms implanted in nude mice, and its efficacy in combining with chemotherapy (flurouracil, 5-FU). Methods: Human stom- ach neoplasms model was established in nude mice. The nude mice were divided into control group, moderate-dose of rhGH group, low-dose rhGH group, 5-FU group, moderate-dose rhGH/5-FU group, and low-dose rhGH/5-FU group. The results of each group were observed after ten days. Results: After therapy, the body mass of rhGH groups was significantly increased compared with control group (P<0.05), the body mass of rhGH/5-FU groups was significantly increased compared with 5-FU group (P<0.05), but it was no significant difference between rhGH/5-FU groups and control group (P>0.05). The average tumor mass and volume of rhGH groups were not significantly increased compared with control group (P>0.05), but they were significantly reduced in 5-FU group and rhGH/5-FU groups (P<0.05). They were no significant difference between rhGH/5- FU groups and 5-FU group (P>0.05). After treatment, the percentages of S, G0/G1 and G2/M phases and proliferation index (PI) were not significantly changed in rhGH groups compared with control group (P>0.05), and the same with rhGH/5-FU groups compared with 5-FU group (P>0.05). The difference caused by dose of rhGH was not significant. Conclusion: rhGH enhances body mass, does not stimulate tumor growth, and has no adverse effects on tumor bearing nude mice. Combined with flurouracil, rhGH does not influence the efficacy of chemotherapy, and has no effect on tumor cell cycle kinetics.

Favorable response after radiation therapy for intraductal papillary mucinous neoplasms manifesting as acute recurrent pancreatitis:A case report

BACKGROUND There has been an increasing number of elderly patients with intraductal papillary mucinous neoplasm(IPMN),who are surgically intolerant and require less invasive treatment options,which are limited.In the present study,we report a case of IPMN presenting with acute recurrent pancreatitis(ARP),in which radiation therapy effectively prevented further attacks of ARP and reduced tumor volume.CASE SUMMARY An 83-year-old man was referred to our hospital with an asymptomatic incidental pancreatic cyst.Endoscopic ultrasound imaging and magnetic resonance cholangiopancreatography revealed a multiloculated tumor in the head of the pancreas,with dilated pancreatic ducts and mural nodules.The patient was diagnosed with mixed-type IPMN,and five years later,he developed ARP.Several endoscopic pancreatic ductal balloon dilatations failed to prevent further ARP attacks.Surgery was considered clinically inappropriate because of his old age and comorbidities.He was referred to our department for radiation therapy targeted at those lesions causing intraductal hypertension and radiation was administered at a dose of 50 Gy.An magnetic resonance imaging scan taken ten weeks after treatment revealed a decrease in tumor size and improvement of pancreatic duct dilatation.Fourteen months later,he remains symptom-free from ARP.CONCLUSION This case highlights the important role of radiation therapy in mitigating the signs and symptoms of ARP in patients with inoperable IPMN.

Impact of technology on indications and limitations for transanal surgical removal of rectal neoplasms

Transanal surgery has and continues to be well accepted for local excision of benign rectal disease not amenable to endoscopic resection. More recently, there has been increasing interest in applying transanal surgery to local resection of early malignant disease. In addition, some groups have started utilizing a transanal route in order to accomplish total mesorectal excision(TME) for more advanced rectal malignancies. We aim to review the role of various transanal and endoscopic techniquesin the local resection of benign and malignant rectal disease based on published trial data. Preliminary data on the use of transanal platforms to accomplish TME will also be highlighted. For endoscopically unresectable rectal adenomas, transanal surgery remains a widely accepted method with minimal morbidity that avoids the downsides of a major abdomino-pelvic operation. Transanal endoscopic microsurgery and transanal minimally invasive surgery offer improved visualization and magnification, allowing for finer and more precise dissection of more proximal and larger rectal lesions without compromising patient outcome. Some studies have demonstrated efficacy in utilizing transanal platforms in the surgical management of early rectal malignancies in selected patients. There is an overall higher recurrence rate with transanal surgery with the concern that neither chemoradiation nor salvage surgery may compensate for previous approach and correct the inferior outcome. Application of transanal platforms to accomplish transanal TME in a natural orifice fashion are still in their infancy and currently should be considered experimental. The current data demonstrate that transanal surgery remains an excellent option in the surgical management of benign rectal disease. However, care should be used when selecting patients with malignant disease. The application of transanal platforms continues to evolve. While the new uses of transanal platforms in TME for more advanced rectal malignancy are exciting, it is important to remain cognizant and not sacrifice long term survival for short term decrease in morbidity and improved cosmesis.

How reliable is current imaging in restaging rectal cancer after neoadjuvant therapy?

In patients with advanced rectal cancer,neoadjuvant chemo radiotherapy provides tumor downstaging and downsizing and complete pathological response in up to 30%of cases.After proctectomy complete pathological response is associated with low rates of local recurrence and excellent long term survival.Several authors claim a less invasive surgery or a non operative policy in patients with partial or clinical complete response respectively,however to identify patients with true complete pathological response before surgical resection remains a challenge.Current imaging techniques have been reported to be highly accurate in the primary staging of rectal cancer,however neoadjuvant therapy course produces deep modifications on cancer tissue and on surrounding structures such as overgrowth fibrosis,deep stroma alteration,wall thickness,muscle disarrangement,tumor necrosis,calcification,and inflammatory infiltration.As a result,the same imaging techniques,when used for restaging,are far less accurate.Local tumor extent may be overestimated or underestimated.The diagnostic accuracy of clinical examination,rectal ultrasound,computed tomography,magnetic resonance imaging,and positron emission tomography using 18F-fluoro-2’-deoxy-Dglucose ranges between 25%and 75%being less than 60%in most studies,both for rectal wall invasion and for lymph nodes involvement.In particular the ability to predict complete pathological response,in order to tailor the surgical approach,remains low.Due to the radio-induced tissue modifications,combined with imaging technical aspects,low rate accuracy is achieved,making modern imaging techniques still unreliable in restaging rectal cancer after chemo-radiotherapy.

Neoadjuvant radiotherapy for rectal cancer management

Thirty per cent of all colorectal tumours develop in the rectum.The location of the rectum within the bony pelvis and its proximity to vital structures presents significant therapeutic challenges when considering neoadjuvant options and surgical interventions.Most patients with early rectal cancer can be adequately managed by surgery alone.However,a significant proportion of patients with rectal cancer present with locally advanced disease and will potentially benefit from down staging prior to surgery.Neoadjuvant therapy involves a variety of options including radiotherapy,chemotherapy used alone or in combination.Neoadjuvant radiotherapy in rectal cancer has been shown to be effective in reducing tumour burden in advance of curative surgery.The gold standard surgical rectal cancer management aims to achieve surgical removal of the tumour and all draining lymph nodes,within an intact mesorectal package,in order to minimise local recurrence.It is critically important that all rectal cancer cases are discussed at a multidisciplinary meeting represented by all relevant specialties.Pre-operative staging including CT thorax,abdomen,pelvis to assess for distal disease and magnetic resonance imaging to assess local involvement is essential.Staging radiology and MDT discussion are integral in identifying patients who require neoadjuvant radiotherapy.While Neoadjuvant radiotherapy is potentially beneficial it may also result in morbidity and thus should be reserved for those patients who are at a high risk of local failure,which includes patients with nodal involvement,extramural venous invasion and threatened circumferential margin.The aim of this review is to discuss the role of neoadjuvant radiotherapy in the management of rectal cancer.

Gene therapy for human colorectal carcinoma using human CEA promoter controlled bacterial ADP-ribosylating toxin genes:PEA and DTA gene transfer

AIM To establish a tissue-specific gene therapy for colorectal carcinoma using bacterial ADP-ribosylating toxin genes.METHODS Pseudomonas exotoxin A domain Ⅱ+Ⅲ (PEA) was cloned from genomic DNA of Pseudomonas aeruginosa. PEA and diphtheria toxin A chain gene (DTA) were modified to express eukaryotically. After sequencing, the toxin genes under the control of human carcinoembryonic antigen (CEA) promoter were cloned into retroviral vectors to construct CEAPEA and CEADTA respectively. In vitro cotransfection of the constructs with luciferase vectors and in vivo gene transfer in nude mice were subsequently carried out.RESULTS Both CEAPEA and CEADTA specifically inhibited the reporter gene expression in the CEA positive human colorectal carcinoma (CRC) cells in vitro. Direct injection of CEAPEA and CEADTA constructs into the established human tumors in BALB/c nude mice led to significant and selective reductions in CRC tumor size as compared with that in control groups.CONCLUSION The toxin genes, working as therapeutic genes, are suitable for the tissue-specific gene therapy for colorectal carcinoma.

Prediction of pathological nodal stage of locally advanced rectal cancer by collective features of multiple lymph nodes in magnetic resonance images before and after neoadjuvant chemoradiotherapy

Objective:To predict pathological nodal stage of locally advanced rectal cancer by a radiomic method that uses collective features of multiple lymph nodes(LNs)in magnetic resonance images before and after neoadjuvant chemoradiotherapy(NCRT).Methods:A total of 215 patients were included in this study and chronologically divided into the discovery cohort(n=143)and validation cohort(n=72).In total,2,931 pre-NCRT LNs and 1,520 post-NCRT LNs were delineated from all visible rectal LNs in magnetic resonance images.Geometric,first-order and texture features were extracted from each LN before and after NCRT.Collective features are defined as the maximum,minimum,mean,median value and standard deviation of each feature from all delineated LNs of each participant.LN-model is constructed from collective LN features by logistic regression model with L1 regularization to predict pathological nodal stage(ypN0 or ypN+).Tumor-model is constructed from tumor features for comparison by using DeLong test.Results:The LN-model selects 7 features from 412 LN features,and the tumor-model selects 7 features from 82 tumor features.The area under the receiver operating characteristic curve(AUC)of LN-model in the discovery cohort is 0.818[95%confidence interval(95%CI):0.745-0.878],significantly(Z=2.09,P=0.037)larger than 0.685(95%CI:0.602-0.760)of the tumor-model.The AUC of LN-model in validation cohort is 0.812(95%CI:0.703-0.895),significantly(Z=3.106,P=0.002)larger than 0.517(95%CI:0.396-0.636)of the tumor-model.Conclusions:The usage of collective features from all visible rectal LNs performs better than the usage of tumor features for the prediction of pathological nodal stage of locally advanced rectal cancer.