Acute side effects and complications after short-term preoperative radiotherapy combined with total mesorectal excision in primary rectal cancer: report of a multicenter randomized trial

Neoadjuvant Radiotherapy vs Up-Front Surgery for Resectable Locally Advanced Rectal Cancer

Importance

Guidelines for resectable locally advanced rectal cancer (LARC) advocate for neoadjuvant radiotherapy (NRT) followed by surgery as the standard approach. However, recent trials have reported no oncological benefits of NRT-based therapy for middle or lower rectal cancer, raising the question of whether NRT followed by surgery remains the optimal treatment approach for resectable LARC overall.

Objective

To compare the outcomes of NRT followed by surgery vs up-front surgery for resectable LARC.

Design, Setting, and Participants

This cohort study, using a target trial emulation framework with nationwide registries in Taiwan, included patients undergoing curative resection for resectable LARC (cT1-2N1-2, cT3Nany) between January 1, 2014, and December 31, 2017, with follow-up until December 31, 2020. Data were analyzed from January 1, 2024, to February 15, 2025.

Exposure

NRT.

Main Outcomes and Measures

The primary outcomes were overall survival (OS) and local recurrence (LR). The secondary outcome was intraoperative diverting stoma outcomes.

Results

A total of 4099 patients were analyzed, including 1436 patients undergoing NRT followed by surgery (median [IQR] age, 62.0 [53.0-71.0] years; 1036 [72.1%] male) and 2663 patients undergoing up-front surgery (median [IQR] age, 65.0 [56.0-74.0] years; 1626 [61.1%] male). NRT followed by surgery, compared with up-front surgery, was associated with higher 3-year OS rates (88.5% vs 85.2%; hazard ratio [HR], 0.74; 95% CI, 0.59-0.92) but higher permanent diverting stoma rates (20.6% vs 11.1%; relative risk [RR], 1.91; 95% CI, 1.62-2.25); LR rates were not significantly different (5.7% vs 6.6%; HR, 0.78; 95% CI, 0.55-1.11). Subgroup analysis revealed that compared with up-front surgery, NRT followed by surgery was associated with improved outcomes in middle or lower rectal cancer but not upper rectal cancer (OS: HR, 1.54; 95% CI, 0.82-2.90; LR: HR, 1.08; 95% CI, 0.23-5.00). NRT followed by surgery was associated with significantly increased risks of permanent diverting stomas across different tumor heights, particularly in upper rectal cancer (RR, 3.54; 95% CI, 1.44-8.69).

Conclusions and Relevance

In this cohort study of nationwide registries in Taiwan, NRT followed by surgery was associated with improved oncological outcomes for overall resectable LARC, with excessive diverting stoma nonreversal as the trade-off. However, the benefits of NRT were not observed for upper rectal cancer. These findings raise concerns about potential harm from NRT and advise caution when performing NRT for upper rectal cancer.

Patterns of Care and Oncologic Outcomes after Pelvic Exenteration for Locally Advanced Rectal Cancer in the United States

BACKGROUND

Pelvic exenterations (PEs) are technically demanding procedures performed with curative intent for advanced malignancies to improve patient survival while balancing morbidity and functional outcomes. The majority of United States (US) data regarding PE for rectal cancers originate from single-center series.

OBJECTIVE

We aimed to investigate patterns of care and oncologic outcomes for primary rectal cancer patients undergoing PE in a national registry.

METHODS

The National Cancer Database (2004-2019) was queried for adults with a pT4 rectal adenocarcinoma. Logistic regression identified factors associated with positive margins. Multivariable Cox regression estimated treatment effects on overall survival (OS).

RESULTS

Of 673 patients (73% <65 years of age, 39% male, 82% White), median follow-up was 39 months. The majority received neoadjuvant chemotherapy (76%) and radiation (75%), while adjuvant chemotherapy (37%) and radiation (13%) were less common. Twenty-four percent had positive margins (R1 = 98, R2 = 11, R + NOS = 48). Univariable analysis demonstrated that only nodal involvement was associated with higher positive margin rates (odds ratio 1.75, 95% confidence interval [CI] 1.22-2.51). Five-year OS for R0 and R+ resections were 55% and 33%, respectively. On multivariable analysis, age <65 years (hazard ratio [HR] 0.73, 95% CI 0.53-0.99) and adjuvant chemotherapy (HR 0.62, 95% CI 0.47-0.82) were associated with improved OS, while N+ status (HR 2.13, 95% CI 1.67-2.70) and positive margins (HR 1.82, 95% CI 1.41-2.35) portended worse prognosis. No significant associations were observed between outcomes and institutional volume.

CONCLUSION

One in four US patients undergoing PE for locally advanced rectal cancer had an R+ resection regardless of center volume. Quality of surgical resection to achieve negative margins remains the most relevant prognostic factor.

Risk Factors for Anastomotic Leakage: A Comprehensive Single-Center Analysis of Colorectal Anastomoses for Ovarian and Gastrointestinal Cancers

BACKGROUND

Anastomotic leakage (AL) is a major complication in colorectal surgery, particularly following rectal cancer surgery, necessitating effective prevention strategies. The increasing frequency of colorectal resections and anastomoses during cytoreductive surgery (CRS) for peritoneal carcinomatosis further complicates this issue owing to the diverse patient populations with varied tumor distributions and surgical complexities. This study aims to assess and compare AL incidence and associated risk factors across conventional colorectal cancer surgery (CRC), gastrointestinal CRS (GI-CRS), and ovarian CRS (OC-CRS), with a secondary focus on evaluating the role of protective ostomies.

PATIENTS AND METHODS

A retrospective analysis was performed on 1324 patients undergoing CRC, GI-CRS, and OC-CRS between January 2015 and December 2022. Multivariate analysis was utilized to identify preoperative, intraoperative, and postoperative variables as potential AL risk factors.

RESULTS

The overall AL rate was 3.0% (40/1324), with no significant differences among the three groups. Distinct risk factors were identified for each group: CRC (preoperative chemoradiotherapy), GI-CRS (ECOG score ≥ 2, preoperative albumin < 30 mg/dL), and OC-CRS (BMI < 18 kg/m2, pelvic lymphadenectomy, preoperative albumin < 30 mg/dL, anastomosis distance < 10 cm, postoperative anemia). Protective ostomies did not reduce AL incidence, and a notable discrepancy exists between AL risk factors and those influencing protective ostomy decisions.

CONCLUSIONS

AL, while rare, remains a serious postoperative complication in CRC and CRS. Key risk factors include preoperative nutritional status and surgical details such as blood supply and anastomosis level. Each patient group presents unique risks, which must be carefully weighed when considering protective ileostomy.

Short-term outcomes of transanal endoscopic intersphincteric resection for locally advanced rectal cancer after neoadjuvant chemoradiotherapy: A single-center retrospective cohort study

OBJECTIVE

To compare the perioperative safety and specimen characteristics after transanal endoscopic intersphincteric resection (taE-ISR) versus classical intersphincteric resection (cISR) in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT).

METHODS

Clinicopathological data of 145 patients (75 undergoing taE-ISR and 70 undergoing cISR after nCRT) were retrospectively analyzed. Baseline characteristics, perioperative details, and pathological specimen quality of the two groups were compared.

RESULTS

Intraoperative blood loss was lower in the taE-ISR group compared to cISR (50.0 (40.0-100.0) ml vs. 70.0 (50.0-100.0) ml, P = 0.034). Two patients (2.6 %) in the taE-ISR group and eight patients (11.4 %) in the cISR group sustained adjacent organ injury (P = 0.037). There was no statistically significant difference in the prevalence of postoperative complications between the two groups (17.3 % vs. 30.0 %, P = 0.072). However, pelvic abscess (1.3 % vs. 8.6 %, P = 0.042) and rectovaginal fistula (0.0 % vs. 5.7 %, P = 0.036) occurred less often in taE-ISR compared to cISR. The complete resection rate was higher in taE-ISR compared to cISR (98.7 % vs. 91.4 %, P = 0.042). No patients in taE-ISR had positive distal resection margins (DRM), while four patients in cISR had positive DRM (0.0 % vs. 5.7 %, P = 0.036).

CONCLUSION

taE-ISR after nCRT was associated with higher-quality specimens, reduced intraoperative blood loss, and fewer perioperative complications, attesting to the feasibility and safety of taE-ISR In low-LARC patients.

Robotic Rectal Cancer Surgery: Perioperative and Long-Term Oncological Outcomes of a Single-Center Analysis Compared with Laparoscopic and Open Approach

Background/Objectives: Robotic-assisted surgery is an attractive and promising option with unique advantages in rectal cancer surgery, but the optimal surgical approach is still debatable. Therefore, we aimed to compare the short- and long-term outcomes of the robotic-assisted approach with the laparoscopic-assisted and open approaches. Methods: A single referral center in Israel retrospectively reviewed all patients that underwent an elective rectal resection for primary non-metastatic rectal cancer between 2010 and 2020. The cohort was separated into three groups according to the surgical approach: robotic, laparoscopic, or open. Results: The cohort included 526 patients with a median age of 64 years (range 31-89), of whom 103 patients were in the robotic group, 144 in the open group, and 279 patients in the laparoscopic group. The robotic group had significantly more lower rectal tumors (24.3% versus 12.7% and 6%, respectively, p < 0.001), more locally advanced tumors (65.6% versus 51.2% and 50.2%, respectively, p = 0.004), and higher rates of neoadjuvant radiotherapy (70.9% versus 54.2% and 39.5%, respectively, p < 0.001). Conversion to an open laparotomy was more common in the laparoscopy group (23.1% versus 6.8%, respectively, p = 0.001). The open approach had higher rates of intraoperative complications (23.2% compared with 10.7% and 13.5% in the robotic and laparoscopic groups, respectively, p = 0.011), longer hospital stays (10 days compared with 7 and 8 days, respectively, p < 0.001), and higher rates of postoperative complications (76% compared with 68.9% and 59.1%, respectively, p = 0.002). The groups were similar in the number of harvested lymph nodes (14) and the incidence of positive resection margins (2.1%). The 5-year overall survival in the robotic group was 92.3% compared with 90.5% and 88.3% in the laparoscopic and open groups, respectively (p = 0.12). The 5-year disease-free survival in the robotic group was 68% compared with 71% and 63%, respectively (p = 0.2). Conclusions: The robotic, laparoscopic, and open approaches had similar histopathological outcomes and long-term oncological outcomes. The open approach was associated with higher rates of perioperative morbidity. These findings suggest that the robotic approach is safe and effective in rectal cancer surgery.

Machine learning and deep learning to improve prevention of anastomotic leak after rectal cancer surgery

Anastomotic leakage (AL) is a significant complication following rectal cancer surgery, adversely affecting both quality of life and oncological outcomes. Recent advancements in artificial intelligence (AI), particularly machine learning and deep learning, offer promising avenues for predicting and preventing AL. These technologies can analyze extensive clinical datasets to identify preoperative and perioperative risk factors such as malnutrition, body composition, and radiological features. AI-based models have demonstrated superior predictive power compared to traditional statistical methods, potentially guiding clinical decision-making and improving patient outcomes. Additionally, AI can provide surgeons with intraoperative feedback on blood supply and anatomical dissection planes, minimizing the risk of intraoperative complications and reducing the likelihood of AL development.

Advances in nanoparticle-based radiotherapy for cancer treatment

Radiotherapy has long been recognized as an effective conventional approach in both clinical and scientific research, primarily through mechanisms involving DNA destruction or the generation of reactive oxygen species to target tumors. However, significant challenges persist, including the unavoidable damage to normal tissues and the development of radiation resistance. As a result, nanotechnology-based radiotherapy has garnered considerable attention for its potential to enhance precision in irradiation, improve radiosensitization, and achieve therapeutic advancements. Importantly, radiotherapy alone frequently falls short of fully eradicating tumors. Consequently, to augment the efficacy of radiotherapy, it is often integrated with other therapeutic strategies. This review elucidates the mechanisms of radiotherapy sensitization based on diverse nanoparticles. Typically, radiotherapy is sensitized through augmenting reactive oxygen species production, targeted radiotherapy, hypoxia relief, enhancement of antitumor immune microenvironment, and G2/M cell cycle arrest. Moreover, the incorporation of nanoparticle-based anti-tumor strategies with radiotherapy markedly enhances the current state of radiotherapy. Additionally, a compilation of clinical trials utilizing nano-radioenhancers is presented. Finally, future prospects for clinical translation in this field are thoroughly examined.

Economic Evaluation of 'Watch and Wait' Following Neoadjuvant Therapy in Locally Advanced Rectal Cancer: A Systematic Review

BACKGROUND

Owing to multimodal treatment and complex surgery, locally advanced rectal cancer (LARC) exerts a large healthcare burden. Watch and wait (W&W) may be cost saving by removing the need for surgery and inpatient care. This systematic review seeks to identify the economic impact of W&W, compared with standard care, in patients achieving a complete clinical response (cCR) following neoadjuvant therapy for LARC.

METHODS

The PubMed, OVID Medline, OVID Embase, and Cochrane CENTRAL databases were systematically searched from inception to 26 April 2024. All economic evaluations (EEs) that compared W&W with standard care were included. Reporting and methodological quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS), BMJ and Philips checklists. Narrative synthesis was performed. Primary and secondary outcomes were (incremental) cost-effectiveness ratios and the net financial cost.

RESULTS

Of 1548 studies identified, 27 were assessed for full-text eligibility and 12 studies from eight countries (2016-2024) were included. Seven cost-effectiveness analyses (complete EEs) and five cost analyses (partial EEs) utilized model-based (n = 7) or trial-based (n = 5) analytics with significant variations in methodological design and reporting quality. W&W showed consistent cost effectiveness (n = 7) and cost saving (n = 12) compared with surgery from third-party payer and patient perspectives. Critical parameters identified by uncertainty analysis were rates of local and distant recurrence in W&W, salvage surgery, perioperative mortality and utilities assigned to W&W and surgery.

CONCLUSION

Despite heterogenous methodological design and reporting quality, W&W is likely to be cost effective and cost saving compared with standard care following cCR in LARC. Clinical Trials Registration PROSPERO CRD42024513874.

Tumor response rates based on initial TNM stage and tumor size in locally advanced rectal cancer: a useful tool for shared decision-making

BACKGROUND

It is accepted that tumor stage and size can influence response to neoadjuvant therapy in locally advanced rectal cancer (LARC). Studies on organ preservation to date have included a wide variety of size and TNM stage tumors. The aim of this study was to report tumor response based on each relevant TNM stage and tumor size.

METHODS

Patients treated with LARC from 2014 to 2021 with cT2-3NxM0 tumors who received neoadjuvant chemoradiotherapy with or without induction chemotherapy were included. Tumors were staged and tumor size calculated on pelvic MRI at the time of diagnosis (cTNM). Tumor size was based on the largest dimension taken on the longest axis of each tumor. Clinical response was defined on the basis of post-treatment pelvic MRI and pathological response following surgery, when performed. Statistical analysis was performed using IBM SPSS Statistics™, version 20. Data from 432 patients were analyzed as follows: cT2N0 (n = 51), cT2N+ (n = 36), cT3N0 (n = 76), cT3N+ (n = 270).

RESULTS

The rate of complete or near-complete response (cCR or nCR) varied from 77% in cT2N0 ≤ 3 cm to 20% in cT3N+ > 4 cm. Organ preservation without recurrence at 2 years was achieved in 86% of patients with cT2N0, 50% in cT2N+, 39% in cT3N0, and 12% in cT3N+.

CONCLUSION

There is significant variation in tumor response according to tumor stage and size. Tumor response appears inversely proportional to increasing TNM stage and tumor size. This data can support both refinement of selective patient recruitment to organ preservation programs and shared decision-making.

Association of Surgical Approaches and Outcomes in Total Mesorectal Excision and Margin Status for Rectal Cancer

INTRODUCTION

Despite being a key metric with a significant correlation with the outcomes of patients with rectal cancer, the optimal surgical approach for total mesorectal excision (TME) has not yet been identified. The aim of this study was to assess the association of the surgical approach on the quality of TME and surgical margins and to characterize the surgical and long-term oncologic outcomes in patients undergoing robotic, laparoscopic, and open TME for rectal cancer.

METHODS

Patients with primary, nonmetastatic rectal adenocarcinoma who underwent either lower anterior resection or abdominoperineal resection via robotic (Rob), laparoscopic (Lap), or open approaches were selected from the US Rectal Cancer Consortium database (2007-2017). Quasi-Poisson regression analysis with backward selection was used to investigate the relationship between the surgical approach and outcomes of interest.

RESULTS

Among the 664 patients included in the study, the distribution of surgical approaches was as follows: 351 (52.9%) underwent TME via the open approach, 159 (23.9%) via the robotic approach, and 154 (23.2%) via the laparoscopic approach. There were no significant differences in baseline demographics among the three cohorts. The laparoscopic cohort had fewer patients with low rectal cancer (<6 cm from the anal verge) than the robotic and open cohorts (Lap 28.6% versus Rob 59.1% versus Open 45.6%, P = 0.015). Patients who underwent Rob and Lap TME had lower intraoperative blood loss compared with the Open approach (Rob 200 mL [Q1, Q3: 100.0, 300.0] versus Lap 150 mL [Q1, Q3: 75.0, 250.0] versus Open 300 mL [Q1, Q3: 150.0, 600.0], P < 0.001). There was no difference in the operative time (Rob 243 min [Q1, Q3: 203.8, 300.2] versus Lap 241 min [Q1, Q3: 186, 336] versus Open 226 min [Q1, Q3: 178, 315.8], P = 0.309) between the three approaches. Postoperative length of stay was shorter with robotic and laparoscopic approach compared to open approach (Rob 5.0 d [Q1, Q3: 4, 8.2] versus Lap 5 d [Q1, Q3: 4, 8] versus Open 7.0 d [Q1, Q3: 5, 9], P < 0.001). There was no statistically significant difference in the quality of TME between the robotic, laparoscopic, and open approaches (79.2%, 64.9%, and 64.7%, respectively; P = 0.46). The margin positivity rate, a composite of circumferential margin and distal margin, was higher with the robotic and open approaches than with the laparoscopic approach (Rob 8.2% versus Open 6.6% versus Lap 1.9%, P = 0.17), Rob versus Lap (odds ratio 0.21; 95% confidence interval 0.05, 0.83) and Rob versus Open (odds ratio 0.5; 95% confidence interval 0.22, 1.12). There was no difference in long-term survival, including overall survival and recurrence-free survival, between patients who underwent robotic, laparoscopic, or open TME (Figure 1).

CONCLUSIONS

In patients undergoing surgery with curative intent for rectal cancer, we did not observe a difference in the quality of TME between the robotic, laparoscopic, or open approaches. Robotic and open TME compared to laparoscopic TME were associated with higher margin positivity rates in our study. This was likely due to the higher percentage of low rectal cancers in the robotic and open cohorts. We also reported no significant differences in overall survival and recurrence-free survival between the aforementioned surgical techniques.

An Institutional Shift from Routine to Selective Diversion of Low Anastomosis in Robotic TME Surgery for Rectal Cancer Patients Using the KHANS Technique: A Single-Centre Cohort Study

(1) Background: In recent years, there has been a change in practice for diverting stomas in rectal cancer surgery, shifting from routine diverting stomas to a more selective approach. Studies suggest that the benefits of temporary ileostomies do not live up to their risks, such as high-output stomas, stoma dysfunction, and reoperation. (2) Methods: All rectal cancer patients treated with a robotic resection in a single tertiary colorectal centre in the UK from 2013 to 2021 were analysed. In 2015, our unit made a shift to a more selective approach to temporary diverting ileostomies. The cohort was divided into a routine diversion group treated before 2015 and a selective diversion group treated after 2015. Both groups were analysed and compared for short-term outcomes and morbidities. (3) Results: In group A, 63/70 patients (90%) had a diverting stoma compared to 98/135 patients (72.6%) in group B (p = 0.004). There were no significant differences between the groups in anastomotic leakages (11.8% vs. 17.8%, p = 0.312) or other complications (p = 0.117). There were also no significant differences in readmission (3.8% vs. 2.6%, p = 0.312) or reoperation (3.8% vs. 2.6%, p = 1.000) after stoma closure. After 1 year, 71.6% and 71.9% (p = 1.000) of patients were stoma-free. One major reason for the delay in stoma reversal was the COVID-19 pandemic, which only occurred in group B (0% vs. 22%, p = 0.054). (4) Conclusions: A more selective approach to diverting stomas for robotic rectal cancer patients does not lead to more complications or leaks and can be considered in the treatment of rectal cancer tumours.

Comparing outcomes and cost in surgery versus watch & wait surveillance of patients with rectal cancer post neoadjuvant long course chemoradiotherapy

BACKGROUND

Watch and wait (W&W) in complete clinical responders after neoadjuvant chemoradiotherapy has increasingly robust data supporting its oncological safety. Recently, studies have assessed the real-world costs of this strategy compared to surgical resection. Our aim was to compare our oncological safety and costs associated with operative and surveillance strategies to international literature.

METHODS

Data were retrospectively collected and analysed via electronic health records from March 2014 to March 2021 in Christchurch, New Zealand. Two cohorts were created based on intention to treat. All hospital events were recorded and costed, as well as oncologic outcomes. Our primary endpoints were the cumulative cost of both strategies, 3-year survival rate, and disease-free survival.

RESULTS

Forty-eight patients were identified who had rectal cancers resected (OT) with a yPT0N0 pathology, and 42 who were on the wait-and-watch (W&W) audit after having a clinical complete response. After exclusions, we identified 38 OT and 23 W&W patients; the W&W group were more co-morbid (P = 0.05), had worse functional status (P = 0.008), higher BMI (P = 0.34) and more favourable clinical tumour staging (P = 0.01). The operative treatment (OT) group (n = 38) had more acute admissions (34% versus 13% in W&W, P = 0.08, OR 0.29). There was a 35.7% (n = 8 of 23) local recurrence in W&W and none in the OT group (P ≤ 0.001), with successful salvage in the W&W with local recurrence in 71.5% (n = 5 of 7). Three-year distant metastasis-free rate was 97.3% in the OT group and 90.9% in W&W (p = 0.05). Overall survival was 100% (W&W) and 94.7% (OT); (P = 0.019). Care in the OT group cost more than W&W, accounting for local regrowth management; $NZ70,759.56 versus $NZ47,905.52 (P = 0.014).

CONCLUSION

This study found better oncological outcomes in the OT group, whilst the W&W group had reduced morbidity and acute bed days. The cost of wait and watch was approximately two-thirds that of operative treatment, even accounting for salvage procedures for local regrowth.

Surgical Outcomes after Radiotherapy in Rectal Cancer

Over the past decade, the treatment of rectal cancer has changed considerably. The implementation of TME surgery has, in addition to decreasing the number of local recurrences, improved surgical morbidity and mortality. At the same time, the optimisation of radiotherapy in the preoperative setting has improved oncological outcomes even further, although higher perineal infection rates have been reported. Radiotherapy regimens have evolved through the adjustment of radiotherapy techniques and fields, increased waiting intervals, and, for more advanced tumours, adding chemotherapy. Concurrently, imaging techniques have significantly improved staging accuracy, facilitating more precise selection of advanced tumours. Although chemoradiotherapy does lead to the downsizing and -staging of these tumours, a very clear effect on sphincter-preserving surgery and the negative resection margin has not been proven. Aiming to decrease distant metastasis and improve overall survival for locally advanced rectal cancer, systemic chemotherapy can be added to radiotherapy, known as total neoadjuvant treatment (TNT). High complete response rates, both pathological (pCR) and clinical (cCR), are reported after TNT. Patients who follow a Watch & Wait program after a cCR can potentially avoid surgical morbidity and colostomy. For both early and more advanced tumours, trials are now investigating optimal regimens in an attempt to offer organ preservation as much as possible. Multidisciplinary deliberation should include patient preference, treatment toxicity, and likelihood of end colostomy, but also the burden of intensive surveillance in a W&W program.

Clinical risk factors and Risk assessment model for Anastomotic leakage after Rectal cancer resection

BACKGROUND

Anastomotic leakage (AL) is the most serious complication after rectal cancer surgery. Risk factors associated with AL have been documented in previous studies; however, the consensus is still lacking. In this retrospective study, we aimed to identify risk factors for AL after rectal cancer resection and to create an accurate and effective tool for predicting the risk of this complication.

METHODS

The study cohort comprised of 276 patients with rectal cancer who had undergone anterior resection between 2015 and 2020. Twenty-four selected variables were assessed by univariate and multivariate logistic regression analyses to identify independent risk factors of AL. A risk assessment model for predicting the risk of AL was established on the basis of the regression coefficients of each identified independent risk factor.

RESULTS

Anastomotic leakage occurred in 20 patients (7.2%, 20/276). Multivariate analysis identified the following variables as independent risk or protective factors of AL: perioperative ileus ( P < 0.001, odds ratio [OR] = 14.699), tumor size ≥5 cm ( P = 0.025, OR = 3.925), distance between tumor and anal verge <7.5 cm ( P = 0.045, OR = 3.512), obesity ( P = 0.032, OR = 7.256), and diverting stoma ( P = 0.008, OR = 0.143). A risk assessment model was constructed and patients were allocated to high-, medium-, and low-risk groups on the basis of risk model scores of 5-7, 2-4, and 0-1, respectively. The incidences of AL in these three groups were 61.5%, 11.9%, and 2.0%, respectively ( P < 0.001).

CONCLUSIONS

Our risk assessment model accurately and effectively identified patients at high risk of AL and could be useful in aiding decision-making aimed at minimizing adverse outcomes associated with leakage.

Patient-Relevant Costs for Organ Preservation versus Radical Resection in Locally Advanced Rectal Cancer

Total neoadjuvant therapy (TNT) is an evolving treatment schedule for locally advanced rectal cancer (LARC), allowing for organ preservation in a relevant number of patients in the case of complete response. Patients who undergo this so-called "watch and wait" approach are likely to benefit regarding their quality of life (QoL), especially if definitive ostomy could be avoided. In this work, we performed the first cost-effectiveness analysis from the patient perspective to compare costs for TNT with radical resection after neoadjuvant chemoradiation (CRT) in the German health care system. Individual costs for patients insured with a statutory health insurance were calculated with a Markov microsimulation. A subgroup analysis from the prospective "FinTox" trial was used to calibrate the model's parameters. We found that TNT was less expensive (-1540 EUR) and simultaneously resulted in a better QoL (+0.64 QALYs) during treatment and 5-year follow-up. The average cost for patients under TNT was 4711 EUR per year, which was equivalent to 3.2% of the net household income. CRT followed by resection resulted in higher overall costs for ostomy care, medication and greater loss of earnings. Overall, TNT appeared to be more efficacious and cost-effective from a patient's point of view in the German health care system.

Contemporary management of rectal cancer

The management of rectal cancer has undergone significant changes over the past 50 years, and this has been associated with major improvements in overall outcomes and quality of life. From standardization of total mesorectal excision to refinements in radiation delivery and shifting of chemoradiotherapy treatment to favor a neoadjuvant approach, as well as the development of targeted chemotherapeutics, these management strategies have continually aimed to achieve locoregional and systemic control while limiting adverse effects and enhance overall survival. This article highlights evolving aspects of rectal cancer therapy including improved staging modalities, total neoadjuvant therapy, the role of short-course and more selective radiotherapy strategies, as well as organ preservation. We also discuss the evolving role of minimally invasive surgery and comment on lateral pelvic lymph node dissection.

Key message

Rectal cancer management is constantly evolving through refinements in radiation timing and delivery, modification of chemoradiotherapy treatment schedules, and increasing utilization of minimally invasive surgical techniques and organ preservation strategies. This manuscript aims to provide a synopsis of recent changes in the management of rectal cancer, highlighting contemporary modifications in neoadjuvant approaches and surgical management to enhance the knowledge of surgeons who care for this challenging population.

Abandonment of Routine Radiotherapy for Nonlocally Advanced Rectal Cancer and Oncological Outcomes

Importance

Neoadjuvant short-course radiotherapy was routinely applied for nonlocally advanced rectal cancer (cT1-3N0-1M0 with >1 mm distance to the mesorectal fascia) in the Netherlands following the Dutch total mesorectal excision trial. This policy has shifted toward selective application after guideline revision in 2014.

Objective

To determine the association of decreased use of neoadjuvant radiotherapy with cancer-related outcomes and overall survival at a national level.

Design, Setting, and Participants

This multicenter, population-based, nationwide cross-sectional cohort study analyzed Dutch patients with rectal cancer who were treated in 2011 with a 4-year follow-up. A similar study was performed in 2021, analyzing all patients that were surgically treated in 2016. From these cohorts, all patients with cT1-3N0-1M0 rectal cancer and radiologically unthreatened mesorectal fascia were included in the current study. The data of the 2011 cohort were collected between May and October 2015, and the data of the 2016 cohort were collected between October 2020 and November 2021. The data were analyzed between May and October 2022.

Main Outcomes and Measures

The main outcomes were 4-year local recurrence and overall survival rates.

Results

Among the 2011 and 2016 cohorts, 1199 (mean [SD] age, 68 [11] years; 430 women [36%]) of 2095 patients (57.2%) and 1576 (mean [SD] age, 68 [10] years; 547 women [35%]) of 3057 patients (51.6%) had cT1-3N0-1M0 rectal cancer and were included, with proportions of neoadjuvant radiotherapy of 87% (2011) and 37% (2016). Four-year local recurrence rates were 5.8% and 5.5%, respectively (P = .99). Compared with the 2011 cohort, 4-year overall survival was significantly higher in the 2016 cohort (79.6% vs 86.4%; P < .001), with lower non-cancer-related mortality (13.8% vs 6.3%; P < .001).

Conclusions and Relevance

The results of this cross-sectional study suggest that an absolute 50% reduction in radiotherapy use for nonlocally advanced rectal cancer did not compromise cancer-related outcomes at a national level. Optimizing clinical staging and surgery following the Dutch total mesorectal excision trial has potentially enabled safe deintensification of treatment.

Small Bowel Dose Constraints in Radiation Therapy—Where Omics-Driven Biomarkers and Bioinformatics Can Take Us in the Future

Radiation-induced gastrointestinal (GI) dose constraints are still a matter of concern with the ongoing evolution of patient outcomes and treatment-related toxicity in the era of image-guided intensity-modulated radiation therapy (IMRT), stereotactic ablative radiotherapy (SABR), and novel systemic agents. Small bowel (SB) dose constraints in pelvic radiotherapy (RT) are a critical aspect of treatment planning, and prospective data to support them are scarce. Previous and current guidelines are based on retrospective data and experts’ opinions. Patient-related factors, including genetic, biological, and clinical features and systemic management, modulate toxicity. Omic and microbiome alterations between patients receiving RT to the SB may aid in the identification of patients at risk and real-time identification of acute and late toxicity. Actionable biomarkers may represent a pragmatic approach to translating findings into personalized treatment with biologically optimized dose escalation, given the mitigation of the understood risk. Biomarkers grounded in the genome, transcriptome, proteome, and microbiome should undergo analysis in trials that employ, R.T. Bioinformatic templates will be needed to help advance data collection, aggregation, and analysis, and eventually, decision making with respect to dose constraints in the modern RT era.

Transanal local excision versus intersphincteric resection for low rectal cancer with stage ypT0-1ycN0 after neoadjuvant chemoradiotherapy: an inverse probability weighting analysis for oncological and functional outcomes

OBJECTIVES

This study aimed to compare the efficacy of local excision (LE) and intersphincteric resection (ISR) in patients with locally advanced rectal cancer who achieved a significant or complete pathological response following neoadjuvant chemoradiotherapy.

METHODS

We performed a retrospective analysis of data from patients with stage ypT0-1ycN0 low rectal cancer after neoadjuvant chemoradiotherapy who underwent LE or ISR between June 2016 and June 2021. Baseline characteristics, short-term outcomes, long-term oncological outcomes, and functional outcomes, were compared between the two groups. To reduce the selection bias, inverse probability of treatment weighting (IPTW) was performed.

RESULTS

This study included 106 patients (LE group: n = 51, ISR group: n = 55). There were significant differences in baseline characteristics between the two groups (P < 0.05). After IPTW, there were almost no significant differences in baseline data between the two groups. The LE group showed less postoperative complications and better function outcomes compared to the ISR group. The LE group had significantly lower rates of complications (13.7% vs. 36.4%, P = 0.014). There were no significant differences between the two groups in terms of long-term oncological outcomes.

CONCLUSIONS

For patients with locally advanced low rectal cancer achieving significant or complete pathological response after neoadjuvant therapy, both LE and ISR present comparable oncological outcomes. Yet, LE seems to show more advantages in terms of postoperative complications and functional outcomes. These findings offer important insights for surgical decision-making, emphasizing the necessity to consider both oncological and functional outcomes in selecting the optimal surgical approach.

Radiotherapy in the preoperative neoadjuvant treatment of locally advanced rectal cancer

Radiotherapy and chemotherapy are effective treatments for patients with locally advanced rectal cancer (LARC) and can significantly improve the likelihood of R0 resection. Radiotherapy can be used as a local treatment to reduce the size of the tumor, improve the success rate of surgery and reduce the residual cancer cells after surgery. Early chemotherapy can also downgrade the tumor and eliminate micrometastases throughout the body, reducing the risk of recurrence and metastasis. The advent of neoadjuvant concurrent radiotherapy (nCRT) and total neoadjuvant treatment (TNT) has brought substantial clinical benefits to patients with LARC. Even so, given increasing demand for organ preservation and quality of life and the disease becoming increasingly younger in its incidence profile, there is a need to further explore new neoadjuvant treatment options to further improve tumor remission rates and provide other opportunities for patients to choose watch-and-wait (W&W) strategies that avoid surgery. Targeted drugs and immunologic agents (ICIs) have shown good efficacy in patients with advanced rectal cancer but have not been commonly used in neoadjuvant therapy for patients with LARC. In this paper, we review several aspects of neoadjuvant therapy, including radiation therapy and chemotherapy drugs, immune drugs and targeted drugs used in combination with neoadjuvant therapy, with the aim of providing direction and thoughtful perspectives for LARC clinical treatment and research trials.

Anastomotic leakage and functional outcomes following total mesorectal excision with delayed and immediate colo-anal anastomosis for rectal cancer: Two single-arm phase II trials

BACKGROUND

Anastomotic leakage (AL) remains a major cause of morbidity following total mesorectal excision (TME). A diverting ileostomy reduces the risk of AL but impairs quality of life (QoL). Delayed colo-anal anastomosis (DCAA) may be an alternative to immediate colo-anal anastomosis (ICAA) without creation of a diverting ileostomy.

STUDY DESIGN

Patients with T3 or N+ rectal tumours were treated with neoadjuvant chemoradiation and TME. To evaluate DCAA or ICAA with diverting ileostomy, a two multicenter single-arm phase II trials was designed. The primary endpoint was the rate of AL requiring a diverting ileostomy up to 30 days postoperatively. Secondary endpoints were 30-day postoperative complications, 1- and 2-year disease-free survival; QoL at baseline, 6 months and anorectal function measured by the low anterior resection syndrome questionnaire and Wexner score at baseline, 6 months and a late assessment at median 8 years following surgery.

RESULTS

AL requiring diverting ileostomy occurred in one patient (2.1%; 95% confidence interval (CI) [0; 11.1]) in the DCAA group and in five patients (8.6%; 95%CI [3.2; 21.0]) in the ICAA group. Thirty-day postoperative complications occurred in 13 patients (27.1%) in the DCAA group and in 10 patients (19.2%) in the ICAA group. Short and long-term functional outcomes showed similar patterns.

CONCLUSION

These two single-arm phase II trials showed that DCAA has low rates of AL requiring a diverting ileostomy and acceptable long-term functional results. DCAA seems a good choice to restore bowel continuity.

Neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy alone for patients with locally advanced rectal cancer: a propensity-score-matched analysis combined with SEER validation

BACKGROUND

Neoadjuvant therapy followed by radical surgery is recommended for locally advanced rectal cancer (LARC). But radiotherapy can cause potential adverse effects. The therapeutic outcomes, postoperative survival and relapse rates between neoadjuvant chemotherapy (N-CT) and neoadjuvant chemoradiotherapy (N-CRT) patients have rarely been studied.

METHODS

From February 2012 to April 2015, patients with LARC who underwent N-CT or N-CRT followed by radical surgery at our center were included. Pathologic response, surgical outcomes, postoperative complications and survival outcomes (including overall survival [OS], disease-free survival [DFS], cancer-specific survival [CSS] and locoregional recurrence-free survival [LRFS]) were analyzed and compared. Concurrently, the Surveillance, Epidemiology, and End Results Program (SEER) database was used to compare OS in an external source.

RESULTS

A total of 256 patients were input into the propensity score-matching (PSM) analysis, and 104 pairs remained after PSM. After PSM, the baseline data were well matched and there was a significantly lower tumor regression grade (TRG) (P < 0.001), more postoperative complications (P = 0.009) (especially anastomotic fistula, P = 0.003) and a longer median hospital stay (P = 0.049) in the N-CRT group than in the N-CT group. No significant difference was observed in OS (P = 0.737), DFS (P = 0.580), CSS (P = 0.920) or LRFS (P = 0.086) between the N-CRT group and the N-CT group. In the SEER database, patients who received N-CT had similar OS in both TNM II (P = 0.315) and TNM III stages (P = 0.090) as those who received N-CRT.

CONCLUSION

N-CT conferred similar survival benefits but caused fewer complications than N-CRT. Thus, it could be an alternative treatment of LARC.

Impact of Total Neoadjuvant Therapy on Postoperative Outcomes After Proctectomy for Rectal Cancer

BACKGROUND

Total neoadjuvant therapy is an alternative to neoadjuvant chemoradiation alone for rectal cancer and has the benefits of more completion of planned therapy, increased downstaging, earlier treatment of micrometastases, and assessment of chemosensitivity; however, it may increase surgical complications, especially with increased radiation-to-surgery interval.

OBJECTIVE

The study aimed to determine the impact of total neoadjuvant therapy on postoperative complications compared with neoadjuvant chemoradiation alone.

DESIGN

Retrospective cohort study.

SETTINGS

Single tertiary referral center.

PATIENTS

The patient included was a stage II/III rectal cancer patient who underwent total neoadjuvant therapy or long-course neoadjuvant chemoradiation followed by surgical resection from 2018-2020.

MAIN OUTCOME MEASURES

The main outcome measures included severe postoperative complications (Clavien-Dindo grade ≥3).

RESULTS

Of 181 patients, 86 (47.5%) underwent total neoadjuvant therapy and 95 (52.5%) underwent neoadjuvant chemoradiation. There was no difference in severe postoperative complications or any complications. There was also no difference in the rate of complete total mesorectal excision or negative circumferential margin. Total neoadjuvant therapy had a mean operative time of 355.5 minutes and estimated blood loss of 263.6 mL compared with 326.7 minutes and 297.5 mL in the neoadjuvant chemoradiation group. Total neoadjuvant therapy patients had a lower mean lymph node yield than neoadjuvant chemoradiation patients. On multivariable analysis, total neoadjuvant therapy was associated with increased operative time (OR, 1.19; p < 0.001) and estimated blood loss (OR, 1.22; p < 0.001) and decreased lymph node yield (OR, 0.67; p < 0.001). There was no difference in severe complications or any complications.

LIMITATIONS

Selection bias uncontrolled by modeling.

CONCLUSIONS

We found no difference in risk of postoperative complications between patients who received total neoadjuvant therapy vs neoadjuvant chemoradiation. Total neoadjuvant therapy patients had longer operations and greater estimated blood loss. This may be a reflection of increased operative difficulty because of increased radiation-to-surgery interval and/or the effects of chemotherapy; however, the absolute differences were small and, therefore, should be interpreted cautiously. See Video Abstract at http://links.lww.com/DCR/C44 .

IMPACTO DE LA TERAPIA NEOADYUVANTE TOTAL EN LOS RESULTADOS POSOPERATORIOS DESPUS DE UNA PROCTECTOMA POR CNCER DE RECTO

ANTECEDENTES:La terapia neoadyuvante total es una alternativa a la quimiorradiación neoadyuvante sola para el cáncer de recto y tiene los beneficios de una mayor finalización de la terapia planificada, mayor reducción del estadiage, tratamiento más temprano de las micrometástasis y evaluación de la quimiosensibilidad; sin embargo, puede aumentar las complicaciones quirúrgicas, especialmente con un mayor intervalo entre la radiación y la cirugía.OBJETIVO:Determinar el impacto de la terapia neoadyuvante total sobre las complicaciones posoperatorias en comparación con la quimiorradiación neoadyuvante sola.DISEÑO:Estudio de cohorte retrospectivo.ENTORNO CLINICO:Centro único de referencia terciario.PACIENTES:Paciente con cáncer de recto en estadio II/III que se sometieron a terapia neoadyuvante total o quimiorradiación neoadyuvante de larga duración seguida de resección quirúrgica entre 2018 y 2020.PRINCIPALES MEDIDAS DE RESULTADO:Complicaciones postoperatorias graves (grado de Clavien-Dindo ≥3).RESULTADOS:De 181 pacientes, 86 (47,5%) se sometieron a terapia neoadyuvante total y 95 (52,5%) se sometieron a quimiorradioterapia neoadyuvante. No hubo diferencia en las complicaciones postoperatorias graves o cualquier otra complicación. Tampoco hubo diferencia en la tasa de escisión mesorrectal total completa o margen circunferencial negativo. La terapia neoadyuvante total tuvo un tiempo operatorio promedio de 355,5 minutos y una pérdida de sangre estimada de 263,6 ml en comparación con 326,7 minutos y 297,5 ml en el grupo de quimiorradiación neoadyuvante. Los pacientes con terapia neoadyuvante total tuvieron una media de ganglios linfáticos más bajo en comparación con los pacientes con quimiorradioterapia neoadyuvante. En el análisis multivariable, la terapia neoadyuvante total se asoció con un mayor tiempo operatorio (OR = 1,19, p < 0,001) y pérdida de sangre estimada (OR = 1,22, p < 0,001) y menor cantidad los ganglios linfáticos (OR = 0,67, p < 0,001). No hubo diferencia en las complicaciones graves o cualquier complicación.LIMITACIONES:Sesgo de selección no controlado por modelado.CONCLUSIONES:No encontramos diferencias en el riesgo de complicaciones postoperatorias entre los pacientes que recibieron terapia neoadyuvante total versus quimiorradiación neoadyuvante. Los pacientes con terapia neoadyuvante total tuvieron operaciones más prolongadas y una mayor pérdida de sangre estimada. Esto puede ser un reflejo de una mayor dificultad quirúrgica como resultado de un mayor intervalo entre la radiación y la cirugía y/o los efectos de la quimioterapia; sin embargo, las diferencias absolutas fueron pequeñas y, por lo tanto, deben interpretarse con cautela. Consulte Video Resumen en http://links.lww.com/DCR/C44 . (Traducción- Dr. Francisco M. Abarca-Rendon ).

Efficacy of hypofractionated preoperative chemoradiotherapy in rectal cancer

The efficacy and toxicity of hypofractionated preoperative chemoradiotherapy (HPCRT) combined with oral capecitabine was evaluated in patients with rectal cancer. HPCRT was delivered by intensity-modulated radiotherapy of either 33 Gy to the whole pelvis or 35 Gy in 10 fractions to the primary tumor and 33 Gy to the surrounding pelvis. Surgery was performed 4-8 weeks after HPCRT completion. Oral capecitabine was administered concurrently. A total of 76 patients were eligible for this study, and patient numbers in clinical stages I, II, III and IVA were 5, 29, 36 and 6, respectively. Tumor response, toxicity and survival were analyzed. A total of 9/76 patients (11.8%) achieved a pathological complete response. Sphincter preservation was achieved in 23/32 (71.9%) and 44/44 (100%) of patients with a distal extent from the anal verge of ≤5 and >5 cm, respectively. A total of 28/76 patients (36.8%) achieved tumor-downstaging and 25/76 (32.9%) achieved nodal (N)-downstaging. The 5-year disease-free survival (DFS) and overall survival rates were 76.5% and 90.6%, respectively. In the multivariate analysis for DFS, pathological N stage and lymphovascular space invasion were notable prognostic factors. A total of 6 patients in stage IVA underwent salvage treatments for lung or liver metastasis after HPCRT completion, and all 6 were alive at the last follow-up. Only 4 patients experienced grade 3 postoperative complications. No grade 4 toxicities were observed. HPCRT of 33 or 35 Gy in 10 fractions showed similar results to those of long-course fractionation. This fractionation scheme could be beneficial for patients with early stage disease, locally advanced rectal cancer, simultaneous distant metastasis requiring early intervention or for patients who wish to avoid multiple hospital visits.

New Opportunities for Minimizing Toxicity in Rectal Cancer Management

Advances in multimodal management of locally advanced rectal cancer (LARC), consisting of preoperative chemotherapy and/or radiotherapy followed by surgery with or without adjuvant chemotherapy, have improved local disease control and patient survival but are associated with significant risk for acute and long-term morbidity. Recently published trials, evaluating treatment dose intensification via the addition of preoperative induction or consolidation chemotherapy (total neoadjuvant therapy [TNT]), have demonstrated improved tumor response rates while maintaining acceptable toxicity. In addition, TNT has led to an increased number of patients achieving a clinical complete response and thus eligible to pursue a nonoperative, organ-preserving, watch and wait approach, thereby avoiding toxicities associated with surgery, such as bowel dysfunction and stoma-related complications. Ongoing trials using immune checkpoint inhibitors in patients with mismatch repair-deficient tumors suggest that this subgroup of patients with LARC could potentially be treated with immunotherapy alone, sparing them the toxicity associated with preoperative treatment and surgery. However, the majority of rectal cancers are mismatch repair-proficient and less responsive to immune checkpoint inhibitors and require multimodal management. The synergy noted in preclinical studies between immunotherapy and radiotherapy on immunogenic tumor cell death has led to the design of ongoing clinical trials that explore the benefit of combining radiotherapy, chemotherapy, and immunotherapy (mainly of immune checkpoint inhibitors) and aim to increase the number of patients eligible for organ preservation.

Predictive Factors for Anastomotic Leakage Following Colorectal Cancer Surgery: Where Are We and Where Are We Going?

Anastomotic leakage (AL) remains one of the most severe complications following colorectal cancer (CRC) surgery. Indeed, leaks that may occur after any type of intestinal anastomosis are commonly associated with a higher reoperation rate and an increased risk of postoperative morbidity and mortality. At first, our review aims to identify specific preoperative, intraoperative and perioperative factors that eventually lead to the development of anastomotic dehiscence based on the current literature. We will also investigate the role of several biomarkers in predicting the presence of ALs following colorectal surgery. Despite significant improvements in perioperative care, advances in surgical techniques, and a high index of suspicion of this complication, the incidence of AL remained stable during the last decades. Thus, gaining a better knowledge of the risk factors that influence the AL rates may help identify high-risk surgical patients requiring more intensive perioperative surveillance. Furthermore, prompt diagnosis of this severe complication may help improve patient survival. To date, several studies have identified predictive biomarkers of ALs, which are most commonly associated with the inflammatory response to colorectal surgery. Interestingly, early diagnosis and evaluation of the severity of this complication may offer a significant opportunity to guide clinical judgement and decision-making.

Essential updates 2020/2021: Advancing precision medicine for comprehensive rectal cancer treatment

In the paradigm shift related to rectal cancer treatment, we have to understand a variety of new emerging topics to provide appropriate treatment for individual patients as precision medicine. However, information on surgery, genomic medicine, and pharmacotherapy is highly specialized and subdivided, creating a barrier to achieving thorough knowledge. In this review, we summarize the perspective for rectal cancer treatment and management from the current standard-of-care to the latest findings to help optimize treatment strategy.

Development of a Patient Decision Aid for Rectal Cancer Patients with Clinical Complete Response after Neo-Adjuvant Treatment

Surgery is the primary component of curative treatment for patients with rectal cancer. However, patients with a clinical complete response (cCR) after neo-adjuvant treatment may avoid the morbidity and mortality of radical surgery. An organ-sparing strategy could be an oncological equivalent alternative. Therefore, shared decision making between the patient and the healthcare professional (HCP) should take place. This can be facilitated by a patient decision aid (PtDA). In this study, we developed a PtDA based on a literature review and the key elements of the Ottawa Decision Support Framework. Additionally, a qualitative study was performed to review and evaluate the PtDA by both HCPs and former rectal cancer patients by a Delphi procedure and semi-structured interviews, respectively. A strong consensus was reached after the first round (I-CVI 0.85-1). Eleven patients were interviewed and most of them indicated that using a PtDA in clinical practice would be of added value in the decision making. Patients indicated that their decisional needs are centered on the impact of side effects on their quality of life and the outcome of the different options. The PtDA was modified taking into account the remarks of patients and HCPs and a second Delphi round was held. The second round again showed a strong consensus (I-CVI 0.87-1).

Preclinical Evaluation of a Novel Small Molecule LCC-21 to Suppress Colorectal Cancer Malignancy by Inhibiting Angiogenic and Metastatic Signatures

Colorectal cancer (CRC) is one of the most common cancers, and it frequently metastasizes to the liver and lymph nodes. Despite major advances in treatment modalities, CRC remains a poorly characterized biological malignancy, with high reported cases of deaths globally. Moreover, cancer stem cells (CSCs) and their microenvironment have been widely shown to promote colon cancer development, progression, and metastasis. Therefore, an understanding of the underlying mechanisms that contribute to the maintenance of CSCs and their markers in CRC is crucial in efforts to treat cancer metastasis and develop specific therapeutic targets for augmenting current standard treatments. Herein, we applied computational simulations using bioinformatics to identify potential theranostic markers for CRC. We identified the overexpression of vascular endothelial growth factor-α (VEGFA)/β-catenin/matrix metalloproteinase (MMP)-7/Cluster of Differentiation 44 (CD44) in CRC to be associated with cancer progression, stemness, resistance to therapy, metastasis, and poor clinical outcomes. To further investigate, we explored in silico molecular docking, which revealed potential inhibitory activities of LCC-21 as a potential multitarget small molecule for VEGF-A/CTNNB1/MMP7/CD44 oncogenic signatures, with the highest binding affinities displayed. We validated these finding in vitro and demonstrated that LCC-21 inhibited colony and sphere formation, migration, and invasion, and these results were further confirmed by a Western blot analysis in HCT116 and DLD-1 cells. Thus, the inhibitory effects of LCC-21 on these angiogenic and onco-immunogenic signatures could be of translational relevance as potential CRC biomarkers for early diagnosis.

A Phase I Trial of Neoadjuvant Stereotactic Body Radiotherapy Prior to Radical Prostatectomy for Locally Advanced Prostate Cancer

PURPOSE

Men with locally advanced prostate cancer who undergo radical prostatectomy (RP) often develop recurrence and require postoperative radiotherapy. We aimed to determine the safety of neoadjuvant stereotactic body radiotherapy (SBRT) before RP in this population.

METHODS AND PATIENTS

A single-institution phase 1 trial (NCT02946008) of men with high-risk or node-positive prostate cancer were enrolled between March and October 2017. The primary endpoint was to determine the maximum tolerated dose of SBRT based on a composite 30-day post-RP toxicity goal of ≤28% of patients experiencing a dose-limiting toxicity (DLT). Secondary outcomes included toxicity, efficacy, and multiple quality of life (QoL) inventories. SBRT (30-35 Gy/5 fractions) was delivered to the prostate and seminal vesicles, and 25 Gy/5 fractions to the pelvic lymph nodes. RP was performed for a median of 6 weeks post-SBRT. Hormone therapy was not allowed.

RESULTS

Median follow-up was 40 months (range, 33-44). Twenty-five percent of the patients (n = 4) experienced a DLT within 30 days post-RP; however, the trial was stopped early (n = 16 of planned 38 patients) owing to the proportion and severity of the late adverse events. Post-RP grade 3 genitourinary and gastrointestinal toxicities occurred in 75% (n = 12) and 25% (n = 4) of patients, respectively. Two patients required cystectomy and urinary diversion ≥2 years post-RP. At 24 months post-RP, 75% (n = 12) of men used ≥1 pad/d and 0% had erections suitable for intercourse. Surgical margins were negative in all patients and 31% (n = 5) had complete or partial (pre-RP) MRI-response to SBRT. Three-year biochemical recurrence and distant metastasis were 45% (95% CI, 5%-68%) and 28% (95% CI, 0%-49%), respectively.

CONCLUSIONS

Neoadjuvant SBRT followed by RP resulted in unacceptably high toxicity and severe QoL declines.

Anastomotic Leak in Colorectal Surgery: Predictive Factors and Survival

<br><b>Introduction:</b> Anastomotic leak (AL) is a serious complication following colorectal surgery.</br> <br><b>Aim:</b> The aim of this study was to identify factors associated with the development of AL and to analyze its impact on survival.</br> <br><b>Materials and methods:</b> All consecutive adult colorectal cancer resections performed between 2007 and 2020 with curative intent and anastomosis formation were included from a prospectively maintained database. The primary outcome measure was the rate of AL. The secondary outcome measure was 5-year overall survival (OS).</br> <br><b>Results:</b> There were 6837 eligible patients. The rate of AL was 2.2% and 4.0% in patients with colon and rectal cancer, respectively. AL was a significant independent predictor of reduced 5-year OS in patients who underwent curative surgery for rectal cancer (odds ratio 2.293, p = 0.009). Emergency surgery (p = 0.015), surgery at a public hospital (p = 0.002), and an open surgical approach (p = 0.021) were all associated with a significantly higher risk of AL in patients with colon cancer, with higher rates of AL noted in left colectomies as compared to right hemicolectomies (4.4% <i>vs.</i> 1.3%, p < 0.001). In rectal cancer patients, AL was associated with neoadjuvant chemoradiotherapy (p = 0.038) and male gender (p = 0.002). The anastomosis formation technique (hand-sewn <i>vs.</i> stapled) did not impact the rate of AL (p = 0.116 and p = 0.198 with colon and rectal cancer, respectively).</br> <br><b>Discussion:</b> Clinicians should be cognizant of the predictive factors for AL and should consider early intervention for at-risk patients.</br>.

Preoperative short-course radiation therapy with PROtons compared to photons in high-risk RECTal cancer (PRORECT): Initial dosimetric experience

Background and purpose

Neoadjuvant short-course radiotherapy (SCRT) followed by full-dose systemic chemotherapy is an established treatment modality in locally advanced rectal cancer (LARC). Until recently, SCRT has been exclusively delivered with photons. Proton beam therapy (PBT) may minimize acute toxicity, which in turn likely impacts favorably on the tolerability to subsequent chemotherapy. The aim of this study is a dosimetric comparison between SCRT with photons and protons in the randomized phase II trial PRORECT (NCT04525989).

Materials and methods

From June 2021 to June 2022, twenty consecutive patients with LARC have been treated according to study protocol. For each patient, both a VMAT and a PBT treatment plans have been generated and compared pairwise.

Results

Dose-volume histogram (DVH) analysis revealed that SCRT with protons significantly reduced radiation dose to pelvic organs at risk including bladder, bones, and bowel in comparison to SCRT with photons. Photon and proton treatment plans had equivalent conformity and homogeneity indexes.

Conclusion

Preoperative SCRT with protons offers a significant reduction of radiation dose to normal tissues compared with current photon-based radiotherapy technique. Demonstrated dosimetric advantages may translate into measurable clinical benefits in patients with LARC. Clinical implications of the dosimetric superiority of SCRT with protons will be presented in the coming reports from the PRORECT trial.

Transanal Endoscopic Microsurgery Versus Total Mesorectal Excision in ypT0-1 Rectal Cancer After Preoperative Radiochemotherapy: Postoperative Morbidity, Functional Results, and Long-term Oncologic Outcome

BACKGROUND

In patients with locally advanced extraperitoneal rectal cancer, a multidisciplinary approach represents the standard treatment. However, considering the favorable prognosis in patients with major or complete response, radical surgery might represent overtreatment.

OBJECTIVE

This study aimed to evaluate postoperative short-term morbidity, functional outcome, and oncologic long-term outcome in patients with rectal cancer treated with local excision by transanal endoscopic microsurgery or radical surgery and to determine who achieved a complete or major pathological response (ypT0-1) after neoadjuvant treatment.

DESIGN

This was a retrospective study.

SETTING

The study was conducted at a single center.

PATIENTS

Patients who had received neoadjuvant treatment by local excision with a major or complete pathological response at histological examination (transanal endoscopic microsurgery group) were compared to patients treated by radical surgery with the same pathological response (total mesorectal excision group).

INTERVENTIONS

The interventions included local excision by transanal endoscopic microsurgery and radical surgery with total mesorectal excision.

MAIN OUTCOME MEASURES

Postoperative short-term morbidity, functional outcome 1 year after surgery, and oncologic long-term outcome were measured.

RESULTS

Ninety-three patients were included in the study (35 in the transanal endoscopic microsurgery group and 58 in the mesorectal excision group). In the total mesorectal excision group, a sphincter-saving approach was possible in 89.7% (vs 100%; p = 0.049); a protective temporary stoma was necessary in 74.1% of radical procedures (vs 0%; p < 0.001), and 13.8% of these became permanent. Short-term postoperative morbidity was lower after local excision (14.3% vs 46.6%; p = 0.002). One year after surgery, the transanal endoscopic microsurgery group recorded better evacuation and continence function than the total mesorectal excision group. Oncologic outcome was similar between the groups.

LIMITATIONS

This study had a retrospective design.

CONCLUSION

If a major or complete pathological response occurs after neoadjuvant treatment, an organ-sparing approach by local excision seems to offer the same oncologic results as radical surgery, but it has a better postoperative morbidity rate and better functional results. See Video Abstract at http://links.lww.com/DCR/B901 .Microcirugía endoscópica transanal versus escisión total del mesorrecto en cáncer de recto ypT0-1 después de radioquimioterapia preoperatoria: morbilidad posoperatoria, resultados funcionales y resultado oncológico a largo plazo.

ANTECEDENTES

En pacientes con cáncer rectal extraperitoneal localmente avanzado, un abordaje multidisciplinario con radioquimioterapia preoperatoria y cirugía con escisión total del mesorrecto representa el tratamiento estándar. En pacientes que obtienen una respuesta mayor o completa, la cirugía radical puede representar un sobretratamiento, considerando el pronóstico favorable de estos casos.

OBJETIVO

Evaluar la morbilidad posoperatoria a corto plazo, el resultado funcional y el resultado oncológico a largo plazo en pacientes con cáncer de recto tratados con escisión local mediante microcirugía endoscópica transanal o mediante cirugía radical y que obtuvieron una respuesta patológica completa o mayor (ypT0-1) después del tratamiento neoadyuvante.

DISEO

Este fue un estudio retrospectivo.

AJUSTE

El estudio se realizó en un solo centro.

ESCENARIO

El estudio se realizó en un solo centro.

PACIENTES

Se comparó a los pacientes tratados, tras tratamiento neoadyuvante (1996-2016), mediante escisión local con respuesta patológica mayor o completa al examen histológico (grupo de microcirugía endoscópica transanal), con los pacientes tratados mediante cirugía radical con la misma respuesta patológica (grupo de escisión mesorrectal total).

INTERVENCIONES

Extirpación local mediante microcirugía endoscópica transanal y cirugía radical con escisión mesorrectal total.

PRINCIPALES MEDIDAS DE RESULTADO

Morbilidad posoperatoria a corto plazo, resultado funcional a un año después de la cirugía (evaluado con una puntuación de evacuación y continencia) y resultado oncológico a largo plazo.

LIMITACIONES

Las limitaciones de este estudio incluyen su diseño retrospectivo.

CONCLUSIN

Si se produce una respuesta patológica mayor o completa después del tratamiento neoadyuvante, un abordaje con preservación de órganos mediante escisión local parece ofrecer los mismos resultados oncológicos que la cirugía radical, pero tiene una menor tasa de morbilidad postoperatoria y mejores resultados funcionales un año después de la cirugía. Consulte Video Resumen en http://links.lww.com/DCR/B901 . (Traducción-Dr. Felipe Bellolio ).

Decreasing the Adverse Effects in Pelvic Radiation Therapy: A Randomized Controlled Trial Evaluating the Use of Probiotics

PURPOSE

The aim of this randomized controlled trial was to evaluate the potential benefit from 2 probiotic bacteria of the species Lactiplantibacillus plantarum against radiation therapy-induced comorbidities.

METHODS AND MATERIALS

Women (>18 years of age) scheduled for radiation therapy because of gynecologic cancer were randomly allocated to consume placebo or either low-dose probiotics (1 × 10¹⁰ colony-forming unit/capsule twice daily) or high-dose probiotics (5 × 10¹⁰ colony-forming unit/capsule twice daily). The intervention started approximately 1 week before the onset of radiation therapy and continued until 2 weeks after completion. During this period the participants were daily filling in a study diary documenting the incidence and severity of symptoms, intake of concomitant medication, and stool consistency. The primary endpoint was the probiotic effect on the mean number of loose stools during radiation therapy.

RESULTS

Of the 97 randomized women, 75 provided data for the analysis of the results. The mean number of loose stools (sum of Bristol stool type 6 and 7) was not significantly reduced in the probiotic groups, but there was a significant reduction in the mean number of days with >1 loose stool with 15.04 ± 8.92 days in the placebo and 8.65 ± 5.93 days in the high-dose probiotics group (P = .014). The benefit was even more pronounced in the 2 weeks following the end of radiation therapy (P = .005). Moreover, intake of the probiotics resulted in a reduced severity of the symptoms grinding abdominal pain (P = .041) and defecation urgency (P = .08) and a reduced percentage of days with these symptoms (P = .023 and P = .042, respectively), compared with placebo. There were no differences regarding reported adverse events.

CONCLUSIONS

Intake of the 2 probiotic bacteria was beneficial and reduced many measures or symptoms of the radiation-induced toxicity in women treated for gynecologic cancer.

Risk and prognosis of second corpus uteri cancer after radiation therapy for pelvic cancer: A population-based analysis

BACKGROUND

Radiation therapy (RT) is a standard treatment for the local control of primary pelvic cancers (PPC), yet the risk of second corpus uteri cancer (SCUC) in PPC patients undergoing RT is still controversial. This study investigated the impact of RT on the risk of SCUC and assessed the survival outcome.

METHODS

We queried nine cancer registries for PPC cases in the Surveillance, Epidemiology, and End Results (SEER) database. The cumulative incidence of SCUC was analyzed using Cox regression and Fine-Gray competing risk regression analysis. The Poisson regression analysis was employed to assess the standardized incidence ratios (SIRs) and radiation-attributed risk (RR) for SCUC. We evaluated the overall survival of patients with SCUC using the Kaplan-Meier method.

RESULTS

Receiving radiotherapy was strongly associated with a higher risk of developing SCUC for PPC patients in Fine-Gray competing risk regression (No-RT vs. RT: adjusted HR = 1.77; 95% CI, 1.40-2.28; p < 0.001). The incidence of SCUC in PPC patients who received RT was higher than in the US general population (SIR, 1.66; 95% CI, 1.41-1.93; p < 0.05), but the incidence of SCUC in patients who did not receive RT was lower than with the US general population (SIR, 0.68; 95% CI, 0.61-0.75; p < 0.05). The dynamic SIR and RR for SCUC decreased with decreasing age at PPC diagnosis and decreased with time progress. In terms of overall survival, 10-year survival rates with SCUC after No-RT (NRT) and SCUC after RT were 45.9% and 25.9% (HR = 1.82; 95% CI, 1.46-2.29; p < 0.001), respectively.

CONCLUSION

Radiotherapy for primary pelvic cancers is associated with a higher risk of developing SCUC than patients unexposed to radiotherapy. We suggest that patients with pelvic RT, especially young patients, should receive long-term monitoring for the risk of developing SCUC.

The impact of anastomotic leak on long-term oncological outcomes after low anterior resection for mid-low rectal cancer: extended follow-up of a randomised controlled trial

PURPOSE

The impact of anastomotic leaks (AL) on oncological outcomes after low anterior resection for mid-low rectal cancer is still debated. The aim of this study was to evaluate overall survival (OS), disease-free survival (DFS), and local and distant recurrence in patients with AL following low anterior resection.

METHODS

This is an extension of a multicentre RCT (NCT01110798). Kaplan-Meier method and the log-rank test were used to estimate and compare the 3-, 5-, and 10-year OS and DFS, and local and distant recurrence in patients with and without AL. Predictors of OS and DFS were evaluated using the Cox regression analysis as secondary aim.

RESULTS

Follow-up was available for 311 patients. Of them, 252 (81.0%) underwent neoadjuvant chemoradiotherapy and 138 (44.3%) adjuvant therapy. AL occurred in 63 (20.3%) patients. At a mean follow-up of 69.5 ± 31.9 months, 23 (7.4%) patients experienced local recurrence and 49 (15.8%) distant recurrence. The 3-, 5-, and 10-year OS and DFS were 89.2%, 85.3%, and 70.2%; and 80.7%, 75.1%, and 63.5% in patients with AL, and 88.9%, 79.8% and 72.3%; and 83.7, 74.2 and 62.8%, respectively in patients without (p = 0.89 and p = 0.84, respectively). At multivariable analysis, AL was not an independent predictor of OS (HR 0.65, 95%CI 0.34-1.28) and DFS (HR 0.70, 95%CI 0.39-1.25), whereas positive circumferential resection margins and pathological stage impaired both.

CONCLUSIONS

In the context of modern multimodal rectal cancer treatment, AL does not affect long-term OS, DFS, and local and distant recurrence in patients with mid-low rectal cancer.

Nonoperative versus Operative Approach According to the Response to Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Prospective Cohort Study

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Watch-and-wait patients after chemoradiotherapy for rectal cancer have good functional outcome.

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No survival differences were seen between patients undergoing surgery versus patients in a watch-and-wait protocol.

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There is a subset of patients that has initial favorable response but will recur with distant metastases afterwards.

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A previously published model predicting (near)-complete response could not be validated.

Purpose

To report on organ preservation following chemoradiotherapy (CRT) in a prospective cohort of locally advanced rectal cancer patients.

Methods and materials

Fifty-two patients received CRT. MRI and ¹⁸F-FDG-PET/CT were performed prior to CRT. Response assessment was done 6 and 12 weeks after CRT using digital rectal examination, MRI, ¹⁸F-FDG-PET/CT and endoscopy. For clinical complete response or minimal residual disease, a watch-and-wait (W&W) protocol was started.

Regrowth-free survival (ReFS), Total Mesorectal Excision-free disease-free survival, distant metastasis-free survival (DMFS) and overall survival (OS) were evaluated using Kaplan-Meier method. Functional outcome was compared with the Wilcoxon signed-rank test using EORTC QLQ-C30, MSKCC BFI, LARS and IIEF-5/FSFI-5 questionnaires. A previously developed prediction model performance was tested using receiver operating characteristic analysis.

Results

29/52 patients entered a W&W protocol. There was no difference in two-year DMFS (81.1 % vs 78.8 %, p = 0.82), two-year OS (96.4 % vs 100 %, p = 0.38) and two-year DFS (77.5 % vs 78.8 %, p = 0.87) between W&W patients and those who underwent surgery at 12 weeks after CRT. Two-year DMFS differed between W&W with local regrowth, W&W with sustained response and patients who had surgery (66.7 % vs 88.0 % vs 78.8 %; p = 0.04). At 6 and 12 months, W&W patients reported good QoL and bowel function. The model validation reached an AUC of 0.627.

Conclusion

Good functional outcome in patients with rectal cancer allocated to surveillance after CRT needs to be balanced against potentially worse DMFS in a subset of patients without sustained clinical complete response. Reliable prediction of patients eligible for surveillance programs needs further investigation.

Short-term outcomes of robotic-assisted surgery following neoadjuvant chemotherapy for lower rectal cancer

INTRODUCTION

There have been reports about robotic surgery for rectal cancer with chemoradiotherapy (CRT), but only a few studies have compared the use of robotic surgery with and without neoadjuvant chemotherapy (NAC). The aim of our study was to compare the perioperative outcomes of robotic surgery with and without NAC for lower rectal cancer and to examine the effects of NAC on robotic surgery.

METHODS

From January 2016 to July 2021, we compared the short-term outcomes of 45 patients who did not undergo NAC and 55 patients who underwent NAC.

RESULTS

The rate of sphincter-preserving surgeries was higher in the NAC group than in the non-NAC group (P = .024). The total operative time was significantly longer in the NAC group than in the non-NAC group (P < .001). The rate of lateral lymph node dissection was significantly higher in the NAC group than in the non-NAC group (P < .001). No significant differences were identified in the rate of incisional surgical site infections (SSI), organ/space SSI postoperative bleeding, small bowel obstruction, anastomotic leakage, urinary dysfunction, or urinary infections between the groups. There were eight incidences of lateral lymph node metastasis (15%) and two cases with positive resection margins (4.0%) in the NAC group.

CONCLUSIONS

Robotic surgery after NAC has few complications and a higher sphincter-preserving rate that without NAC.

The Long and the Short of it: the Role of Short-course Radiotherapy in the Neoadjuvant Management of Rectal Cancer

Total mesorectal excision is the cornerstone of treatment for rectal cancer. Multiple randomised trials have shown a reduction in local recurrence rates with the addition of preoperative radiotherapy, either as a 1-week hypofractionated short-course (SCRT) or a conventionally fractionated long-course (LCRT) schedule with concurrent chemotherapy. There is also increasing interest in the addition of neoadjuvant chemotherapy to radiotherapy with the aim of improving disease-free survival. The relative use of SCRT and LCRT varies considerably across the world. This is reflected in, and is probably driven in part by, disparity between international guideline recommendations. In addition, different approaches to treatment may exist both between and within countries, with variation related to patient, disease and treatment centre and financial factors. In this review, we will specifically focus on the use of SCRT for the treatment of rectal cancer. We will discuss the literature base and current guidelines, highlighting the challenges and controversies in clinical application of this evidence. We will also discuss potential future applications of SCRT, including its role in optimisation and intensification of treatment for rectal cancer.

UK 2022 Consensus on Normal Tissue Dose-Volume Constraints for Oligometastatic, Primary Lung and Hepatocellular Carcinoma Stereotactic Ablative Radiotherapy

The use of stereotactic ablative radiotherapy (SABR) in the UK has expanded over the past decade, in part as the result of several UK clinical trials and a recent NHS England Commissioning through Evaluation programme. A UK SABR Consortium consensus for normal tissue constraints for SABR was published in 2017, based on the existing literature at the time. The published literature regarding SABR has increased in volume over the past 5 years and multiple UK centres are currently working to develop new SABR services. A review and update of the previous consensus is therefore appropriate and timely. It is hoped that this document will provide a useful resource to facilitate safe and consistent SABR practice.

Targeted Phototherapy by Niobium Carbide for Mammalian Tumor Models Similar to Humans

BACKGROUND

In the past few decades, nanomaterial-mediated phototherapy has gained significant attention as an alternative antitumor strategy. However, its antitumor success is majorly limited to the treatment of subcutaneous tumors in nude mice. In fact, no studies have been previously conducted in this area/field on clinically-relevant big animal models. Therefore, there is an urgent need to conduct further investigation in a typical big animal model, which is more closely related to the human body.

RESULTS

In this study, niobium carbide (NbC) was selected as a photoactive substance owing to the presence of outstanding near-infrared (NIR) absorption properties, which are responsible for the generation of NIR-triggered hyperthermia and reactive oxygen species that contribute towards synergetic photothermal and photodynamic effect. Moreover, the present study utilized macrophages as bio-carrier for the targeted delivery of NbC, wherein phagocytosis by macrophages retained the photothermal/photodynamic effect of NbC. Consequently, macrophage-loaded NbC ensured/allowed complete removal of solid tumors both in nude mice and big animal models involving rabbits. Meanwhile, two-dimensional ultrasound, shave wave elastography (SWE), and contrast-enhanced ultrasound (CEUS) were used to monitor physiological evolution in tumor in vivo post-treatment, which clearly revealed the occurrence of the photoablation process in tumor and provided a new strategy for the surveillance of tumor in big animal models.

CONCLUSION

Altogether, the use of a large animal model in this study presented higher clinical significance as compared to previous studies.

Risk factors for anastomotic leakage after anterior resection for rectal cancer (RALAR study): A nationwide retrospective study of the Italian Society of Surgical Oncology Colorectal Cancer Network Collaborative Group

AIM

Anastomotic leakage after restorative surgery for rectal cancer shows high morbidity and related mortality. Identification of risk factors could change operative planning, with indications for stoma construction. This retrospective multicentre study aims to assess the anastomotic leak rate, identify the independent risk factors and develop a clinical prediction model to calculate the probability of leakage.

METHODS

The study used data from 24 Italian referral centres of the Colorectal Cancer Network of the Italian Society of Surgical Oncology. Patients were classified into two groups, AL (anastomotic leak) or NoAL (no anastomotic leak). The effect of patient-, disease-, treatment- and postoperative outcome-related factors on anastomotic leak after univariable and multivariable analysis was measured.

RESULTS

A total of 5398 patients were included, 552 in group AL and 4846 in group NoAL. The overall incidence of leaks was 10.2%, with a mean time interval of 6.8 days. The 30-day leak-related mortality was 2.6%. Sex, body mass index, tumour location, type of approach, number of cartridges employed, weight loss, clinical T stage and combined multiorgan resection were identified as independent risk factors. The stoma did not reduce the leak rate but significantly decreased leak severity and reoperation rate. A nomogram with a risk score (RALAR score) was developed to predict anastomotic leak risk at the end of resection.

CONCLUSIONS

While a defunctioning stoma did not affect the leak risk, it significantly reduced its severity. Surgeons should recognize independent risk factors for leaks at the end of rectal resection and could calculate a risk score to select high-risk patients eligible for protective stoma construction.

The Role of Transanal Endoscopic Surgery for Early Rectal Cancer

Transanal endoscopic surgery (TES), which is performed through a variety of transanal endoluminal multitasking surgical platforms, was developed to facilitate endoscopic en bloc excision of rectal lesions as a minimally invasive alternative to radical proctectomy. Although the oncologic safety of TES in the treatment of malignant rectal tumors has been an area of vigorous controversy over the past two decades, TES is currently accepted as an oncologically safe approach for the treatment of carefully selected early and superficial rectal cancers. TES can also serve as both a diagnostic and potentially curative treatment of partially resected unsuspected malignant polyps. In this article, indications and contraindications for transanal endoscopic excision of early rectal cancer lesions are reviewed, as well as selection criteria for the most appropriate transanal excisional approach. Preoperative preparation and surgical technique for complications of TES will be reviewed, as well as recommended surveillance and management of upstaged tumors.

Perioperative Complications After Proctectomy for Rectal Cancer: Does Neoadjuvant Regimen Matter?

OBJECTIVE

Investigate the association between neoadjuvant treatment strategy and perioperative complications in patients undergoing proctectomy for nonmetastatic rectal cancer.

SUMMARY OF BACKGROUND DATA

Neoadjuvant SC-TNT is an alternative to neoadjuvant CRT for rectal cancer. Some have argued that short-course radiation and extended radiation-to-surgery intervals increase operative difficulty and complication risk. However, the association between SC-TNT and surgical complications has not been previously investigated.

METHODS

This single-center retrospective cohort study included patients undergoing total mesorectal excision for nonmetastatic rectal cancer after SC-TNT or CRT between 2010 and 2018. Univariate analysis of severe POM and multiple secondary outcomes, including overall POM, intraoperative complications, and resection margins, was performed. Logistic regression of severe POM was also performed.

RESULTS

Of 415 included patients, 156 (38%) received SC-TNT and 259 (62%) received CRT. The cohorts were largely similar, though patients with higher tumors (69.9% vs 47.5%, P < 0.0001) or node-positive disease (76.9% vs 62.6%, P = 0.004) were more likely to receive SC-TNT. We found no difference in incidence of severe POM (9.6% SC-TNT vs 12.0% CRT, P = 0.46) or overall POM (39.7% SC-TNT vs 37.5% CRT, P = 0.64) between cohorts. Neoadjuvant regimen was also not associated with a difference in severe POM (odds ratio 0.42, 95% confidence interval 0.04-4.70, P = 0.48) in multivariate analysis. There was no significant association between neoadjuvant regimen and any secondary outcome.

CONCLUSION

In rectal cancer patients treated with SC-TNT and proctectomy, we found no significant association with POM compared to patients undergoing CRT. SC-TNT does not significantly increase the risk of POM compared to CRT.

Cost-effectiveness of Total Neoadjuvant Therapy With Short-Course Radiotherapy for Resectable Locally Advanced Rectal Cancer

IMPORTANCE

Short-course radiotherapy and total neoadjuvant therapy (SCRT-TNT) followed by total mesorectal excision (TME) has emerged as a new treatment paradigm for patients with locally advanced rectal adenocarcinoma. However, the economic implication of this treatment strategy has not been compared with that of conventional long-course chemoradiotherapy (LCCRT) followed by TME with adjuvant chemotherapy.

OBJECTIVE

To perform a cost-effectiveness analysis of SCRT-TNT vs LCCRT in conjunction with TME for patients with locally advanced rectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

A decision analytical model with a 5-year time horizon was constructed for patients with biopsy-proven, newly diagnosed, primary locally advanced rectal adenocarcinoma treated with SCRT-TNT or LCCRT. Markov modeling was used to model disease progression and patient survival after treatment in 3-month cycles. Data on probabilities and utilities were extracted from the literature. Costs were evaluated from the Medicare payer's perspective in 2020 US dollars. Sensitivity analyses were performed for key variables. Data were collected from October 3, 2020, to January 20, 2021, and analyzed from November 15, 2020, to April 25, 2021.

EXPOSURES

Two treatment strategies, SCRT-TNT vs LCCRT with adjuvant chemotherapy, were compared.

MAIN OUTCOMES AND MEASURES

Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at 3% annually. Willingness-to-pay threshold was set at $50 000/QALY.

RESULTS

During the 5-year horizon, the total cost was $41 355 and QALYs were 2.21 for SCRT-TNT; for LCCRT, the total cost was $54 827 and QALYs were 2.12, resulting in a negative incremental cost-effectiveness ratio (-$141 256.77). The net monetary benefit was $69 300 for SCRT-TNT and $51 060 for LCCRT. Sensitivity analyses using willingness to pay at $100 000/QALY and $150 000/QALY demonstrated the same conclusion.

CONCLUSIONS AND RELEVANCE

These findings suggest that SCRT-TNT followed by TME incurs lower cost and improved QALYs compared with conventional LCCRT followed by TME and adjuvant chemotherapy. These data offer further rationale to support SCRT-TNT as a novel cost-saving treatment paradigm in the management of locally advanced rectal cancer.

Effects of Neoadjuvant Radiotherapy on Postoperative Complications in Rectal Cancer: A Meta-Analysis

Objective

Neoadjuvant radiotherapy (nRT) is an important treatment approach for rectal cancer. The relationship, however, between nRT and postoperative complications is still controversial. Here, we conducted a meta-analysis to evaluate such concerns.

Methods

The electronic literature from 1983 to 2021 was searched in PubMed, Embase, and Web of Science. Postoperative complications after nRT were included in the meta-analysis. The pooled odds ratio (OR) was calculated by the random-effects model. Statistical analysis was conducted by Review Manager 5.3 and STATA 14.

Results

A total of 23,723 patients from 49 studies were included in the meta-analysis. The pooled results showed that nRT increased the risk of anastomotic leakage (AL) compared to upfront surgery (OR = 1.23; 95% CI, 1.07-1.41; p=0.004). Subgroup analysis suggested that both long-course (OR = 1.20, 95% CI 1.03-1.40; p=0.02) and short-course radiotherapy (OR = 1.25, 95% CI, 1.02-1.53; p=0.04) increased the incidence of AL. In addition, nRT was the main risk factor for wound infection and pelvic abscess. The pooled data in randomized controlled trials, however, indicated that nRT was not associated with AL (OR = 1.01; 95% CI 0.82-1.26; p=0.91).

Conclusions

nRT may increase the risk of AL, wound infection, and pelvic abscess compared to upfront surgery among patients with rectal cancer.

Updates of Risk Factors for Anastomotic Leakage after Colorectal Surgery

Anastomotic leakage is a potentially severe complication occurring after colorectal surgery and can lead to increased morbidity and mortality, permanent stoma formation, and cancer recurrence. Multiple risk factors for anastomotic leak have been identified, and these can allow for better prevention and an earlier diagnosis of this significant complication. There are nonmodifiable factors such as male gender, comorbidities and distance of tumor from anal verge, and modifiable risk factors, including smoking and alcohol consumption, obesity, preoperative radiotherapy and preoperative use of steroids or non-steroidal anti-inflammatory drugs. Perioperative blood transfusion was shown to be an important risk factor for anastomotic failure. Recent studies on the laparoscopic approach in colorectal surgery found no statistical difference in anastomotic leakage rate compared with open surgery. A diverting stoma at the time of primary surgery does not appear to reduce the leak rate but may reduce its clinical consequences and the need for additional surgery if anastomotic leakage does occur. It is still debatable if preoperative bowel preparation should be used, especially for left colon and rectal resections, but studies have shown similar incidence of postoperative leak rate.

Risk Factors for Anastomotic Leak, Consideration for Proximal Diversion, and Appropriate Use of Drains

Anastomotic leaks are a major source of morbidity after colorectal surgery. There is a myriad of risk factors that may contribute to anastomotic leaks. These risk factors can be categorized as modifiable, nonmodifiable, and intraoperative factors. Identification of these risk factors allows for preoperative optimization that may minimize the risk of anastomotic leak. Knowledge of such high-risk features may also affect intraoperative decision-making regarding the creation of an anastomosis, consideration for proximal diversion, or placement of a drain. A thorough understanding of the interplay between risk factors, indications for proximal diversion, and utility of drain placement is imperative for colorectal surgeons.