To investigate the clinical efficacy of neoadjuvant imatinib in the treatment of rectal gastrointestinal stromal tumor (GIST).

This study explored how the human cortical folding pattern composed of convex gyri and concave sulci affected single-subject morphological brain networks, which are becoming an important method for studying the human brain connectome. We found that gyri-gyri networks exhibited higher morphological similarity, lower small-world parameters, and lower long-term test-retest reliability than sulci-sulci networks for cortical thickness- and gyrification index-based networks, while opposite patterns were observed for fractal dimension-based networks. Further behavioral association analysis revealed that gyri-gyri networks and connections between gyral and sulcal regions significantly explained inter-individual variance in Cognition and Motor domains for fractal dimension- and sulcal depth-based networks. Finally, the clinical application showed that only sulci-sulci networks exhibited morphological similarity reductions in major depressive disorder for cortical thickness-, fractal dimension-, and gyrification index-based networks. Taken together, these findings provide novel insights into the constraint of the cortical folding pattern to the network organization of the human brain.
Humans ; Cerebral Cortex/anatomy & histology* ; Male ; Female ; Magnetic Resonance Imaging ; Adult ; Connectome/methods* ; Young Adult ; Nerve Net/anatomy & histology* ; Neural Pathways ; Depressive Disorder, Major/diagnostic imaging*

The integration of immunotherapy into neoadjuvant treatment for locally advanced rectal cancer has markedly increased complete response rates, offering greater potential for organ preservation. However, the reduced restaging accuracy after immunotherapy has limited the applicability of the watch-and-wait strategy. As an organ-preserving approach that enables residual lesion removal and pathological assessment, local excision not only reduces the risk of local regrowth associated with watch-and-wait, but also enables full-thickness tumor bed sampling to determine pathological stage, regression pattern, and molecular characteristics, thereby supporting risk stratification and individualized decision-making. Moving forward, local excision is expected to achieve precise, risk-adapted organ preservation by optimizing surgical timing and techniques, and integrating multimodal parameters including imaging, pathology, and the tumor microenvironment, ultimately attaining the dual aim of maximizing both oncologic efficacy and functional preservation.

Anastomotic leakage is a common complication in laparoscopic rectal cancer surgery, which can significantly impact patient recovery. This issue becomes even more critical in the context of the widespread application of standardized and procedural neoadjuvant patterns, as well as the increasing feasibility of anal-preserving surgery for ultra-low rectal cancer. Therefore, strategies to reduce or prevent anastomotic leakage are of paramount importance. Anastomotic tension and blood supply are two key factors that contribute to the success of anastomosis. In laparoscopic rectal cancer surgery, minimizing anastomotic tension and optimizing blood supply are essential to preventing or mitigating the occurrence of anastomotic leakage. This article would discuss the risk factors, preventive measures, and treatment approaches for postoperative anastomotic leakage in rectal cancer surgery.

Objective:To compare the impact of different treatment strategies on the survival outcomes in rectal cancer patients with poor response to neoadjuvant therapy, and to explore the survival-related influencing factors.Methods:A retrospective cohort study was conducted. Between January 2018 and November 2022, the clinical, pathological, and follow-up data of 106 rectal cancer patients who received neoadjuvant therapy and were evaluated as grade 4 or 5 based on the Magnetic Resonance Tumor Regression Grade (mrTRG) from the rectal cancer database at Peking Union Medical College Hospital were retrospectively collected. Based on the post-neoadjuvant therapy assessment, patients were classified into three groups: the chemotherapy-radiotherapy group (23 patients), the consolidation therapy group (18 patients), and the standard treatment group (65 patients). General condition, pathological findings, selection of neoadjuvant therapy, comorbidities, as well as 3-year expected DMFS and OS were observed in the three groups.Results:All 106 patients were followed up, with a median follow-up time of 28 (21, 38) months. The overall 3-year DMFS rate was 60%, and the 3-year OS rate was 74%. The 3-year DMFS in the standard treatment and consolidation therapy groups were 74% and 72%, respectively; the 3-year OS were 84%, 81%, respectively. The Log-rank test showed that there was no significant difference in the 3-year expected DMFS and OS between the standard treatment group and the consolidation therapy group (both P>0.05), but both groups had better survival outcomes than the chemotherapy-radiotherapy group (10% and 39%, respectively; all P<0.001). Multivariate Cox regression analysis indicated that the chemotherapy-radiotherapy only regimen was an independent risk factor for DMFS (HR=12.425, 95% CI: 4.436–34.594, P<0.001), and the independent risk factors for OS were chemotherapy-radiotherapy only regimen (HR=8.991, 95%CI:2.220–36.403, P=0.002) and age≥65 years (HR=3.495, 95%CI: 1.017–12.009, P=0.047). Stratified analysis showed that chemotherapy-radiotherapy only regimen was the independent risk factors for DMFS and OS in patients with extramural vascular invasion (EMVI) positive ( n=66) and mesorectal fascial invasion (MRF) positive (n=56) (all P<0.05). Whether consolidation therapy was added to the standard neoadjuvant treatment regimen was not an independent factor affecting 3-year expected DMFS or OS in rectal cancer patients with poor response to neoadjuvant therapy. Further comparisons between the standard neoadjuvant treatment and consolidation therapy groups showed no statistically significant differences in spincter-preservation rate or postoperative complication rates (both P>0.05). However, the consolidation therapy group had a longer interval between the end of radiotherapy and surgery [80.1 (50.8, 109.4) days vs. 61.8 (48.8, 74.8) days, P<0.001], and a higher incidence of chemotherapy-related adverse effects ([10/18] vs. 26.2% [17/65], P=0.018). Conclusion:In rectal cancer patients with poor response to neoadjuvant therapy and clear adverse prognostic features before surgery (locally advanced stage, MRF positive or EMVI positive), the addition of short- or long-course chemotherapy-based systemic therapy does not provide short- or long-term survival benefits. Moreover, an extended chemotherapy duration increases the incidence of chemotherapy-related adverse effects.

Objective:To analyze the types and characteristics of post-operative complications in colorectal cancer patients aged over 85 years undergoing laparoscopic surgery, and to summarize peri-operative management strategies.Methods:This was an observational study. Inclusion criteria: pathologically confirmed adenocarcinoma; tumor located in ileocecum, ascending colon, transverse colon, descending colon, sigmoid colon, or rectum; undergoing laparoscopic radical resection for colorectal cancer; complete clinical data. Exclusion criteria included distant metastasis, synchronous resection of multiple primary cancers, simultaneous liver metastasis surgery, and follow-up duration <1 month. A retrospective analysis was conducted on 191 patients of colorectal cancer patients aged over 85 years who underwent laparoscopic radical surgery in the General Surgery Department at Peking Union Medical College Hospital from January 2019 to January 2024. Among 191 patients, 107 patients (56.0%) had colon cancer and 84 (44.0%) rectal cancer. All patients received "home-based prehabilitation" and post-operative "enhanced recovery after surgery" protocols. Patient characteristics, peri-operative complication types, treatments, and outcomes were analyzed.Results:Post-operative complications occurred in 97 patients (50.8%), including 53 colon cancer patients (54.6%) and 44 rectal cancer patients (45.4%). Comorbidities existed in 88 patients (90.7%), with 93 patients (95.9%) classified as ASA II-III pre-operatively and 86 (88.7%) having nutritional risks. Surgical procedures included Dixon procedure (38 patients, 39.2%), right hemicolectomy (33 patients, 34.0%), sigmoidectomy (10 patients, 10.3%), and 17 patients (17.5%) received prophylactic stomas. Complication types comprised non-anastomotic infections (38 patients, 19.9%), intestinal flora disorder (26 patients, 13.6%), anastomotic/wound/stoma-related complications (16 patients, 8.4%), thrombotic/hemorrhagic events (6 patients, 3.1%), and others (11 patients, 5.8%). By Clavien-Dindo classification: Grade I (12 patients, 6.3%), Grade II (69 patients, 36.1%), Grade III (12 patients, 6.3%), and Grade IV (4 patients, 2.1%). Except for 5 patients (2.6%) requiring unplanned re-operation, all complications resolved with conservative treatment. The median duration of post-operative hospitalization was 9.5 days (7–13).Conclusion:Non-anastomotic infections and intestinal flora disorder constitute predominant complications after laparoscopic surgery in colorectal cancer patients aged over 85 years, mostly manageable with conservative treatment. Strengthened peri-operative management incorporating pre-operative prehabilitation and post-operative enhanced recovery after surgery protocols is crucial for patients aged over 85 years.

Objective:To explore the application of the camera inversion technique in laparoscopic sphincter-preserving surgery for mid to low rectal cancer.Methods:A retrospective study with historical controls was conducted on patients with non-metastatic mid to low rectal cancer which received laparoscopic total mesorectal excision at Peking Union Medical College Hospital from January 2019 to June 2024. The experimental group (2021.7-2024.6) utilized the camera inversion technique (rotating the lens 180° to position the bevel upward and switching the system to reverse display mode for improved visualization and operative angles) during key surgical steps (such as intraoperative mobilization of the mid-to-lower rectum and anastomosis), while the control group (2019.1-2021.6) did not. Clinical data and surgical videos were collected to analyze indicators like operative time, blood loss, mesorectal integrity, surgical complications, and postoperative hospital stay.Results:A total of 624 patients with non-metastatic mid to low rectal cancer were included, including 412 males and 212 females, with an average age of 59.8 years and an average tumor distance of 5.6 cm from the anal verge. The experimental group comprised 301 patients, while the control group had 323 patients.The proportion of abdominal ISR (intersphincteric resection) was significantly higher in the experimental group [19.3% (58/301) vs. 10.2%(33/323), χ 2=10.140, P=0.001], with a reduction in operative time [(161.8±67.8) minutes vs. (150.2±68.5) minutes, t=2.134, P=0.033] and a decrease in postoperative hospital stay [(7.8±2.1) days vs. (8.3±3.4) days, t=2.003, P=0.046]. The experimental group also demonstrated advantages in intraoperative blood loss, mesorectal integrity rate, and postoperative complications such as urinary retention, though these differences were not statistically significant (all P>0.05). Conclusion:In laparoscopic surgery for mid to low rectal cancer, using camera inversion technique during distal rectum dissection and transanal anastomosis can provide better surgical field exposure, facilitate precise operations within the correct anatomical plane, and minimize collateral damage. The camera inversion technique is safe and effective.

Background and Aims:For patients with mid-to-low rectal cancer who achieve clinical complete response(cCR)or near-cCR after neoadjuvant chemoradiotherapy(nCRT),the key concern for both clinicians and patients is how to preserve anal function as much as possible without significantly compromising oncological outcomes.This study was performed to evaluate the safety and feasibility of local excision as an anus-preserving approach in rectal cancer patients with cCR or near-cCR.Methods:A retrospective analysis was conducted on 51 patients with mid-to-low rectal cancer who underwent local resection after achieving cCR or near-cCR following nCRT at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between March 2014 and July 2023.The clinical characteristics,imaging and pathological findings,surgical outcomes,as well as oncological and functional results were reviewed.Results:Among the 51 patients,34 were male and 17 were female,with a mean age of 61±14 years.Pre-nCRT imaging staging showed:cT1-2N0 in 12 cases(23.5％),cT3N0 in 13 cases(25.5％),cT1-3N0-1 in 19 cases(37.4％),and cT1-3N2 in 7 cases(13.7％).The average tumor distance from the anal verge was(4.5±1.1)cm.After achieving cCR or near-cCR following nCRT,all patients underwent local resection:40 cases(78.4％)underwent transanal endoscopic microsurgery(TEM),7 cases(13.7％)underwent transanal minimally invasive surgery(TAMIS),and 4 cases(7.8％)underwent conventional transanal local excision.The postoperative complication rate was 27.5％(14/51),with 71.4％classified as Clavien-Dindo grade Ⅰ.Postoperative histopathology showed ypT0 in 26 cases(51.0％),ypT1 in 8 cases(15.7％),ypT2 in 16 cases(31.4％),and ypT3 in 1 case(2.0％).The concordance rate between pathological results and preoperative imaging was 54.9％.Over a median follow-up of 60 months(range:34-79),there were 4 cases(7.8％)of local recurrence,12 cases(23.5％)of distant metastasis,and 5 cancer-related deaths(9.8％).Six months postoperatively,both the Wexner score and the low anterior resection syndrome(LARS)score significantly improved compared to post-nCRT values[Wexner:1(0-2)vs.2(1-5);LARS:3.3±5.75 vs.4.3±6.86;both P＜0.01].Conclusion:For patients with mid-to-low rectal cancer who achieve cCR or near-cCR after nCRT,local en bloc resection of the bowel wall lesions enables accurate assessment of residual tumor status and facilitates personalized subsequent treatment,potentially sparing some patients from radical surgery.Local resection can be a viable anus-preserving option for patients who are unfit for or strongly averse to radical resection.However,local excision cannot replace radical surgery,and its precise indications warrant further investigation.

Background and Purpose:Neoadjuvant immunotherapy currently significantly enhances treatment efficacy for locally advanced rectal cancer(LARC);However,clinical management of immune-related adverse events(irAEs)lacks robust evidence.This study aimed to investigate the characteristics,clinical management strategies,and outcomes of irAEs during neoadjuvant immunotherapy for rectal cancer,providing a basis for optimizing irAEs monitoring and intervention.Methods:We retrospectively analyzed clinical data from LARC patients who developed irAEs after receiving neoadjuvant immunotherapy at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between July 2022 and June 2024.Types of irAEs,severity,time of onset,management strategies,and outcomes were recorded.All patients underwent regular follow-up for at least 6 months.This study has been approved by Peking Union Medical College Hospital,Chinese Academy of Medical Sciences(ethical approval number:I-24PJ0024).Descriptive statistics were used to summarize irAEs patterns and management approaches.Results:A total of 41 irAE episodes occurred among the 30 patients.Mild irAEs(Grade 1-2)accounted for 78.0%(32/41),while severe irAEs(Grade 3-4)constituted 22.0%(9/41).Five patients(16.7%)permanently discontinued treatment due to severe toxicity.Endocrine toxicities were most frequent(36.6%,15/41),primarily characterized by progression from hyperthyroidism to hypothyroidism;75.0%required thyroid hormone replacement therapy.One case of delayed-onset adrenal insufficiency was alleviated with glucocorticoid(GC)therapy.Among hepatotoxicities(19.5%,8/41),62.5%were Grade 3 injury,and 37.5%required GC intervention;two patients experienced recurrence during adjuvant chemotherapy.Three cases of severe myositis occurred,accompanied by asymptomatic myocardial injury(evidenced by markedly elevated creatine kinase and concurrent changes in cardiac biomarkers),all requiring high-dose GC pulse therapy combined with intravenous immunoglobulin or immunosuppressants(recovery period:2-4 months).Nine dermatological reactions were managed with topical therapy.Two gastrointestinal events occurred,including one Grade 3 diarrhea treated with GCs.The overall GC usage rate was 31.7%(13/41),with 76.9%administered for Grade≥3 irAEs.Conclusion:irAEs during neoadjuvant immunotherapy for LARC are predominantly mild-to-moderate and manageable with supportive care.However,some patients develop severe(Grade 3-4)irAEs requiring multidisciplinary management.GC usage is concentrated in higher-grade irAEs,with severe myositis and cardiac involvement necessitating intensive immunosuppressive therapy despite their rarity.Recurrence of irAEs during adjuvant chemotherapy in a minority of patients underscores the necessity for early recognition,graded intervention,and comprehensive management throughout the entire treatment cycle.