ObjectiveTo explore the prevalence and adjacency of the tributaries of superior mesenteric vessel. MethodsThis study is a prospective study. The patients with right-sided colonic malignant tumor who underwent laparoscopic complete mesocolon excision at the Division of Colorectal Surgery of Peking Union Medical College Hospital from July 2016 to September 2022 were collected. The real-time observation and evaluation of vascular anatomy was performed by the operator and recorded by a resident. The continuous variables without a normal distribution were summarized as median (P25, P75). The categorical variables were presented as number (%). ResultsA total of 200 patients were enrolled, including 114 males and 86 females, with an age of 63.5 (53.5, 72.0) years. The prevalence of ileocolic artery and vein was 98.0% (196/200) and 98.5% (197/200), respectively. There were 168 (86.2%) cases of the ileocolic vein accompanied the course of the ileocolic artery at the origin in 195 patients with simultaneous presence of ileocolic artery and vein. The right colic artery and vein was present in 39.5% (79/200) and 18.5% (37/200) patients, respectively. The prevalence of the middle colic artery and vein was 96.5% (193/200) and 90.5% (181/200), respectively. And the prevalence of the middle colic vein accompanied the path of the middle colic artery at the root was 67.8% (118/174) in the 174 patients with simultaneous presence of middle colic artery and vein. The trunk length of the middle colic artery was 2.2 (1.6, 3.2) cm. The Henle trunk was present in 185 (92.5%) cases, with a trunk length of 1.00 (0.50, 1.40) cm, and its lower edge was 2.80 (2.20, 3.30) cm from the junction of the pancreatic head and the horizontal part of the duodenum.ConclusionsThe results from the data analysis of this study suggest that the ileocolic artery and vein are present most constantly with a high incidence of the ileocolic vein accompanied the course of the ileocolic artery at the origin of superior mesenteric vessels. Therefore ileocolic artery and vein are expected to serve as an optimal anatomical landmarks for the caudal-to-cranial medial approach in laparoscopic complete mesocolon excision.
Objective To explore the safety of local excision and watch and wait (W&W) strategy in patients with mid-low rectal cancer who achieved clinical complete response (cCR) or near-cCR after neoadjuvant chemoradiotherapy (nCRT). MethodsWe retrospectively reviewed patients with mid-low rectal cancer who achieved cCR or near-cCR after nCRT at Peking Union Medical College Hospital between July 2017 and July 2023 and divided them into two groups based on their treatment strategy: local excision group (n=30) and W&W group (n=37). The primary outcome was disease free survival (DFS), and the secondary outcomes were overall survival (OS), recurrence-free survival (RFS), and metastasis-free survival. ResultsBaseline characteristics (including age, gender, and so on) were balanced and comparable between the two groups (P>0.05). Postoperative pathology in the local excision group showed ypT0 in 16 cases (53.3%), ypT1 in 3 cases (10.00%), ypT2 in 10 cases (33.3%), and ypT3 in 1 case (3.3%). Among the 10 cases of cCR in the local excision group, 7 cases (70.0%) achieved a pathological complete response. Among the 20 cases of near-cCR in the local excision group, 9 cases (45.0%) achieved pathological complete response. The median follow-up time was 38 months (range, 2 to 74 months). In the W&W group, tumor regrowth occurred in 13 cases (35.1%), distant metastasis in 7 cases (18.9%), and cancer-related death in 4 cases (10.8%); in the local excision group, local recurrence occurred in 3 cases (10.0%), distant metastasis in 6 cases (20.0%), and cancer-related death in 3 cases (10.0%). The local recurrence/relapse rate was higher in the W&W group than that in the local excision group (χ2=5.758, P=0.016), while no significant differences were found in the distant metastasis rate (χ2=0.013, P=0.911) or mortality (χ2=0.012, P=1.000). The local excision group had superior DFS (HR=0.373, P=0.031) and RFS (HR=0.238, P=0.014) compared with the W&W group. However, no significant differences were found in OS (HR=0.780, P=0.745) or metastasis-free survival (HR=1.027, P=0.962). ConclusionsIn patients with mid-low rectal cancer who achieved cCR or near-cCR after nCRT, given the limited sample size and number of events in this study, local excision showed potential advantages in improving DFS and RFS, whereas OS, distant metastasis rate, and mortality were comparable between the two groups.