Current concepts in rectal cancer

Comparison of Complications and Outcomes of Very Low Anterior Resection (VLAR) Versus Intersphentric Resection (ISR) In Patients with Rectal Cancer

Background

Colorectal cancer is a cancer that starts in the colon or rectum, which are part of the digestive system. Intersphincteric resection (ISR) and very low anterior resection (VLAR) are surgical procedures used in rectal malignancy. We aimed to compare postoperative complications and recurrence after VLAR and ISR techniques in patients with rectal cancer.

Methods

In this retrospective study, 80 rectal cancer patients who underwent VLRA and ISR in Shahid Faghihi, and Abu-Ali Sina Charity Hospitals, Shiraz, Iran from 2019 to 2023 were enrolled. Eligible patients were divided into two groups based on the type of operation. One group underwent VLAR (n=40) and the second group of patients underwent ISR(n=40). Postoperative complications and outcomes were compared between the two groups.

Results

The mean age in VLAR and ISR groups was 52.8±14.3 and 54.3±11.6 years, respectively. Low anterior resection syndrome was not significantly different between the two groups (P=0.39). Postoperative fecal incontinence was observed in 27.5% and 22.5% of VLAR and ISR groups, respectively. This difference was not statistically significant (P=0.91). Rectovaginal fistula was reported in 2.5% of patients in both groups (P=0.61).

Conclusion

There was no difference in postoperative complications in VLAR and ISR techniques. Considering the lack of significant difference in the complications of the two surgical groups, it is suggested to choose the surgical method based on the location of the tumor.

Low anterior resection syndrome

Low anterior resection syndrome (LARS) is the distressful defecatory functional problem after sphincter-saving surgery for rectal cancer. Although the symptoms of fecal urgency, frequency, and incontinence may develop in most of the patients after surgery, there is no definitive treatments for LARS. Multifactorial etiologies and various risk factors have been identified, but the reduction of storage capacity in the rectum is one of the main reasons for LARS. Anal sphincter muscle or nerve damage during rectoanal resection or anastomosis construction, and intersphincteric resection for low-lying tumors or hand-sewing anastomosis, are the absolute risk factors for LARS. Preoperative radiotherapy, postoperative complications, such as anastomosis leakage, or longer duration of stoma, are also risk factors. The severity of LARS can be confirmed using the LARS score questionnaire. The questionnaire has been translated to numerous language versions including Korean and have been validated. Diverse empirical treatments, such as loperamide, fiber, probiotics, or enema, have been tried, but the safety and efficacy have not been verified yet. The 5-Hydroxytryptamine (5-HT) receptor antagonist, ramosetron, used for diarrhea-dominant irritable bowel syndrome, is one potential drug for relieving the symptoms of major LARS. A randomized-controlled trial suggested the use of ramosetron could be safe and efficacious for patients who have major LARS after sphincter-saving rectal cancer surgery. Novel techniques or drugs for relieving the symptoms of LARS should be developed more and further studies are necessary.

Laparoscopic Versus Open Pre-Treatment Loop Colostomy for Fecal Diversion in Rectal Cancer Patients: Is Laparoscopic Colostomy Better?

Diversion colostomy plays a crucial role in the management of carcinoma rectum in low- and middle-income countries as significant number of patients present with partial intestinal obstruction. The aim of this study was to compare laparoscopic and open approaches for fecal diversion done in patients with adenocarcinoma of the rectum as a pretreatment procedure. The primary end point of our study was time to initiation of neoadjuvant chemo radiation. It was a retrospective study that included all patients diagnosed to have carcinoma rectum and underwent a pretreatment fecal diversion between 2012 and 2014. A total of 55 patients underwent pretreatment diversion colostomy of which 33 were performed via the laparoscopic approach while 22 had open diversion. The time for initiation of neoadjuvant therapy was shorter in the laparoscopic group compared to the open approach (16 days vs. 20.5 days, P = 0.31). The study concluded that pretreatment diversion colostomy using the laparoscopic approach was a safe option in low- and middle-income countries as it was associated with faster recovery and early initiation of neoadjuvant therapy in patients with partially obstructed locally advanced carcinoma rectum.

Preliminary evaluation of two-row versus three-row circular staplers for colorectal anastomosis after rectal resection: a single-center retrospective analysis

PURPOSE

Circular staplers for colorectal anastomoses significantly ameliorated post-operative outcomes after rectal resection. The more recent three-row technology was conceived to improve anastomotic resistance and, thus, lower the incidence of anastomotic complications. The aim of this study was to evaluate potential advantages of three-row circular staplers (Three-CS) on anastomotic leakage (AL), stenosis (AS), and hemorrhage (AH) rates after rectal resection as compared to two-row circular staplers (Two-CS).

METHODS

All rectal resections for rectal cancer between 2016 and 2021 were retrospectively included. Patients were classified according to the circular stapler employed in Two-CS and Three-CS cohorts. AL, AS, and AH rates were compared between the two populations. Additionally, the prognostic role of the type of circular stapler on AL onset was evaluated.

RESULTS

Three-hundred and seventy-five patients underwent a rectal resection with an end-to-end anastomosis during the study period: 197 constituted the Two-CS group and 178 the Three-CS cohort. AL rate was 6.7%, significantly higher in the Two-CS group (19-9.6%) as compared to the Three-CS cohort (6-3.4%) (p = 0.01). No difference was noted in terms of AL severity. Although not statistically significant, a lower incidence rate of AL was evidenced even in the subset of patients with low rectal cancers (4.5% vs 12.5% in the two-row cohort; p = 0.33). At the multivariate analysis, Two-CS was a negative prognostic factor for AL onset (OR: 2.63; p = 0.03). No difference was noted between the two groups in terms of AS and AH.

CONCLUSION

Three-row CSs significantly decrease the rate of AL after rectal resection. Further multicenter controlled trials are still needed to confirm the advantages of three-row CSs on anastomotic complications.

Promethazine inhibits proliferation and promotes apoptosis in colorectal cancer cells by suppressing the PI3K/AKT pathway

AIM

To elucidate the potential effect of promethazine on colorectal cancer (CRC) cells and the underlying mechanism.

MATERIALS AND METHODS

Targets of the drug promethazine (PMTZ) were identified by DrugBank and comparative toxicogenomic databases (CTD), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed with STRING software. The effects of PMTZ were predicted to be associated with the PI3K/AKT pathway. Cell Counting Kit 8 (CCK-8) assays were used to evaluate the effects of different concentrations of PMTZ on the proliferation of various types of CRC cells. Flow cytometry and Western blotting analyses were used to detect the degree of CRC cell apoptosis and the expression of the apoptosis-related proteins Bcl-2, Bax and caspase-3 after PMTZ treatment. The expression levels of PI3K/AKT pathway-related proteins [PI3K, AKT, phosphorylated (P)-PI3K and p-AKT] in CRC cells treated with PMTZ were analyzed by Western blotting.

RESULTS

PMTZ inhibited the proliferation and promoted the apoptosis of CRC cells and suppressed the activation of the PI3K/AKT signaling pathway in a dose-dependent manner.

DISCUSSION AND CONCLUSIONS

PMTZ may suppress the proliferation and induce the apoptosis of CRC cells by inhibiting the PI3K/ AKT signaling pathway. This study reported, for the first time, the function of PMTZ in CRC cells and the underlying mechanism and further confirmed the potential antitumor effects of phenothiazine. The combination of bioinformatics analyses and experiments provides informative evidence for the reuse of drugs and the development of new drugs.

Hsa_circRNA_002144 promotes growth and metastasis of colorectal cancer through regulating miR-615-5p/LARP1/mTOR pathway

CircRNAs (circular RNAs), recently identified as a critical regulator in tumorigenesis, participate in CRC (colorectal cancer) growth. However, the role of hsa_circRNA_002144 in CRC was poorly understood. Firstly, hsa_circRNA_002144 showed significantly elevation in both of CRC tissues and cell lines, and suggested closely associated with poor prognosis in patients. Secondly, data from functional assays revealed that silence of hsa_circRNA_002144 inhibited CRC progression with reduced cell viability, proliferation, migration and invasion, while enhanced cell apoptosis. In addition, in vivo CRC growth and metastasis were also suppressed by knockdown of hsa_circRNA_002144. However, CRC progression was promoted with over-expression of hsa_circRNA_002144. Thirdly, hsa_circRNA_002144 colocalized with miR-615-5p in the cytoplasm of CRC cells, and decreased miR-615-5p expression. Moreover, miR-615-5p could target LARP1 (La ribonucleoprotein 1, translational regulator). Lastly, the suppressive effects of hsa_circRNA_002144 knockdown on CRC progression were reversed by LARP1 over-expression. In conclusion, hsa_circRNA_002144 could sponge miR-615-5p to promote CRC progression through the regulation of LARP1, providing a therapeutic target for cancer intervention.

Impact of BMI on Adverse Events After Laparoscopic and Open Surgery for Rectal Cancer

PURPOSE

The impact of body mass index (BMI) on outcomes after open or laparoscopic surgery for rectal cancer remains unclear. The objective of this retrospective cohort study was to examine the interaction of body mass index and surgical modality (i.e., laparoscopy versus open) with respect to short-term clinical outcomes in patients with rectal cancer.

METHODS

The ACS-NSQIP database (2012-2016) was reviewed for patients undergoing open or laparoscopic surgery for rectal cancer. The primary outcome was 30-day all-cause morbidity. Logistic regression and Cox proportional hazard models were used for analysis.

RESULTS

A total of 16,145 patients were grouped into open (N = 6759, 42%) and laparoscopic (N  = 9386, 58%) cohorts. Patients with higher BMI (p < 0.001) and those undergoing open surgery (p < 0.001) were at increased risk of all-cause morbidity. There was no significant change in the odds ratio of experiencing all-cause morbidity between open and laparoscopic surgery with increasing BMI (p = 0.572). Median length of stay was significantly shorter in the laparoscopy group (4 days vs. 6 days; p < 0.001), at the cost of increased operative time (239 min vs. 210 min, p < 0.001). The difference in operative time between laparoscopy and open surgery did not increase with rising BMI (i.e., ∆37 min vs. ∆39 min at BMI 25 kg/m² vs 50 kg/m², respectively, p = 0.491).

CONCLUSION

BMI may not be a strong modifier for surgical approach with respect to short-term clinical outcomes in patients with obesity and rectal cancer. Laparoscopic surgery was associated with improved short-term clinical outcomes, without much change in the absolute difference in operative time compared with open surgery, even at higher BMIs.

Utility of texture analysis on T2-weighted MR for differentiating tumor deposits from mesorectal nodes in rectal cancer patients, in a retrospective cohort

OBJECTIVE

The purpose of the study was to evaluate the utility of MR texture analysis for differentiating tumor deposits from mesorectal nodes in rectal cancer.

MATERIALS AND METHODS

Pretreatment MRI of 40 patients performed between 2006 and 2018 with pathologically proven tumor deposits and/or malignant nodes in the setting of rectal cancer were retrospectively reviewed. In total, 25 tumor deposits (TDs) and 71 positive lymph nodes (LNs) were analyzed for morphological and first-order texture analysis features on T2-weighted axial images. MR morphological features (lesion shape, size, signal heterogeneity, contrast enhancement) were analyzed and agreed in consensus by two experienced radiologists followed by assessment with Fisher's exact test. Texture analysis of the lesions was performed using TexRAD, a proprietary software algorithm. First-order texture analysis features (mean, standard deviation, skewness, entropy, kurtosis, MPP) were obtained after applying spatial scaling filters (SSF; 0, 2, 3, 4, 5, 6). Univariate analysis was performed with non-parametric Mann-Whitney U test. The results of univariate analysis were reassessed with generalized estimating equations followed by multivariate analysis. Using histopathology as a gold standard, diagnostic accuracy was assessed by obtaining area under the receiver operating curve.

RESULTS

MR morphological parameter, lesion shape was a strong discriminator between TDs and LNs with a p value of 0.02 (AUC: 0.76, 95% CI of 0.66 to 0.84, SE: 0.06) and sensitivity, specificity of 90% and 68%, respectively. Skewness extracted at fine filter (SSF-2) was the only significant texture analysis parameter for distinguishing TDs from LNs with p value of 0.03 (AUC: 0.70, 95% CI of 0.59 to 0.79, SE: 0.06) and sensitivity, specificity of 70% and 72%, respectively. When lesion shape and skewness-2 were combined into a single model, the diagnostic accuracy was improved with AUC of 0.82 (SE: 0.05, 95% CI of 0.72 to 0.88 with p value of < 0.01). This model also showed a high sensitivity of 91% with specificity of 68%.

CONCLUSION

Lesion shape on MR can be a useful predictor for distinguishing TDs from positive LNs in rectal cancer patients. When interpreted along with MR texture parameter of skewness, accuracy is further improved.

Surgical approach for rectal cancer: A network meta-analysis comparing open, laparoscopic, robotic and transanal TME approaches

BACKGROUND

The optimal approach for total mesorectal excision (TME) of rectal cancer remains controversial.

AIM

To compare short- and long-term outcomes after open (OpTME), laparoscopic (LapTME), robotic (RoTME) and transanal TME (TaTME).

METHODS

A systematic search of electronic databases was performed up to January 1, 2020 for randomized controlled trials (RCTs) comparing at least 2 TME strategies. A Bayesian arm-based random effect network meta-analysis (NMA) was performed, specifically, a mixed treatment comparison (MTC).

RESULTS

30 RCTs (and six updates) of 5586 patients with rectal cancer were included. No significant differences were identified in recurrence rates or survival rates. Operating time was shorter with OpTME (surface under the cumulative ranking curve [SUCRA] 0.96) compared to LapTME, RoTME and TaTME. Although OpTME was associated with the most blood loss (SUCRA 0.90) and had a slower recovery with increased length of stay (SUCRA 0.90) compared to the minimally invasive techniques, there was no difference in postoperative morbidity. OpTME was associated with a more complete TME specimen compared to LapTME (Risk Ratio [RR] 1.05, 95% Credible Interval [CrI] 1.01, 1.11), and TaTME had less involved CRMs (RR 0.173, 95% CrI 0.02, 0.76) versus LapTME. There were no differences between the modalities in terms of deep TME defects, DRM distance, or lymph node yield.

CONCLUSIONS

While OpTME was the most effective TME modality for short term histopathological resection quality, there was no difference in long-term oncologic outcomes. Minimally invasive approaches enhance postoperative recovery, at the cost of longer operating times. Technique selection should be based on individual tumour characteristics and patient expectations, as well as surgeon and institutional expertise.

Survival following rectal cancer surgery: does the age matter?

Introduction: Information regarding rectal cancer surgery outcomes and survival benefits in the elderly is sparse. Radical rectal surgery can be associated with substantial morbidity and mortality. We investigated age-specific survival for patients undergoing radical rectal surgery to determine outcomes in elderly patients Methods: Over a 10-year period data on all patients who underwent rectal cancer surgery was performed. Patients were grouped according to age and eight other variables including cancer stage (Duke's/TNM). Data analysed using computer program R. Kaplan-Meier survival curves estimated for age groups and compared using a modified log-rank permutation test. Survival curves fitted using Cox proportional hazard models and hazard ratios obtained Results: About 374 patients underwent surgery. Survival percentages at 1 year by age group are 91.3% for age <50, and 75.5% for age >80. At 5 years these are 87.0% for age <50 and 57.1% for >80. Overall the variation among the survival curves for the age groups is significant (p < .001). The hazard ratio for over the 80+ with the age group <50 as the reference is 4.79 (95% CI: 1.44-15.92) and is significant (p = .011) Conclusion: Overall survival is significantly less in the elderly. There is a striking reduction in survival in >80 year olds in the first post-operative year. This study highlights that care must be taken in deciding whether radical surgery should be offered to those patients and careful consideration is given to allow the best overall survival and quality of life.

Cost-Effectiveness Analysis of Total Neoadjuvant Therapy Followed by Radical Resection Versus Conventional Therapy for Locally Advanced Rectal Cancer

BACKGROUND

Definitive surgery with total mesorectal excision is the mainstay of treatment for locally advanced rectal cancer. Multimodality therapy improves long-term survival. Current standards advise neoadjuvant chemoradiation followed by radical surgery and adjuvant chemotherapy. Nationally, compliance with adjuvant chemotherapy is only 32%. New research evaluates the effectiveness of total neoadjuvant therapy: complete chemotherapy and chemoradiation before surgery.

OBJECTIVE

The aim of this study is to determine the favored treatment for locally advanced rectal cancer by comparing the cost-effectiveness of total neoadjuvant therapy and the current standard of care.

DESIGN

Decision analytical modeling using long-term costs and 5-year disease-free survival was performed to determine the cost-effectiveness after total neoadjuvant therapy and the current standard of care. Sensitivity analysis was used to investigate the effect of uncertainty in model parameters.

SETTINGS

Centers for Medicare & Medicaid Services billing data perspective was adopted and outcomes modeled according to local and national databases and literature consensus.

PATIENTS

Adult patients with stage II or III rectal cancer were selected.

MAIN OUTCOME MEASURES

Cost-effectiveness in disease-free life-years, incremental cost-effectiveness ratio, and net monetary benefit were determined over a 5-year posttreatment period. The favored strategy was determined based on cost-effectiveness and sensitivity analyses.

RESULTS

Cost-effectiveness for total neoadjuvant therapy was 40,708 $/life-year, and, for conventional therapy, cost-effectiveness was 44,248 $/life-year. Sensitivity analysis showed that, for an estimated total neoadjuvant therapy completion rate of 90%, total neoadjuvant therapy would remain the dominant strategy for any adjuvant chemotherapy completion rate of less than 93%.

LIMITATIONS

The samples used to calculate completion rates are small, and survival probabilities are based on existing literature, local database values, and consensus estimates. The model encompasses a 5-year time period from diagnosis.

CONCLUSIONS

Cost-effectiveness analysis shows that a strategy of total neoadjuvant therapy followed by radical surgery is favored over the current standard of care for locally advanced rectal cancer. Sensitivity analysis shows that a low rate of adjuvant chemotherapy administration plays a key role in decreasing the cost-effectiveness of the current standard of care. See Video Abstract at http://links.lww.com/DCR/A942.

A dual-perspective analysis of the hospital and payer-borne burdens of selected in-hospital surgical complications in low anterior resection for colorectal cancer

OBJECTIVES

The economic burden of surgical complications is borne in distinctly different ways by hospitals and payers. This study quantified the incidence and economic burden - from both the hospital and payer perspective - of selected major colorectal surgery complications in patients undergoing low anterior resection (LAR) for colorectal cancer.

METHODS

Retrospective, observational study of patient undergoing LAR for colorectal cancer between 1/1/2010 and 7/1/2015. Analyses were replicated in two large healthcare administrative databases: Premier (hospital discharge and billing data; hospital perspective) and Optum (insurance claims data; payer perspective). Multivariable analyses evaluated the association between infection (surgical site or bloodstream), anastomotic leak, and bleeding complications and the following outcomes: hospital length of stay (LOS), non-home discharge, 90-day all-cause readmission, index admission costs to the hospital, index admission payer expenditures, and index admission +90-day post-discharge payer expenditures.

RESULTS

9,738 eligible LAR patients were included (7,479 in Premier; 2,259 in Optum). Overall, the incidences of infection, anastomotic leak, and bleeding complications were 6.4%, 10.6%, and 10.9%, respectively, during the index hospitalization. Each complication was associated with statistically significant longer LOS, higher risk of non-home discharge, higher risk of 90-day readmission, greater costs to the hospital, and higher payer expenditures.

CONCLUSIONS

In-hospital infection, anastomotic leak, and bleeding were associated with a substantial economic burden, for both hospitals and payers, in patients undergoing LAR for colorectal cancer. This study provides information which may be used to quantify the potential economic value and impact of innovations in surgical care and delivery that reduce the incidence and burden of these complications.

The evolution of pelvic dissection for rectal cancer from blunt dissection to total mesorectal excision

"Modern" rectal cancer treatment began in the 18th century. However, initial results of the pioneer surgeons were very poor. During the next several decades, significant progress was made towards the cure of rectal cancer. Improvements have included lowering mortality, reducing recurrence, and optimizing functional outcomes. This article reviews the individuals and their advancements in rectal cancer treatment. It describes the changes in the surgical approach for tumor resection, the study of the lymphatic spread of rectal cancer and the advances in sphincter preservation procedures from the era of blunt dissection until the paradigm changing revolution of total mesorectal excision.

Long non-coding RNA TCF7 predicts the progression and facilitates the growth and metastasis of colorectal cancer

Long non-coding RNA (lnc)TCF7 has been reported to promote the self‑renewal of human cancer stem cells, and enhance the aggressiveness of human non‑small cell lung cancer and hepatocellular carcinoma cells. However, the effect of lncTCF7 on colorectal cancer (CRC) tumorigenesis and progression is currently unclear. In the present study, reverse transcription‑quantitative polymerase chain reaction results demonstrated that lncTCF7 expression was higher in CRC tissues compared with adjacent normal tissues and was significantly associated with tumor size, differentiation degree, tumor‑node‑metastasis grade, lymph node metastasis and invasion depth. In addition, lncTCF7 demonstrated a high sensitivity and specificity for diagnosing CRC, as determined by receiver operating characteristic curve analysis. Furthermore, lncTCF7 silencing in SW‑620 and HT29 CRC cell lines inhibited the proliferation, cell cycle, migration and invasion of cells, as determined by Cell Counting Kit‑8 assays, propidium iodide (PI) staining and flow cytometry, wound healing assays and Transwell invasion assays, respectively; however, Annexin V/PI double staining and flow cytometry indicated that lncTCF7 silencing did not significantly affect the apoptosis of CRC cells. These results indicate that lncTCF7 may predict the progression, and promote the growth and metastasis, of CRC, and may therefore be a novel diagnostic marker and therapeutic target for CRC treatment.

Association between neoadjuvant chemoradiation and survival for patients with locally advanced rectal cancer

AIM

To examine the overall survival differences for the following neoadjuvant therapy modalities - no therapy, chemotherapy alone, radiation alone and chemoradiation - in a large cohort of patients with locally advanced rectal cancer.

METHOD

Adults with clinical Stage II and III rectal adenocarcinoma were selected from the National Cancer Database and grouped by type of neoadjuvant therapy received: no therapy, chemotherapy only, radiotherapy only or chemoradiation. Multivariable regression methods were used to compare adjusted differences in perioperative outcomes and overall survival.

RESULTS

Among 32 978 patients included, 9714 (29.5%) received no neoadjuvant therapy, 890 (2.7%) chemotherapy only, 1170 (3.5%) radiotherapy only and 21 204 (64.3%) chemoradiation. Compared with no therapy, chemotherapy or radiotherapy alone were not associated with any adjusted differences in surgical margin positivity, permanent colostomy rate or overall survival (all P > 0.05). With adjustment, neoadjuvant chemoradiation vs no therapy was associated with a lower likelihood of surgical margin positivity (OR 0.74, P < 0.001), decreased rate of permanent colostomy (OR 0.77, P < 0.001) and overall survival [hazard ratio (HR) 0.79, P < 0.001]. When compared with chemotherapy or radiotherapy alone, chemoradiation remained associated with improved overall survival (vs chemotherapy alone HR 0.83, P = 0.04; vs radiotherapy alone HR 0.83, P < 0.019).

CONCLUSION

Neoadjuvant chemoradiation, not chemotherapy or radiotherapy alone, is important for sphincter preservation, R0 resection and survival for patients with locally advanced rectal cancer. Despite this finding, one-third of patients in the United States with locally advanced rectal cancer fail to receive stage-appropriate chemoradiation.

Long noncoding RNA ZEB1-AS1 expression predicts progression and poor prognosis of colorectal cancer

BACKGROUND

ZEB1-AS1 acts as an oncogene in hepatocellular carcinoma, accelerating tumor growth and promoting metastasis. However, its roles in colorectal cancer (CRC) remain unclear.

METHODS

In this study, we determined the expression of ZEB1-AS1 in CRC tissues by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, we investigated the relationship between various clinicopathological features of CRC patients and ZEB1-AS1 expression, and evaluated the diagnostic and prognostic value of ZEB1-AS1 in CRC.

RESULTS

We found that ZEB1-AS1 expression was significantly higher in CRC tissues than in adjacent normal colorectal tissues. Moreover, its expression was significantly correlated with tumor size, differentiation degree, TNM grade, metastasis, depth of invasion and Dukes' classification, but not with sex, age, location and organization. In addition, at the optimal cutoff value of 2.340, the values of diagnostic sensitivity and specificity amounted to 63.0% and 90.7%, respectively, with an area under the curve (AUC) of 0.846 (95% CI, 0.797-0.895). Finally, CRC patients of the high ZEB1-AS1 expression group had a poorer prognosis and a significantly lower survival rate than those of the low expression group, and Cox regression analysis indicated that ZEB1-AS1 expression and metastasis were independent predictors of poor prognosis.

CONCLUSIONS

Our data suggest that ZEB1-AS1 has no obvious early diagnostic value, but it may be utilized as a new prognostic biomarker for CRC.

Ostomy telehealth for cancer survivors: Design of the Ostomy Self-management Training (OSMT) randomized trial

PURPOSE

An ostomy adversely affects health-related quality of life (HRQOL) in a diverse population of cancer survivors and their caregivers. Hit-or-miss ostomy care, nurse counseling, and community referral have been the primary modes of self-management education and support in the peri-operative setting. Few evidence-based, systematic ostomy self-management programs are available to ensure optimal post-operative care. This paper describes the study design of a telehealth-based Ostomy Self-management Training (OSMT) program for cancer survivors and their caregivers.

METHODS

The study is a three-year, randomized trial that tests the effectiveness of the OSMT program on survivor activation, self-efficacy, and HRQOL. The intervention integrates goal setting and problem-solving approaches to enhance survivor activation and self-efficacy to carry out ostomy care. The curriculum is delivered via four group sessions administered by trained ostomy certified nurses (WOCNs) and peer ostomates. An additional session is offered to caregivers to address their needs in relation to ostomy care. Telehealth approaches through videoconferencing are used to enhance program delivery to participants in three different geographic areas across two time zones. Participants join sessions via real-time videoconferencing from their homes.

CONCLUSIONS

The OSMT program has high potential to make a positive impact on the unique physical, psychological, social, and spiritual needs of cancer survivors living with a permanent ostomy. The study design, process, and telehealth approach contributes to the success of future dissemination efforts of the intervention into diverse clinical and community settings.

Adjuvant Chemotherapy After Preoperative Chemoradiation Improves Survival in Patients With Locally Advanced Rectal Cancer

BACKGROUND

Practice guidelines differ in their support of adjuvant chemotherapy use in patients who received preoperative chemoradiation for rectal cancer.

OBJECTIVE

The purpose of this study was to evaluate the impact of adjuvant chemotherapy among patients with locally advanced rectal cancer who received neoadjuvant chemoradiation and surgery.

DESIGN

This was a retrospective study. Multivariable Cox proportional hazard modeling was used to evaluate the adjusted survival differences.

SETTINGS

Data were collected from the National Cancer Database.

PATIENTS

Adults with pathologic stage II and III rectal adenocarcinoma who received neoadjuvant chemoradiation and surgery were included.

MAIN OUTCOME MEASURES

Overall survival was measured.

RESULTS

Among 12,696 patients included, 4023 (32%) received adjuvant chemotherapy. The use of adjuvant chemotherapy increased over the study period from 23% to 36%. Although older age and black race were associated with a lower likelihood of receiving adjuvant chemotherapy, patients with higher education level and stage III disease were more likely to receive adjuvant chemotherapy (all p < 0.05). At 7 years, overall survival was improved among patients who received adjuvant chemotherapy (60% vs. 55%; p < 0.001). After risk adjustment, the use of adjuvant chemotherapy was associated with improved survival (HR = 0.81 (95% CI, 0.72-0.91); p < 0.001). In the subgroup of patients with stage II disease, survival was also improved among patients who received adjuvant chemotherapy (68% vs 58% at 7 y; p < 0.001; HR = 0.70 (95% CI, 0.57-0.87); p = 0.002). Among patients with stage III disease, the use of adjuvant chemotherapy was associated with a smaller but persistent survival benefit (56% vs 51% at 7 y; p = 0.017; HR = 0.85 (95% CI, 0.74-0.98); p = 0.026).

LIMITATIONS

The study was limited by its potential for selection bias and inability to compare specific chemotherapy regimens.

CONCLUSIONS

The use of adjuvant chemotherapy among patients with rectal cancer who received preoperative chemoradiation conferred a survival benefit. This study emphasizes the importance of adjuvant chemotherapy in the management of rectal cancer and advocates for its increased use in the setting of neoadjuvant therapy. See Video Abstract at http://link.lww.com/DCR/A428.

Melatonin synergizes the chemotherapeutic effect of 5-fluorouracil in colon cancer by suppressing PI3K/AKT and NF-κB/iNOS signaling pathways

5-Fluorouracil (5-FU) is one of the most commonly used chemotherapeutic agents in colon cancer treatment, but has a narrow therapeutic index limited by its toxicity. Melatonin exerts antitumor activity in various cancers, but it has never been combined with 5-FU as an anticolon cancer treatment to improve the chemotherapeutic effect of 5-FU. In this study, we assessed such combinational use in colon cancer and investigated whether melatonin could synergize the antitumor effect of 5-FU. We found that melatonin significantly enhanced the 5-FU-mediated inhibition of cell proliferation, colony formation, cell migration and invasion in colon cancer cells. We also found that melatonin synergized with 5-FU to promote the activation of the caspase/PARP-dependent apoptosis pathway and induce cell cycle arrest. Further mechanism study demonstrated that melatonin synergized the antitumor effect of 5-FU by targeting the PI3K/AKT and NF-κB/inducible nitric oxide synthase (iNOS) signaling. Melatonin in combination with 5-FU markedly suppressed the phosphorylation of PI3K, AKT, IKKα, IκBα, and p65 proteins, promoted the translocation of NF-κB p50/p65 from the nuclei to cytoplasm, abrogated their binding to the iNOS promoter, and thereby enhanced the inhibition of iNOS signaling. In addition, pretreatment with a PI3K- or iNOS-specific inhibitor synergized the antitumor effects of 5-FU and melatonin. Finally, we verified in a xenograft mouse model that melatonin and 5-FU exerted synergistic antitumor effect by inhibiting the AKT and iNOS signaling pathways. Collectively, our study demonstrated that melatonin synergized the chemotherapeutic effect of 5-FU in colon cancer through simultaneous suppression of multiple signaling pathways.

The clinical value and biological function of PTTG1 in colorectal cancer

Pituitary tumor transforming gene-1 (PTTG1) has been suggested to serve as an oncogene in several types of human tumors, but little is known about the biological function of PTTG1 in colorectal cancer. PTTG1 mRNA and protein expressions in colorectal cancer tissues and cell lines were measured by qRT-PCR, western blot or immunohistochemistry. The association between PTTG1 protein expression and clinicopathological features was analyzed. The function of PTTG1 on colorectal cancer cell proliferation and metastasis were explored through MTT, colony formation, migration and invasion assays. In our results, PTTG1 mRNA and protein expressions were increased in colorectal cancer tissues and cell lines compared with normal colonic tissues and colon epithelial cell line. PTTG1 overexpression positively associated with clinical stage, T classification, N classification, M classification and differentiation. The univariate and multivariate analyses suggested PTTG1 overexpression was an independent poor prognostic factor for colorectal cancer patients. The in vitro experiments showed knocking down PTTG1 inhibited colorectal cancer growth and metastasis. In conclusion, PTTG1 is an independent prognostic factor and acts as an oncogene in colorectal cancer.

Thymoquinone potentiates chemoprotective effect of Vitamin D3 against colon cancer: a pre-clinical finding

Prevention of colon cancer among high-risk group has been long lasting research goal. Emerging data have evidenced the anticancer activities of Vitamin D3 (Vit.D) and Thymoquinone (TQ). The aim of the current study was to evaluate the synergistic potential of Thymoquinone and Vitamin D3 in the control of colon cancer progression using azoxymethane-induced rat model. Vit.D and TQ were given individually or in combination 4 week prior to induction and continued for a total of 20 week. At the end of the study, all animals were euthanized and their resected colons were examined macroscopically and microscopically for tumor growth. Colonic tissue preparations were used for measuring gene expression and/or protein levels of selected pro and anti-tumor biomarkers using quantitative RT-PCR, ELISA and immunohistochemistry. Compared with their individual supplementation, combined Vit.D/TQ showed prominent anti-tumor effect manifested by significant reduction (P < 0.05) of the numbers of grown tumors and large aberrant crypts foci. Mechanistically, gene expression and/or protein quantification studies revealed that combined Vit.D/TQ supplementation induced significant reduction (P < 0.01 and P < 0.05) of pro-cancerous molecules (Wnt, β-catenin, NF-κB, COX-2, iNOS, VEGF and HSP-90) as well as significant increase (P < 0.01 and P < 0.05, respectively) of anti-tumorigenesis biomarkers (DKK-1, CDNK-1A, TGF-β1, TGF-β/RII and smad4) as compared to un-supplemented or individually supplemented groups, respectively. In conclusion, TQ augmented the chemopreventive effect of Vit.D during the initiation phase of colon cancer in rat model, with the potential to suppress progression of pre-neoplastic lesions in colon carcinogenesis.

Overexpression of LARP1 predicts poor prognosis of colorectal cancer and is expected to be a potential therapeutic target

This study investigated the significance of La-related protein 1 (LARP1) in the development and progression of colorectal cancer (CRC). Quantitative real-time polymerase chain reaction and Western blot analyses were carried out to determine the mRNA and protein expression of LARP1 in CRC tumor tissues and paired adjacent normal mucosa. The expression of LARP1 was upregulated in CRC. Immunohistochemical analysis using tissue microarray was performed. A positive correlation between LARP1 and proliferating cell nuclear antigen (PCNA) in the area of proliferation was observed using the Spearman's correlation coefficient test (r = 0.332, P < 0.01). The elevated expression of LARP1 significantly correlated with T stage (P = 0.02), N stage (P = 0.006), M stage (P < 0.001), American Joint Committee on Cancer (AJCC) stage (P = 0.04), differentiation rank (P < 0.001), and PCNA level (P < 0.001). In addition, the inhibitory effect of LARP1 knockdown on CRC cell proliferation was demonstrated using Cell Counting Kit-8 (CCK8) and colony-forming cell (CFC) assays. Multivariate analysis showed that LARP1 was an independent prognostic factor for overall survival (OS; hazard rate (HR) = 0.244; 95 % confidence interval (CI), 0.078-0.769; P = 0.016) and disease-free survival (DFS; HR = 0.281; 95 % CI, 0.086-0.917; P = 0.035) in CRC patients. LARP1 plays an important role in the proliferation of colorectal cancer and represents a new prognostic indicator.

Vitamin D3 enhances the tumouricidal effects of 5-Fluorouracil through multipathway mechanisms in azoxymethane rat model of colon cancer

BACKGROUND

Vitamin D3 and its analogues have recently been shown to enhance the anti-tumour effects of 5- Fluorouracil (5-FU) both in vitro and in xenograft mouse model of colon cancer. This study measured the potential mechanism(s) by which vitamin D3 could synergise the tumouricidal activities of 5-FU in azoxymethane (AOM) rat model of colon cancer.

METHODS

Seventy-five male Wistar rats were divided equally into 5 groups: Control, AOM, AOM-treated by 5-FU (5-FU), AOM-treated by vitamin D3 (VitD3), and AOM-treated by 5-FU + vitamin D3 (5-FU/D). The study duration was 15 weeks. AOM was injected subcutaneously for 2 weeks (15 mg/kg/week). 5-FU was injected intraperitoneally in the 9th and 10th weeks post AOM (8 total injections were given: 12 mg/kg/day for 4 successive days, then 6 mg/kg every other day for another 4 doses) and oral vitamin D3 (500 IU/rat/day; 3 days/week) was given from week 7 post AOM till the last week of the study. The colons were collected following euthanasia for gross and histopathological examination. The expression of β-catenin, transforming growth factor-β1 (TGF-β1), TGF-β type 2 receptor (TGF-βR2), smad4, inducible nitric oxide synthase (iNOS), and heat shock protein-90 (HSP-90) proteins was measured by immunohistochemistry. In colonic tissue homogenates, quantitative RT-PCR was used to measure the mRNA expression of Wnt, β-catenin, Dickkopf-1 (DKK-1) and cyclooxygenase-2 (COX-2) genes, while ELISA was used to measure the concentrations of TGF-β1, HSP-90 and COX-2 proteins.

RESULTS

Monotherapy with 5-FU or vitamin D3 significantly decreased the number of grown tumours induced by AOM (P < 0.05); however, their combination resulted in more significant tumouricidal effects (P < 0.05) compared with monotherapy groups. Mechanistically, vitamin D3/5-FU co-therapy significantly decreased the expression of Wnt, β-catenin, iNOS, COX-2 and HSP-90 and significantly increased the expression of DKK-1, TGF-β1, TGF-βR2, smad4 (P < 0.05), in comparison with their corresponding monotherapy groups.

CONCLUSIONS

Vitamin D3 and 5-FU synergise together and exhibit better anticancer effects by modulating Wnt/β-catenin pathway, TGF-β1 signals, iNOS, COX-2 and HSP-90. Further studies are required to illustrate the clinical value of vitamin D supplementation during the treatment of colon cancer with 5-FU in human patients.