Total neoadjuvant therapy in rectal cancer: the evidence and expectations

An overview of potential of natural compounds to regulate epigenetic modifications in colorectal cancer: a recent update

Colorectal cancer (CRC) remains an alarming global health concern despite advancements in treatment modalities over recent decades. Among the various factors contributing to CRC, this review emphasizes the critical role of epigenetic mechanisms in its pathogenesis and progression. This review also describes the potential role of natural compounds in altering the epigenetic landscape, focused mainly on DNA methylation, histone modification, and non-coding RNAs. Publications from the previous five years were searched and retrieved using well-known search engines and databases like PubMed, Google Scholar, and ScienceDirect. Keywords like CRC/colorectal cancer, CAC/Colitis associated CRC, inflammasomes, epigenetic modulation, genistein, curcumin, quercetin, resveratrol, anthocyanins, sulforaphane, and epigallocatechin-3-gallate were used in various combinations during the search. These natural compounds predominantly affect pathways such as Wnt/β-catenin, NF-κB, and PI3K/AKT to suppress CRC cell proliferation and oxidative stress and enhance anti-inflammation and apoptosis. However, their clinical use is restricted due to their low bioavailability. However, multiple methods exist to overcome challenges like this, including but not limited to structural modifications, nanoparticle encapsulations, bio-enhancers, and novel advanced delivery systems. These methods improve their potential as supportive therapies that target CRC progression epigenetically with fewer side effects. Current research focuses on enhancing epigenetic targeting to control CRC progression while minimizing side effects, emphasizing improved specificity, bioavailability, and efficacy as standalone or synergistic therapies.

CHI3L1 mediates radiation resistance in colorectal cancer by inhibiting ferroptosis via the p53/SLC7A11 pathway

BACKGROUND

Radiotherapy is a key treatment for colorectal cancer (CRC), particularly rectal cancer; however, many patients are resistant to radiation. While it has been shown that CHI3L1 is associated with CRC progression, its specific function and regulatory mechanisms in radiation resistance remain unclear.

METHODS

The levels of CHI3L1 in CRC and normal tissue samples were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. To assess the effects of CHI3L1 on CRC cell proliferative, migratory, and invasive capacities, Cell Counting Kit-8 (CCK-8) and Transwell assays were performed. Radiation resistance in CRC cells with varying CHI3L1 expression levels was evaluated through colony formation assay. Western blot and immunofluorescence analyses were conducted to explore the correlation between CHI3L1 and p53 expression levels. Ferroptosis was assessed by determining reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) concentrations in cells with different CHI3L1 expression levels, and a xenograft mouse model was used to identify the molecular mechanisms of ferroptosis in vivo.

RESULTS

Significant CHI3L1 upregulated was observed in CRC tissues and was associated with promotion of malignant cell behaviors. The number of colonies in CHI3L1-overexpressing groups was significantly greater than that in the control groups following radiation, indicating increased radiation resistance in the former group. Furthermore, CHI3L1 overexpression was associated with p53 downregulation and elevated p53 ubiquitination. Notably, CHI3L1 inhibited the ferroptosis of CRC cells by suppressing p53 expression through the p53/SLC7A11 signaling pathway.

CONCLUSIONS

CHI3L1 overexpression promotes the proliferation, migration, invasion, and radiation resistance of CRC cells. Elevated CHI3L1 expression is associated with increased p53 ubiquitination and SLC7A11 upregulation. CHI3L1 promotes radiation resistance by suppressing ferroptosis in CRC cells through the p53/SLC7A11 axis.

Prognostic Nutritional Index as a Predictor of Surgical Morbidity in Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer

Background: The management of locally advanced rectal cancer (LARC) has seen the emergence of total neoadjuvant therapy (TNT) as a promising approach. TNT has shown potential in enhancing tumor regression, increasing pathological complete response (pCR) rates, and improving the control of systemic disease. However, the impact of TNT on complications during and after surgery remains uncertain. This research aimed to assess surgical complications linked to TNT in comparison with conventional neoadjuvant chemoradiotherapy (nCRT). Additionally, this study explored the potential of the Prognostic Nutritional Index (PNI) as a predictor of surgical outcomes. Methods: A retrospective cohort study was conducted at Sancaktepe Şehit Prof. Dr. İlhan Varank Training and Research Hospital, including patients with LARC who underwent either TNT or nCRT followed by curative excision (TME). Demographic data, perioperative complications, and tumor-related variables were also analyzed. The prognostic value of the PNI in predicting surgical complications was assessed using multivariate logistic regression analysis. Statistical significance was set at p < 0.05. Results: A total of 103 patients with LARC were included, of whom 38 (36.9%) received TNT and 65 (63.1%) underwent nCRT. TNT was associated with significantly higher rates of anastomotic leakage (13.2% vs. 6.2%, p = 0.04) and wound infections (23.7% vs. 9.2%, p = 0.02). The mean tumor size was significantly smaller in the TNT group (3.22 ± 1.10 cm) than in the nCRT group (3.65 ± 1.26 cm, p = 0.02). The PNI was significantly lower in the TNT group (38.96 ± 5.54) than in the nCRT group (41.31 ± 4.65, p = 0.03). Multivariate logistic regression analysis demonstrated that a lower PNI was independently associated with increased surgical complications (β = -1.09, p = 0.028, 95% CI: -2.06--0.12). Conclusions: Although TNT demonstrates clear oncological benefits in LARC, it is associated with increased perioperative morbidity. Our findings suggest that the PNI is a valuable predictive biomarker of surgical complications in patients treated with TNT. Preoperative nutritional assessment and optimization may improve perioperative outcomes and mitigate the risks associated with TNT. Future prospective studies should explore targeted interventions to enhance the safety profile of TNT while preserving its oncological advantages.

A battle of surgical strategies: Clinically enlarged lateral lymph nodes in patients with locally advanced rectal cancer; extended mesorectal excision (e-TME) versus traditional surgery (TME-alone) a meta-analysis

BACKGROUND

The infiltration of lateral lymph nodes (LLN) plays a crucial role in the staging and treatment of individuals with locally advanced rectal cancer (LARC). This meta-analysis aimed to compare the efficacy of extended mesorectal excision (eTME) versus traditional mesorectal excision (TME-alone) in patients with clinically enlarged (LLN) concomitant neoadjuvant chemoradiation.

METHODS

This study is registered with PROSPERO (CRD42023457805). A comprehensive literature search was conducted across PubMed/Medline, Scopus, Cochrane Library, EMBASE, Web of Science, and EBSCO databases for comparative studies published until June 2024. The study included patients with clinically enlarged LLN concomitant with neoadjuvant chemoradiation in rectal cancer who underwent either eTME or TME alone. Primary outcomes included local recurrence (LR), lateral local recurrence (LLR), overall survival (OS), distant metastasis, and disease-free survival (DFS).

RESULTS

The pooled mean for LR was 6.6 % in the TME group and 4.8 % in the eTME group, with no significant difference between the groups (OR, 0.569; 95 % CI, 0.180-1.792; P = 0.33). Similarly, the pooled LLR rates were 38.5 % for TME and 55.8 % for eTME, indicating a higher recurrence rate in the eTME group (P = 0.65). In the term of the (OS) rates were 93.7 % for TME and 93.2 % for eTME, with no significant difference (P = 0.56). The (DFS) rates were 84.6 % for TME and 86 % for eTME, with no significant difference (P = 0.38). Additionally, the distant recurrence rates were 6.8 % for TME and 17.5 % for eTME, with no significant difference (P = 0.479).

CONCLUSION

Our meta-analysis provides reliable information on the efficacy of eTME versus TME-alone in patients with clinically enlarged LLN concomitant with nCRT in rectal cancer, as we addressed previous limitations for a more accurate comparison. While the (eTME) does not show significant oncologic benefits over (TME alone), the study emphasizes the need for careful patient selection and further research to refine treatment guidelines. Individual patient- and tumor characteristics should guide the most appropriate surgical strategy.

Exploring the Impact of Chemotherapy on the Emergence of Antibiotic Resistance in the Gut Microbiota of Colorectal Cancer Patients

With nearly half of colorectal cancer (CRC) patients diagnosed at advanced stages where surgery alone is insufficient, chemotherapy remains a cornerstone for this cancer treatment. To prevent infections and improve outcomes, antibiotics are often co-administered. However, chemotherapeutic interactions with the gut microbiota cause significant non-selective toxicity, affecting not only tumor and normal epithelial cells but also the gut microbiota. This toxicity triggers the bacterial SOS response and loss of microbial diversity, leading to bacterial mutations and dysbiosis. Consequently, pathogenic overgrowth and systemic infections increase, necessitating broad-spectrum antibiotics intervention. This review underscores how prolonged antibiotic use during chemotherapy, combined with chemotherapy-induced bacterial mutations, creates selective pressures that drive de novo antimicrobial resistance (AMR), allowing resistant bacteria to dominate the gut. This compromises the treatment efficacy and elevates the mortality risk. Restoring gut microbial diversity may mitigate chemotherapy-induced toxicity and improve therapeutic outcomes, and emerging strategies, such as fecal microbiota transplantation (FMT), probiotics, and prebiotics, show considerable promise. Given the global threat posed by antibiotic resistance to cancer treatment, prioritizing antimicrobial stewardship is essential for optimizing antibiotic use and preventing resistance in CRC patients undergoing chemotherapy. Future research should aim to minimize chemotherapy's impact on the gut microbiota and develop targeted interventions to restore microbial diversity affected during chemotherapy.

Neoadjuvant chemotherapy and chemoradiotherapy versus chemoradiotherapy alone in high-risk locally advanced rectal cancer: A retrospective comparison of two Dutch tertiary referral centres

INTRODUCTION

The effect of neoadjuvant chemotherapy and chemoradiotherapy in patients with locally advanced rectal cancer, at increased risk of failing current treatment regimens, is unknown. This study compared the complete response rate and long-term survival of these patients treated with or without neoadjuvant chemotherapy prior to chemoradiotherapy.

MATERIALS AND METHODS

Patients with high-risk locally advanced rectal cancer, who were surgically treated or entered a watch and wait approach after neoadjuvant chemoradiotherapy with or without neoadjuvant chemotherapy in Erasmus Medical Centre or Catharina Hospital between 2016 and 2020, were retrospectively identified. High-risk was defined as the presence of tumour invasion into the mesorectal fascia, grade 4 extramural venous invasion, enlarged lateral lymph nodes, or tumour deposits. The primary endpoint was complete response rate, which was defined as a histopathological complete response or a sustained (during 12 months) clinical complete response. Long-term oncological outcomes were evaluated based on Kaplan-Meier and Cox regression survival analyses.

RESULTS

The neoadjuvant chemotherapy group consisted of 64 patients, of whom 61 (95.3 %) were treated with chemotherapy prior to chemoradiotherapy, the chemoradiotherapy group of 194 patients. The complete response rates were 25.0 % and 9.8 %, respectively (P = 0.002). The estimated 3-year overall survival was 92.2 % in the neoadjuvant chemotherapy group versus 66.9 % in the chemoradiotherapy group.

CONCLUSION

Excellent oncological outcomes were observed in patients with high-risk locally advanced rectal cancer selected during a multidisciplinary team (MDT) meeting for neoadjuvant chemotherapy and chemoradiotherapy. The actual difference with patients treated with chemoradiotherapy alone should be investigated in prospective trials. Pretreatment referral to expert MDTs is encouraged.

Does Total Neoadjuvant Therapy Impact Surgical Precision in Total Mesorectal Excision? A Nationwide Survey of the Experiences of Expert Surgeons

BACKGROUND

The treatment of locally advanced rectal cancer (LARC) has steadily progressed over the past four decades, with recent focus shifting towards total neoadjuvant therapy (TNT). This survey aims to elucidate the perceived surgical challenges faced by Austrian colorectal surgeons performing total mesorectal excision (TME), focusing on the increased complexity and surgical difficulty introduced by intensified treatment regimens.

METHODS

A comprehensive survey was conducted among Austrian colorectal surgeons to explore various aspects of managing and performing TME following TNT. The survey included questions on the general management of LARC within their institutions and utilized a five-point Likert scale to assess the respondents' perceptions and experiences regarding surgical precision and post-operative morbidity associated with TNT.

RESULTS

A total of 31 surgeons (54% response rate) completed the survey. Regarding multidisciplinary therapy preferences, 56% of respondents preferred conventional neoadjuvant therapy regimens, with 32% favoring chemoradiotherapy and 24% opting for short-course radiotherapy, while 31% chose TNT. The majority of respondents (65%) reported quality differences in tissue dissection during TME following TNT, with 57% experiencing difficulties in identifying tissue planes and 47% noting increased tissue fragility. Increased bleeding was reported by 32% of respondents. In cases of regrowth after a watch-and-wait approach, 64% observed quality changes in tissue dissection, and 47% noted tissue fragility.

CONCLUSIONS

The survey results indicate that TNT impairs surgical precision due to changes in tissue quality and challenges in identifying surgical planes. Given the critical importance of surgical precision in achieving low local recurrence rates in mid-to-low LARC, these challenges could significantly impact patient outcomes. Further prospective studies are required to elucidate the extent of these effects.

A management of patients achieving clinical complete response after neoadjuvant therapy and perspectives: on locally advanced rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME) and selective use of adjuvant chemotherapy is currently considered the standard of care for locally advanced rectal cancer (LARC). Despite this, the concept of organ preservation is gradually challenging this approach. The management of complete clinical remission (cCR) lacks international consensus, leading scholars to develop their own perspectives based on well-designed studies and long-term data from large multicenter cohorts. To ensure appropriate treatment, this review focuses on the choice of neoadjuvant therapy, criteria for defining cCR, and treatment strategies for patients who achieve cCR after neoadjuvant therapy. By providing guidance on the accurate management of LARC patients after cCR, this review aims to prevent over- or under-treatment.

Postoperative urinary dysfunction following lateral lymph node dissection for rectal cancer via minimally invasive surgery

BACKGROUND

Lateral lymph node dissection (LLND) for locally advanced rectal cancer (LARC) is performed widely since it reduces local recurrence. However, there are some disadvantages to LLND, including technical difficulties and association with postoperative urinary dysfunction. Procedures for LARC have also become more minimally invasive: laparoscopic surgery (LS) has become more common, and use of robot-assisted LS (RALS) is increasing. The purpose of this study is to assess differences in postoperative urinary dysfunction after LLND for LARC between LS and RALS, and to identify risk factors for postoperative urinary dysfunction.

METHODS

The subjects were 100 patients with LARC (≥ cT3) with the inferior border of the tumor reaching the peritoneal reflection who underwent LS or RALS with LLND between 2009 and 2023 at Juntendo University Hospital. After LLND, the urinary catheter was usually removed on or before postoperative day 5. The duration of urinary catheterization (DUC) was used to evaluate postoperative urinary dysfunction. The standard (S) and long-term (L) groups were defined as cases with urinary catheter removal at ≤ 5 and > 5 days, respectively. DUC was examined for LS vs. RALS and clinicopathological factors were identified that adversely affect DUC.

RESULTS

Of the 100 subjects, 72 underwent LS and 28 received RALS. LLND was bilateral in 65 cases and unilateral in 35 cases. The median DUC was 5 days, with 74 cases in group S and 26 in group L. The most frequent postoperative complication (Clavien-Dindo Grade 2 or higher) was urinary dysfunction, followed by ileus and surgical site infection (SSI), and none differed by procedure (LS vs. RALS). Univariate analysis showed significant differences in LLND laterality (p = 0.02) and SSI (p = 0.04) between groups S and L. In multivariate analysis, bilateral LLND (p < 0.01, HR 7.37) and SSI (p = 0.01, HR 15.36) were independent factors that worsened DUC.

CONCLUSIONS

There was no difference in urinary dysfunction after LLND between LS and RALS. Bilateral LLND and SSI were risk factors for lengthening DUC. Compared to bilateral LLND, unilateral LLND can reduce urinary dysfunction; therefore, selective LLND, which is overwhelmingly unilateral LLND, and prevention of perioperative SSI may be important for maintenance of urinary function.

A randomized phase 3 trial of total neoadjuvant therapy (induction chemotherapy, neoadjuvant chemoradiation, neoadjuvant chemotherapy, and surgery) vs. standard long-term chemoradiation therapy (neoadjuvant chemoradiation, surgery, and adjuvant chemotherapy) in locally advanced rectal cancer

Purpose

The management of rectal adenocarcinoma has evolved during the last decade, shifting from a conventional neoadjuvant chemoradiotherapy, surgery, and adjuvant chemotherapy in all cases to a total neoadjuvant approach, especially in locally advanced tumors when a sphincter-sparing surgery has been planned. However, the exact indications and the neoadjuvant regimen with the highest response remain unresolved. We aimed to assess whether administering neoadjuvant chemotherapy before and after preoperative chemoradiotherapy could increase the pathological complete response (pCR) rates.

Methods

We conducted a phase 3, multicenter, randomized trial at four hospitals in Iran. Adult patients with a newly diagnosed, biopsy-proven, locally advanced non-metastatic rectal adenocarcinoma with an ECOG performance status of 0-2 were randomly assigned (2:2) to either the total neoadjuvant treatment (TNT) or the standard-of-care groups using a block randomized design. Investigators and participants were not masked to treatment allocation and groups. The TNT group received neoadjuvant chemotherapy with FOLFOX6 (intravenous 85 mg/m2 oxaliplatin and 400 mg/m2 leucovorin, followed by intravenous 400 mg/m2 fluorouracil bolus and then continuous infusion at a dose of 2,400 mg/m2 over 46 h every 14 days for four cycles before and four cycles after chemoradiotherapy), chemoradiotherapy (50.4 Gy during 28 fractions and 800 mg/m2 concurrent oral capecitabine twice daily 5 days per week), and total mesorectal excision. The standard-of-care group received neoadjuvant chemoradiotherapy, total mesorectal excision, and adjuvant chemotherapy (eight cycles). The primary endpoint was the pathological complete response. Safety analyses were conducted on treated patients.

Results

Overall, 25 and 27 patients were enrolled in the TNT and standard-of-care groups, respectively. Both groups were similar in terms of gender, age, and tumor differentiation. The tumors in the standard-of-care group were significantly located closer to the anal verge compared with those in the TNT group (9.4 ± 3.7 cm in TNT vs. 6.8 ± 4 cm in standard, p = 0.02). A pCR was reached in 48% (12/25) and 25.9% (7/27) of patients in the TNT and standard-of-care groups, respectively (p = 0.4). The R0 resection rates were identical between the two groups (92% vs. 88.9%, p = 0.3). Moreover, the toxicity rates were similar between the two groups.

Conclusion

Our results showed that TNT is a safe and feasible treatment approach in patients with rectal cancer and may improve the overall pCR rate compared with standard treatment.

Clinical trial registration

https://irct.behdasht.gov.ir/trial/65666, identifier IRCT20220723055527N1.

The role of PIK3CA gene mutations in colorectal cancer and the selection of treatment strategies

PIK3CA gene encodes the p110α catalytic subunit of PI3K, which regulates the PI3K/AKT/mTOR signaling pathway. PIK3CA gene mutation is one of the most common mutations in colorectal cancer (CRC), affecting about 15%-20% of CRC patients. PIK3CA gene mutation leads to the persistent activation of the PI3K/AKT/mTOR signaling pathway, which promotes the proliferation, invasion, metastasis, and drug resistance of CRC. This article provides a summary of the key detection methods for PIK3CA gene mutation, and provides an introduction to the existing colorectal cancer treatments and their practical applications in the clinic. Besides, this article summarizes the role and mechanism of PIK3CA gene mutation in the occurrence and development of CRC. It also explores the relationship between PIK3CA gene mutation and the clinical features and prognosis of CRC. This article focuses on the influence and mechanism of PIK3CA gene mutation on the targeted therapy and immunotherapy of CRC, and discusses the potential value and future direction of PIK3CA gene mutation in the personalized therapy of CRC. We aim to provide new perspectives and ideas for the precise diagnosis and treatment of CRC.

Can yStage Ⅰ/Ⅱ rectal cancer patients be treated in the same way as stage Ⅰ/Ⅱ patients?

Background

Neoadjuvant therapy (NAT) before radical surgery are effective treatments for locally advanced rectal cancer. However, the treatment strategy after NAT and surgery is still unclear. It is difficult to accurately evaluate the stage before NAT, as some cases are downstaged by NAT.

Objective

We investigated the treatment strategies based on the postoperative pathology of patients with yStage Ⅰ or Ⅱ rectal cancer who underwent NAT and radical resection.

Design

They patients were retrospectively evaluated the long-term outcomes. They were divided into patients with yStage I/II receiving NAT and patients with stage I/II patients without NAT (non-NAT). Disease-free survival (DFS) and overall survival (OS) were examined, and the prognosis was compared. Cox proportional hazard model was used to examine the recurrence risk factors in all patients or NAT. We compared the effects of adjuvant therapy in NAT.

Patients

Overall, 521 patients histologically diagnosed with yStage I/II or stage I/II who underwent surgery for rectal cancer between April 2001 and July 2019 were eligible.

Results

The NAT and non-NAT groups included 80 and 441 patients, respectively. DFS was significantly lower in NAT, but there was no difference in OS between the two groups. All patients had several recurrence risk factors, but none of the NAT had such risk factors. No significant difference in DFS and OS was found between NAT with and without adjuvant chemotherapy.

Limitation

This is a single-center retrospective study.

Conclusions

NAT had lower DFS than non-NAT, but no difference in OS was observed. No significant recurrence risk factors were observed in NAT. Adjuvant chemotherapy for NAT may have no benefit.

Pelvic exenteration for locally advanced rectal cancer and associated outcomes in England between 1995 and 2016: Analysis of a national database

AIM

The clinical burden of pelvic exenteration (PE) for locally advanced rectal cancer (LARC) is nationally under-reported. The widespread use of pelvic MRI since 2005 has increased the accuracy of local staging and awareness of the need for 'beyond TME (total mesorectal excision)' surgery. The aim of this study was to assess the volume of patients undergoing PE within England, which factors affected survival outcomes and whether the use of MRI has influenced these outcomes.

METHOD

The volume of patients undergoing PE and associated survival outcomes across England between 1995 and 2016 was evaluated from Public Health England Hospital Episode Statistics data.

RESULTS

A total of 2996 patients were recorded as undergoing PE. The 5-year overall survival rate improved after 2005 compared with prior to 2005 (61.7% vs. 37%, p < 0.001), with no significant difference between cancer registries throughout England. After 2005, the volume of patients undergoing PE and undergoing preoperative MRI increased, as did the number of non-T4 cancers operated on. After 2005, age, preoperative MRI and preoperative radiotherapy were the significant factors influencing 5-year overall survival on multivariate analysis.

CONCLUSION

This review of national data confirms that PE outcomes are under-reported. MRI staging aids with the identification of patients suitable for perioperative treatment, surgery or palliation and facilitates treatment planning. Since 2005, MRI, likely in combination with advances in surgery and perioperative treatment, has improved survival outcomes. It is imperative that detailed information from patients with LARC undergoing PE is captured and reported in order to optimize care and future service provision.

A nomogram of anastomotic stricture after rectal cancer: a retrospective cohort analysis

BACKGROUND

Anastomotic stricture significantly impacts patients' quality of life and long-term prognosis. However, current clinical practice lacks accurate tools for predicting anastomotic stricture. This study aimed to develop a nomogram to predict anastomotic stricture in patients with rectal cancer who have undergone anterior resection.

METHODS

A total of 1542 eligible patients were recruited for the study. Least absolute shrinkage selection operator (Lasso) analysis was used to preliminarily select predictors. A prediction model was constructed using multivariate logistic regression and presented as a nomogram. The performance of the nomogram was evaluated using receiver operating characteristic (ROC) curves, calibration diagrams, and decision curve analysis (DCA). Internal validation was conducted by assessing the model's performance on a validation cohort.

RESULTS

72 (4.7%) patients were diagnosed with anastomotic stricture. Participants were randomly divided into training (n = 1079) and validation (n = 463) sets. Predictors included in this nomogram were radiotherapy, diverting stoma, anastomotic leakage, and anastomotic distance. The area under the ROC curve (AUC) for the training set was 0.889 [95% confidence interval (CI) 0.840-0.937] and for the validation set, it was 0.930 (95%CI 0.879-0.981). The calibration curve demonstrated a strong correlation between predicted and observed outcomes. DCA results showed that the nomogram had clinical value in predicting anastomotic stricture in patients after anterior resection of rectal cancer.

CONCLUSION

We developed a predictive model for anastomotic stricture following anterior resection of rectal cancer. This nomogram could assist clinicians in predicting the risk of anastomotic stricture, thus improving patients' quality of life and long-term 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 data extraction were performed for the included literature. We used RevMan 5.3 software to perform a meta-analysis of the pathologic complete response (pCR) rate, T stage degradation rate, resection 0 (R0) rate, anal grade 3/4 acute toxicity rate, perioperative complications, overall survival (OS), and disease-free survival (DFS) in the TNT and nCRT groups.

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.

Prediction of liver metastasis and recommended optimal follow-up nursing in rectal cancer

We aimed to analyze and investigate the clinical factors that influence the occurrence of liver metastasis in locally advanced rectal cancer patients, with an attempt to assist patients in devising the optimal imaging-based follow-up nursing. Between June 2011 and May 2021, patients with rectal cancer at our hospital were retrospectively analyzed. A random survival forest model was developed to predict the probability of liver metastasis and provide a practical risk-based approach to surveillance. The results indicated that age, perineural invasion, and tumor deposit were significant factors associated with the liver metastasis and survival. The liver metastasis risk of the low-risk group was higher at 6-21 months, with a peak occurrence time in the 15th month. The liver metastasis risk of the high-risk group was higher at 0-24 months, with a peak occurrence time in the 8th month. In general, our clinical model could predict liver metastasis in rectal cancer patients. It provides a visualization tool that can aid physicians and nurses in making clinical decisions, by detecting the probability of liver metastasis.