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*

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.

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.

Objective:To compare the prognostic impact of complete mesocolic excision (CME) versus D2 lymphadenectomy in patients with stage III right-sided colon cancer.Methods:A retrospective cohort study was conducted. Clinical data of 263 patients with stage III colon cancer undergoing right hemicolectomy in the Division of Colorectal Surgery, Department of General Surgery, Peking Union Medical College Hospital (January 1, 2016 to August 8, 2023) were included. Of the 263 patients, 152 underwent CME and 111 received D2 dissection. Propensity score matching (PSM) was employed to balance baseline characteristics between the two groups. Continuous variables were compared using the Mann-Whitney U test or Student's t-test; categorical variables were compared using the χ2 test or Fisher exact test. Survival curves were constructed using the Kaplan-Meier method, and the Log-Rank test was used to compare disease-free survival (DFS) and overall survival (OS) between groups. Cox proportional hazards models were utilized to analyze prognostic factors, with subgroup analyses performed.Results:Patients undergoing CME surgery were younger (proportion >75 years: 4.6% vs. 25.2%, P<0.001), had a lower burden of comorbidities (Charlson comorbidity index ≥ 1: 25.0% vs. 36.9%, P=0.045), The rates of open surgery and converted open surgery were lower [0.6% (1/152) vs. 4.5% (5/111) and 0.6% (1/152) vs. 2.7% (3/111), respectively; P=0.040].They also had a higher rate of receiving adjuvant therapy (92.7% vs. 76.0%, P<0.001). In terms of short-term postoperative outcomes, the CME group had a greater number of harvested lymph nodes (median: 30 vs. 25, P<0.001) and less blood loss (median: 20 ml vs. 20 ml, P=0.041). There were no significant differences between the groups in terms of the number of metastatic lymph nodes, operation time, and the incidence of postoperative complications. Survival analysis demonstrated significantly longer DFS in the CME group both before and after PSM. CME was an independent favorable prognostic factor for DFS (pre-PSM: HR=0.53, 95%CI: 0.31-0.91, P=0.022; post-PSM: HR=0.50, 95%CI: 0.26-0.97, P=0.042). No significant difference in OS was detected between the two groups across models. The subgroup analysis based on clinicopathological features revealed DFS benefits associated with CME in patients with tumor deposits (HR=0.41, 95%CI: 0.18-0.94, P=0.035), moderately-to-well-differentiated adenocarcinoma(HR=0.48, 95%CI: 0.26-0.90, P=0.023), proficient mismatch repair tumors (HR=0.55, 95%CI: 0.32-0.94, P=0.030), and pN2 stage disease (HR=0.43, 95%CI: 0.19-0.95, P=0.036). Conclusion:An extended lymph node dissection, as exemplified by CME, may confer a DFS advantage in patients with stage III right-sided colon cancer, especially those exhibiting a substantial burden of lymph node metastases.

Objective:To investigate the complications, along with their diagnosis and management, that follow local excision for rectal cancer after neoadjuvant therapy.Methods:The clinical data of 53 patients with rectal cancer who underwent local resection after neoadjuvant treatment in Peking Union Medical College Hospital from January, 2010 to December, 2024 were retrospectively collected for this descriptive case series study. Indications for local resection were: (1) age ≥ 18 years; (2) American Society of Anesthesiologists (ASA) classification I-III; (3) pathologically confirmed rectal adenocarcinoma; (4) distance from the lower edge of the tumor to the anal edge of less than 8 cm; and (5) use of preoperative neoadjuvant therapy. Contraindications of local resection were: (1) multiple primary colorectal cancer and (2) intestinal obstruction, intestinal perforation, or and gastrointestinal bleeding that required emergency surgery. There were 36 males and 17 females, and the median age was 62 (26-85) years. After neoadjuvant therapy, the median distance from the tumor to the anal margin was 4.5 (range, 2.2-6.9) cm. The main outcome measures included: surgical details, pathological findings, postoperative complications, anorectal function, and oncological outcomes (recurrence and survival).Results:Surgical methods included transanal endoscopic microsurgery (TEM) in 47 cases, transanal minimally invasive surgery (TAMIS) in 3 cases, and traditional transanal local resection in 3 cases. Of the 53 patients, 29 (54.7%) had pathological complete response (pCR), namely pT0 stage; 8 cases were pT1, 15 cases were pT2, and 1 case was pT3. Twenty-four cases (45.3%) had 33 complications. Clavien-Dindo grade I-II accounted for 97.0% (32/33), including 14 cases (26.4%) of wound dehiscence. Low anterior resection syndrome (LARS) occurred in 7 cases (13.2%), including 5 minor cases and 2 major cases. Postoperative fever occurred in 7 cases (13.2%); urinary retention occurred in 3 cases (5.7%); and diarrhea occurred in 1 case (1.9%). Clavien Dindo grade III was observed in only 3.0% (1/33) of patients, which was a rectovaginal fistula. Among the 14 patients with wound dehiscence, 7 cases only suffered anal pain and were cured after symptomatic analgesic treatment. Five cases suffered anal pain with hematochezia but improved after treatment with essential diet, hemostasis, intravenous antibiotics, pain relief, and sitz bath. Two cases of secondary perianal infection were treated with intravenous antibiotics, local drainage, parenteral nutrition support, and symptomatic treatment, and the wounds healed within 2 months. One patient with rectovaginal fistula underwent transverse colostomy. After six months, the fistula healed and stoma reversal was performed. Seven patients with LARS received anal lifting exercise and defecation reflex training, and anal function recovered to the preoperative level after 1 year. Other complications improved after symptomatic treatment, pain relief, or catheter replacement. The median follow-up time was 60 months. Local recurrence occurred in 4 patients (7.5%) and distant metastasis occurred in 12 patients (22.6%). Seven patients (13.2%) died. The 5-year disease-free survival rate was 75.5%, and the 5-year overall survival rate was 86.8%.Conclusions:Local excision for rectal cancer following neoadjuvant therapy has a high incidence of complications, mainly wound-related, due to the decline of rectal wound healing ability after radiotherapy. However, most of the complications were relieved after symptomatic treatment, and the risk was controllable.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

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.

Objective:To evaluate the clinical features and risk factors of anastomotic leakage (AL) in patients with locally advanced rectal cancer (LARC) receiving neoadjuvant chemoradiotherapy (nCRT) followed by laparoscopic radical resection and proctocol ostomy.Method:Clinicla data of LARC patients receiving neoadjuvant chemoradiotherapy followed by laparoscopic radical resection and proctocol ostomy admitted to Peking Union Medical College Hospital between Jan 2019 and Oct 2023 was enrolled. According to the occurrence of AL, patients were divided into AL group and non-AL group.Results:After propersity matching score(PSM), there were 40 patients (33.4%) and 80 patients (66.6%) in the AL and non-AL group, respectively. The first-onset symptoms of AL were abnormal character and color of the drainage (23 cases, 57.5%) and fever (14 cases, 35.0%). About 82.5% of the AL were graded as B,and all 36 patients (90.0%) were managed consveratively by fully drainage anti-infection therapy. Logistic regression analysis indicated that tumor circumferential range more than 1/2 cycle ( OR=5.95, 95% CI:2.12-1.67, P=0.004), male ( OR=4.28, 95% CI:1.22-15.00, P=0.023) and high-ligation of Inferior mesenteric artery ( OR=8.08, 95% CI:1.86-37.78, P=0.006) were independent risk factors of AL. Conclusions:In this series, grade-B AL ranks the top of the incidence, and all were cured by conservative therapy. Special attention should be paid to those patients with the characteristics of male, tumor circumferential range more than 1/2 cycle, and high-ligation of inferior mesenteric artery.