Long-term survival and functional outcomes of laparoscopic surgery for clinical stage I ultra-low rectal cancers located within 5 cm of the anal verge: A prospective phase II trial (Ultimate trial).

OBJECTIVE: To clarify the long-term oncological outcomes and postoperative anal, urinary, and sexual functions after laparoscopic surgery for clinical stage I very low rectal carcinoma located near the anal canal. SUMMARY BACKGROUND DATA: Laparoscopic surgery is widely applied for rectal cancer; however, concerns remain, with some studies showing poorer outcomes compared to open surgery. METHODS: This single-arm, phase II trial included patients registered preoperatively from 47 institutions in Japan. The planned sample size was 300. The primary endpoint was the 3-year local recurrence rate. Anal, urinary, and sexual functions were evaluated using a prospective questionnaire. RESULTS: Three-hundred patients were registered between January 2014 and March 2017. Anus-preserving surgery was performed in 278 (93%), including 172 who underwent intersphincteric resection (58%) and 106 (36%) who underwent low anterior resection. The 3-year cumulative local recurrence rate was 6.3%. At 3 years postoperatively, 87% of patients used their own anus, and the median incontinence score improved from 12 at 3 months to 8 at 3 years. Only 5% of patients had severe incontinence (incontinence score of 16 points). Postoperative urinary function evaluation showed that International Prostate Symptom Score and Overactive Bladder Symptom Score decreased 1 week after surgery, but recovered to preoperative level 1 month after surgery. International Consultation on Incontinence Questionnaire-Sort Form remained almost stable after surgery. Sexual function evaluation using the International Index of Erectile Function-5 and International Index of Erectile Function-15 revealed that the patients had deteriorated 3 months after surgery but had recovered only slightly by 6 months. CONCLUSIONS: Laparoscopic surgery achieves feasible long-term oncological outcomes and a high rate of anus preservation with moderate anal function, and an acceptable incontinence score. While urinary function recovered rapidly, sexual function showed poor recovery.

Robotic versus open and laparoscopic pelvic exenterations for pelvic cancer: a multicenter propensity-matched analysis in Japan.

BACKGROUND: Pelvic exenteration (PE) is the last resort for achieving a complete cure for pelvic cancer; however, it is burdensome for patients. Minimally invasive surgeries, including robot-assisted surgery, have been widely used to treat malignant tumors and have also recently been used in PE. This study aimed to evaluate the safety and efficacy of robot-assisted PE (RPE) by comparing the outcomes of open PE (OPE) with those of conventional laparoscopic PE (LPE) for treating pelvic tumors. METHODS: Following the ethics committee approval, a multicenter retrospective analysis of patients who underwent pelvic exenteration between January 2012 and October 2022 was conducted. Data on patient demographics, tumor characteristics, and perioperative outcomes were collected. A 1:1 propensity score-matched analysis was performed to minimize group selection bias. RESULTS: In total, 261 patients met the study criteria, of whom 61 underwent RPE, 90 underwent OPE, and 110 underwent LPE. After propensity score matching, 50 pairs were created for RPE and OPE and 59 for RPE and LPE. RPE was associated with significantly less blood loss (RPE vs. OPE: 408 mL vs. 2385 ml, p < 0.001), lower transfusion rate (RPE vs. OPE: 32% vs. 82%, p < 0.001), and lower rate of complications over Clavien-Dindo grade II (RPE vs. OPE: 48% vs. 74%, p = 0.013; RPE vs. LPE: 48% vs. 76%, p = 0.002). CONCLUSION: This multicenter study suggests that RPE reduces blood loss and transfusion compared with OPE and has a lower rate of complications compared with OPE and LPE in patients with locally advanced and recurrent pelvic tumors.

Effect of Biologics on the Risk of Advanced-Stage Inflammatory Bowel Disease-Associated Intestinal Cancer: A Nationwide Study.

INTRODUCTION: The aim of this study was to evaluate the effect of biologics on the risk of advanced-stage inflammatory bowel disease (IBD)-associated intestinal cancer from a nationwide multicenter data set. METHODS: The medical records of patients with Crohn's disease (CD) and ulcerative colitis (UC) diagnosed with IBD-associated intestinal neoplasia (dysplasia or cancer) from 1983 to 2020 were included in this study. Therapeutic agents were classified into 3 types: biologics, 5-aminosalicylic acid, and immunomodulators. The pathological cancer stage was compared based on the drug used in both patients with CD and UC. RESULTS: In total, 1,042 patients (214 CD and 828 UC patients) were included. None of the drugs were significantly associated with cancer stage in the patients with CD. In the patients with UC, an advanced cancer stage was significantly associated with less use of biologics (early stage: 7.7% vs advanced stage: 2.0%, P < 0.001), 5-aminosalicylic acid, and immunomodulators. Biologic use was associated with a lower incidence of advanced-stage cancer in patients diagnosed by regular surveillance (biologics [-] 24.5% vs [+] 9.1%, P = 0.043), but this was not the case for the other drugs. Multivariate analysis showed that biologic use was significantly associated with a lower risk of advanced-stage disease (odds ratio = 0.111 [95% confidence interval, 0.034-0.356], P < 0.001). DISCUSSION: Biologic use was associated with a lower risk of advanced IBD-associated cancer in patients with UC but not with CD. The mechanism of cancer progression between UC and CD may be different and needs to be further investigated.

Enhanced Clinical Utility of Molecular Budding Signature as a Recurrence Risk Determinant in Stage II and III Colon Cancer Patients.

BACKGROUND: A molecular budding signature (MBS), which consists of seven tumor budding-related genes, was recently presented as a prominent prognostic indicator in colon cancer (CC) using microarray data acquired from frozen specimens. This study aimed to confirm the predictive power of MBS for recurrence risk based on formalin-fixed, paraffin-embedded (FFPE) materials. METHODS: This research utilized the same microarray data from a prior multicenter study using FFPE whole tissue sections, which retrospectively reviewed 232 stage II CC patients without adjuvant chemotherapy and 302 stage III CC patients with adjuvant chemotherapy. All patients underwent upfront curative surgery without neoadjuvant therapy between 2009 and 2012. An MBS score was calculated using the mean of log2 [each signal] of seven genes (MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, and FOXC1) as described before. RESULTS: The MBS-low group exhibited a better relapse-free survival (RFS) than the MBS-high group in stage II (P = 0.0077) and in stage III CC patients (P = 0.0003). Multivariate analyses revealed that the MBS score was an independent prognostic factor in both stage II (P = 0.0257) and stage III patients (P = 0.0022). Especially among T4, N2, or both (high-risk) stage III patients, the MBS-low group demonstrated markedly better RFS compared with the MBS-high group (P = 0.0013). CONCLUSIONS: This study confirmed the predictive power of the MBS for recurrence risk by employing FFPE materials in stage II/III CC patients.

Specialty-Certified Colorectal Surgeons Demonstrate Favorable Short-term Surgical Outcomes for Laparoscopic Low Anterior Resection: Assessment of a Japanese Nationwide Database.

BACKGROUND: There are few studies on the impact of a colorectal-specific technically certified surgeon on good surgical outcomes for laparoscopic low anterior resection in the real world. OBJECTIVE: To evaluate the short-term outcomes of laparoscopic low anterior resection with the participation of a certified colorectal surgeon. DESIGN: This was a retrospective cohort study using a Japanese nationwide database. SETTING: This study was conducted as a project for the Japan Society of Endoscopic Surgery and the Japanese Society of Gastroenterological Surgery. PATIENTS: This study included 41,741 patients listed in the National Clinical Database who underwent laparoscopic low anterior resection performed by certified, noncertified, and colorectal-specific certified surgeons, according to the Endoscopic Surgical Skill Qualification System, from 2016 to 2018. MAIN OUTCOME MEASURES: Operative mortality rate and anastomotic leak rate were the primary outcome measures. RESULTS: Overall 30-day mortality and operative mortality were 0.2% and 0.3%, respectively, without significant differences between all kinds of certified and noncertified surgeon groups. Overall anastomotic leak rate was 9.3%, with a significant difference between the 2 groups. Colorectal- and stomach-certified groups had lower 30-day mortality and operative mortality than the biliary-certified and noncertified groups. The anastomotic leak rate was the lowest in the colorectal-certified group. Based on a logistic regression analysis using the risk-adjusted model, operative mortality was significantly higher in the biliary-certified group than in the colorectal-certified group. Moreover, anastomotic leak rate was significantly lower in the colorectal-certified group than in the stomach-certified and noncertified groups. LIMITATIONS: This study was a retrospective study, and there was a possibility of different definitions of anastomotic leak due to the use of a nationwide database. CONCLUSIONS: The participation of a colorectal-specific certified surgeon may decrease the risk of operative mortality and anastomotic leak for laparoscopic low anterior resection. CIRUJANO COLORRECTAL ALTAMENTE CALIFICADO PROVOCA RESULTADOS QUIRRGICOS FAVORABLES A CORTO PLAZO PARA LA RESECCIN ANTERIOR BAJA LAPAROSCPICA EVALUACIN DE LA BASE DE DATOS NACIONAL JAPONESA: ANTECEDENTES:Hay pocos estudios sobre el impacto de un cirujano certificado técnicamente especializado en cáncer colorrectal con un buen resultado quirúrgico para la resección anterior baja laparoscópica en el mundo real.OBJETIVO:Evaluar los resultados a corto plazo de la resección anterior baja laparoscópica con la participación de un cirujano colorrectal certificado.DISEÑO:Este fue un estudio de cohorte retrospectivo que utilizó una base de datos nacional japonesa.AJUSTE:Este estudio se realizó como un proyecto para la Sociedad Japonesa de Cirugía Endoscópica y la Sociedad Japonesa de Cirugía Gastroenterológica.PACIENTES:este estudio incluyó a 41 741 pacientes incluidos en la base de datos clínica nacional que se sometieron a una resección anterior baja laparoscópica realizada por cirujanos certificados, no certificados y certificados específicamente colorrectales, según el Sistema de calificación de habilidades quirúrgicas endoscópicas de 2016 a 2018.PRINCIPALES MEDIDAS DE RESULTADO:La tasa de mortalidad operatoria y la tasa de fuga anastomótica fueron los resultados primarios.RESULTADOS:La mortalidad general a los 30 días y la mortalidad operatoria fueron del 0,2 % y el 0,3 %, respectivamente, sin diferencias significativas entre los grupos de todos los tipos de cirujanos certificados y no certificados. La tasa global de fuga anastomótica fue del 9,3 %, con una diferencia significativa entre los dos grupos. Los grupos con certificación colorrectal y estomacal tuvieron una mortalidad a los 30 días y una mortalidad operatoria más bajas que los grupos con certificación biliar y sin certificación. La tasa de fuga anastomótica fue la más baja en el grupo certificado colorrectal. Con base en un análisis de regresión logística utilizando el modelo ajustado por riesgo, la mortalidad operatoria fue significativamente más alta en el grupo con certificación biliar que en el grupo con certificación colorrectal. Además, la tasa de fuga anastomótica fue significativamente más baja en el grupo con certificación colorrectal que en los grupos con certificación estomacal y sin certificación.LIMITACIONES:Este estudio fue retrospectivo y existía la posibilidad de diferentes definiciones de fuga anastomótica debido al uso de una base de datos nacional.CONCLUSIONES:La participación de un cirujano certificado en video específico colorrectal puede disminuir el riesgo de mortalidad operatoria y fuga anastomótica para la resección anterior baja laparoscópica. (Traducción-Dr. Mauricio Santamaria ).

Skill-qualified surgeons positively affect short-term outcomes after laparoscopic gastrectomy for gastric cancer: a survey of the National Clinical Database of Japan.

BACKGROUND: Proficiency of the operating surgeon is one of the most critical factors potentially associated with reductions in complications and surgery-related mortality. With video-rating systems having shown potential for assessing laparoscopic surgeons' proficiency, the Endoscopic Surgical Skill Qualification System (ESSQS) was developed by the Japan Society for Endoscopic Surgery to subjectively assess the proficiency of laparoscopic surgeons by rating applicants' non-edited case videos. We conducted a study to evaluate how ESSQS skill-qualified (SQ) surgeon involvement influences short-term outcomes of laparoscopic gastrectomy performed for gastric cancer. METHODS: Data from the National Clinical Database regarding laparoscopic distal and total gastrectomy performed for gastric cancer between January 2016 and December 2018 were analyzed. Operative mortality, defined as 30-day mortality or 90-day in-hospital mortality, and anastomotic leakage rates were compared per involvement vs. non-involvement of an SQ surgeon. Outcomes were also compared per involvement of a gastrectomy-, colectomy-, or cholecystectomy-qualified surgeon. The association between the area of qualification and operative mortality/anastomotic leakage was also analyzed with a generalized estimating equation logistic regression model used to account for patient-level risk factors and institutional differences. RESULTS: Of 104,093 laparoscopic distal gastrectomies, 52,143 were suitable for inclusion in the study; 30,366 (58.2%) were performed by an SQ surgeon. Of 43,978 laparoscopic total gastrectomies, 10,326 were suitable for inclusion; 6501 (63.0%) were performed by an SQ surgeon. Gastrectomy-qualified surgeons outperformed non-SQ surgeons in terms of both operative mortality and anastomotic leakage. They also outperformed cholecystectomy- and colectomy-qualified surgeons in terms of operative mortality or anastomotic leakage in distal and total gastrectomy, respectively. CONCLUSION: The ESSQS appears to discriminate laparoscopic surgeons who can be expected to achieve significantly improved gastrectomy outcomes.

Genome-Wide Association Study Identifies Genetic Polymorphisms Associated with Estimated Minimum Effective Concentration of Fentanyl in Patients Undergoing Laparoscopic-Assisted Colectomy.

Sensitivity to opioids varies widely among individuals. To identify potential candidate single-nucleotide polymorphisms (SNPs) that may significantly contribute to individual differences in the minimum effective concentration (MEC) of an opioid, fentanyl, we conducted a three-stage genome-wide association study (GWAS) using whole-genome genotyping arrays in 350 patients who underwent laparoscopic-assisted colectomy. To estimate the MEC of fentanyl, plasma and effect-site concentrations of fentanyl over the 24 h postoperative period were estimated with a pharmacokinetic simulation model based on initial bolus doses and subsequent patient-controlled analgesia doses of fentanyl. Plasma and effect-site MECs of fentanyl were indicated by fentanyl concentrations, estimated immediately before each patient-controlled analgesia dose. The GWAS revealed that an intergenic SNP, rs966775, that mapped to 5p13 had significant associations with the plasma MEC averaged over the 6 h postoperative period and the effect-site MEC averaged over the 12 h postoperative period. The minor G allele of rs966775 was associated with increases in these MECs of fentanyl. The nearest protein-coding gene around this SNP was DRD1, encoding the dopamine D1 receptor. In the gene-based analysis, the association was significant for the SERP2 gene in the dominant model. Our findings provide valuable information for personalized pain treatment after laparoscopic-assisted colectomy.

Management of inguinal lymph node metastases from rectal and anal canal adenocarcinoma.

AIM: The surgical treatment of inguinal lymph node (ILN) metastases secondary to anorectal adenocarcinoma remains controversial. This study aimed to clarify the surgical treatment and management of ILN metastasis according to its classification. METHODS: This retrospective, multi-centre, observational study included patients with synchronous or metachronous ILN metastases who were diagnosed with rectal or anal canal adenocarcinoma between January 1997 and December 2011. Treatment outcomes were analysed according to recurrence and prognosis. RESULTS: Among 1181 consecutively enrolled patients who received treatment for rectal or anal canal adenocarcinoma at 20 referral hospitals, 76 (6.4%) and 65 (5.5%) had synchronous and metachronous ILN metastases, respectively. Among 141 patients with ILN metastasis, differentiated carcinoma, solitary ILN metastasis and ILN dissection were identified as independent predictive factors associated with a favourable prognosis. No significant difference was found in the frequency of recurrence after ILN dissection between patients with synchronous (80.6%) or metachronous (81.0%) ILN metastases. Patients who underwent R0 resection of the primary tumour and ILN dissection had a 5-year survival rate of 41.3% after ILN dissection (34.1% and 53.1% for patients with synchronous and metachronous ILN metastases, respectively, P = 0.55). CONCLUSION: The ILN can be appropriately classified as a regional lymph node in rectal and anal canal adenocarcinoma. Moreover, aggressive ILN dissection might be effective in improving the prognosis of low rectal and anal canal adenocarcinoma with ILN metastases; thus, prophylactic ILN dissection is unnecessary.

Involvement of a skill-qualified surgeon favorably influences outcomes of laparoscopic cholecystectomy performed for acute cholecystitis.

OBJECTIVE: The Endoscopic Surgical Skill Qualification System (ESSQS) was developed by the Japan Society for Endoscopic Surgery as a means of subjectively assessing the proficiency of laparoscopic surgeons. We conducted a study to evaluate how involvement of an ESSQS skill-qualified (SQ) surgeon influences short-term outcomes of laparoscopic cholecystectomy performed for acute cholecystitis. Previous reports suggest that assessment of the video-rating system is a potential tool to discriminate laparoscopic surgeons' proficiency and top-rated surgeons face less surgical mortality and morbidity in bariatric surgery. METHODS: Data from the National Clinical Database regarding laparoscopic cholecystectomy performed for acute cholecystitis between January 2016 and December 2018 were analyzed. Outcomes were compared between patients grouped according to involvement vs. non-involvement of an SQ surgeon. Outcomes were also compared between patients grouped according to whether their operation was performed by biliary tract-, stomach-, or colon-qualified surgeon. RESULTS: Of the 309,998 laparoscopic cholecystectomies during the study period, 65,295 were suitable for inclusion in the study and 13,670 (20.9%) were performed by an SQ surgeon. Patients' clinical characteristics did not differ between groups. Thirty-day mortality was significantly lower in the SQ group (0.1%) 16/13,670 than in the non-SQ group (0.2%) 140/51,625 (P = 0.001). Thirty-day mortality was [0.1% (9/7173)] in the biliary tract-qualified group, [0.2% (5/3527)] in the stomach-qualified group, and [0.1% (2/3240)] in the colon-qualified group. CONCLUSION: Surgeons with ESSQS certification outperform the non-skilled surgeons in terms of surgical mortality in 30 and 90 days. Further verification of the value of the ESSQS is warranted and similar systems may be needed in countries across the world to ensure patient safety and control the quality of surgical treatments.

Feasibility of the semi-opened method of specimen resection for a circumferential resection margin in rectal cancer surgery: a multicenter study.

PURPOSE: A circumferential resection margin (CRM) > 1 mm is a surrogate marker of oncologic outcomes in rectal cancer patients. In Japan, because the mesentery is removed from the rectum, the CRM cannot be measured. This multicenter prospective study evaluates the feasibility of a resected specimen processing method that allows CRM measurement. METHODS: Fifty patients with rectal cancer were enrolled. Resected specimens were processed as previously reported. The primary outcomes were CRM measurement and the rate of CRM positivity. The secondary outcomes were the quality of total mesorectal excision, the possibility to visualize and sample the tumor, the number of harvested lymph nodes, and comparison between the pathological CRM and preoperative mesorectal fascia (MRF) involvement. This study was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry under identification number UMIN000031735. RESULTS: The CRM was measurable in all patients and found to be positive in three (6%). We confirmed tumor localization, sampled the tumor, and measured the distal margin in all patients. A median of 20 lymph nodes were harvested. The concordance rate between preoperative MRF involvement and pathological CRM status was 90%. CONCLUSION: A semi-opened rectal specimen with transverse slicing is a feasible method for measuring the CRM.

Consensus statement on smoking cessation in patients with pain.

Smoking is closely associated with the development of various cancers and tobacco-related illnesses such as cardiovascular and respiratory disorders. However, data are scarce on the relationship between smoking and both acute and chronic pain. In addition to nicotine, tobacco smoke contains more than 4000 different compounds. Although nicotine is not the sole cause of smoking-induced diseases, it plays a critical role in pain-related pathophysiology. Despite the acute analgesic effects of nicotine, long-term exposure leads to tolerance and increased pain sensitivity due to nicotinic acetylcholine receptor desensitization and neuronal plastic changes. The purpose of smoking cessation interventions in smoking patients with pain is primarily not only to reduce their pain and associated limitations in activities of daily living, but also to improve the outcomes of underlying pain-causing conditions and reduce the risks of tobacco-related disorders. This statement aims to summarize the available evidence on the impact of smoking on pain and to inform medical professionals of the significance of smoking cessation in patients with pain.

Evaluation of a 55-gene classifier as a prognostic biomarker for adjuvant chemotherapy in stage III colon cancer patients.

BACKGROUND: Adjuvant chemotherapy reduces the risk of recurrence of stage III colon cancer (CC). However, more effective prognostic and predictive biomarkers are needed for better treatment stratification of affected patients. Here, we constructed a 55-gene classifier (55GC) and investigated its utility for classifying patients with stage III CC. METHODS: We retrospectively identified patients aged 20-79 years, with stage III CC, who received adjuvant chemotherapy with or without oxaliplatin, between the years 2009 and 2012. RESULTS: Among 938 eligible patients, 203 and 201 patients who received adjuvant chemotherapy with and without oxaliplatin, respectively, were selected by propensity score matching. Of these, 95 patients from each group were analyzed, and their 5-year relapse-free survival (RFS) rates with and without oxaliplatin were 73.7 and 77.1%, respectively. The hazard ratios for 5-year RFS following adjuvant chemotherapy (fluoropyrimidine), with and without oxaliplatin, were 1.241 (95% CI, 0.465-3.308; P = 0.67) and 0.791 (95% CI, 0.329-1.901; P = 0.60), respectively. Stratification using the 55GC revealed that 52 (27.3%), 78 (41.1%), and 60 (31.6%) patients had microsatellite instability (MSI)-like, chromosomal instability (CIN)-like, and stromal subtypes, respectively. The 5-year RFS rates were 84.3 and 72.0% in patients treated with and without oxaliplatin, respectively, for the MSI-like subtype (HR, 0.495; 95% CI, 0.145-1.692; P = 0.25). No differences in RFS rates were noted in the CIN-like or stromal subtypes. Stratification by cancer sidedness for each subtype showed improved RFS only in patients with left-sided primary cancer treated with oxaliplatin for the MSI-like subtype (P = 0.007). The 5-year RFS rates of the MSI-like subtype in left-sided cancer patients were 100 and 53.9% with and without oxaliplatin, respectively. CONCLUSIONS: Subclassification using 55GC and tumor sidedness revealed increased RFS in patients within the MSI-like subtype with stage III left-sided CC treated with fluoropyrimidine and oxaliplatin compared to those treated without oxaliplatin. However, the predictive power of 55GC subtyping alone did not reach statistical significance in this cohort, warranting larger prospective studies. TRIAL REGISTRATION: The study protocol was registered in the University Hospital Medical Education Network (UMIN) clinical trial registry (UMIN study ID: 000023879 ).

Calbindin-Positive Neurons Co-express Functional Markers in a Location-Dependent Manner Within the A11 Region of the Rat Brain.

The A11 region plays a role in numerous physiological functions, including pain and locomotor activity, and consists of a variety of neurons including GABAergic, calbindin positive (Calb+), and dopaminergic (DA) neurons. However, the neurochemical nature of Calb+ neurons and their regulatory role in the A11 region remain largely unknown. In this study, we examined the kind of functional markers co-expressed in the Calb+ neurons using sections from 8-week-old rats. To examine a marker related to classical neurotransmitters, we performed in situ hybridization for vesicular glutamate transporter 2 (vGluT2) or glutamate decarboxylase (GAD) 65 and 67, in conjunction with Calb immunohistochemistry. We found cellular co-expression of Calb with vGluT2 or GAD65/67 throughout the A11 region. Nearly all Calb+/GAD65/67+ neurons were found in the rostral-middle aspect of the A11 region. In contrast, Calb+/vGluT2+ neurons were found predominantly in the middle-caudal aspect of the A11 region. For receptors and neuropeptides, we performed immunohistochemistry for androgen receptor (AR), estrogen receptors (ERα and ERß), and calcitonin gene-related peptide (CGRP). We found that Calb+ neurons co-expressed AR in the rostral aspect of the A11 region in both male and female rats. However, we rarely find cellular co-expression of Calb with ERα or ERß in this region. For CGRP, we found both Calb+ neurons with or without CGRP expression. These results demonstrate that Calb+ neurons co-express many functional markers. Calb+ neurons have a distinct distribution pattern and may play a variety of regulatory roles, depending on their location within the A11 region.

Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification: the Japanese study group for postoperative follow-up of colorectal cancer.

PURPOSE: The purpose of the study was to compare staging of stage II colon cancer using the number of retrieved lymph nodes (RN) to current TNM staging for stratification of prognosis. METHODS: The subjects were 6307 patients with stage II colon cancer who underwent curative resection at 24 Japanese institutions. The cutoff for the number of RN was established using Akaike information criterion (AIC) values for relapse-free survival (RFS) and overall survival (OS). Comparison of survival using TNM and T + RN (TRN) staging was performed using a Cox proportional hazards regression model. RESULTS: AIC was lowest for 14 retrieved lymph nodes for RFS and OS. This number was used as the cutoff. In multivariate analysis, age (≥ 69), male gender, V1, CEA (> 5), pT (T4a, T4b), and RN-L were independent factors associated with RFS and OS. Six combinations of pT and RN categories were used to establish three subgroups: TRN stages IIA, IIB, and IIC. The 5-year RFS was 83.9%, 72.3%, and 71.8% in TNM stages IIA, IIB, and IIC; and 86.0%, 76.9%, and 60.3% in TRN stages IIA, IIB, and IIC. The 5-year OS was 90.0%, 81.3%, and 82.6% for the TNM stages; and 91.6%, 85.0%, and 71.9% for the TRN stages. The AIC for RFS was lower for TRN (22,318.2) than for TNM (22,390.6), and that for OS was also lower for TRN (16,285.3) than for TNM (16,355.1). CONCLUSION: Stage II colon cancer staging using the number of retrieved lymph nodes may be superior to current TNM staging for prognosis stratification.

Linear stapler anastomosis for esophagogastrostomy in laparoscopic proximal gastrectomy reduce reflux esophagitis.

PURPOSE: There are various reconstruction methods for Laparoscopic proximal gastrectomy (LPG), such as esophagogastrostomy (EG), double-tract reconstruction, and jejunal interposition. We have performed EG using a circular stapler (OrVil) from 2013 and using a linear stapler from 2017. The aim of this retrospective study was to clarify which stapler is better for EG for LPG. METHODS: The data of 84 patients who underwent EG for LPG between January 2013 and September 2019 were analyzed. EG with fundoplication was done using a circular stapler (OrVil) in 45 patients (CS group) and a linear stapler in 39 patients (LS group). The patients' medical records were reviewed. Clinical symptoms were obtained by interview at each outpatient consultation. All patients underwent postoperative 1-year follow-up endoscopy. To minimize bias between the two groups, propensity scores were calculated using a logistic regression model. After propensity-score matching, 60 patients (30 in the CS group and 30 in the LS group) were studied. RESULTS: Patient characteristics, operative outcomes were similar in two groups. Anastomotic leakage occurred in one patient (3.3%) in both groups. Anastomotic stenosis occurred in five patients (16.7%) in the CS group and two patients (6.7%) in the LS group. The rate of patients with severe reflux esophagitis (grade C or D) was significantly lower in the LS group (3.4%) than in the CS group (26.7%) (p = 0.026). CONCLUSIONS: EG with a linear stapler could reduce the risk of severe reflux esophagitis, and it could be a safe and feasible anastomosis for patients after LPG.

C-reactive protein adjusted for body mass index as a predictor of postoperative complications following laparoscopic gastrectomy for gastric cancer.

PURPOSE: This study aimed to clarify the relationship between obesity and postoperative C-reactive protein (CRP) and assess the usefulness of obesity status-adjusted CRP levels for predicting early complications following laparoscopic gastrectomy for gastric cancer. METHODS: This study retrospectively analyzed 527 patients who underwent laparoscopic gastrectomy for gastric cancer between January 2013 and March 2019. Patients were classified into three groups according to body mass index (BMI): BMI < 20; BMI ≥ 20 to < 25; and BMI ≥ 25. The correlation between BMI and perioperative CRP was investigated in 447 patients, excluding 80 with postoperative complications. The optimal CRP cutoff value of Clavien-Dindo (CD) grade ≥ 3 for predicting severe complications for each group was determined. RESULTS: BMI was significantly correlated with CRP on postoperative day (POD) 3 (p < 0.001) in 447 patients without complications. According to the receiver operating characteristic curve analysis, CRP cutoff values on POD 3 for predicting severe complications were 92.4, 111.1, and 171.9 in the BMI < 20, BMI ≥ 20 to < 25, and BMI ≥ 25 groups, respectively. In multivariate analysis for CD grade ≥ 3 complications, cardiac history and POD 3 CRP levels higher than the adjusted cutoff were identified as independent factors significantly associated with severe complications (p = 0.021 and 0.015, respectively). CONCLUSION: CRP cutoff values on POD 3 adjusted for BMI were useful for predicting severe complications in gastrectomy for gastric cancer.

Pedunculated early colorectal cancer with nodal metastasis: a case report.

BACKGROUND: Pedunculated polyps are more likely to be amenable to complete resection than non-pedunculated early colorectal cancers and rarely require additional surgery. We encountered a patient with a pedunculated early colorectal cancer that consisted of poorly differentiated adenocarcinoma with lymphatic invasion. We performed an additional bowel resection and found nodal metastasis. CASE PRESENTATION: A 43-year-old woman underwent colonoscopy after a positive fecal occult blood test. The colonoscopist found a 20-mm pedunculated polyp in the descending colon and performed endoscopic resection. Histopathologic examination revealed non-solid type poorly differentiated adenocarcinoma. The lesion invaded the submucosa (3500 µm from the muscularis mucosa) and demonstrated lymphatic invasion. In spite of the early stage of this cancer, the patient was considered at high risk for nodal metastasis. She was referred to our institution, where she underwent bowel resection. Although there was no residual cancer after her endoscopic resection, a metastatic lesion was found in one regional lymph node. The patient is undergoing postoperative adjuvant chemotherapy, and there has been no evidence of recurrence 3 months after the second surgery. CONCLUSIONS: Additional bowel resection is indicated for patients with pedunculated polyps and multiple risk factors for nodal metastasis, such as poorly differentiated adenocarcinoma and lymphatic invasion. We encountered just such a patient who did have a nodal metastasis; herein, we report her case history with a review of the literature.

Can general surgeons perform laparoscopic surgery independently within 10 years of training? A nationwide survey on laparoscopic surgery training in Japan.

PURPOSE: There is no standard program for laparoscopic surgery training in Japan, and competency in these procedures does not require the acquisition of board certification. The purpose of this survey was to investigate the current status of laparoscopic surgery training in Japan. METHODS: A questionnaire survey was mailed to 2296 members of the Japan Society for Endoscopic Surgery who were between postgraduate year 3 and 10. The questionnaire inquired about laparoscopic surgical training conditions, operation case numbers, and autonomy in eight laparoscopic procedures. RESULTS: The total response rate was 28.1%. The number of cases required to perform procedures independently was demonstrated. Most participants felt confident in performing laparoscopic appendectomy and cholecystectomy; however, they felt less confident about performing laparoscopic colectomy and gastrectomy. CONCLUSIONS: The information from this survey may be useful for surgical educators, surgical societies, and the board certification council for rebuilding the surgical training system in Japan.

Is prophylactic lateral lymph node dissection needed for lower rectal cancer? A single-center retrospective study.

BACKGROUND: The effectiveness of prophylactic lateral lymph node dissection (LLND) in treating patients with lower rectal cancer remains controversial and has not been clearly established. Therefore, we aimed to retrospectively analyze the survival impact of prophylactic LLND in patients with lower rectal cancer. METHODS: Data of 301 patients with lower rectal cancer (tumor's lower edge on the anal side of the peritoneal reflexion) with clinical T3 disease and negative preoperative lateral lymph node metastasis, who underwent radical resection (R0) at our hospital between April 2007 and March 2017, were included in this study. Patients who received preoperative chemotherapy or radiotherapy were excluded. The relapse-free survival (RFS) and overall survival (OS) rates were compared between the dissection (prophylactic LLND, n = 37) and non-dissection (no prophylactic LLND, n = 264) groups. RESULTS: Significantly fewer men and younger patients were noted in the dissection group than in the non-dissection group. Post-surgery 3- and 5-year RFS rates were 69.6% and 66.8% in the dissection group and 75.1% and 72.5% in the non-dissection group, respectively (5-year post-surgery RFS, p = 0.58). In the dissection and non-dissection groups, the 5-year OS rates were 86.5% and 79.7%, respectively (p = 0.29), and the 5-year cancer-specific survival rates were 88.9% and 86.0%, respectively (p = 0.29), with no significant differences. Lateral lymph node recurrence was observed in one (2.7%) and 10 patients (3.8%) in the dissection and non-dissection groups, respectively, and there was no significant difference between the groups. CONCLUSIONS: In this study, the effectiveness of prophylactic LLND was limited in patients with > T3 lower rectal cancer with no evidence of preoperative lymph node metastasis. Prophylactic LLND may not be necessary if there is no preoperative lymph node metastasis, even if the invasion depth is T3 or higher.

Robot-assisted surgery with Senhance robotic system for colon cancer: our original single-incision plus 2-port procedure and a review of the literature.

BACKGROUND: The Senhance robotic system provides such advantages as an eye-tracking camera control system, haptic feedback, operator comfort, and reusable endoscopic instruments. The aim of this small study was to assess the feasibility and safety of performing a reduced-port robot-assisted colectomy for colon cancer with the use of a novel robotic system. METHODS: This was a single-center retrospective study of eight patients with colon cancer who underwent single-incision plus 2-port robot-assisted colectomy with the Senhance robotic system (SILS+2-S) between December 2019 and March 2020 at our hospital. Data on perioperative outcomes, which included operative time, operative blood loss, length of hospitalization, postoperative complications, and histopathological results, were collected prospectively. RESULTS: The mean patient age was 70.9 years and the mean body mass index was 24.4 kg/m2. One patient was converted to laparoscopy due to a damaged scope holder. The mean operative and console times were 229.1 and 139.1 min, respectively. The mean intraoperative blood loss was 49.4 ml. The mean length of the umbilical incision was 3.0 cm. The mean number of harvested lymph nodes was 18.3. The surgical margins were negative in all eight patients. There was neither morbidity nor mortality associated with the procedure, and no Clavien-Dindo classification Grade II-IV complications occurred. CONCLUSIONS: SILS+2-S is a safe and feasible approach for patients with colon cancer. Further studies are needed to validate the advantages of SILS+2-S and to evaluate the long-term oncological outcomes.