Influence of proficiency in conventional laparoscopic surgery in colorectal cancer on the introduction of robotic surgery.

Purpose: Although there have been many reports on learning curves for robotic surgery, it is unclear how surgeons' conventional laparoscopic surgical skills influence their ability in performing robotic surgery for colorectal cancer (CRC). The aim of this study was to determine the surgical outcomes of robotic surgery for CRC during the induction phase by skilled laparoscopic surgeons.

Methods: Surgical outcomes of consecutive CRC cases between January 2021 and March 2023 following the skilled phase of laparoscopic surgery and introductory phase of robotic surgery performed by three skilled laparoscopic surgeons were compared.

Temporal dynamics of RAS mutations in circulating tumor DNA in metastatic colorectal cancer: clinical significance of mutation loss during treatment.

Purpose: In metastatic colorectal cancer (mCRC), RAS mutation loss may occur during the standard-of-care regimen. In this study, we aimed to investigate the temporal dynamics of the RAS gene and its clinical significance.

Methods: This was a retrospective, single-center study that included 82 patients with tissue RAS-mutant (RAS-MT) mCRC who underwent circulating tumor DNA (ctDNA) RAS monitoring between January, 2013-April, 2023.

True significance of the number of retrieved lymph nodes in stage II colon cancer resected by minimally invasive surgery: Influence of tumor sidedness.

Background: In patients with stage II colon cancer (CC) undergoing minimally invasive surgery, the association between the clinical significance of lymph node yield and tumor localization remains unknown. We aimed to determine the optimal number of lymph nodes to be retrieved based on tumor localization in patients with stage II CC undergoing minimally invasive surgery.

Methods: This was a multicenter retrospective study.

Robotic surgery after total neoadjuvant therapy for rectal cancer: pitfalls of beyond total mesorectal excision for patients with sidewall invasion.

Aim: Total neoadjuvant therapy (TNT) for locally advanced rectal cancer (LARC) is rapidly spreading. The robotic surgical techniques to approach lateral invasion, such as that of the pelvic plexus, have not yet been established. In this technical note, we present a video illustrating a surgical technique for lateral invasion using our novel technique and discuss its pitfalls.

Clinical Significance of the Post/Preoperative Anti-p53 Antibody Ratio in Predicting the Prognosis of Patients with Colorectal Cancer after Curative Surgery and Its Usefulness in Combination with Carcinoembryonic Antigen.

Introduction: Anti-p53 antibody (p53Ab) is useful for monitoring colorectal cancer (CRC) recurrence. We retrospectively analyzed the clinical impact of p53Ab ratio (p53R) before and after surgery to predict recurrence in patients with CRC.

Methods: In total, 1,223 patients with stage I-III CRC who underwent curative surgery between January 2005 and December 2019 were enrolled in this retrospective study.

Short- and long-term outcomes of transanal decompression tube and self-expandable metallic stent for obstructive colorectal cancer based on a multicenter database (KYCC2110).

Aim: There are well-known methods for decompressing the colorectal tract before surgery, including transanal decompression tubes (TDT) and self-expanding metallic stents (SEMS). This study aimed to compare the short and long-term results in patients with malignant large bowel obstruction in whom TDT or SEMS were placed before surgery.

Methods: This retrospective observational study enrolled 225 patients with malignant large bowel obstruction in whom TDT or SEMS were placed preoperatively and underwent R0 resection between 2008 and 2020.

Novel approach toward minimally invasive surgery for mid-transverse colon cancer: 'moving the left colon' technique.

Aim: During surgery for mid-transverse colon cancer (MTC), surgeons often face the dilemma of whether to mobilize the hepatic or splenic flexure. There is no established optimal minimally invasive surgical procedure for MTC.

Methods: We present our novel minimally invasive surgical technique, called the 'moving the left colon' technique for MTC, along with a video demonstration.

Analysis of surgical outcomes of laparoscopic versus open surgery for locally advanced mid-transverse colon cancer.

Purpose: This study compared the surgical outcomes between laparoscopic colectomy (LC) and open colectomy (OC) for mid-transverse colon cancer (MTC).

Methods: This multicenter retrospective study compared the short- and long-term surgical outcomes for patients with advanced MTC (T3 and T4 with or without nodal involvement) who underwent LC or OC between January 2008 and December 2019 using a propensity score-matched analysis.

Results: A total of 177 patients with advanced MTC were enrolled.

The effect of preoperative endoscopic tattooing using India ink on lymph node yield in laparoscopic colectomy for stage I right-sided colon cancer.

Purpose: The purpose of this study is to evaluate the effect of preoperative endoscopic tattooing using India ink (ETI) on the number of retrieved lymph nodes (LNs) dissected during laparoscopic surgery for stage I right-sided colon cancer (RCC).

Methods: This single-center, retrospective study included stage I RCC patients who underwent laparoscopic surgery between January 2010 and December 2021. The clinicopathological background and number of LNs retrieved were compared between patients managed with and without ETI.

The usefulness of indocyanine green fluorescence imaging for intestinal perfusion assessment of intracorporeal anastomosis in laparoscopic colon cancer surgery.

Purpose: The purpose of this study was to clarify the usefulness of indocyanine green fluorescence imaging (ICG-FI) in the assessment of intestinal vascular perfusion in patients who receive intracorporeal anastomosis (IA) in colon cancer surgery.

Methods: This was a single-center, retrospective study using propensity score matching. We compared the surgical outcomes of colon cancer patients who underwent laparoscopic colonic resection with IA or external anastomosis (EA) with the intraoperative evaluation of anastomotic perfusion using ICG-FI from January 2019 to July 2021.

Impact of Infectious Complications on Survival and Recurrence of Patients With Stage II/III Colorectal Cancer: A Multicenter Retrospective Study.

Background/aim: Postoperative complications are associated with increased recurrence in colorectal cancer (CRC). We investigated the impact of infectious complications on the recurrence of CRC and overall survival after curative surgery in a single study group.

Patients And Methods: In total, 1,668 patients who underwent radical resection for CRC in Yokohama City University, Yokohama Minami Kyosai Hospital, and Kanagawa Cancer Center between 2011 and 2019 were reviewed.

Chemotherapy-induced Reversion of Mutant to Wild-type in Metastatic Colorectal Cancer.

Background/aim: Secondary mutation of mutated RAS, induced by chemotherapy, is thought to be rare. However, introduction of liquid biopsy (LB) has made it possible to monitor RAS status in patients' plasma throughout the course of chemotherapy for metastatic colorectal cancer (mCRC), and disappearance of the RAS mutation (RAS-mt), i.e.

Laparoscopic extended right hemicolectomy versus laparoscopic transverse colectomy for mid-transverse colon cancer: a multicenter retrospective study from Kanagawa Yokohama Colorectal Cancer (KYCC) study group.

Purpose: The laparoscopic surgery approach for mid-transverse colon cancer (MTC) varies depending on tumor characteristics and the guidelines implemented by each surgeon; the optimal surgical procedure for MTC has not been established. This study aimed to compare the surgical outcomes of laparoscopic extended right hemicolectomy (Lap-ERHC) and laparoscopic transverse colectomy (Lap-TC) for MTC.

Methods: This was a multicenter, retrospective study.

Automated non-invasive identification of pelvic autonomic nerves with a handheld Raman spectrometer and potential application to nerve-sparing colorectal surgery: a preliminary study in surgical specimens.

Background: Although minimally invasive surgery for colorectal cancer, whether performed as standard laparoscopic or robotic surgery, has been established as an oncologically safe procedure, postoperative urinary dysfunction and sexual dysfunction remain matters of concern, even when so-called nerve-sparing surgery is performed. We have hypothesized that Raman spectroscopy can be used intraoperatively as a non-invasive label-free means of objective identification of the pelvic nerves, and we conducted a preliminary study by applying a newly developed handheld Raman spectrometer to surgical specimens.

Methods: Samples of nervous tissue, colon cancer tissue, and tissues from surrounding pelvic organs were obtained from 25 patients undergoing colectomy.

Prediction of lateral lymph node metastasis using OSNA method for mesorectal lymph nodes in low rectal cancer: A prospective study by the Kanagawa Yokohama Colorectal Cancer Study Group (KYCC1801).

Background And Objectives: Contrary to the Japanese guidelines recommendations regarding lateral lymph node dissection (LatLND) for rectal cancer, its omission is common in clinical practice without reliable omission criteria. Negative pathological mesorectal lymph node metastasis (MesLNM) is reportedly highly correlated with negative pathological lateral lymph node metastasis (p-LatLNM); however, this cannot be used as a criterion because pathological features are revealed postoperatively. Herein, we prospectively evaluated the negative predictive value (NPV) of MesLNM diagnosed via the one-step nucleic acid amplification (OSNA) method for p-LatLNM.

Impact of Intraoperative Blood Loss on the Survival of Patients With Stage II/III Colorectal Cancer: A Multicenter Retrospective Study.

Background: Resection of the primary lesion with radical lymph node dissection is the most promising treatment avenue for patients with cancer. On the other hand, these procedures often induce excessive intraoperative blood loss (IBL) and require perioperative blood transfusion. The influence of IBL on the long-term postoperative outcomes of patients with digestive cancer is controversial.

Preoperative Pre-albumin Concentration as a Predictor of Short-term Outcomes in Elderly Patients With Colorectal Cancer.

Background/aim: Population aging results in increasing numbers of elderly persons undergoing surgery for colorectal cancer. We sought to identify objective preoperative indicators of outcomes, with a view toward development of safe, effective treatments for such patients.

Patients And Methods: The study included 99 patients aged 80 years or more, who were treated surgically for stage I- III colorectal cancer.

Can D3 Lymph Node Dissection for Patients With Colon Cancer With a Poor C-Reactive Protein/Albumin Ratio Improve Survival Outcomes?

Aim: D3 lymph node dissection (LND) for stage II and III colon cancer has been shown to improve prognosis, however, it generally increases surgical stress. Studies have reported that the C-reactive protein/albumin ratio (CAR) may be a useful inflammatory-nutritional biomarker to predict postoperative complications and poor prognosis for with various types of cancer. Our purposes were to assess the short- and long-term outcomes of D3 LND in patients with a high preoperative CAR (≥ 0.

Potential Benefits of Minimally Invasive Laparoscopy in Reducing Local Recurrence After Surgery for Low Rectal Cancer.

Aim: To compare the mid-term oncological results between patients with low rectal cancer who underwent minimally invasive laparoscopic surgery (MILS) and those who underwent open surgery (OS).

Patients And Methods: Overall, 262 matched patients who underwent primary resection for low rectal cancer between 2000 and 2019 were divided into MILS (n=131; n=107, conventional laparoscopic surgery; n=24, robotic surgery) and OS (n=131) groups. The short- and mid-term outcomes were compared.

Prognostic impact of tumour sidedness in patients with stage II colon cancer: a single-centre retrospective study.

Background: The search for high-risk factors in stage II colon cancer (CC) is ongoing and several high-risk factors for stage II CC have been identified; however, the effects of tumour sidedness on prognosis are not clear. This study aims to determine whether tumour sidedness could be identified as another high-risk factor for stage II CC.

Methods: We retrospectively analysed 189 patients with stage II CC and compared clinicopathological findings and long-term outcomes between the patients with right colonic cancer (RCC) and with left colonic cancer (LCC).

Rectal Cancer Surgery in Patients Older Than 80 Years: Is Hartmann's Procedure Safe?

Background/aim: The current study aimed to identify the safety and efficacy of Hartmann's procedure (HP) among elderly patients (age ≥80 years) with rectal cancer.

Patients And Methods: Data on surgical outcome, survival rate, and incidence of stoma reversal were retrospectively compared between patients aged over 80 years who underwent anterior resection (AR) and HP.

Results: In total, 79 elderly patients underwent rectal cancer surgery.

Additional Surgical Resection After Endoscopic Resection for Patients With High-risk T1 Colorectal Cancer.

Background/aim: The purpose of this study was to reveal the safety and efficacy of additional surgical resection (ASR) for high-risk T1 colorectal cancer (CRC) after endoscopic resection (ER).

Patients And Methods: We retrospectively analyzed 191 patients with high-risk T1 CRC after ER.

Results: The ASR was performed in 176 (92.