R2* mapping and reduced field-of-view diffusion-weighted imaging for preoperative assessment of nonenlarged lymph node metastasis in rectal cancer.

The aim of the current study is to investigate the diagnostic value of R2* mapping versus reduced field-of-view diffusion-weighted imaging (rDWI) of the primary lesion of rectal cancer for preoperative prediction of nonenlarged lymph node metastasis (NLNM). Eighty-one patients with pathologically confirmed rectal cancer underwent preoperative R2* mapping and rDWI sequences before total mesorectal excisions and accompanying regional lymph node dissections. Two radiologists independently performed whole-tumor measurements of R2* and apparent diffusion coefficient (ADC) parameters on primary lesions of rectal cancer. Patients were divided into positive (NLNM+) and negative (NLNM-) groups based on their pathological analysis. The tumor location, maximum diameter of the tumor, and maximum short diameter of the lymph node were assessed. R2* and ADC, pT stage, tumor grade, status of mesorectal fascia, and extramural vascular invasion were also studied for their potential relationships with NLNM using multivariate logistic regression analysis. The NLNM+ group had significantly higher R2* (43.56 ± 8.43 vs. 33.87 ± 9.57, p < 0.001) and lower ADC (1.00 ± 0.13 vs. 1.06 ± 0.22, p = 0.036) than the NLNM- group. R2* and ADC were correlated to lymph node metastasis (r = 0.510, p < 0.001 for R2*; r = -0.235, p = 0.035 for ADC). R2* and ADC showed good and moderate diagnostic abilities in the assessment of NLNM status with corresponding area-under-the-curve values of 0.795 and 0.636. R2* provided a significantly better diagnostic performance compared with ADC for the prediction of NLNM status (z = 1.962, p = 0.0498). The multivariate logistic regression analysis demonstrated that R2* was a compelling factor of lymph node metastasis (odds ratio = 56.485, 95% confidence interval: 5.759-554.013; p = 0.001). R2* mapping had significantly higher diagnostic performance than rDWI from the primary tumor of rectal cancer in the prediction of NLNM status.

Utility of abbreviated MRI in the post-treatment evaluation of rectal cancer.

BACKGROUND: Post-treatment evaluation of patients with rectal cancer (RC) using magnetic resonance imaging (MRI) burdens medical resources, necessitating an exploration of abbreviated protocols. PURPOSE: To evaluate the diagnostic performance of abbreviated MRI (A-MRI) for the post-treatment evaluation of RC patients. MATERIAL AND METHODS: This retrospective study included RC patients who underwent non-contrast rectal MRI and standard liver MRI, as well as abdominal contrast-enhanced computed tomography (CECT) for post-treatment evaluation. A-MRI comprised diffusion-weighted imaging (DWI) and T2-weighted imaging of the upper abdomen and the pelvic cavity. Three radiologists independently reviewed A-MRI, CECT, and standard liver MRI in the detection of viable disease. The diagnostic performances were compared using a reference standard considering all available information, including pathology, FDG-PET, endoscopic results, and clinical follow-up. RESULTS: We included 78 patients (50 men, 28 women; mean age=60.9 ± 10.2 years) and observed viable disease in 34 (43.6%). On a per-patient-basis analysis, A-MRI showed significantly higher sensitivity (95% vs. 81%, P = 0.04) and higher accuracy (93% vs. 82%, P < 0.01), compared to those of CECT, while A-MRI showed comparable sensitivity (91% vs. 91%, P = 0.42) and accuracy (97% vs. 98%, P = 0.06) to that of standard liver MRI. On a per-lesion-based analysis, A-MRI exhibited significantly superior lesion detectability than that of CECT (figure of merit 0.91 vs. 0.77, P < 0.01) and comparable to that of standard liver MRI (figure of merit 0.91 vs. 0.92, P = 0.75). CONCLUSION: A-MRI exhibited higher sensitivity and diagnostic accuracy than those of CECT in the post-treatment evaluation of RC, while it showed comparable performances with standard liver MRI. A-MRI provides diagnostic added value in the follow-up of RC patients.

Preoperative sequential short-course radiation therapy and FOLFOX chemotherapy versus long-course chemoradiotherapy for locally advanced rectal cancer: a multicenter, randomized controlled trial (SOLAR trial).

BACKGROUND: Preoperative (chemo)radiotherapy has been widely used as an effective treatment for locally advanced rectal cancer (LARC), leading to a significant reduction in pelvic recurrence rates. Because early administration of intensive chemotherapy for LARC has more advantages than adjuvant chemotherapy, total neoadjuvant therapy (TNT) has been introduced and evaluated to determine whether it can improve tumor response or treatment outcomes. This study aims to investigate whether short-course radiotherapy (SCRT) followed by intensive chemotherapy improves oncologic outcomes compared with traditional preoperative long-course chemoradiotherapy (CRT). METHODS: A multicenter randomized phase II trial involving 364 patients with LARC (cT3-4, cN+, or presence of extramural vascular invasion) will be conducted. Patients will be randomly assigned to the experimental or control arm at a ratio of 1:1. Participants in the experimental arm will receive SCRT (25 Gy in 5 fractions, daily) followed by four cycles of FOLFOX (oxaliplatin, 5-fluorouracil, and folinic acid) as a neoadjuvant treatment, and those in the control arm will receive conventional radiotherapy (45-50.4 Gy in 25-28 fractions, 5 times a week) concurrently with capecitabine or 5-fluorouracil. As a mandatory surgical procedure, total mesorectal excision will be performed 2-5 weeks from the last cycle of chemotherapy in the experimental arm and 6-8 weeks after the last day of radiotherapy in the control arm. The primary endpoint is 3-year disease-free survival, and the secondary endpoints are tumor response, overall survival, toxicities, quality of life, and cost-effectiveness. DISCUSSION: This is the first Korean randomized controlled study comparing SCRT-based TNT with traditional preoperative LC-CRT for LARC. The involvement of experienced colorectal surgeons ensures high-quality surgical resection. SCRT followed by FOLFOX chemotherapy is expected to improve disease-free survival compared with CRT, with potential advantages in tumor response, quality of life, and cost-effectiveness. TRIAL REGISTRATION: This trial is registered at Clinical Research Information under the identifier Service KCT0004874 on April 02, 2020, and at Clinicaltrial.gov under the identifier NCT05673772 on January 06, 2023.

Pretreatment MRI-detected extramural venous invasion as a prognostic and predictive biomarker for neoadjuvant chemoradiotherapy in non-metastatic rectal cancer: a propensity score matched analysis.

OBJECTIVES: This study evaluated pretreatment magnetic resonance imaging (MRI)-detected extramural venous invasion (pmrEMVI) as a predictor of survival after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC). MATERIALS AND METHODS: Medical records of 1184 patients with rectal adenocarcinoma who underwent TME between January 2011 and December 2016 were reviewed. MRI data were collected from a computerized radiologic database. Cox proportional hazards analysis was used to assess local, systemic recurrence, and disease-free survival risk based on pretreatment MRI-assessed tumor characteristics. After propensity score matching (PSM) for pretreatment MRI features, nCRT therapeutic outcomes according to pmrEMVI status were evaluated. Cox proportional hazards analysis was used to identify risk factors for early recurrence in patients receiving nCRT. RESULTS: Median follow-up was 62.8 months. Among all patients, the presence of pmrEMVI was significantly associated with worse disease-free survival (DFS; HR 1.827, 95% CI 1.285-2.597, p = 0.001) and systemic recurrence (HR 2.080, 95% CI 1.400-3.090, p < 0.001) but not local recurrence. Among patients with pmrEMVI, nCRT provided no benefit for oncological outcomes before or after PSM. Furthermore, pmrEMVI( +) was the only factor associated with early recurrence on multivariate analysis in patients receiving nCRT. CONCLUSIONS: pmrEMVI is a poor prognostic factor for DFS and SR in patients with non-metastatic rectal cancer and also serves as a predictive biomarker of poor DFS and SR following nCRT in LARC. Therefore, for patients who are positive for pmrEMVI, consideration of alternative treatment strategies may be warranted. CLINICAL RELEVANCE STATEMENT: This study demonstrated the usefulness of pmrEMVI as a predictive biomarker for nCRT, which may assist in initial treatment decision-making in patients with non-metastatic rectal cancer. KEY POINTS: • Pretreatment MRI-detected extramural venous invasion (pmrEMVI) was significantly associated with worse disease-free survival and systemic recurrence in patients with non-metastatic rectal cancer. • pmrEMVI is a predictive biomarker of poor DFS following nCRT in patients with LARC. • The presence of pmrEMVI was the only factor associated with early recurrence on multivariate analysis in patients receiving nCRT.

External validation and comparison of MR-based radiomics models for predicting pathological complete response in locally advanced rectal cancer: a two-centre, multi-vendor study.

OBJECTIVES: The aim of this study was two-fold: (1) to develop and externally validate a multiparameter MR-based machine learning model to predict the pathological complete response (pCR) in locally advanced rectal cancer (LARC) patients after neoadjuvant chemoradiotherapy (nCRT), and (2) to compare different classifiers' discriminative performance for pCR prediction. METHODS: This retrospective study includes 151 LARC patients divided into internal (centre A, n = 100) and external validation set (centre B, n = 51). The clinical and MR radiomics features were derived to construct clinical, radiomics, and clinical-radiomics model. Random forest (RF), support vector machine (SVM), logistic regression (LR), K-nearest neighbor (KNN), naive Bayes (NB), and extreme gradient boosting (XGBoost) were used as classifiers. The predictive performance was assessed using the receiver operating characteristic (ROC) curve. RESULTS: Eleven radiomics and four clinical features were chosen as pCR-related signatures. In the radiomics model, the RF algorithm achieved 74.0% accuracy (an AUC of 0.863) and 84.4% (an AUC of 0.829) in the internal and external validation sets. In the clinical-radiomics model, RF algorithm exhibited high and stable predictive performance in the internal and external validation datasets with an AUC of 0.906 (87.3% sensitivity, 73.7% specificity, 76.0% accuracy) and 0.872 (77.3% sensitivity, 88.2% specificity, 86.3% accuracy), respectively. RF showed a better predictive performance than the other classifiers in the external validation datasets of three models. CONCLUSIONS: The multiparametric clinical-radiomics model combined with RF algorithm is optimal for predicting pCR in the internal and external sets, and might help improve clinical stratifying management of LARC patients. KEY POINTS: • A two-centre study showed that radiomics analysis of pre- and post-nCRT multiparameter MR images could predict pCR in patients with LARC. • The combined model was superior to the clinical and radiomics model in predicting pCR in locally advanced rectal cancer. • The RF classifier performed best in the current study.

Risk and survival in colorectal cancer with increasing body mass index: A nationwide population-based cohort study.

AIM: The aim was to explore potential associations between the body mass index (BMI) and the risk of colorectal cancer (CRC), including subsites of the colon, and cancer-specific death. METHODS: A registry-based cohort study was conducted with baseline data gathered from the Norwegian Tuberculosis Screening Programme, collected between 1963 and 1975, and linked to follow-up data from the Cancer Registry of Norway and the Norwegian Cause of Death Registry. Cox regression models were used to explore associations between BMI and CRC risk and cancer-specific death. RESULTS: Of 1 723 692 included individuals, 76 616 developed CRC during 55 370 707 person-years of follow-up. In men, a 5 kg/m2 increase in BMI was associated with an increased risk of colon cancer, including both right and left subsites, and rectal cancer. Allowing for nonlinearities, we found a U-shaped association for the right colon and an inverse U-shape for the left colon and rectum cancer. In women, a 5 kg/m2 increase in BMI in early adulthood was associated with increased risk of colon cancer, including both subsites. In women, an increased risk of CRC death with increasing BMI was found for colon cancer. CONCLUSIONS: Men of all ages have an increased risk of CRC with increasing BMI, with the highest risk for right-sided colon cancer. An increased risk for colon cancer was also found in women with high BMI in early adulthood. Furthermore, women of all age groups appeared to have an increased risk of CRC death with higher BMI.

A Deep Learning Model Based on MRI and Clinical Factors Facilitates Noninvasive Evaluation of KRAS Mutation in Rectal Cancer.

BACKGROUND: Recent studies showed the potential of MRI-based deep learning (DL) for assessing treatment response in rectal cancer, but the role of MRI-based DL in evaluating Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation remains unclear. PURPOSE: To develop a DL method based on T2-weighted imaging (T2WI) and clinical factors for noninvasively evaluating KRAS mutation in rectal cancer. STUDY TYPE: Retrospective. SUBJECTS: A total of 376 patients (108 women [28.7%]) with histopathology-confirmed rectal adenocarcinoma and KRAS mutation status. FIELD STRENGTH/SEQUENCE: A 3 T, turbo spin echo T2WI and single-shot echo-planar diffusion-weighted imaging (b = 0, 1000 sec/mm2 ). ASSESSMENT: A clinical model was constructed with clinical factors (age, gender, carcinoembryonic antigen level, and carbohydrate antigen 199 level) and MRI features (tumor length, tumor location, tumor stage, lymph node stage, and extramural vascular invasion), and two DL models based on modified MobileNetV2 architecture were evaluated for diagnosing KRAS mutation based on T2WI alone (image model) or both T2WI and clinical factors (combined model). The clinical usefulness of these models was evaluated through calibration analysis and decision curve analysis (DCA). STATISTICAL TESTS: Mann-Whitney U test, Chi-squared test, Fisher's exact test, logistic regression analysis, receiver operating characteristic curve (ROC), Delong's test, Hosmer-Lemeshow test, interclass correlation coefficients, and Fleiss kappa coefficients (P < 0.05 was considered statistically significant). RESULTS: All the nine clinical-MRI characteristics were included for clinical model development. The clinical model, image model, and combined model in the testing cohort demonstrated good calibration and achieved areas under the curve (AUCs) of 0.668, 0.765, and 0.841, respectively. The combined model showed improved performance compared to the clinical model and image model in two cohorts. DCA confirmed the higher net benefit of the combined model than the other two models when the threshold probability is between 0.05 and 0.85. DATA CONCLUSION: The proposed combined DL model incorporating T2WI and clinical factors may show good diagnostic performance. Thus, it could potentially serve as a supplementary approach for noninvasively evaluating KRAS mutation in rectal cancer. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Symptoms and diagnosis of local recurrence after rectal cancer treatment.

AIM: The prognosis for local recurrence after rectal cancer treatment is poor. A minority of patients are eligible for surgery with curative intent, which could possibly be improved by earlier detection. The aim of this study was to determine symptoms at presentation and how local recurrence was diagnosed, and to identify alarm symptoms for local recurrence as opposed to symptoms found among patients after surgery for rectal cancer in general. METHODS: In a population-based retrospective cohort (cohort A), all patients who had undergone resection surgery for rectal cancer in the region of Västra Götaland, Sweden, diagnosed 2010-2014, were identified through the Swedish ColoRectal Cancer Registry. After a follow-up period of at least five years, medical records were reviewed to identify patients diagnosed with local recurrence. Data on symptoms, diagnostic procedures and treatment of local recurrence were retrieved. A prospective cohort of patients who had undergone surgery for rectal cancer without local recurrence (the QoLiRECT-study, cohort B) was used for comparison regarding symptoms at two years after treatment. RESULTS: Cohort A consisted of 1208 patients, out of whom 78 (6%) were diagnosed with local recurrence. Forty-six patients were diagnosed between scheduled follow-up visits. Fifty-eight patients were symptomatic at the time of diagnosis, and the most common symptoms were pain, bleeding and urogenital symptoms. Pain was more common in patients with local recurrence when comparing cohort A with cohort B. CONCLUSION: A majority of patients with local recurrence were diagnosed outside of the scheduled follow-up. Most of the patients were symptomatic at diagnosis. Symptoms were common in patients after rectal cancer surgery in general, however pain was more common in patients with local recurrence and could represent an alarm symptom.

The number of cycles of adjuvant chemotherapy in stage III and high-risk stage II rectal cancer: a nomogram and recursive partitioning analysis.

OBJECTIVE: The prognostic role of the number of cycles of adjuvant chemotherapy (ACT) after total mesorectal excision in stage III and high-risk stage II rectal cancer is unknown. As a result of this, our study was designed to assess the effect of the number of cycles of ACT on the prediction of cancer-specific survival. METHODS: Four hundred patients that were diagnosed as stage III and high-risk stage II rectal cancer from January 2012 to January 2018 and who had received total mesorectal excision were enrolled in this study. A nomogram incorporating the number of cycles of ACT was also developed in this study. For internal validation, the bootstrap method was used and the consistency index was used to evaluate the accuracy of the model. The patients were stratified into risk groups according to their tumor characteristics by recursive partitioning analysis. RESULTS: We found that the risk of death was decreased by 26% (HR = 0.74, 95% CI: 0.61-0.89, P = 0.0016) with each increasing ACT cycle. The N stage, positive lymph node ratio (PLNR), carcinoembryonic antigen, neutrophil-to-lymphocyte ratio, and the number of cycles of ACT were chosen and entered into the nomogram model. Recursive partitioning analysis-based risk stratification revealed a significant difference in the prognosis in rectal cancer patients with high-risk, intermediate-risk, and low-risk (3-year cancer-specific survival: 0.246 vs. 0.795 vs. 0.968, P < 0.0001). Seven or more cycles of ACT yielded better survival in patients with PLNR ≥ 0.28 but not in patients with PLNR < 0.28. CONCLUSION: In conclusion, the nomogram prognosis model based on the number of cycles of ACT predicted individual prognosis in rectal cancer patients who had undergone total mesorectal excision. These findings further showed that in patients with PLNR ≥ 0.28, no fewer than 7 cycles of ACT are needed to significantly reduce the patient's risk of death.

Preoperative Group Consultation Prior to Surgery for Colorectal Cancer-an Explorative Study of a New Patient Education Method.

Patients with colorectal cancer may lack information about the disease and treatment. In 2017, a group consultation before start of surgery was introduced at a university hospital in western Sweden to inform about the disease, treatment, and ongoing scientific studies. The primary aim of this study was to explore the experience of the patients attending the group consultation. Based on semi-structured interviews with patients with colorectal cancer, a questionnaire was constructed and administered to patients, both those attending and those not attending the group consultation. In total, 124 patients were included and the response rate was 86%. A majority of patients attending the group consultation would recommend it to someone else with the same illness. Of the patients attending the group consultation, 81% (30/37) patients agreed, fully or partially, that attending the group consultation had increased their sense of control and 89% (33/37) that the information they received at the group consultation increased their feeling of participation in the treatment. Preoperative group consultation is a feasible modality for informing and discussing the upcoming treatment for colorectal cancer with the patients, and the patients who attended the group setting appreciated it. Attending the group consultation increased the patients' feeling of active participation in their treatment and their sense of control, which could possibly both improve their experience of their illness and facilitate recovery. CLINICALTRIALS.GOV IDENTIFIER: NCT03888313.

Psychometric validation of the Moroccan version of the EORTC QLQ-C30 in colorectal Cancer patients: cross-sectional study and systematic literature review.

BACKGROUND: Health-related quality of life is mainly impacted by colorectal cancer which justified the major importance addressed to the development and validation of assessment questionnaires. We aimed to assess the validity and reliability of the Moroccan Arabic Dialectal version of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Core Questionnaire (QLQ-C30) in patients with colorectal cancer. METHODS: We conducted a cross-sectional study using the Moroccan version of the EORTC QLQ-C30 on colorectal cancer patients from the National Oncology Institute of Rabat, in the period from February 2015 to June 2017. The QLQ-C30 was administered to 120 patients. Statistical analysis included reliability, convergent, and discriminant validity as well as known-groups comparisons. RESULTS: In total, 120 patients with colorectal cancer were included in the study with 38 (32%) patients diagnosed with colon cancers. Eighty-two patients (68%) had rectal cancer, among which 29 (24%) patients with a stoma. The mean age of diagnosis was 54 years (+/- 13.3). The reliability and validity of the Arabic dialectal Moroccan version of the EORTC QLQ-C30 were satisfactory. [Cronbach's alpha (α =0.74)]. All items accomplished the criteria for convergent and discriminant validity except for question number 5, which did not complete the minimum required correlation with its own scale (physical functioning). Patients with rectal cancer presented with bad Global health status and quality of life (GHS/QOL), emotional functioning as well as higher fatigue symptoms compared to patients with colon cancer. The difference between patients with and without stoma was significant for diarrhea and financial difficulty. CONCLUSIONS: The Moroccan Arabic Dialectal version of the QLQ-C30 is a valid and reliable measure of health-related quality of life (HRQOL) in patients with colorectal cancer.

Three-dimension amide proton transfer MRI of rectal adenocarcinoma: correlation with pathologic prognostic factors and comparison with diffusion kurtosis imaging.

OBJECTIVES: To investigate the utility of 3D amide proton transfer (APT) MRI in predicting pathologic factors for rectal adenocarcinoma, in comparison with diffusion kurtosis imaging. METHODS: Sixty-one patients with rectal adenocarcinoma were enrolled in this prospective study. 3D APT and diffusion kurtosis imaging (DKI) were performed. Mean APT-weighted signal intensity (APTw SI), mean kurtosis (MK), mean diffusivity (MD), and ADC values of tumors were calculated on these maps. Pathological analysis included WHO grades, pT stages, pN stages, and extramural venous invasion (EMVI) status. Student's t test, Spearman correlation, and receiver operating characteristics (ROC) analysis were used for statistical analysis. RESULTS: High-grade rectal adenocarcinoma showed significantly higher mean APTw SI and MK values (2.771 ± 0.384 vs 2.108 ± 0.409, 1.167 ± 0.216 vs 1.045 ± 0.175, respectively; p < 0.05). T3 rectal adenocarcinoma demonstrated higher mean APTw SI and MK than T2 tumors (2.433 ± 0.467 vs 1.900 ± 0.302, p < 0.05). No kurtosis, diffusivity, and ADC differences were found between T2 and T3 tumors. Tumors with lymph node metastasis and EMVI involvement showed significantly higher mean APTw SI, MK. No difference was found in diffusivity and ADC between pN0 and pN1-2 groups, and EMVI-negative and EMVI-positive statuses. Mean APTw SI exhibited a significantly high positive correlation with WHO grades, demonstrating 92.31% sensitivity and 79.17% specificity for distinguishing low- from high-grade rectal adenocarcinoma, providing a better diagnostic capacity than MK, MD, and mean ADC values. CONCLUSION: 3D-APT could serve as a non-invasive biomarker for evaluating prognostic factors of rectal adenocarcinoma. KEY POINTS: • Mean APTw SI was significantly higher in high-grade compared to low-grade rectal adenocarcinoma. • Mean APTw SI was significantly higher in T3 stage rectal adenocarcinoma, with lymph node metastasis, or in EMVI-positive status. • APTw SI exhibited greater diagnostic capability in discriminating low-grade from high-grade rectal adenocarcinoma, compared with kurtosis, diffusivity, and ADC.

Detection of distant metastases in rectal cancer: contrast-enhanced CT vs whole body MRI.

OBJECTIVES: To evaluate the diagnostic performance of whole-body MRI (WB-MRI) including contrast-enhanced T1-weighted imaging (T1WI) and WB-DWI in rectal cancer initial staging. METHODS: This retrospective study was approved by the IRB and the requirement of informed consent was waived. From September 2013 to Feb 2015, patients who underwent rectal MRI including WB-MRI, as well as chest and abdominopelvic CT for initial staging, were included. WB-MRI consisted of contrast-enhanced T1-weighted imaging and DWI covering neck to the pelvis. Three radiologists reviewed WB-MRI and CECT independently for the M-classification. The diagnostic performance of CECT and WB-MRI was compared using a reference standard incorporating histology, FDG-PET results, and clinical follow-up. RESULTS: A total of 139 patients (male:female = 89:50, mean age 63.2 ± 12.4 years) were included and metastasis was observed in 15.2% (21/139). WB-MRI showed significantly higher specificity (96.7% [114/118] vs. 85.6% [101/118], p = 0.001) and positive predictive value (PPV) (80% [16/20] vs. 48.5% [16/33], p < 0.001) than CECT. However, there were no significant differences in sensitivity (76.2% [16/21] for both, p > 0.99) and negative predictive value (95.3% [101/106] at CECT vs. 95.8% [114/119] at WB-MRI, p = 0.77) between CECT and WB-MRI. CONCLUSIONS: WB-MRI showed higher specificity and PPV than CECT in newly diagnosed rectal cancer. Adding WB-MRI to standard rectal MRI is a feasible option for initial staging workup of rectal cancer. KEY POINTS: • WB-MRI showed a higher specificity and PPV than those of CECT for identifying metastasis at initial staging workup of rectal cancer. • WB-MRI and CECT did not show a significant difference in sensitivity and NPV for the M-classification. • WB-MRI can be used as an alternative to CECT for the initial M-classification modality in newly diagnosed rectal cancer.

Robotic rectal surgery: Outcomes of the first 102 totally robotic cases handled using the single-docking technique in a reference institution.

BACKGROUND AND OBJECTIVE: Rectal cancer is often surgically treated, but it is still associated with morbidity rates. Minimally invasive techniques are increasingly being used to reduce complications, and the use of such techniques can be found in the literature. This study aims to report our experience in a reference oncology center. METHODS: A retrospective cohort study was performed on a prospective database of patients who underwent robotic surgery for rectal cancer using the single-docking technique from September 2014 to April 2018. Clinical and surgical variables, as well as morbidity and mortality rates, were analyzed. RESULTS: One hundred and two patients underwent robotic surgery. Intraoperative complications occurred in six patients (4.9%), and postoperative complications in 24 patients (23.5%), of which anastomotic fistula represented 3.9%. The conversion rate was 1.96%. Two cases (1.9%) faced death within 30 days. The median length of hospitalization was 3 days. The median number of lymph nodes dissected was 15. Clinical and surgical data were correlated with postoperative complications, and no statistically significant differences were found. CONCLUSION: Robotic surgery is a safe and feasible approach to manage rectal cancer. The method presents satisfactory results with regard to the rate of operative complications, conversion rate, oncologic outcomes, and length of hospitalization.

Comparison of endoscopic therapies for rectal neuroendocrine tumors: endoscopic submucosal dissection with myectomy versus endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) has been a valuable treatment of choice for rectal neuroendocrine tumors (NETs). However, the vertical margin may remain positive after ESD because the neuroendocrine tumors develop in a submucosal tumor (SMT)-like way. Endoscopic submucosal dissection with myectomy (ESD-ME), a new method for rectal NETs, may overcome this problem. METHODS: From August 2013 to August 2020, the medical records of 69 patients (72 rectal neuroendocrine tumors) who received endoscopic submucosal dissection (ESD) or endoscopic submucosal dissection with myectomy (ESD-ME) for rectal NETs were investigated retrospectively. The characteristics of the patients and tumors, the rate of complete resection, and the rate of complications were analyzed retrospectively. RESULTS: The ESD-ME group contained 27 patients (12 males, 15 females; age range 29-72 years) and the ESD group contained 42 patients (21 males, 21 females; age range 29-71 years). Both groups had similar mean rectal neuroendocrine tumor diameters (ESD-ME 6.1 ± 1.8 mm, ESD 6.7 ± 2.6 mm; P = 0.219). The procedure time was not different significantly between groups (ESD-ME 21.1 ± 6.3, ESD 19.3 ± 3.1; P = 0.115). The endoscopic complete resection rate did not differ significantly between the ESD-ME and ESD groups (100% for each). The histological complete resection rate was 100% (27 of 27) in the ESD-ME group and 81.0% (34 of 42) in the ESD group (P = 0.043). Delayed bleeding occurred in 1 ESD-ME patient (3.7%) and in 2 ESD patients (4.8%) (P = 1.000). Perforation occurred in 1 ESD-ME patient (3.7%) and the patient was successfully managed by conservative measure, and there was no perforation after ESD (P = 0.391). CONCLUSIONS: When compared with ESD, ESD-ME resulted in a higher histological complete resection rate, had a similar complication rate, and took similar time to perform. ESD-ME can be considered an effective and safe resection method for rectal NETs < 16 mm in diameter without metastasis.

Factors contributing to time to diagnosis in symptomatic colorectal cancer: A scoping review.

INTRODUCTION: Colorectal cancer (CRC) is the third most common cancer worldwide (Ferlay et al., 2015, International Journal of Cancer, 136, E359), and delayed diagnosis is associated with mortality (Tørring et al., 2011, British Journal of Cancer, 104, 934; Tørring et al., 2012, Journal of Clinical Epidemiology, 65, 669). The purpose of this review was to determine the factors associated with time to diagnosis in symptomatic CRC using scoping review methods. METHODS: We performed database and citation searches to identify studies which examine the length of any interval from symptom presentation to diagnosis. Study selection was conducted by two independent reviewers. Factors contributing to time to diagnosis were extracted from selected articles and mapped onto a conceptual framework consisting of four levels: patient and disease factors, provider factors, organisation/setting factors and sectors of influence. RESULTS: From the 31 studies included in this review, we identified 138 unique factors, 17 of which were investigated by at least three studies and 11 of which had consistent results. Patient and disease factors were most commonly studied. Patient perception that their symptoms were benign, a non-urgent referral, female sex and rectal tumour location were each associated with a longer time to diagnosis. CONCLUSION: Thus far, the literature has focused on patient or disease-related factors, while other levels of influence have been relatively understudied.

Preoperative chemoradiotherapy affects postoperative outcomes and functional results in patients treated with transanal endoscopic microsurgery for rectal neoplasms.

BACKGROUND: The aim of this study was to quantify the incidence of short-term postoperative complications and functional disorders at 1 year from transanal endoscopic microsurgery (TEM) for rectal neoplasms, to compare patients treated with TEM alone and with TEM after preoperative chemoradiotherapy (CRT) and to analyse factors influencing postoperative morbidity and functional outcomes. METHODS: A retrospective study was conducted on all patients treated with TEM for rectal neoplasms at our institution in January 2000-December 2017. Data from a prospectively maintained database were retrospectively analysed. Patients were divided into two groups: adenoma or early rectal cancer (no CRT group) and locally advanced extraperitoneal rectal cancer with major or complete clinical response after preoperative CRT (CRT group). Short-term postoperative mortality and morbidity and the functional results at 1 year were recorded. The two groups were compared, and a statistical analysis of factors influencing postoperative morbidity and functional outcomes was performed. Functional outcome was also evaluated with the low anterior resection syndrome (LARS) score (0-20 no LARS, 21-29 minor LARS and 30-42 major LARS). RESULTS: One hundred and thirteen patients (71 males, 42 females, median age 64 years [range 41-80 years]) were included in the study (46 in the CRT group). The overall postoperative complication rate was 23.0%, lower in the noCRT group (p < 0.001), but only 2.7% were grade ≥ 3. The most frequent complication was suture dehiscence (17.6%), which occurred less frequently in the noCRT group (p < 0.001). At 1 year from TEM, the most frequent symptoms was urgency (11.9%, without significant differences between the CRT group and the noCRT group); the noCRT group experienced a lower rate of soiling than the CRT group (0% vs. 7.7%; p: 0.027). The incidence of LARS was evaluated in 47 patients from May 2012 on and was 21.3% occurring less frequently in the noCRT group (10% vs. 41.2%; p: 0.012). Only 6.4% of the patients evaluated experienced major LARS. In multivariate analysis, preoperative CRT significantly worsened postoperative morbidity and functional outcomes. CONCLUSIONS: TEM is a safe procedure associated with only low risk of severe postoperative complications and major LARS. Preoperative CRT seems to increase the rate of postoperative morbidity after TEM and led to worse functional outcomes at 1 year after surgery.

A prospective study of health related quality of life, bowel and sexual function after TaTME and conventional laparoscopic TME for mid and low rectal cancer.

BACKGROUND: The aim of our study was to evaluate short -term (3 months) and medium-term (12 months) postoperative effects on health related quality of life (HRQoL), bowel and sexual function after transanal total mesorectal excision (TaTME)  in comparison with conventional laparoscopic total mesorectal excision (TME). METHODS: A prospective study was conducted on consecutive patients who had conventional laparoscopic TME and TaTME at our institution from November 2014 to December 2018.We evaluated HRQoL and bowel function using validated scales including the European Organization for Research and Treatment of Cancer Quality of Life of colorectal cancer specific module (EORTC-QLQ-CR29), International Index of Erectile Function (IIEF-5), Female Sexual Function Index (FSFI), low anterior resection syndrome (LARS) score and Wexner score. Patients were matched one-to-one through propensity score matching. Outcomes of the questionnaires at 3 and 12 months were compared. RESULTS: Sixty patients were enrolled in the study. There were 30 in the conventional laparoscopic group (13 males; median age 69.3 years [range 35-80 years]) and 30 in the TaTME group (14 males; median age 75.6 years [range 42-83 years]). Three months after ileostmy closure, patients in the TaTME group had significantly more buttock pain (p = 0.030), bloating (p = 0.023), stool frequency (p = 0.013), flatulence (p < 0.001) and fecal incontinence (p = 0.044), although none of these differences persisted at 12 months. Patients in the TaTME group had a higher median overall LARS score at 3 months (p = 0.032) but there was no difference at 12 months. At 12 months after TaTME female patients had better women's sexual interest (p = 0.039) and dyspareunia scores (p < 0.001), while male patients had better erectile function (p = 0.038). Other scales did not reveal a significant difference at either 3 of 12 months between groups. CONCLUSIONS: Compared with patients with mid and low rectal cancer treated with conventional laparoscopic TME, those treated with TaTME have worse HRQoL and bowel function for a short period after primary resection, but seem to have better sexual function in the long term.

Survival outcomes after isolated local recurrence of rectal cancer and risk analysis affecting its resectability.

BACKGROUND AND OBJECTIVES: This study aimed to investigate the clinical course and prognostic factors after isolated local recurrence (iLR) and to identify the predictive factors for R0 resection of locally recurrent rectal cancer (LRRC). METHODS: We retrospectively reviewed the medical records of 76 patients with iLR who had undergone radical surgery for a primary tumor from 2003 to 2015. RESULTS: The iLR rate was 2.5%. From 76 patients, 39 patients underwent R0 resection for iLR. Multivariate analysis revealed that initial open surgery, neoadjuvant chemoradiation, and p/ypT ≥ 3 were poor prognostic factors after iLR as regard to the variables related to the primary tumor; and symptom presence at the time of iLR diagnosis, higher fixity, and no chemotherapy after iLR were associated with shorter overall survival after iLR, and R0 resection of LRRC was the only favorable prognostic factor for progression-free survival after iLR as regard to the variables related to LRRC. Higher tumor level, negative pathologic circumferential margin of the primary tumor, and low fixity of LRRC were favorable factors in achieving R0 resection of LRRC. CONCLUSIONS: Early detection of iLR before symptom development, use of chemotherapy after iLR and R0 resection of LRRC should be considered to improve survival outcomes after iLR.

Determining whether postoperative chemoradiotherapy is required in patients with pathologic T3N0 rectal cancer with negative resection margin.

PURPOSE: This study aimed to identify the risk factors for locoregional recurrence (LR) and determine possible candidates for postoperative concurrent chemoradiotherapy (CCRT) in pathologic T3N0 (pT3N0) rectal cancer patients with a negative resection margin after total mesorectal excision (TME). METHOD: Data from 365 patients who had pT3N0 rectal cancer between 2003 and 2012 in the Samsung Medical Center were reviewed. All patients underwent upfront surgery without preoperative treatment. Postoperative management involved either no adjuvant therapy (n = 122), chemotherapy alone (n = 100), or CCRT (n = 143). RESULTS: The median follow-up duration was 71 months. The 5-year overall survival, disease-free survival, and LR-free survival (LRFS) rates were 95.9%, 86.9%, and 96.3%, respectively. When comparing the three groups (surgery alone [n = 122], chemotherapy alone [n = 100], and CCRT [n = 143]), there was no significant difference in LRFS among them (94.0%, 93.4%, and 99.2%, respectively; p = 0.20). However, when patients were stratified by risk factors (distance from anal verge ≤ 5 cm and distal resection margin [DRM] ≤ 2 cm), the 5-year LRFS improved by more than 10% by adding CCRT (98.9% with CCRT vs. 87.4% without CCRT, p = 0.006) in those with more than one risk factor. Postoperative CCRT did not affect the 5-year LRFS (100% with CCRT vs. 99.0% without CCRT, p = 0.66) in patients with no risk factors. CONCLUSION: Postoperative CCRT significantly decreased LR in patients with pT3N0 rectal cancer with a negative resection margin but having a distance from the anal verge ≤ 5 cm or DRM ≤ 2 cm.