Rectal Cancer Research Articles

MR staging of rectal cancer: Comparison between the 2012 and 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guidelines

PurposeTo compare the adherence of the interpretation and reporting staging system, respectively proposed in the 2012 and 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guidelines for Magnetic Resonance Imaging (MRI) staging of rectal cancer, focusing on the improvement offered by the criteria introduced by 2016 ESGAR guidelines. MethodFifty-six patients affected by rectal cancer were included; 25/56 patients underwent upfront surgery; 31 underwent to neo-adjuvant chemo-radiotherapy before surgery. All patients underwent 3 T MRI examination for local staging. All MR exams were evaluated by two radiologists with 20- and 4-years’ experience, who were blinded to each other; the T and N stages, the Mesorectal Fascia (MRF) status and the Extramural Vascular Invasion (EMVI) were assessed according to both 2012 and 2016 ESGAR guidelines. The correlation between radiological and pathological findings, as well as the MRI staging were evaluated. ResultsAs to the expert reviewer, no significant differences were found by comparing the MR T and N stages, T and N restaging, MRF status and EMVI according to 2012 and 2016 ESGAR guidelines. As to the 4-years’ experience radiologist the MR staging agreement between 2012 and 2016 guidelines was “moderate” in N-stage evaluation and “fair” in T-restaging evaluation. No significant discrepancies were found for other parameters. ConclusionsMRI is a reliable method in rectal cancer staging/restaging. The assessment of T-restaging is improved by adopting the 2016 ESGAR guidelines, especially for non-expert readers; this result could be justified by the introduction of diffusion-weighted imaging. On the contrary, the newest guidelines do not improve the diagnostic performance in assessing nodal staging and restaging.

MRI-based radiomics for stratifying recurrence risk of early-onset rectal cancer: a multicenter study

Early-onset rectal cancer (EORC) is characterized by a unique disease process with different clinicopathological features compared with late-onset rectal cancer (LORC). Research on the risk of recurrence in EORC patients, however, is limited. We aim to develop a predictive model to accurately predict EORC recurrence risk. Rectal cancer patients who underwent radical surgery and T2-weighted imaging and diffusion-weighted imaging magnetic resonance imaging (MRI) were retrospectively enrolled from three medical institutions from November 2012 to November 2018. Differences in clinicopathological characteristics between EORC and LORC were compared. Five prediction models for disease-free survival were constructed based on clinicopathological variables and five radiomic features from pretreatment MRI of the EORC. A fixed cut-off value calculated in the training set was used to stratify EORC patients into high-risk and low-risk groups of post-operative recurrence. Model performance was evaluated by concordance index (C-index) and receiver operating characteristic curve. A total of 264 EORC patients (median age, 43 years, 163 males) and 778 LORC patients (median age, 62 years, 520 males) were enrolled. Pretreatment positive carcinoembryonic antigen [hazard ratio (HR)= 2.84, P= 0.006], pathological positive lymph node status (pN positive) [HR= 2.86, P= 0.011] and MRI-based radiomics score [HR= 2.72, P < 0.001] are independent risk factors for disease-free survival in EORC patients. The EORC-ClinPathRadiom model, constructed by integrating the clinicopathological characteristics and MRI-based radiomics features of EORC, showed C-index of 0.82, 0.82, and 0.81 in the training, internal, and external test sets, respectively. This model effectively stratified EORC patients into high risk and low risk of recurrence (HRs for the training, internal, and external test sets were 8.96, 6.81, and 7.46, respectively). The EORC-ClinPathRadiom model can effectively predict and stratify the risk of post-operative recurrence in EORC patients.

Magnetic resonance imaging-based radiomics in predicting the expression of Ki-67, p53, and epidermal growth factor receptor in rectal cancer

Magnetic resonance imaging-based radiomics in predicting the expression of Ki-67, p53, and epidermal growth factor receptor in rectal cancer

[Prognostic and Predictive Value of a Modified Diagnostic Biopsy-Adapted Immunoscore in Patients with Rectal Cancer After Neoadjuvant Treatment- a translational study from the STELLAR trial]

BackgroundThe purpose of this study was to assess the prognostic significance of the modified diagnostic biopsy-adapted immunoscore (mISb) in determining the outcomes for patients with locally advanced rectal cancer (LARC) in a neoadjuvant setting. MethodsWe included 181 LARC patients from a single subcenter of a prospective study comparing total neoadjuvant therapy (TNT) based on short-course radiotherapy with long-term chemoradiotherapy (CRT). Tumor biopsies at baseline were stained for CD8+ and CD3+ T-cell densities. The mISb was developed using mean percentile of CD8+ T-cell density and CD8/CD3 ratios. Patients were classified into low (0%-25%), intermediate (>25%-70%), and high (>70%-100%) in both groups. The relativity among different lymphocytes and their correlation with survival were illustrated. Survival analyses and Cox regression models were used to compare the prognostic value of mISb and ISb for survival outcomes, and to assess the role of mISb in TNT and CRT subgroups respectively. ResultsIn this study, 151 (83.4%) patients received surgery and 30 (16.6%) followed a watch and wait strategy. A strong correlation was found between CD8+ and CD3+ T-cell densities (R=0.86, P<0.001), while a weak correlation witnessed between CD8+ and CD8/CD3 ratio (R=0.45). The 3-year disease-free survival (DFS) for the entire cohort was 69.9%, with 57.2%, 68.6%, and 85.5% for the low, intermediate, and high mISb groups respectively (P=0.01), while ISb failed to distinguish survival outcomes. Multivariate analysis revealed mISb to be an independent prognostic factor for DFS in surgically treated patients (P=0.01). Specifically, patients with high mISb score showed longer PFS than other subgroups in the TNT cohort (P=0.049), but no significant difference was found in the CRT population. ConclusionsIn this study, mISb demonstrates significant prognostic value in LARC patients receiving preoperative therapies, especially in the TNT subgroup. These findings may help tailor the intensity of neoadjuvant therapy for patients.

CDX2-Suppressed Colorectal Cancers Possess Potentially Targetable Alterations in Receptor Tyrosine Kinases and Other Colorectal-Cancer-Associated Pathways.

Colorectal cancer, a prevalent gastrointestinal carcinoma, has a high risk for recurrence when locally advanced and remains lethal when in an advanced stage. Prognostic biomarkers may help in better delineating the aggressiveness of this disease in individual patients and help to tailor appropriate therapies. CDX2, a transcription factor of gastrointestinal differentiation, has been proposed as a biomarker for good outcomes and could also be a marker of specific sub-types amenable to targeted therapies. Colorectal cancers from The Cancer Genome Atlas (TCGA) colorectal cohort and colon cancers from the Sidra-LUMC AC-ICAM cohort were categorized according to their expressions of CDX2 mRNA. Groups with CDX2 suppression were compared with cancers showing no suppression regarding their clinical and genomic characteristics. CDX2-suppressed colorectal cancers showed a high prevalence of Microsatellite Instability (MSI) and a lower prevalence of chromosomal Instability (CIN) compared to non-CDX2-suppressed cancers. In addition, CDX2-suppressed cancers had a higher prevalence of mutations in several receptor tyrosine kinase genes, including EGFR, ERBB3, ERBB4, RET, and ROS1. In contrast, CDX2-suppressed cancers displayed lower mutation frequencies than non-CDX2-suppressed cancers in the genes encoding for the two most frequently mutated tumor suppressors, APC and TP53, and the most frequently mutated colorectal cancer oncogene, KRAS. However, CDX2-suppressed colorectal cancers had a higher prevalence of mutations in alternative genes of the WNT/APC/β-catenin and KRAS/BRAF/MEK pathways. In addition, they showed frequent mutations in DNA damage response (DDR) genes, such as BRCA2 and ATM. CDX2-suppressed colorectal cancers constitute a genomically distinct subset of colon and rectal cancers that have a lower prevalence of KRAS, APC, and TP53 mutations, but a high prevalence of mutations in less commonly mutated colorectal cancer genes. These alterations could serve as targets for personalized therapeutics in this subset.

124 - Deep Learning Reconstructed Reduced Field-of-View Diffusion Weighted Imaging in Rectal Cancer: Comparison of Image Quality

124 - Deep Learning Reconstructed Reduced Field-of-View Diffusion Weighted Imaging in Rectal Cancer: Comparison of Image Quality

Artificial Intelligence Hybrid Survival Assessment System for Robot-Assisted Proctectomy: A Retrospective Cohort Study.

Robotic-assisted proctectomy (RAP) has emerged as the predominant surgical approach for patients with rectal cancer in recent years; although good postoperative patient recovery with accurate prediction is a guarantee of adaptive surveillance management, there is still a lack of easy-to-use prognostic tools and risk scores designed specifically for those patients undergoing RAP. This study used the electronic health records of 506 RAP participants, including a National Specialist Center for da Vinci Robotic Colorectal Surgery (NSCVRCS) meta cohort, and an independent external validation Sun Yat-sen Memorial Hospital cohort. In the NSCVRCS meta cohort, patients were divided into a discovery cohort (70%, n = 268), where the best-fit model was applied to model our prediction system, RAP-AIscore. Subsequently, an internal validation process for RAP-AIscore was conducted using a replication cohort (30%, n = 116). The study designed and implemented a large-scale artificial intelligence (AI) hybrid framework to identify the best strategy for building a survival assessment system, the RAP-AIscore, from 132 potential modeling scenarios through a combination of iterative cross-validation, Monte Carlo cross-validation, and bootstrap resampling. The 10 variables most relevant to clinical interpretability were identified on the basis of the AI hybrid optimal model values, which helps provide reliable prognostic survival guidance for new patients. The consistent evaluation of discrimination, calibration, generalization, and prognostic value across cohorts reaffirmed the accuracy and robust extrapolation capability of this system. The 10 feature variables most associated with clinical interpretability on the basis of Shapley values were identified, facilitating reliable prognostic survival guidance for new patients. This study introduces a promising and informative tool, the RAP-AIscore, which can be explained through nomograms for interpreting clinical outcomes. It facilitates postoperative risk stratification management and enhances clinical management of prognosis for RAP patients.

The influence of pelvic bone dose-volume parameters on bone marrow suppression during radiotherapy in stage I-III rectal cancer patients based on real world data

BackgroundThe aim of this study was to evaluate the impact of pelvic bone dose-volume parameters on bone marrow suppression during radiotherapy (RT) in rectal cancer patients with stage I-III disease receiving either neoadjuvant radiotherapy (neo-RT) or curative-intent radiotherapy (cur-RT). Materials and methodsThis was a retrospective study with data mined from an electronic medical record review at a single institution. Between January 2016 and September 2022, rectal cancer patients who consecutively received neo-RT or cur-RT in our department were included. The data collected included complete baseline peripheral blood counts and hematological toxicity (HT) data collected during RT. The radiation dose-volume parameters of three pelvic bone marrow (PBM) subsites [iliac bone marrow (IBM), lumbosacral bone marrow (LSBM), and lower pelvis bone marrow (LPBM)] were collected. The primary endpoint was grade ≥ 2 HT (HT2+), including leukopenia, neutropenia, anemia, thrombocytopenia and total HTs. Logistic regression was employed to analyze the associations of HT2+ with dosimetric parameters and clinicopathologic characteristics. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were generated to verify the prediction efficacy of the pelvic bone dose-volume parameters combined with clinicopathologic indices. ResultsA total of 130 patients with stage I-III rectal cancer with complete clinical data were included. During neo-RT and cur-RT, 57 (43.8%) of these patients experienced HT2+. Multivariate analysis revealed that gender, the IBM-Dmean, the IBM-V15 and the IBM-V40 were significantly associated with Grade 2+ leukopenia (P < 0.05), and the AUC of gender combined with the IBM-Dmean, the IBM-V15 and the IBM-V40 in predicting Grade 2+ leukopenia was 0.834. The optimal cutoff values were an IBM-Dmean = 2692.75 cGy, an IBM-V15 = 86.65%, and an IBM-V40 = 20.75%. Patients who received oxaliplatin-containing concurrent chemotherapy (ChT) regimens were more likely to experience Grade 2+ thrombocytopenia (P=0.054). The AUC of concurrent ChT regimens in predicting Grade 2+ thrombocytopenia was 0.678. Female gender was significantly associated with Grade 2+ anemia and total HT2+ status. ConclusionAmong rectal cancer patients with stage I-III disease who received neo-RT or cur-RT, female patients with higher IBM-Dmean, IBM-V15 and IBM-V40 were more likely to experience Grade 2+ leukopenia, and oxaliplatin-containing concurrent ChT regimens were identified as a potential factor for increasing the incidence of Grade 2+ thrombocytopenia.

P49-2 Feasibility and safety of exercise in rectal cancer during chemoradiation: a systematic review

P49-2 Feasibility and safety of exercise in rectal cancer during chemoradiation: a systematic review

Neoadjuvant treatment with regorafenib and capecitabine combined with radiotherapy in locally advanced rectal cancer: a multicenter phase Ib trial (RECAP)–SAKK 41/16

BackgroundThe multi tyrosine kinase inhibitor regorafenib is active in metastatic colorectal cancer. Improvement in clinical outcome by adding regorafenib to long-course chemoradiotherapy (LcCRT) was investigated in molecularly undefined LARC. MethodsPatients with T3–4 and/or N+ but M0 rectal cancer were included. Neoadjuvant LcRCT consisted in capecitabine (C) 825mg/m2 d1–d38 and 28 fractions of 1.8Gy (50.4Gy). Regorafenib was added d1–14 and d22–35 in three dose escalation (DE) cohorts (40mg/80mg/120mg). The recommended dose (RD) was used for the expansion (EXP) cohort. Primary endpoints were dose-limiting toxicity (DLT) for DE and pathological response (near-complete regression [npCR] or complete regression [pCR]) for EXP. ResultsOverall, 25 patients were included. Two DLTs occurred at the regorafenib dose level of 120 mg, thereby establishing the RD at 80mg daily. Among the 19 patients who were treated at the RD, eight (42.1%; one-sided 80% confidence interval [CI] (lower bound): 30.7%; 95% CI: 20.3%–66.5%) reached the primary endpoint (five [26.3%] had npCR and three [15.8%] pCR). One additional patient received no surgery due to clinical complete response. All patients had R0 resections and clear circumferential margins. Postoperative complications occurred in six patients (35.3%). The most common grade ≥3 treatment-related adverse event in the EXP cohort was diarrhea (two patients). ConclusionAdding regorafenib 80mg to LcCRT in LARC resulted in both primary endpoints being met and yielded an expectedpathological response rate. Toxicity was manageable, and postoperative complications were as expected. Micro AbstractThe SAKK 41/16 study investigated the addition of regorafenib to the standard neoadjvuant chemoradiation with capecitabine. We could show expected pathological response rate and manageable toxicity at the recommended dose of regorafenib. Regorafenib may be potential partner for future trials investigating treatment intensification for high-risk locally advanced rectal cancer.

Visualization analysis of research hotspots and trends in MRI-based artificial intelligence in rectal cancer

BackgroundRectal cancer (RC) is one of the most common types of cancer worldwide. With the development of artificial intelligence (AI), the application of AI in preoperative evaluation and follow-up treatment of RC based on magnetic resonance imaging (MRI) has been the focus of research in this field. This review was conducted to develop comprehensive insight into the current research progress, hotspots, and future trends in AI based on MRI in RC, which remains to be studied. MethodsLiterature related to AI based on MRI and RC, as of November 2023, was obtained from the Web of Science Core Collection database. Visualization and bibliometric analyses of publication quantity and content were conducted to explore temporal trends, spatial distribution, collaborative networks, influential articles, keyword co-occurrence, and research directions. ResultsA total of 177 papers (152 original articles and 25 reviews) were identified from 24 countries/regions, 351 institutions, and 81 journals. Since 2019, the number of studies on this topic has rapidly increased. China and the United States have contributed the highest number of publications and institutions, cultivating the most intimate collaborative relationship. The highest number of articles derive from Sun Yat-sen University, while Frontiers in Oncology has published the highest number of relevant articles. Research on MRI-based AI in this field has mainly focused on preoperative diagnosis and prediction of treatment efficacy and prognosis. ConclusionsThis study provides an objective and comprehensive overview of the publications on MRI-based AI in RC and identifies the present research landscape, hotspots, and prospective trends in this field, which can provide valuable guidance for scholars worldwide.

Prediction of Kirsten rat sarcoma (KRAS) mutation in rectal cancer with amide proton transfer-weighted magnetic resonance imaging.

Kirsten rat sarcoma (KRAS) mutation drives resistance to anti-epidermal growth factor receptor (anti-EGFR)-targeted therapies in rectal cancer. Amide proton transfer-weighted magnetic resonance imaging (APTw MRI) might be a supplement to the evaluation of KRAS mutation because the APTw value can reflect mobile cellular protein content in vivo. This study aimed to determine whether APTw MRI could predict KRAS mutation in rectal cancer and compare this technique with diffusion-weighted imaging (DWI). This retrospective study reviewed 153 consecutive patients with rectal cancer from April 2019 to June 2021 in our hospital. Among them, a total of 55 patients who did not undergo neoadjuvant chemoradiotherapy and underwent preoperative APTw MRI, DWI, and postoperative KRAS tests were included in this study. In two-dimensional APTw images, two radiologists manually delineated three regions of interest (ROIs) along tumor contour in the largest slice and the adjacent two slices of tumor respectively. The mean APTw value within a ROI was calculated, and the values of three ROIs were averaged for each patient. In consecutive DWI images, two radiologists depicted the ROIs of the whole lesion, and the mean apparent diffusion coefficient (ADC) was generated. The intraclass correlation coefficient (ICC), Shapiro-Wilk test and Student's t-test were used for statistical analyses. Receiver operating characteristic (ROC) curves were constructed for APTw and ADC values respectively, and the area under the curve (AUC) was used to evaluate the diagnostic performance for the prediction of KRAS mutation. Among these 55 patients, KRAS mutation occurred in 21 patients. The ICCs of two independent raters for APTw and ADC values were 0.937 [95% confidence interval (CI), 0.914-0.953] and 0.976 (95% CI, 0.959-0.986), respectively. ADC values did not show a statistically significant difference between the KRAS-mutant group and the wild type (WT) group (P=0.733). KRAS-mutant tumors exhibited a higher APTw value than WT tumors in patients with rectal non-mucinous adenocarcinoma (3.324%±0.685% vs. 2.230%±0.833%, P<0.001). The AUC of the APTw value was 0.827 (95% CI, 0.701-0.916), with a cutoff value of 2.4% (sensitivity, 95.2%; specificity, 55.9%). DWI cannot differentiate mutant KRAS genes from WT genes in patients with rectal cancer, but APTw MRI has potential for evaluating KRAS mutation in rectal cancer. The APTw value had moderate diagnostic performance in the prediction of KRAS mutation with a high sensitivity but a low specificity. APTw MRI might be a promising supplement to KRAS genomic analysis in rectal cancer patients.

S2923 Unmasking the Mimic: Rectal Endometriosis Deceptive Presentation as Rectal Cancer

S2923 Unmasking the Mimic: Rectal Endometriosis Deceptive Presentation as Rectal Cancer

Efficient application of deep learning-based elective lymph node regions delineation for pelvic malignancies.

While there are established international consensuses on the delineation of pelvic lymph node regions (LNRs), significant inter- and intra-observer variabilities persist. Contouring these clinical target volumes for irradiation in pelvic malignancies is both time-consuming and labor-intensive. The purpose of this study was to develop a deep learning model of pelvic LNRs delineation for patients with pelvic cancers. Planning computed tomography (CT) studies of 160 patients with pelvic primary malignancies (including rectal, prostate, and cervical cancer) were retrospectively collected and divided into training set (n=120) and testing set (n=40). Six pelvic LNRs, including abdominal presacral, pelvic presacral, internal iliac nodes, external iliac nodes, obturator nodes, and inguinal nodes were delineated by two radiation oncologists as ground truth (Gt) contours. The cascaded multi-heads U-net (CMU-net) was constructed based on the Gt contours from training cohort, which was subsequently verified in the testing cohort. The automatic delineation of six LNRs (Auto) was evaluated using dice similarity coefficient (DSC), average surface distance (ASD), 95th percentile Hausdorff distance (HD95), and a 7-point scale score. In the testing set, the DSC of six pelvic LNRs by CMU-net model varied from 0.851 to 0.942, ASD from 0.381 to 1.037mm, and HD95 from 2.025 to 3.697mm. No significant differences were founded in these three parameters between postoperative and preoperative cases. 95.9% and 96.2% of auto delineations by CMU-net model got a score of 1-3 by two expert radiation oncologists, respectively, meaning only minor edits needed. The CMU-net was successfully developed for automated delineation of pelvic LNRs for pelvic malignancies radiotherapy with improved contouring efficiency and highly consistent, which might justify its implementation in radiotherapy work flow.

Exercise During Neoadjuvant Chemoradiation Treatment To Improve Rectal And Esophageal Cancer Outcome (EXENTRO) Pilot Trial

Exercise During Neoadjuvant Chemoradiation Treatment To Improve Rectal And Esophageal Cancer Outcome (EXENTRO) Pilot Trial

Impacts of metastatic colorectal cancer (mCRC) on patient health-related quality of life (HRQoL): Results of an online US patient survey.

242 Background: Effects of disease symptoms and treatment negatively impact the HRQoL of patients (pts) with mCRC, including physical and psychological well-being. Understanding challenges faced by pts with mCRC may help improve HRQoL and enhance their disease journey. Using an online survey, we aimed to gain insights into the effects of mCRC on HRQoL. Methods: Pts aged ≥18 yrs with stage IV colon, rectal, or colorectal cancer participated in an online survey conducted in the US by The Harris Poll between 01/17/24-02/07/24. Of the 344 pts who participated, 254 were recruited via online panels and 90 via pt advocacy groups (PAGs; BLKHLTH, COLONTOWN, Colorectal Cancer Alliance, and Family Reach). The 60-question survey explored the pt profile, diagnosis experience, the role of PAGs/other resources, HRQoL, access to care and financial challenges, discrimination, and treatment experience. Raw data were not weighted and thus are only representative of participants who completed the survey. Sample data are accurate to within 5.3 %-points using a 95% confidence level; all surveys are subject to multiple sources of error. Results: Of 344 participants, 190 (55%) were male, mean age was 56 yrs (±13 yrs); the majority were White (n=158 46%), Black/African American (n=87 25%), or Hispanic (n=75 22%). Of applicable respondents, a majority reported that mCRC had a negative impact on maintaining a normal work schedule (69%), financial wellbeing (69%), emotional wellbeing (67%), hobbies (64%), physical activity (63%), and romantic relationships (61%). However, 43% of applicable pts reported a positive impact on relationships with family and friends, while 70% of overall respondents agreed that a diagnosis had inspired them to act on things they’ve always wanted to do or have pushed off. From an emotional perspective, most pts agreed that they felt like a burden to family (72%) or sensed decreasing support over time from family/friends (63%). Although for many pts a diagnosis had brought them closer to loved ones, 78% agreed they had at times felt alone in their experience, and 70% struggled with being emotionally present. Further, among 330 (96%) pts who had attempted to access mental health resources, 55% had found this difficult, especially Black pts compared to Hispanic and White pts (Table). Conclusions: During their disease journey, pts with mCRC suffer a deterioration in multiple aspects of HRQoL that affects their daily lives, including emotional/mental wellbeing. Better support, specifically improving ease of access to mental health resources, is needed to help pts maintain HRQoL throughout their disease journey. Ease of access to mental health resources for Black, Hispanic, and White pts. Ease of access, % All patients n=330 Black patients n=85 Hispanic patients n=75 White patients n=146 Very difficult 21 27 15 19 Somewhat difficult 35 36 24 39 Somewhat easy 26 16 41 25 Very easy 18 20 20 17

334 - The evolution of bowel symptoms after surgery for rectal cancer: a two-year follow-up

334 - The evolution of bowel symptoms after surgery for rectal cancer: a two-year follow-up

Oncological and functional outcomes of sphincter saving procedures versus abdominoperineal resection for low rectal cancer: A comparative prospective cohort study.

Oncological and functional outcomes of sphincter saving procedures versus abdominoperineal resection for low rectal cancer: A comparative prospective cohort study.

Characterization and proteomic analysis of plasma-derived small extracellular vesicles in locally advanced rectal cancer patients.

Neoadjuvant chemoradiotherapy (nCRT) stands as a pivotal therapeutic approach for locally advanced rectal cancer (LARC), yet the absence of a reliable biomarker to forecast its efficacy remains a challenge. Thus, this study aimed to assess whether the proteomic compositions of small extracellular vesicles (sEVs) might offer predictive insights into nCRT response among patients with LARC, while also delving into the proteomic alterations within sEVs post nCRT. Plasma samples were obtained from LARC patients both pre- and post-nCRT. Plasma-derived sEVs were isolated utilizing the TIO2-based method, followed by LC-MS/MS-based proteomic analysis. Subsequently, pathway enrichment analysis was performed to the Differentially Expressed Proteins (DEPs). Additionally, ROC curves were generated to evaluate the predictive potential of sEV proteins in determining nCRT response. Public databases were interrogated to identify sEV protein-associated genes that are correlated with the response to nCRT in LARC. A total of 16 patients were enrolled. Among them, 8 patients achieved a pathological complete response (good responders, GR), while the remaining 8 did not achieve a complete response (poor responders, PR). Our analysis of pretreatment plasma-derived sEVs revealed 67 significantly up-regulated DEPs and 9 significantly down-regulated DEPs. Notably, PROC (AUC: 0.922), F7 (AUC: 0.953) and AZU1 (AUC: 0.906) demonstrated high AUC values and significant differences (P value < 0.05) in discriminating between GR and PR patients. Furthermore, a signature consisting of 5 sEV protein-associated genes (S100A6, ENO1, MIF, PRDX6 and MYL6) was capable of predicting the response to nCRT, yielding an AUC of 0.621(95% CI: 0.454-0.788). Besides, this 5-sEV protein-associated gene signature enabled stratification of patients into low- and high-risk group, with the low-risk group demonstrating a longer overall survival in the testing set (P = 0.048). Moreover, our investigation identified 11 significantly up-regulated DEPs and 31 significantly down-regulated DEPs when comparing pre- and post-nCRT proteomic profiles. GO analysis unveiled enrichment in the regulation of phospholipase A2 activity. Differential expression of sEV proteins distinguishes between GR and PR patients and holds promise as predictive markers for nCRT response and prognosis in patients with LARC. Furthermore, our findings highlight substantial alterations in sEV protein composition following nCRT.

Laparoscopic colectomy for patients with poor American Society of Anesthesiology classifications.

The American Society of Anesthesiologists (ASA) classification is used to assess the fitness of a patient for surgery. Whether laparoscopic surgery is appropriate for colorectal cancer patients with poor ASA performance status (PS) remains unclear. Among 4585 patients who underwent colorectal surgery between 2016 and 2023, this study retrospectively reviewed all 458 patients with ASA-PS ≥3. Patients were divided into two groups: patients treated by open surgery (O group, n = 80); and patients treated by laparoscopic surgery (L group, n = 378). We investigated the impact of surgical approach on postoperative complications in patients with colorectal cancer and ASA-PS ≥3. Operation time was longer (170 min vs. 233 min, p < .001), blood loss was less (156 mL vs. 23 mL, p < .001), postoperative complications were less frequent (40.0% vs. 25.1%, p = .008), and hospital stay was shorter (23 days vs. 14 days, p < .001) in L group. Univariate analysis revealed rectal cancer, open surgery, longer operation time, and blood loss as factors significantly associated with postoperative complications. Multivariate analysis revealed open surgery (odds ratio [OR] 2.100, 95% confidence interval [CI] 1.164-3.788; p = .013) and longer operation time (OR 1.747, 95% CI 1.098-2.778; p = .018) as independent predictors of postoperative complications. Laparoscopic surgery provides favorable outcomes for colorectal cancer patients with poor ASA-PS.