Lateral Lymph Node Size and Tumor Distance From Anal Verge Accurately Predict Positive Lateral Pelvic Lymph Nodes in Rectal Cancer: A Multi-Institutional Retrospective Cohort Study.

BACKGROUND: Lateral pelvic lymph node dissection improves oncological outcomes in rectal cancer patients with suspected lateral pelvic lymph node metastasis. However, the indication for this procedure remains unclear. OBJECTIVE: This study aimed to identify the predictive factors for lateral lymph node metastasis and the indications for lateral pelvic lymph node dissection. DESIGN: A multi-institutional retrospective study. SETTINGS: This study was conducted at 3 university hospitals. PATIENTS: This study involved 105 patients with locally advanced mid/low rectal cancer and clinically suspected lateral pelvic lymph node metastasis who underwent total mesorectal excision with lateral pelvic lymph node dissection between 2015 and 2020. MAIN OUTCOME MEASURES: Indications were set using lateral pelvic lymph node metastasis-associated preoperative factors. RESULTS: Among 105 patients, 36 (34.3%) had pathologically confirmed lateral pelvic lymph node metastasis and 77 (73.3%) underwent preoperative chemoradiation. Tumors located within 5 cm distance from the anal verge ( p = 0.02) and initial node size ≥ 6 mm ( p = 0.001) were significant predictors of lateral pelvic lymph node metastasis. The sensitivity was 100% (36/36) with a cutoff of 6 mm for the initial node size and 94.4% (34/36) with a cutoff of 8 mm for the initial node size. When using initial node size cutoffs of 8 mm for anal verge-to-tumor distance of >5 cm and 6 mm for anal verge-to-tumor distance of ≤5 cm, the sensitivity of lateral pelvic lymph node metastasis was found to be 100%. LIMITATIONS: The retrospective design and small sample size were the limitations of this study. CONCLUSION: Initial node size and tumor height were significant predictors of lateral pelvic lymph node metastasis. This study proposed that an initial node size of ≥8 mm with an anal verge-to-tumor distance of >5 cm and ≥6 mm with an anal verge-to-tumor distance of ≤5 cm are optimal indications for lateral pelvic lymph node dissection in rectal cancer. See Video Abstract at http://links.lww.com/DCR/C101 . EL TAMAO DEL GANGLIO LINFTICO LATERAL Y LA DISTANCIA DEL TUMOR DESDE EL BORDE ANAL PREDICEN CON PRECISIN LOS GANGLIOS LINFTICOS PLVICOS LATERALES POSITIVOS EN EL CNCER DE RECTO UN ESTUDIO DE COHORTE RETROSPECTIVO MULTIINSTITUCIONAL: ANTECEDENTES:La disección de los ganglios linfáticos pélvicos laterales mejora los resultados oncológicos en pacientes con cáncer de recto con sospecha de metástasis en los ganglios linfáticos pélvicos laterales. Sin embargo, la indicación de este procedimiento sigue sin estar clara.OBJETIVO:Nuestro objetivo fue identificar los factores predictivos de la metástasis de los ganglios linfáticos laterales y las indicaciones para la disección de los ganglios linfáticos pélvicos laterales.DISEÑO:Estudio retrospectivo multiinstitucional.AJUSTES:Este estudio se realizó en tres hospitales universitarios.PACIENTES:Este estudio involucró a 105 pacientes con cáncer de recto medio/bajo localmente avanzado y sospecha clínica de metástasis en los ganglios linfáticos pélvicos laterales que se sometieron a una escisión mesorrectal total con disección de los ganglios linfáticos pélvicos laterales entre 2015 y 2020.PRINCIPALES MEDIDAS DE RESULTADO:Las indicaciones se establecieron utilizando los factores preoperatorios asociados con la metástasis de los ganglios linfáticos pélvicos laterales.RESULTADOS:Entre 105 pacientes, 36 (34,3%) tenían metástasis en los ganglios linfáticos pélvicos laterales confirmada patológicamente y 77 (73,3%) se sometieron a quimiorradiación preoperatoria. Los tumores ubicados dentro de los 5 cm desde el borde anal ( p = 0,02) y el tamaño inicial del ganglio ( p = 0,001) fueron predictores significativos de metástasis en los ganglios linfáticos pélvicos laterales. La sensibilidad fue del 100 % (36/36), con un punto de corte de 6 mm para el tamaño inicial del ganglio, seguido de 8 mm para el tamaño inicial del ganglio (94,4%, 34/36). Cuando se utilizó un tamaño de corte inicial del ganglio de 8 mm para una distancia entre el borde anal y el tumor >5 cm y 6 mm para una distancia entre el borde anal y el tumor ≤5 cm, la sensibilidad de la metástasis en los ganglios linfáticos pélvicos laterales fue del 100 %.LIMITACIONES:El diseño retrospectivo y el pequeño tamaño de la muestra.CONCLUSIONES:El tamaño inicial del ganglio y la altura del tumor fueron predictores significativos de metástasis en los ganglios linfáticos pélvicos laterales. Este estudio propuso que un tamaño de ganglio inicial de ≥8 mm con un tumor a >5 cm del margen anal y ≥6 mm con un tumor a ≤5 cm del margen anal son indicaciones óptimas para la disección de los ganglios linfáticos pélvicos laterales en el cáncer de recto. Consulte Video Resumen en http://links.lww.com/DCR/C101 . (Traducción-Dr. Yolanda Colorado ).

Prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for non-metastatic right colon cancer (PIONEER study): study protocol of a multicentre single-arm trial.

BACKGROUND: The introduction of complete mesocolic excision (CME) with central vascular ligation (CVL) for right-sided colon cancer has improved the oncologic outcomes. Recently, we have introduced a modified CME (mCME) procedure that keeps the same principles as the originally described CME but with a more tailored approach. Some retrospective studies have reported the favourable oncologic outcomes of laparoscopic mCME for right-sided colon cancer; however, no prospective multicentre study has yet been conducted. METHODS: This study is a multi-institutional, prospective, single-arm study evaluating the oncologic outcomes of laparoscopic mCME for adenocarcinoma arising from the right side of the colon. A total of 250 patients will be recruited from five tertiary referral centres in South Korea. The primary outcome of this study is 3-year disease-free survival. Secondary outcome measures include 3-year overall survival, incidence of surgical complications, completeness of mCME, and distribution of metastatic lymph nodes. The quality of laparoscopic mCME will be assessed on the basis of photographs of the surgical specimen and the operation field after the completion of lymph node dissection. DISCUSSION: This is a prospective multicentre study to evaluate the oncologic outcomes of laparoscopic mCME for right-sided colon cancer. To the best of our knowledge, this will be the first study to prospectively and objectively assess the quality of laparoscopic mCME. The results will provide more evidence about oncologic outcomes with respect to the quality of laparoscopic mCME in right-sided colon cancer. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03992599 (June 20, 2019). The posted information will be updated as needed to reflect protocol amendments and study progress.

The fate of preserved sphincter in rectal cancer patients.

PURPOSE: Sphincter-saving surgery is widely accepted operative modality to treat rectal cancer. It often requires temporary diverting stoma to avoid the complications of anastomotic failure. This study investigates the cumulative failure rate in sphincter preservation for rectal cancer and the risk factors associated with the permanent stoma. METHODS: A retrospective study on 358 patients diagnosed with primary rectal cancer from 2009 to 2013 was conducted at a single institute. Three hundred and thirty-one out of 358 patients with rectal cancer located within 12 cm from the anal verge, who underwent sphincter-preserving surgery, were included in this study. The cumulative rate for permanent stoma was calculated. Univariate and multivariate analysis were performed, comparing the patients with stoma to the ones without. RESULTS: Temporary diverting stoma was created in 223 (82%) patients. After median follow-up of 42 months, 18 patients (6.6%) persistently used temporary stoma or required re-creation of stoma. Univariate analysis revealed that BMI, tumor location below 4 cm from the anal verge, coloanal anastomosis, anastomotic leakage, and local recurrence were significantly associated with persistent use or re-formation of stoma. Multivariate analysis showed that anastomotic leakage (OR 50.3; 95% CI, 10.1-250.1; p < 0.0001) and local recurrence (OR 11.3; 95% CI, 1.61-78.5; p = 0.015) were the independent risk factors. CONCLUSION: Patients with anastomotic leakage and local recurrence are at high risk for permanent stoma. Not only should patients be fully informed of possible failure in sphincter preservation preoperatively, but also patient-oriented decision should be made on patient-tailored surgical plan.

Are we doing too much?: local excision before radical surgery in early rectal cancer.

PURPOSE: In early rectal cancer cases, the use of local excision is increasing. The general indication for local excision is based on the preoperative stage, but there is often a discrepancy between pre and postoperative stages. We sought to determine the indications for local excision in T1 rectal adenocarcinoma patients by comparing the preoperative clinical and postoperative pathological stages. A second aim was to compare the oncologic outcomes between local excision and radical resection. METHODS: Between 2004 and 2014, 152 T1 rectal adenocarcinoma patients were enrolled. We divided the subjects into two groups, local excision and radical resection, depending on the modality of treatment the patients initially received. The group of patients who underwent radical resection was subsequently subdivided into "excisable" and "non-excisable" groups based on the postoperative pathology. RESULTS: Of 152 patients, 28 patients (18.4%) underwent local excision, while 124 patients (81.6%) underwent radical resection. Of 124 patients, in clinically suspected T2 or less and N0 (93) cases, 50 patients (53.8%) needed treatment beyond local excision, and local excision was sufficient for 43 patients (46.2%). The 3-year overall survival (p = 0.393) and 3-year disease-free survival (p = 0.076) between the local excision and radical resection groups showed no significant difference. CONCLUSIONS: The clinical T stage was overestimated in more than half of the cases. Therefore, if cT1/2 tumors with cN0 are suspected preoperatively, local excision is initially recommended and will allow for determination of underlying pathology. The clinician can then decide whether to monitor or intervene with radical resection.

Comparison of Long-Term Outcomes Between Emergency Surgery and Bridge to Surgery for Malignant Obstruction in Right-Sided Colon Cancer: A Multicenter Retrospective Study.

BACKGROUND: Malignant obstruction in right-sided colon (MORC) has traditionally been treated by emergency resection with primary anastomosis. The aim of this study was to evaluate short-term postoperative and long-term oncologic outcomes according to the surgical approach adopted for MORC. METHODS: A total of 1785 patients who underwent curative surgery for stage II or III colon cancer in seven hospitals were reviewed retrospectively. Seventy-four of 1785 patients had MORC. We compared the postoperative outcome and long-term oncologic outcome between the emergency surgery (ES) group (49 patients) and the bridge to surgery (BS) group (25 patients) for 74 patients with MORC. RESULTS: There were no differences in the length of the distal and proximal resection margin (p = 0.820 and p = 0.620) or the number of metastatic lymph nodes (p = 0.221). There were no differences in flatus passage (p = 0.242), start of diet (p = 0.336), hospital stay (p = 0.444), or postoperative morbidity (p = 0.762). The 5-year overall survival rates were 73.2 % in the ES group and 90.7 % in the BS group (p = 0.172). Moreover, the 5-year disease-free survival rates were 71.9 % in the ES group and 76.2 % in the BS group (p = 0.929). CONCLUSIONS: On the basis of the above results, the postoperative course of the ES group was similar to that of the BS group. In addition, the long-term oncologic outcome of the BS group was similar or slightly better than that of the ES group. BS after colonic stent may be an alternative option for MORC.

Role of autophagy-related protein expression in patients with rectal cancer treated with neoadjuvant chemoradiotherapy.

BACKGROUND: Autophagy, a cellular degradation process, has complex roles in tumourigenesis and resistance to cancer treatment in humans. The aim of this study was to explore the expression levels of autophagy-related proteins in patients with rectal cancer and evaluate their clinical role in the neoadjuvant chemoradiotherapy setting. METHODS: All specimens evaluated were obtained from 101 patients with colorectal cancer who had undergone neoadjuvant chemoradiotherapy and curative surgery. The primary outcomes measured were the expression levels of two autophagy-related proteins (microtubule-associated protein 1 light chain 3 beta (LC3ß) and beclin-1) by immunohistochemistry and their association with clinicopathological parameters and patient survival. RESULTS: Among the 101 patients, the frequency of high expression of beclin-1 was 31.7% (32/101) and that of LC3ß was 46.5% (47/101). A pathologic complete response was inversely associated with LC3ß expression (P = 0.003) and alterations in the expression of autophagy-related proteins (P = 0.046). In the multivariate analysis, however, autophagy-related protein expression did not show prognostic significance for relapse-free survival or overall survival. CONCLUSIONS: High expression of autophagy-related proteins shows a strong negative association with the efficacy of neoadjuvant chemoradiotherapy in patients with rectal cancer. Autophagy has clear implications as a therapeutic target with which to improve the efficacy of neoadjuvant chemoradiotherapy.

Early Removal of the Urinary Catheter After Total or Tumor-Specific Mesorectal Excision for Rectal Cancer Is Safe.

BACKGROUND: Total or tumor-specific mesorectal excision can preserve pelvic autonomic nerves during rectal cancer surgery and minimize urinary dysfunction. However, urinary catheterization several days in duration is a common practice after total or tumor-specific mesorectal excision. OBJECTIVE: This study aimed to evaluate the optimal duration of urinary catheterization after total or tumor-specific mesorectal excision for rectal cancer. DESIGN: This is a retrospective review of patients who underwent total or tumor-specific mesorectal excision for rectal cancer. SETTINGS: This study was performed in the colorectal division of a university-affiliated hospital. PATIENTS: Between March 2009 and February 2013, 236 patients fulfilled the inclusion criteria. Patients who underwent combined pelvic surgery and those who had postoperative complications with a Dindo grade III or more and a known urinary disease were excluded; the remaining 189 patients were evaluated. MAIN OUTCOME MEASURES: The primary outcome measure of this study was the incidence of postoperative urinary retention. RESULTS: The incidence of acute urinary retention was 4.8%. Urinary retention was not associated with the postoperative urinary catheterization duration (p = 0.99). Patients were assigned to 2 groups according to urinary catheterization duration (1 vs ≥ 2 days). No significant differences were observed between the 2 groups regarding urinary retention (4.8% for 1 day vs 4.7% for ≥ 2 days; p = 1.0). In a logistic regression analysis, age, sex, ASA classification, surgical procedure, surgical approach, stage, distance from the anal verge, rate of preoperative radiotherapy, duration of urinary catheterization, and time period of surgery were not associated with urinary retention. LIMITATIONS: This was a retrospective, single-center study. There is potential for selection bias. CONCLUSIONS: Our study showed that the urinary catheter could be safely removed on the first postoperative day after total or tumor-specific mesorectal excision.

Reduced luminal circumference of tumors plays a key role in anorectal function during the early period after neoadjuvant chemoradiation therapy in rectal cancer patients.

PURPOSE: The deterioration of anorectal function after neoadjuvant chemoradiation therapy (nCRT) combined with surgery for rectal cancer has not been well defined. The aim of this study was to evaluate the relationship between the tumor response to nCRT and changes in anorectal function during a short-term period after nCRT. METHODS: We analyzed 100 consecutive patients with available preoperative anorectal manometry data, both before and after nCRT, from 2010 to 2013. RESULTS: Comparing the manometric data before and after nCRT, the values reflecting rectal sensory function after nCRT was significantly lower than those before nCRT. However, in patients who experienced changed tumor morphology and a reduction in luminal circumferential ratio (LCIR) of tumor after nCRT, the values reflecting rectal sensory function were significantly less decreased after nCRT. On multivariate analysis, the reduction of LCIR after nCRT was a very important factor preventing the impairment of anorectal function during the short-term period in terms of the first rectal sensory threshold (RST) (P = 0.002), the RST of "desire to defecate" (P = 0.006), and rectal compliance (P = 0.003). Additionally, in linear regression analysis, the RST for the desire to defecate was positively affected by tumor morphology (P = 0.015) and the reduced LCIR (P = 0.025), and rectal compliance was positively affected by the reduced LCIR (P = 0.001). CONCLUSION: The nCRT impaired significantly rectal sensory function during the short-term period after nCRT and before a radical operation. However, this reduced LCIR of tumors after nCRT may prevent or minimize impediments to anorectal function during the short-term period after nCRT.

How much colonic redundancy could be obtained by splenic flexure mobilization in laparoscopic anterior or low anterior resection?

BACKGROUND AND OBJECTIVES: Splenic flexure mobilization (SFM) is performed to ensure a tension free anastomosis with an adequate resection margin in laparoscopic anterior resection (AR) or low anterior resection (LAR). This retrospective study was performed to determine the amount of colonic redundancy that can be expected by SFM. METHODS: Retrospective review of medical record for a total of 203 patients who underwent SFM during laparoscopic AR or LAR for the treatment of sigmoid colon or rectal cancer was performed. RESULTS: The obtained redundancy of the colon by SFM was 27.81 ± 7.29 cm from the sacral promontory. The redundancy of the colon by SFM with high ligation of the inferior mesenteric vein (IMV) (29.54 ± 7.17 cm from the sacral promontory) was greater than that with low ligation of the IMV (24.94 ± 6.07 cm from the sacral promontory, P < 0.0001). It took about 9.82% of the total operation time to perform SFM. There was no intraoperative complication during SFM. CONCLUSIONS: SFM during laparoscopic AR or LAR is a safe and feasible option. Based on the result of this study, one can gain about 27.81 cm redundancy of the colon by SFM.

Preoperative localization of potentially invisible colonic lesions on the laparoscopic operation field: using autologous blood tattooing.

PURPOSE: Preoperative colonoscopic (POC) localization is recommended for patients scheduled for elective laparoscopic colectomy for early colon cancer. Among the various localization method, POC tattooing localization has been widely used. Several dyes have been used for tattooing, but dye has disadvantages, including foreign body reactions. For this reason, we have used autologous blood tattooing for POC localization. This study aimed to evaluate the safety and efficacy of the autologous blood tattooing method. METHODS: This study included patients who required POC localization of the colonic neoplasm among the patients who were scheduled for elective colon resection. The indication for localization was early colon cancer (clinically T1 or T2) or colonic neoplasms that could not be resected endoscopically. POC autologous blood tattooing was performed after saline injection, and 2 hemoclips were applied. RESULTS: A total of 45 patients who underwent autologous blood tattooing and laparoscopic colectomy were included in this study. All POC localization sites were visible in the laparoscopic view. POC localization sites showed almost perfect agreement with intraoperative surgical findings. There were no complications like bowel perforation, peritonitis, hemoperitoneum, and mesenteric hematoma. CONCLUSION: Autologous blood is a safe and effective agent for localizing materials that can replace previous dyes. However, a large prospective case-control study is required for the routine application of this procedure in early colon cancer or colonic neoplasms.

The nutritional impact of diverting stoma-related complications in elderly rectal cancer patients.

PURPOSE: Diverting stomas following rectal cancer surgery can affect patients' quality of life, and their complications may negatively affect patients' long-term outcomes and quality of life. The purpose of this study is to investigate the relationship between diverting stoma-related complications and nutritional status. METHODS: In a retrospective study of 114 patients aged 65 years and older who underwent diverting loop ileostomy following rectal cancer surgery between June 2004 and March 2011, we analyzed retrospectively diverting stoma-related complications and nutrition status for the following time periods: before stoma construction, before stoma closure, and after stoma closure. RESULTS: Complications related to the diverting stoma developed in 24 (21.1%) patients and complications related to stoma closure in 11 (9.6%) patients. Nutritional screening performed prior to stoma closure showed that patients who experienced stoma formation-related complications had lower albumin levels (P = 0.016) and lower total lymphocytes (P = <0.0001). Body weight loss was more severe in patients with stoma-related complication (P = 0.036). CONCLUSIONS: Diverting stoma-related complications may affect patient's nutritional status. Stoma closure operation and proper nutritional support may be important for avoiding complications and improving patients' long-term outcomes and quality of life.

Glucose transporter 1 (GLUT1) of anaerobic glycolysis as predictive and prognostic values in neoadjuvant chemoradiotherapy and laparoscopic surgery for locally advanced rectal cancer.

PURPOSE: We investigated the relationships between biomarkers related to anaerobic glycolytic metabolism (GLUT1, LDH5, PDK1, and HIF-1α proteins), pathologic response, and prognosis. METHODS: All stage II and stage III rectal cancer patients had 50.4 Gy (1.8 Gy/day in 28 fractions) over 5.5 weeks, plus 5-fluorouracil (425 mg/m(2)/day) and leucovorin (20 mg/m(2)/day) bolus on days 1 to 5 and 29 to 33, and surgery was performed at 7 to 10 weeks after completion of all therapies. Expression of GLUT1, LDH5, PDK1, and HIF-1α proteins was determined by immunohistochemistry and was assessed in 104 patients with rectal cancer treated with neoadjuvant chemoradiotherapy. RESULTS: This study included stage II and III rectal cancer patients, and each stage accounted for each 50 % of the total cases. A high expression of GLUT1 protein was associated with a significantly lower rate of ypCR compared with low expression of GLUT1 protein (4.0 % vs. 27.8 %, respectively; p = 0.012). GLUT1 expression was also significantly higher in the poor response group (Grade 0, 1) than in the good response group (Grade 2, 3) (34.0 % vs. 14.8 %, respectively; p = 0.022). In recurrence analysis, the expression of GLUT1 protein demonstrated a significant correlation with time to recurrence, based on a log-rank method (p = 0.016). When analyzed by multiple Cox regression, the positive expression of GLUT1 was the most significant and independent unfavorable prognostic factor (p = 0.004). CONCLUSIONS: GLUT1 expression is a predictive and prognostic factor for pathologic complete response and recurrence in rectal cancer patients treated with 5-flurouracil and leucovorin neo-adjuvant chemoradiotherapy.

One-year experience of robotic transabdominal preperitoneal approach in a single institute: 2 different surgeons with different levels of experience.

Purpose: The robotic platform, an extension of minimally invasive procedures, is distributed nationwide and readily available. However, its application in inguinal hernia repair seems rare in Korea. This report aims to share our initial experience with robotic inguinal hernia repair. Methods: The patients who underwent robotic inguinal hernia repair by 2 different surgeons with different experiences at a single center were retrospectively analyzed. The surgical procedures were performed on all patients using the Da Vinci Xi robotic platform (Intuitive Surgical Inc). Patient demographics, operation variables, and postoperative outcomes were analyzed. Results: A total of 35 patients underwent robotic inguinal hernia repairs consecutively. The mean age was 55.03 ± 18.20 years. The majority of patients were male. The overall mean operation time was 103.98 ± 47.92 minutes for unilateral hernia surgery and 139.28 ± 46.07 minutes for bilateral surgery. None of the patients experienced intraoperative complications. However, postoperative complications were noticed in 8 patients: 3 with seroma formation, 1 with hematoma, 1 with superficial surgical site infection, and 3 with persistent pain at the operation site. Conclusion: This report demonstrates an early experience of hernia surgery using the robotic platform. The robotic approach for transabdominal preperitoneal hernia repair was completed without any significant intraoperative or postoperative complications. It may be a viable option as a minimally invasive technique. Cost-effectiveness, optimal procedural steps, and indications for the robotic approach remain to be further investigated.

The pattern of bowel dysfunction in patients with rectal cancer following the multimodal treatment: anorectal manometric measurements at before and after chemoradiation therapy, and postoperative 1 year.

PURPOSE: Bowel dysfunction commonly occurs in patients with locally advanced rectal cancer treated with a multimodal approach of chemoradiation therapy (CRT) combined with sphincter-preserving rectal resection. This study investigated the decline in anorectal function using sequential anorectal manometric measurements obtained before and after the multimodal treatment as well as at a 1-year follow-up. METHODS: This was a retrospective cohort study conducted in a single center. The study population consisted of patients with locally advanced mid- to low rectal cancer who received the preoperative CRT followed by sphincter-preserving surgery from 2012 to 2016. The anorectal manometric value measured after each treatment modality was compared to demonstrate the degree of decline in anorectal function. A generalized linear model of repeated measures was performed using the manometric values measured pre- and post-CRT, and at 12 months postoperatively. RESULTS: Overall, 100 patients with 3 consecutive manometric data were included in the final analysis. In the overall cohort study, the mean resting and maximal squeezing pressures showed insignificant decrement post-neoadjuvant CRT. At a 1-year postoperative follow-up, the maximal squeezing pressure significantly decreased. The maximal rectal sensory threshold demonstrated significant reduction consecutively after each following treatment (P<0.001). CONCLUSION: The short-term effect of neoadjuvant CRT on the anal sphincters was relatively trivial. The following sphincter-saving surgery resulted in a profound disruption of the anorectal function. Patients with rectal cancer should be consulted on the consequence of multimodal treatment.

Reappraisal of the Lymphatic Drainage System of the Distal Rectum: Functional Lymphatic Flow into the Presacral Space and Its Clinical Implication in Rectal Cancer Treatment.

Understanding the source and route of pelvic metastasis is essential to developing an optimal strategy for controlling local and systemic diseases of rectal cancer. This study aims to delineate the distribution of lymphatic channels and flow from the distal rectum. In fresh-frozen cadaveric hemipelvis specimens, the ligamentous attachment of the distal rectum to the pelvic floor muscles and the presacral fascia were evaluated. Using indocyanine green (ICG) fluorescence imaging, we simultaneously evaluated the gross anatomy of the lymphatic communication of the distal rectum. We also investigated the lymphatic flow in the pelvic cavity intraoperatively in rectal cancer patients who underwent radical rectal resection with total mesorectal excision (TME). In fresh cadavers, multiple small perforating lymphovascular branches exist in the retrorectal space, posteriorly connecting the mesorectum to the presacral fascia. The lymphatic flow from the distal rectum drains directly into the presacral space through the branches. In patients who underwent TME for rectal cancer, intraoperative ICG fluorescence signals were seen in the pelvic sidewalls and the presacral space. This anatomical study demonstrated that the lymphatic flow from the distal rectum runs directly to the pelvic lateral sidewalls and the presacral space, suggesting a possible route of metastasis in distal rectal cancer.

Assessment of Colorectal Anastomosis with Intraoperative Colonoscopy: Its Role in Reducing Anastomotic Complications.

The use of intraoperative colonoscopy (IOC) to evaluate the integrity of newly created anastomosis has been advocated by some surgeons. However, whether direct visualization of fresh anastomosis can help reduce anastomotic problems is still unclear. This study investigates the impact of immediate endoscopic assessment of colorectal anastomosis on anastomotic problems. This is a retrospective study conducted at a single center. Among six hundred forty-nine patients who underwent stapled anastomosis for left-sided colorectal cancer, the anastomotic complications were compared between patients who underwent IOC and those who did not. Additionally, patients with subsequent intervention after the IOC were compared to those without the intervention. Twenty-seven patients (5.0%) developed anastomotic leakage, and six (1.1%) experienced anastomotic bleeding postoperatively. Of the patients with IOC, 70 patients received reinforcement sutures to secure anastomotic stability. Of 70 patients, 39 patients showed abnormal findings in IOC. Thirty-seven patients (94.9%) who underwent reinforcement sutures did not develop postoperative anastomotic problems. This study demonstrates that IOC assessment with reinforcement sutures does not imminently reduce the rate of anastomotic complications. However, its use may play a role in detecting early technical failure and preventing postoperative anastomotic complications.

Robotic Lateral Pelvic Lymph Node Dissection Could Harvest More Lateral Pelvic Lymph Nodes over Laparoscopic Approach for Mid-to-Low Rectal Cancer: A Multi-Institutional Retrospective Cohort Study.

Lateral pelvic lymph node dissection (LPND) is a technically demanding procedure. This study aimed to compare the short-term outcomes of laparoscopic and robotic LPNDs. This multi-institutional retrospective study included 108 consecutive patients who underwent laparoscopic or robotic total mesorectal excision with LPND for locally advanced rectal cancer. There were 74 patients in the laparoscopic and 34 in the robotic groups. The median operation time was longer in the robotic group than in the laparoscopic group (353 vs. 275 min, p < 0.001). No patients underwent conversion to open surgery in either group. Pathological LPN metastases were observed in 24 and 8 patients in the laparoscopic and robotic groups, respectively (p = 0.347). Although the number of harvested mesorectal lymph nodes was similar (15.5 vs. 15.0, p = 0.968), the number of harvested LPNs was higher in the robotic than in the laparoscopic group (7.0 vs. 5.0, p = 0.004). Postoperative complications and length of hospital stay were similar (robotic vs. laparoscopic, 35.3% and 7 days vs. 37.8% and 7 days, respectively). Both laparoscopic and robotic LPND are safe and feasible for locally advanced rectal cancers, but robotic LPND showed more harvested lateral lymph node than laparoscopic LPND.

Differential Perspectives by Specialty on Oligometastatic Colorectal Cancer: A Korean Oligometastasis Working Group's Comparative Survey Study.

PURPOSE: Despite numerous studies on the optimal treatments for oligometastatic disease (OMD), there is no established interdisciplinary consensus on its diagnosis or classification. This survey-based study aimed to analyze the differential opinions of colorectal surgeons and radiation oncologists regarding the definition and treatment of OMD from the colorectal primary. MATERIALS AND METHODS: A total of 141 participants were included in this study, consisting of 63 radiation oncologists (44.7%) and 78 colorectal surgeons (55.3%). The survey consisted of 19 questions related to OMD, and the responses were analyzed using the chi-square test to determine statistical differences between the specialties. RESULTS: The radiation oncologists chose "bone" more frequently compared to the colorectal surgeons (19.2% vs. 36.5%, p=0.022), while colorectal surgeons favored "peritoneal seeding" (26.9% vs. 9.5%, p=0.009). Regarding the number of metastatic tumors, 48.3% of colorectal surgeons responded that "irrelevant, if all metastatic lesions are amendable to local therapy", while only 21.8% of radiation oncologist chose same answer. When asked about molecular diagnosis, most surgeons (74.8%) said it was important, but only 35.8% of radiation oncologists agreed. CONCLUSION: This study demonstrates that although radiation oncologists and colorectal surgeons agreed on a majority of aspects such as diagnostic imaging, biomarker, systemic therapy, and optimal timing of OMD, they also had quite different perspectives on several aspects of OMD. Understanding these differences is crucial to achieving multidisciplinary consensus on the definition and optimal management of OMD.