Anal Function Research Articles

Preoperative anal function assessment in sphincter-preserving surgery for rectal cancer: clinical significance and strategies

Sphincter-preserving surgery has become the mainstream approach for mid-to-low rectal cancer, yet postoperative anal dysfunction (low anterior resection syndrome, LARS) occurs in 30%-50% of patients, significantly impacting quality of life. This review systematically elaborates the clinical value of preoperative anal function assessment (mainly digital rectal examination), proposing a multidimensional evaluation system integrating anatomical (including high-resolution anorectal MRI, 3D transrectal ultrasound and dynamic contrast-enhanced ultrasound), physiological (anorectal amnometry and anal electromyography), and neurological assessments (including Parks scale, Wexner score, MSK-BFI scale and LARS score), alongside innovative strategies such as artificial intelligence and gut microbiome analysis. We advocate incorporating preoperative functional assessment into quality control standards for sphincter preservation, promoting a paradigm shift from "anatomical preservation" to "functional preservation".

Expert consensus on the protection of pelvic organ function in rectal cancer surgery (version 2025)

With the development of surgical techniques, adjuvant therapy and neoadjuvant therapy, the survival time of rectal cancer patients after surgery has been significantly improved, but organ dysfunction is still an important problem affecting the quality of life of patients after surgery. With the continuous deepening of clinical research and practice and the updating of relevant theories, more detailed and reliable evidence-based medical evidence has been accumulated in the field of pelvic organ function protection in rectal cancer surgery, and has been continuously verified in the clinical real world at home and abroad. In order to further improve the awareness of domestic physicians on the protection of organ function during the treatment of rectal cancer, standardize the evaluation methods and surgical methods, reduce the incidence of organ dysfunction, and thus improve the quality of life of patients, Society of Colon & Rectal Surgeons of Chinese College of Surgeons of Chinese Medical Doctor Association, Section of Colorectal Surgery of Branch of Surgery of Chinese Medical Association, National Health Commission Capacity Building and Continuing Education Center Colorectal Surgery Committee, and Colorectal and Anal Function Surgeons Committee of China Sexology Association organized the discussion among relevant experts. On the basis of the 2021 edition of the Chinese Expert Consensus on the Protection of Pelvic Organ Function in Rectal Cancer Surgery, the recent evidence-based medical evidence was analyzed and summarized, and the definition, risk factors, evaluation methods, prevention and other issues of organ dysfunction after rectal cancer surgery were analyzed with reference to relevant domestic and foreign studies and combined with clinical practice. Proposed the diagnosis, evaluation and treatment of pelvic organ dysfunction in rectal cancer surgery, and finally formed the "Chinese expert Consensus on the protection of pelvic organ function in rectal cancer surgery (version 2025)".

Review of the surgical methods of rectovaginal fistula treatment

Background: Rectovaginal fistula (RVF) is an abnormal connection between the rectum and the vagina, significantly impairing women’s quality of life and leading to psychological consequences. Despite advancements in various surgical techniques, a universally accepted treatment standard has yet to be established.Aim of the study: This review aims to summarize current strategies and emerging trends in the surgical management of RVF.Material and methods: A narrative review was conducted using PubMed and Google Scholar, with no publication year restrictions, up to February 2025. Keywords such as “rectovaginal fistula,” “surgery,” “Crohn’s disease,” and specific surgical techniques were combined using logical operators (AND, OR). Out of 2,578 records, 39 articles—original papers, meta-analyses, and case reports published in English—met the inclusion criteria and were analyzed.Results: Conservative management is recommended for small, minimally symptomatic fistulas. However, many patients ultimately require surgery, which varies depending on the fistula’s etiology and complexity. Minimally invasive procedures are preferred for simple, low-level fistulas. The Martius flap is suitable for low- and mid-level cases. Transabdominal approaches are reserved for high or radiation-induced fistulas and carry higher complication risks. Surgical decisions should be based on etiology, fistula size and location, anal sphincter function, tissue condition, and surgeon experience.Conclusions: RVF remains a challenging condition that requires individualized, multidisciplinary care. Future research should aim to refine surgical techniques, compare treatment outcomes by etiology and method, and include larger patient populations to support the development of robust clinical guidelines. Additionally, prospective comparative studies are essential to determine the most effective interventions for different RVF subtypes.

Outcomes of endoscopic submucosal dissection for the treatment of superficial anal squamous cell carcinoma: A multicenter international experience

Background and Study Aims: Data on the feasibility of endoscopic submucosal dissection (ESD) for the treatment of superficial anal squamous cell carcinoma (ASCC) is limited. This study aimed to evaluate the outcomes of ESD in this anatomical location. Patients and methods: This is a multicenter retrospective study including patients who underwent ESD for the treatment of superficial ASCC. Results: A total of 23 patients with superficial ASCC were included. The median lesion size was 24 mm (range, 9-65 mm), and the median procedure time was 62 minutes (range, 26-210 minutes). The accuracy of optical diagnosis using JES IPCL to predict final histology was 63.6%. En bloc and R0 resection were achieved in 22 (95.6%) and 18 (78.3%) patients, respectively. The curative resection rate was 73.9% (17/23). Three patients received additional complementary treatment. Delayed bleeding was observed in 4 patients (17.4%), with two of them requiring endoscopic hemostasis. Anal pain was reported in 9 (39.1%) patients and was effectively managed with analgesics. Fecal incontinence and anal stenosis occurred both in one patient during the perioperative period. During a median follow-up of 10.1 months (range, 0-69.6 months), no recurrences were observed. Conclusions: ESD is a feasible and effective treatment for superficial ASCC. Adverse events were successfully managed with medical or endoscopic therapy. ESD should be considered as first-line resection technique to prevent recurrence while preserving anal sphincter function.

Different tightening schemes in thread-drawing therapy and their effects on anal function recovery in patients with high simple anal fistula.

We aimed to compare the effects of different tightening schemes in thread-drawing therapy on the recovery of anal function in patients with high simple anal fistulas after treatment. One hundred patients with high simple anal fistulas who met the inclusion criteria were randomly divided into four groups of 25 patients each. All patients underwent low-level incision and high-level thread-drawing surgery. In the 1/5, 1/4, 1/3, and 1/2 groups, the rubber band cutting force was applied by tightening the surrounding muscle bundle to 1/5, 1/4, 1/3, and 1/2 of its circumference, respectively (using a graduated rubber band). Subsequent tightenings were also performed to the corresponding fractions of the circumference. The overall clinical efficacy, wound healing time, wound symptom score, anal function, and Wexner score were compared among the four groups. The 1/5 group had the longest wound healing time, longer than those of the 1/4, 1/3, and 1/2 groups (p < 0.05). On the seventh postoperative day, the 1/2 group had a higher wound symptom score than the 1/5, 1/4, and 1/3 groups (p < 0.05). Three months after surgery, patients in the 1/5 group had higher resting anal canal pressure and maximum anal canal systolic pressure than the other three groups; the 1/4 and 1/3 groups had higher values than the 1/2 group (p < 0.05). One month and 3 months after surgery, patients in the 1/2 group had the highest Wexner scores, higher than those in the 1/5, 1/4, and 1/3 groups (p < 0.05). Tightening schemes of the 1/4 and 1/3 groups were found to be optimal as they resulted in less postoperative pain and minimal impact on anal function.

Hirschsprung's disease prognosis: significance of the length of aganglionosis and reference value for the dilated segment resection length.

The appropriate length of resection for the dilated segment in Hirschsprung's disease (HSCR) remains a subject of debate, and the correlation between postoperative clinical outcomes has yet to be elucidated. This study aimed to explore the relationship between the dilated segment resection length (DSRL) and the short-term clinical outcome of HSCR, as well as to determine the optimal DSRL value. The clinical data of all children with HSCR who underwent a pull-through surgery at Shanxi Children's Hospital from May 2016 to September 2023 were analyzed retrospectively, the baseline characteristics such as sex, gestational age, family history, and complications such as soiling, perianal erosion, constipation were collected. The groups were stratified in recto-sigmoid aganglionosis (short-segment) and extended colonic (long-segment), and DSRL was divided into three groups: DSRL < 10 cm, 10 ≤ DSRL < 20 cm, and DSRL ≥ 20 cm. The Wingspread score system was used to evaluate anal function and analyze the short-term clinical outcome. A total of 223 children were included in the study, among which 104 cases had short-segment HSCR and 119 cases had long-segment HSCR. The median age at which pull-through surgery was performed was 4 months. In cases of short-segment HSCR, aside from preoperative anemia, baseline characteristics showed no statistically significant differences among the three groups. No statistically significant association was observed between DSRL, the total length of intestinal resection, the length of aganglionosis,and postoperative clinical outcomes.For short-segment HSCR, the best postoperative bowel function was observed when DSRL < 10 cm, with the optimal value being 7.25 cm. In cases of long-segment HSCR, no statistically significant differences in baseline characteristics were observed among the three groups. DSRL, the total length of intestinal resection and the length of aganglionosis all showed statistically significant differences in relation to soiling and perianal erosion. For long-segment HSCR, the best postoperative bowel function was observed when 10 ≤ DSRL < 20 cm, with the optimal value being 13.00 cm. Not only the dilated segment resection length matters for the outcome but also the length of aganglionosis. For short-segment HSCR, DSRL, the total length of intestinal resection and the length of aganglionosis showed no significant impact on short-term clinical outcomes. In contrast, these parameters in long-segment HSCR were significantly associated with soiling and perianal erosion, although overall patient quality of life remained satisfactory. Data from a single clinical center suggest that optimal clinical outcomes for children are achieved when the DSRL measurements are 7.25 cm for short-segment HSCR and 13.00 cm for long-segment HSCR.

Modified four-quadrant enhanced coloanal anastomosis (fqeCAA) for patients receiving intersphincteric resection.

e15620 Background: Intersphincteric resection (ISR) is a sphincter-preserving surgery for ultra-low rectal cancer (uLRC). The anastomosis techniques for ISR mainly includes immediate coloanal anastomosis (ICAA) and delayed coloanal anastomosis (DCAA), both approaches are related with high risks of anastomotic leakage (AL) and potential adverse effects on anal function. We propose the modified four-quadrant enhanced coloanal anastomosis (fqeCAA) technique, a modification of the hand-sewn coloanal anastomosis technique, to reduce tension at anastomotic site while attaching the new rectum to the anal by enhanced coloanal suture. The aim of the present study was to evaluate the safety of fqeCAA and its feasibility in reducing AL rate and exempting patients from protective stoma. Methods: uLRC patients underwent laparoscopic intersphincteric resection and fqeCAA between February 2024 and June 2024 were included. The simplified procedure for fqeCAA is as follows: 1) a four-quadrant discontinuous suture between the seromuscular layer of the colon and the external sphincter of the anus was performed to settle the bowel and reduce anastomotic tension; 2) the full-thick colon and the mucosal muscularis layer of the anal canal was sutured in a circle. Stoma was not routinely concepted after fqeCAA. Complication and postoperative anal function were estimated. Results: A total of 19 patients underwent intersphincteric resection and fqeCAA, including 15 (78.9%) male, 7 (36.8%) receiving neoradiochemotherapy, 4 (21.1%) receiving neochemotherapy, 7 (36.8%) ASA grade III. The median distance from tumor to anal edge was 3.6 [2.45-4.75] cm. All patients achieved R0 resection and finished fqeCAA procedure without stoma, with a median operation time of and 145 [120-155] and median blood loss 20 [10-50] ml. No intraoperative complications were observed. The mean distance from the anastomosis to the anal verge was 1.5 [1.0-2.0] cm. With a median follow-up of 8 mouths. Eight patients (42.1%) experienced perioperative complications, with only 1 (5.3%) patient requiring surgical intervention because of AL. The overall AL rate was 15.8% (3/19), among which only 1 need diversion stoma. The LARS score was 39 [36-41], while the Wexner score was 13 [10.5-14.5]. Conclusions: This single-center pilot study suggests that the fqeCAA technique is a safe procedure that allows selective patients to avoid temporary stoma formation. Long term anal function still need follow-up. Detail and treatment of complications. Complications Treatment of complications Neorectal prolapse Anal trimming Neorectal prolapse Anal trimming Anastomotic leakage（clinical） Diverting stoma Perianal infection Antibiotics, hip bath Anastomotic leakage（imageology） Antibiotics, hip bath uroschesis None Anastomotic leakage（ integrity of the anastomosis） Placing an anal draining tube Perianal infection Antibiotics, hip bath

Phase II trial of anti PD-1 monoclonal antibody and FOLFOXIRI combined with long-course radiotherapy as the total neoadjuvant treatment for proficient mismatch repair, locally advanced, low rectal cancer (PANFORTE).

e15621 Background: The current standard treatment for locally advanced low rectal cancer (LALRC) achieves a complete response (CR) rate of only 20–30%. Consequently, radical surgery frequently results in the loss of anal organs, severely affecting patients’ quality of life. Therefore, there is an urgent clinical need to identify novel strategies that can maximize tumor regression and preserve anal function. Recent trials has demonstrated radiotherapy showed a distinctive synergistic anti-tumor effect with immune checkpoint inhibitors. Therefore, this study aim to assess the efficacy and safety of an immunotherapy-based total neoadjuvant therapy (TNT) in patients with proficient mismatch repair (pMMR) LALRC. Methods: In this ongoing single-arm study, we plan to enroll 53 patients with pMMR LALRC. Inclusion criteria include ECOG performance status ≤ 1 and an inferior tumor margin distance from the anal verge (DAV) ≤ 5 cm. Eligible patients receive 4 cycles of FOLFOXIRI plus serplulimab (200 mg) . Subsequently, they undergo long-course radiotherapy combination with capecitabine and 2 cycles of serplulimab (200 mg), followed by another 4 cycles of FOLFOXIRI and serplulimab (200 mg) . The primary endpoint is CR rate with the sum of clinical complete response (cCR) and pathological complete response (pCR). Secondary endpoints include sphincter preservation rate and safety. Single-cell RNA (scRNA) sequencing was utilized to investigate the molecular characterization. Results: Between November 2023 and June 2024, 22 patients were enrolled with male percentage of 50%, median age of 59 years (IQR, 54–66) and median DAV of 4 cm (IQR, 3–5). 86.3% (19/22) patients completed the full TNT regimen. Among the 20 patients eligible for endpoint assessments, the overall CR rate was 75% (15/20), and the sphincter preservation rate was 95% (19/20). 11 (55%) patients achieving cCR opted for a watch-and-wait approach, whereas 9 patients underwent radical surgery. 20% (4/20) achieved pCR and 25% (5/20) had a tumor regression grade (TRG) of 2. The most common severe toxicity was neutropenia (grade 3, 27.3% [6/22]; grade 4, 36.4% [8/22]). One (4.6%, 1/22) patient experienced grade 4 hyperammonemia encephalopathy. Other grade 3 toxicities included decreased hemoglobin (13.6%, 3/22), diarrhea, myocarditis, myasthenia gravis, and thrombocytopenia (each 4.6%, 1/22). The scRNA sequencing indicated that non-CR patients exhibited lower T cell infiltration and weaker MHC-I/II signaling. Conclusions: Our study indicates that this TNT regimen significantly enhances CR rates and anal preservation in pMMR LALRC compared to historical benchmarks, with an acceptable safety profile. These findings suggest that this new approach may be an alternative treatment option for LALRC patients who strongly desire anal preservation. Clinical trial information: NCT06099951 .

Conducting stoma-free intersphincteric resection for ultra-low rectal cancers by selective delayed coloanal anastomosis, a single center experience.

e15622 Background: Intersphincteric resection (ISR) is aimed at preserving the anus in patients with ultra-low rectal cancers (uLRCs). Previous reports show anastomotic leakage (AL) rates after ISR are 8.4%-17.0% in patients undergoing immediate coloanal anastomosis (ICAA) and 3.0%-8.6% for delayed coloanal anastomosis (DCAA). Protective stoma is routinely performed for ISR in most centers, which means extra incision, a second operation, additional risk of ostomy hernia, and high-Output Stoma. The current study aims to evaluate the safety and feasibility of stoma-free ISR. Methods: We retrospectively reviewed uLRC patients who underwent laparoscopic stoma-free-ISR (La-sf-ISR) between March 2023 and March 2024 at Colorectal Cancer Center, West China Hospital, Sichuan University. Decision of ICAA or DCAA was made depending on patient features and intraoperative judgement. Complications and postoperative anal function were estimated, and primary outcome is Clavien-Dindo grade IIIb-IV (C-D IIIb-IV) complication. Results: A total of 166 uLRC patients underwent La-sf-ISR were included (90 DCAAs and 76 ICAAs). The median tumor distances to annal verge were 4.6 cm vs 4.2 cm in DCAA and ICAA (p = 0.117). The median follow-up time for DCAA and ICAA were 13 months and 14 months. The incidence of C-D IIIb-IV complications (11.1% vs. 13.1%, p = 0.671), overall complications (44.4% vs. 34.2%, P = 0.237), long-term complications (17.8% vs. 19.7%, p = 0.902), and reoperation rates (13.3% vs. 17.1%, P = 0.646) were comparable between DCAA and ICAA groups. The incidence of short-term complication was higher in DCAA group (30% vs. 15.8%, p = 0.049). In the DCAA, 9/90 (10%) patients experienced AL, 4/90 (4.4%) of whom created a stoma. In the ICAA, 9/76 (11.8%) patients had AL, 6/76 (7.9%) of whom needed a stoma. Notably, 2/90 (2.2%) patients in DCAA needed repeatedly anal trimming, and 3/76 (3.9%) patients in ICAA group needed anal trimming because of neorectal mucosal prolapse. The LARS score, major LARS rate, and the Wexner score were comparable between two groups (30 (20-39) vs. 28.5 (16.8-34.0) p = 0.114; 53% vs. 43% p = 0.27; 10 (7-13) vs. 9 (6-12) P = 0.258). Conclusions: With selective use of DCAA or ICAA, La-sf-ISR shows acceptable safety, and functional outcome, indicating its feasibility. Follow-up, complication, and stoma status. DCAA N=90 ICAA N=76 p.overall Time of follow-up 13.0 [12.0;15.8] 14.0 [13.0;15.0] Overall complication 40 (44.4%) 26 (34.2%) Short-term complication 27 (30.0%) 12 (15.8%) 0.049 Reoperation 12 (13.3%) 13 (17.1%) Clavien-Dindo III-IV comlication 10（11.1%） 10（13.1%） LARS 30.0 [22.0;39.0] 28.5 [16.8;34.0] Major LARS 40(53%) 24(43%) Wexner 10.0 [7.00;13.0] 9.00 [6.00;12.0] History of stoma creation 7 （7.8%） 9 (11.8%) Bearing a stoma 4 (4.5%) 7 (9.2%)

Artificial intelligence-based model to predict recurrence after local excision in T1 rectal cancer.

Artificial intelligence-based model to predict recurrence after local excision in T1 rectal cancer.

Staged Turnbull-Cutait pull-through anastomosis comparing with direct anastomosis plus prophylactic ileostomy in the treatment of low rectal cancer after internal sphincter resection (STAR-TAR): study protocol for a randomized controlled trial

BackgroundRecent advancements in the understanding of lower rectum anatomy, rectal cancer biology, and surgical techniques have emphasized the importance of radical surgery for low rectal cancer that balances oncological safety and anal function preservation. After total mesorectal excision (TME) and coloanal anastomosis, participants face high risks of anastomotic leakage and infection, often requiring a protective ileostomy. However, ileostomies themselves lead to significant complications, such as dehydration and chronic renal failure, and many participants cannot have their stomas reversed as planned. The Turnbull-Cutait procedure, involving delayed transanal pull-through rectal resection, has emerged as a safer alternative, reducing leakage complications and avoiding the need for a protective stoma. Recent studies support its use in challenging rectal cases, showing comparable or better outcomes than standard techniques. Despite these promising results, limited data exists on its application to intersphincteric resection (ISR) or intersphincteric dissection (ISD), which itself has higher complication rates. Therefore, further research is needed to evaluate this Turnbull-Cutait anastomosis procedure (delayed transanal pull-through) in ISR, comparing its complications, oncological outcomes, and functional results to those of traditional methods (direct anastomosis).This study is a prospective, multicenter, 1:1, non-inferiority, randomized controlled trial with 110 participants, divided into two groups: the staged Turnbull-Cutait pull-through anastomosis group (n = 55) and the direct anastomosis group (n = 55). The control group will undergo ISR with traditional anastomosis plus protective ileostomy, while the experimental group will receive the transanal pull-through and delayed anastomosis without ileostomy. The primary outcome is the 30-day overall postoperative complication rate, including anastomotic leakage, infection, and other complications. Secondary outcomes include long-term complications, total surgery time, anorectal function (measured by LARS and Wexner scores), urinary and sexual function, quality of life (EORTC QLQ–CR29 and FIQL), and 3-year disease-free survival (DFS) and overall survival (OS).DiscussionCurrently, there is a lack of systematic studies exploring the use of delayed pull-through anastomosis in intersphincteric resection (ISR) procedures. Existing research on this technique in low rectal cancer is limited to small, single-center, retrospective studies with low levels of evidence. Therefore, a multicenter, prospective, randomized controlled trial is needed to determine whether delayed pull-through anastomosis can serve as a viable alternative to ISR-coloanal anastomosis, offering comparable or lower rates of postoperative complications, as well as similar oncological outcomes and defecatory function. This study aims to provide higher-quality evidence through a larger, well-designed trial, which could significantly inform clinical practice in this under-explored area.Trial registrationClinicalTrials.gov NCT06662643. Registered on October 29, 2024.

Sarcopenia Is an Independent Risk Factor for the Decline in Anal Sphincter Function and Increased Levator Laxity in Women.

Pelvic floor disorders are prevalent in women. Sarcopenia, or age-related muscle mass loss, may be a contributing factor. We aimed to investigate the association between sarcopenia, as measured by the psoas muscle index (PMI), and pelvic floor and anal sphincter function in women with evacuation disorders. We conducted a retrospective analysis of data from women who underwent magnetic resonance defecography and high-resolution anorectal manometry. As an indicator of overall muscle mass measurement, PMI was computed at the L4 level. Women with evacuation disorders who had magnetic resonance imaging diagnosis of sarcopenia (98/264; 37.1%), were older and had lower body mass index ( P < 0.001), with comparable rates of parity and pelvic surgery. There was a significant association between diminished PMI and decreased anal resting ( P < 0.001) and squeeze ( P < 0.001) pressures, as well as increased levator hiatus length ( P = 0.004), descent ( P = 0.01), and anorectal angle ( P = 0.002). Patients with sarcopenia were more likely to have anal hypotension and hypocontractility ( P < 0.001), and increased levator hiatus laxity measurements ( P < 0.05), associated with lower obstructive defecation scores (9 vs 11, P = 0.003), and higher Wexner fecal incontinence scores (8 vs 4, P = 0.03). Sarcopenia was an independent risk factor of anal hypotension and hypocontractility, levator enlargement, and exaggerated levator hiatus descent. Sarcopenia significantly affects anal sphincter function and pelvic floor dynamics in women with evacuation disorders, serving as a risk factor of anal hypotension/hypocontractility and levator laxity. These findings highlight the need for integrated approaches in managing pelvic floor disorders, taking into account the role of muscle mass and strength in treatment strategies.

Evaluation of the RIFER procedure in treating high intersphincteric anal fistulas.

A high intersphincteric anal fistula is a common anorectal disease that is challenging to treat due to high recurrence rates and has the risk of sphincter damage, which can lead to incontinence. This study aimed to evaluate the efficacy and safety of the rectal incision, fistula excision, and reconstruction (RIFER) procedure for treating high intersphincteric anal fistulas. Twenty-six patients with high intersphincteric anal fistulas who were admitted to Nanjing Hospital of Traditional Chinese Medicine between September 2021 and March 2024 and underwent the RIFER procedure were included. Patients were followed up for 6 months, and treatment efficacy, recurrence, and postoperative complications after the RIFER procedure were assessed. The surgical cure rate of patients treated with RIFER was 100%, with no recurrence or postoperative complications during the follow-up period. The average wound-healing time was 45.40 days. Functional scoring indicators, such as the visual analog and Wexner anal function scores, improved at different postoperative time points. After the RIFER procedure, the incision scar score of most patients (18 of 25) was 0, and none of the patients reported keyhole-like anal deformities. The mean hospital stay was 10.15 days. The RIFER procedure demonstrated remarkable efficacy and safety in the treatment of high intersphincteric anal fistulas, with no recurrence or postoperative complications. This procedure is suitable for treating high intersphincteric anal fistulas in clinical practice.

Prognostic Value of Serum Insulin‐Like Growth Factor‐1 in Patients With Anal Fistula Treated by Incision‐Thread‐Drawing Surgery

ABSTRACTBackgroundAnal fistula is a chronic condition characterized by an abnormal tract between the anal canal and perianal skin, often leading to infection, inflammation, and impaired quality of life. Incision‐thread‐drawing surgery is the main treatment for anal fistula. However, the risk of poor postoperative healing remains significant. This study investigates the prognostic value of preoperative serum insulin‐like growth factor‐1 (IGF‐1) levels in predicting wound healing after incision‐thread‐drawing surgery for anal fistula.MethodsA total of 129 patients undergoing incision‐thread‐drawing surgery for anal fistula were enrolled. Patients were divided into a healing group (n = 87) and a non‐healing group (n = 42) based on wound healing status at 1 month post‐surgery. Serum IGF‐1 levels were measured preoperatively, and their association with wound healing, inflammatory cytokines, and postoperative anal function was analyzed using logistic regression, receiver operating characteristic (ROC) analysis, and Wexner Incontinence Score.ResultsPreoperative serum IGF‐1 levels were significantly lower in the non‐healing group (p &lt; 0.001). IGF‐1 levels above 174.9 ng/mL were associated with better wound healing (OR = 0.603, p = 0.005) and lower postoperative inflammation. Higher IGF‐1 levels correlated with improved anal function at 7 and 14 days post‐surgery (p &lt; 0.01).ConclusionPreoperative serum IGF‐1 levels are a valuable prognostic biomarker for predicting wound healing and postoperative recovery in patients undergoing incision‐thread‐drawing surgery for anal fistula, potentially guiding clinical decision‐making and patient management strategies.

A Porcine Model of Laparoscopic Intersphincteric Resection for Ultra-Low Rectal Cancer

Objective To develop a porcine model for laparoscopic intersphincteric resection (ISR) targeting ultra-low rectal cancer. Methods Six Bama mini-pigs underwent a standard laparoscopic ISR procedure: (1) Ligation and transection of the inferior mesenteric vessels; (2) Exposure and sparing of the pelvic autonomic nerves; (3) Dissection of the rectum; (4) Dissection and transection of hiatal ligament and rectourethralis muscle; (5) Transanal dissection of the anal canal; (6) Dissection of the intersphincteric space (ISS); (7) End-to-end handsewn coloanal anastomosis (CAA). Pathological evaluations were conducted to ascertain the precision of the ISR. Furthermore, postoperative fecal incontinence scores were systematically assessed on a weekly basis throughout a 12-week post-surgery follow-up period. Results All six pigs survived surgery without conversion to an open approach. There were no occurrences of incisional infection or any surgical complications, including anastomotic leakage, anastomotic bleeding, or ileus. Postoperatively, one pig manifested constipation and three exhibited anal redness, both conditions ameliorating within a week. No erosive ulcers were detected. Notably, all animals exhibited fecal staining on their tails within the first two weeks post-surgery, transitioning to formed feces by the third week. Improvement in defecation frequency was observed after 6 weeks, with a noticeable reduction in defecation areas after one month. Incontinence scores, evaluated three months post ISR surgery, revealed no significant abnormalities in anal function compared to preoperative assessments. Conclusions This study established a replicable porcine model for laparoscopic ISR, demonstrating its potential utility in clinical and fundamental research related to ultra-low rectal cancer treatment.

A multicentre prospective study of anal function after laparoscopic ultra-low rectal cancer surgery using a mixed-effects model.

Abdominoperineal resection with permanent colostomy has historically been performed for very low rectal cancer located near the anal canal. Anus-preserving surgeries, such as intersphincteric resection (ISR) and low anterior resection (LAR), have recently become more common. However, postoperative anal function is a concern in these surgeries when the anastomosis is very low. The aim of this study was to examine changes in anal function and factors that worsen anal function after surgery for rectal cancer. A multicentre (47 facilities), non-randomized, single-arm phase II trial was conducted prospectively using the Wexner score questionnaire between 2014 and 2017. A total of 278 patients who underwent laparoscopic surgery for clinical Stage I very low rectal cancer were analysed using a mixed-effects model. Anal function temporarily worsened 3 months after surgery, but gradually recovered and spontaneously returned to an acceptable level in 3 years. In a comparison of surgical procedures, anal function was significantly better after LAR than after any type of ISR. There was little difference in anal function after total ISR, subtotal ISR and partial ISR. In the mixed-effects model analysis, ISR and older age (≥75 years) were identified as independent factors that worsened postoperative anal function. The results showed early deterioration of anal function followed by gradual improvement to an acceptable level after surgery. There is a higher risk of poor postoperative anal function after ISR and in older patients, and these risk factors should be communicated to patients when obtaining consent for the surgery.

Colonic J-Pouch vs. straight colorectal reconstruction after anal preservation surgery for ultra-low rectal cancer: A prospective cohort study on quality of life and bowel function.

Colonic J-Pouch vs. straight colorectal reconstruction after anal preservation surgery for ultra-low rectal cancer: A prospective cohort study on quality of life and bowel function.

Quality of Life and Functional Outcomes in Patients With Locally Advanced Rectal Cancer Receiving Total Neoadjuvant Therapy Versus Concurrent Chemoradiation Therapy: An Analysis of the STELLAR Trial.

Quality of Life and Functional Outcomes in Patients With Locally Advanced Rectal Cancer Receiving Total Neoadjuvant Therapy Versus Concurrent Chemoradiation Therapy: An Analysis of the STELLAR Trial.

Microbial Photosynthetic Oxygenation and Radiotherapeutic Sensitization Enables Pyroptosis Induction for Combinatorial Cancer Therapy.

Rectal cancer surgery is challenging due to the complex anatomy, making it difficult to achieve clear surgical margins. Radiotherapy (RT) plays a crucial role, especially in treating locally recurrent rectal cancer and preserving anal function. However, its effectiveness is often limited by tumor hypoxia, particularly prevalent in hypoxic regions near the bowel wall in colorectal cancer. Hypoxia contributes to both radiation resistance and apoptosis resistance, compromising RT outcomes. To overcome hypoxia-driven radiotherapy resistance, this work designs and engineers a radiotherapy-sensitizing bioplatform for efficient cancer RT. It combines lanthanum oxide nanoparticles (La2O3 NPs) with cyanobacteria, which produces oxygen through photosynthesis. This bioplatform uniquely reduces tumor hypoxia, enhances radiation deposition, and improves RT efficacy. La2O3 NPs further enhance reactive oxygen species (ROS) production induced by radiation, triggering pyroptosis via the ROS-NLRP3-GSDMD pathway, while RT amplifies pyroptosis through GSDME, circumventing tumor apoptosis resistance. The further integrated thermosensitive hydrogels ensure precise localization of the bioplatform, reducing systemic toxicity and improving therapeutic specificity. Compared to conventional therapies, this dual-action system addresses hypoxia, RT resistance, and apoptosis resistance more effectively. In vivo and in vitro hypoxia models validate its potent anti-tumor efficacy, offering valuable insights for refining clinical treatment paradigms.

Outcomes of the Gant-Miwa-Thiersch Procedure Using the Leeds-Keio Mesh for Rectal Prolapse.

Several procedures are available for treating rectal prolapse (RP). This study aimed to determine the effectiveness of the Gant-Miwa-Thiersch (GMT) procedure using the Leeds-Keio mesh (LKM) as a treatment for RP. This retrospective observational study included all patients with RP who underwent the GMT procedure using the LKM at our hospital between January 2012 and December 2023. The surgery was performed under local or lumbar spinal anesthesia in the jackknife position. The outcome measures included perioperative complications, recurrence rate, and improvement in anal function. During the study period, 107 patients with RP underwent the GMT procedure. The median patient age was 81 years, the median length of prolapse was 7 cm, and the median duration of the surgery was 39 minutes. Postoperative complications were observed in 26 (24.3%) patients, including constipation in 21, mesh early exposure in three, mesh infection in one, and bleeding in one patient(s). The median observation period was 29 months, and recurrence of RP was observed in nine (10%) out of 90 patients evaluated for recurrence, with a cumulative 5-year recurrence rate of 10.9%. Of the 65 patients with preoperative fecal incontinence, 33 (50.8%) demonstrated improvement postoperatively. The GMT procedure using the LKM has a low recurrence rate. The LKM is suitable as a prosthetic material for the Thiersch procedure due to its high elasticity, which can enhance the therapeutic efficacy of the GMT procedure.