Rectal Neoplasms

This is a 5 year Phase II study to evaluate the safety of non-operative management (NOM) in patients with low rectal cancer (LRC) who achieve a complete clinical response (cCR) following chemoradiotherapy (CRT). The safety of NOM will be evaluated by assessing (i) rate of local re-growth and (ii) rate of macroscopically positive resection margin (R2) when surgery is required due to local re-growth. NOM will be considered safe or as effective as surgery to achieve local control if the rate of local re-growth is equal to or less than 30% and the rate of a macroscopically positive margin is 0%.

This study aims to evaluate the safety and effectiveness of a combination treatment including a PD-1 inhibitor (serplulimab), oncolytic virus H101, short-course radiotherapy, and XELOX chemotherapy as total neoadjuvant therapy in patients with locally advanced low rectal cancer (cT1-3N0M0). In this prospective, multicenter, single-arm phase II study, eligible patients will receive a standardized treatment regimen consisting of intratumoral injection of oncolytic virus H101, short-course radiotherapy, chemotherapy, and immunotherapy over multiple cycles. Tumor response will be assessed using imaging, endoscopy, and clinical evaluation after completion of treatment. The primary objective is to determine the 1-year clinical complete response rate. Secondary outcomes include tumor response rate, organ preservation rate, survival outcomes, and treatment safety. The results of this study may help improve treatment strategies for rectal cancer, increase the rate of complete response, and provide more opportunities for organ preservation while maintaining safety.

The Multi-OutcoMe EvaluatioN of radiation Therapy Using the Unity MR-Linac Study (MOMENTUM) is a multi-institutional, international registry facilitating evidenced based implementation of the Unity MR-Linac technology and further technical development of the MR-Linac system with the ultimate purpose to improve patients' survival, local, and regional tumor control and quality of life.

Colorectal cancer (CRC) is one of the most common and deadly cancers worldwide. About 1 in 4 people with CRC already have cancer spread (metastasis) when first diagnosed, and about half develop spread during their illness. Recent research shows that bacteria living in the gut and even within tumors might play an important role in how cancer spreads. The goal of this study is to better understand how bacteria might influence the spread of colorectal cancer. The main questions the investigators aim to answer are: Are there differences in bacteria between people whose cancer has spread and those whose cancer has not spread? Could certain bacteria help predict which cancers might spread? To answer these questions, the investigators will: Collect different types of samples from participants: Tumor tissue Normal tissue near the tumor Tissue from where cancer has spread Stool samples before surgery Study the bacteria in these samples using advanced testing methods Compare bacterial patterns between different groups People can take part in this study if they: Are between 18 and 75 years old Have colorectal cancer confirmed by doctors Have not taken antibiotics recently Do not have immune system problems This research may help us: Understand why some colorectal cancers spread Find new ways to predict which cancers might spread Develop better treatments for colorectal cancer

The goal of this study is to compare the postoperative anal function of patients with ultra-low rectal cancer after Parks operation (colon anal anastomosis) and Bacon operation (colon anal pull-out anastomosis), which may provide clinical evidence for the improvement of anal function and quality of life. The main questions it aims to answer are: the difference of anal function 1 year after surgery type of study: clinical trial participant population: patients with low rectal cancer Participants will receive Parks operation of Bacon operation If there is a comparison group: Researchers will compare Parks and Bacon operation to see if the anal function 1 year after surgery is different.

Rectal cancer (RC) is among the most prevalent gastrointestinal cancers \[1\], characterized by significant tumor heterogeneity \[2\]. Neoadjuvant chemoradiotherapy followed by total mesorectal excision is a standard treatment for locally advanced rectal cancer \[3\]. Although the locoregional recurrence rate has decreased due to this treatment, distant metachronous metastases still occur in over 20-30% of cases \[4,5\]. The varying biological characteristics of rectal cancer may result in different treatment responses and prognoses \[6\]. Patients who are diagnosed with the same tumor-node-metastasis (TNM) stage of RC frequently exhibit vastly different clinical outcomes, despite receiving the same therapeutic interventions \[7\]. While the TNM staging system remains the predominantly used framework for directing treatment choices and forecasting prognosis, it is crucial to take into account additional pathological elements, such as tumor budding, lymphovascular invasion (LVI), perineural invasion, and extramural venous invasion \[8-10\]. A recent investigation has highlighted that LVI, rather than the traditionally prioritized extent of tumor invasion, serves as a significant risk factor for metastasis in early-stage RC \[11\]. Patients exhibiting LVI+ demonstrate a considerably worse prognosis and overall survival when compared to those with LVI -. Identifying LVI before surgery is crucial for informing treatment strategies in RC \[12\]. LVI offers important information regarding the tumor's biological behavior and its likelihood of metastasizing, thus improving the precision of disease staging. This information enables clinicians to tailor treatment approaches, which helps prevent overtreatment in patients with LVI -. In cases where LVI is present, it may be essential to adopt more aggressive treatment methods, such as postoperative chemotherapy, radiotherapy, or more extensive surgical resections, to reduce the chances of recurrence and metastasis. In summary, LVI serves as a crucial prognostic factor, providing essential insights into the tumor's potential for metastasis and recurrence, which has significant clinical implications for predicting postoperative outcomes, including recurrence, metastasis, and disease-free survival. Therefore, a preoperative non-invasive assessment of LVI, particularly in patients with LVI +, may be instrumental in guiding clinical practice. Conventional magnetic resonance imaging (MRI) is particularly effective in observing large blood vessels and has moderate sensitivity and high specificity to distinguish LVI \[13\]. However, it can noninvasively and accurately assess extramural vascular invasion with a diameter greater than 3 mm. In contrast, it is challenging to evaluate vascular invasion with a diameter less than 3 mm, as well as intramural vascular and lymphatic infiltration, due to the limitations in resolution \[14,15\]. In addition, pathological biopsy is the gold standard for preoperative diagnosis. However, this invasive approach may not reflect the LVI status of the entire tumor due to possible sample errors \[16\]. Therefore, effectively assessing LVI in RC via preoperative imaging remains a significant challenge. Intravoxel incoherent motion (IVIM) is a functional imaging method that can display the diffuse movement of water molecules and blood flow, microcirculation perfusion, thereby improving the diagnostic accuracy of RC \[17,18\]. The IVIM model has the potential to identify perfusion effects using multiple b-value samples and biexponential curve fit analysis \[19\], which can lead to three parameters, namely the true diffusion coefficient (D), the pseudo-diffusion coefficient (D\*), and the perfusion fraction (f). Li et al \[20\]. discovered that the D value obtained from IVIM of LVI+ patients was significantly higher than that of LVI- patients with RC, but only 42 patients were included in this study, making it more difficult to accurately assess the feasibility of IVIM. In another study, Kan et al \[21\]. revealed that the D value was helpful to assess the prognostic factor related to RC, while the AUC of the D value for evaluating LVI was only 0.646. Currently, studies utilizing conventional IVIM quantitative parameters have demonstrated a relatively low diagnostic efficiency in detecting LVI, with AUC values ranging from 0.629 to 0.646 \[22,23\]. Tumor heterogeneity has emerged as a significant biomarker for tumor staging and prognosis \[24\]. Sub-region analysis, an innovative imaging post-processing technique, has demonstrated its potential in exploring intratumor heterogeneity in recent years. Prior research has underscored the importance of sub-region analysis derived from either single-modality or multiparametric MRI in the investigation of intratumor heterogeneity in RC \[25-27\]. However, to our knowledge, the application of sub-region analysis based on IVIM-MRI to evaluate LVI status and prognosis in patients with RC has not been reported. Thus, this study aimed to assess the fe

The purpose of this research protocol is the evaluation of the improvement of the anorectal and urogenital urinary function, alongside the postoperative quality of life after the application of pIONM in patients submitted to TME for rectal cancer.

The goal of this clinical trial is to quantify the effects of aerobic exercise training compared to attention control on intermuscular adipose tissue in colorectal cancer survivors.

This prospective observational cohort study aims to compare the clinical and procedural outcomes of Endoscopic Submucosal Dissection (ESD) and Transanal Minimally Invasive Surgery (TAMIS) for the treatment of early-stage rectal neoplasia. The study will evaluate recurrence rates, en bloc resection rates, R0 resection rates, procedure time, complication rates, and length of hospital stay over a 1-year follow-up period. Data will be collected from patients treated at multiple centers with expertise in ESD and TAMIS.

One of the standard treatment options offered to patients of locally advanced rectal cancer is neoadjuvant (treatment given before surgery) radiotherapy \& chemotherapy followed by surgery. In patients whose tumour has completely reduced after neoadjuvant treatment, the wait and watch strategy is also an option. This is another standard treatment option for patients of locally advanced rectal cancers. In this, the patient is monitored after treatment completion. In this study, investigators are only going to observe the patient's response to treatment, monitor their side-effects due to treatment and assess their quality of life using standardized quality of life questionnaires. No additional tests or hospital visits will be required as a part of this study. The patient will be followed up, as per standard follow-up protocol, for at least 2 years after the completion of their treatment.

This is a multicenter, superior, randomized controlled trial designed to compare Robotic-assisted total mesorectal excision (RATME) and laparoscopic-assisted total mesorectal excision (LATME) for middle and low rectal cancer. The primary endpoint is the incidence of intersphincteric resection (ISR). The secondary outcomes are coloanal anastomosis (CAA), conversion to open, conversion to transanal TME (TaTME), incidence of abdominoperineal resection (APR), postoperative morbidity and mortality within 30 days after surgery, pathological outcomes, long-term survival outcomes, functional outcomes, and quality of life.

A Clinical and Biological Database will provide to the scientific community a collection of blood and tissues with clinical data to improve knowledge about cancer and help to develope new cancer treatments. This database is specific to Rectum Cancer.

The purpose of this protocol is to compare neoadjuvant chemoradiation plus consolidation chemotherapy before surgical resection with the standard neoadjuvant chemoradiation followed by surgical resection and adjuvant chemotherapy in patients with rectal cancer.

Study Purpose: This study aims to understand how pelvic floor rehabilitation (PFR) after low anterior resection (LAR) surgery for rectal cancer affects bowel control and quality of life compared to usual care. Background: Rectal cancer and its treatments can significantly impact patients' lives, often causing bowel issues like frequent bowel movements, urgency, and incontinence. These problems, known as low anterior resection syndrome (LARS), affect 70-90% of patients and can last for over two years. (1,2) Current Knowledge: Advances in treatments have improved survival rates and recovery. Despite improvements, many patients still experience bowel issues after surgery. Past studies show PFR can help, but they have limitations like small sample sizes and varied methods. (3-5) Need for the Study: There is a need for a well-designed study to confirm the benefits of PFR and to identify which patients benefit the most. Study Design: This study is a randomized controlled trial that will: * Compare PFR to usual care in patients after LAR surgery. * Focus on bowel control and quality of life. * Provide detailed insights to improve aftercare for rectal cancer patients.

Currently, there is no prediction scale available to identify patients with rectal neoplasms as technically complex in the middle and lower thirds; that is, those who are at high risk of affected circumferential margins and low quality of the mesorectum. The application of a predictive model that allows preoperative identification of the group of patients in whom optimal results in mesorectal quality and circumferential margin are less likely to be obtained through laparoscopic or minimally invasive surgery would enable the selection of patients who will require and justify all efforts and healthcare resources to improve surgical outcomes. Therefore, the investigators aim to create a predictive model to identify these patients, allowing the discrimination of which patients will benefit from different techniques, or even which ones would be opportune to initially consider an open approach.

This is an open-label, multi-center, single-arm clinical study. All patients received concurrent chemoradiation therapy (CRT) followed by 4 cycles of tislelizumab combined with CAPOX, then underwent clinical response assessment. Patients who achieved CR (cCR+ pCR confirmed by local resection of ncCR) continue tislelizumab combined with CAPOX for another 4 cycles and tislelizumab for 9 cycles, then Watch and Wait. Patients who did not achieved CR underwent total mesorectal excision (TME).

This study aimed at comparing the Comprehensive Complication Index (CCI), readmission rates, postoperative hospitalization days, duration of bearing the stoma (months), hospitalization costs, the number of hospitalizations with ghost ileostomy group versus no ileostomy group after total mesorectal excision for rectal cancer.

A national cohort study with all patients scheduled for neoadjuvant treatment with (chemo)radiotherapy or short course radiotherapy with delayed surgery 6-8 weeks) for rectal cancer staged as cT4bNX/anycTanycN and cMRF+/anycTanycN and lateral lymph nodes on MRI (and patients that have been offered short course raditotherapy with delayed surgery due to various reasons). The tumours are positioned midrectal or low and are palpable with the finger. The patients offered this treatment after recommendations on their local multidisciplinary tumour board will be will be informed and offered to participate in the study. Patients scheduled for short course radiotherapy with immediate surgery cannot be included.

This study aims to evaluate the efficacy and safety of tislelizumab combined with simultaneous integrated boost intensity-modulated radiotherapy in treating locally advanced rectal cancer. To explore a new PD-1 inhibitor adjuvant chemotherapy model combined with radiotherapy to treat locally advanced rectal cancer.

To investigate the effects of intersphincteric resection (ISR) of ultra-low rectal tumor on the brain-rectoanal function of patients, and to precisely localize the cerebral functional regulatory regions for intervention targets of anorectal remodeling. Utilizing transcranial magnetic stimulation(TMS) technology to explore the functional remodeling of the "new" anorectal muscle groups and provide a theoretical basis for more research on the rehabilitation and mechanism of fecal incontinence.

The purpose of this study is to compare the efficacy, prognosis, health economics of different treatment modalities of mid-low rectal cancer in different centers in China, and to conduct cost utility analysis (CUA) on the treatment process of rectal cancer to explore the best treatment modality that meets the actual need of medical units in each region and at each level. The investigators hope to provide evidence-based medical suggestions for medical quality control of rectal cancer and revision of clinical guidelines, and provides a source of decision making for medical management and medical insurance.

Non-randomized study of robot-assisted perineal reconstruction with rectus abdominis muscle flap in patients operated with abdominoperineal resection for irradiated locally advanced rectal or anal cancer. Operative time, complications, wound healing, pre- and postoperatively abdominal wall strength and patient related outcomes including sexual health will be registered.