Superiority trial for the development of an ideal method for the closure of midline abdominal wall incisions to reduce the incidence of wound complications after elective gastroenterological surgery: study protocol for a randomized controlled trial

BACKGROUND

The recent guidelines from the European and American Hernia Societies recommend a continuous small-bite suturing technique with slowly absorbable sutures for fascial closure of midline abdominal wall incisions to reduce the incidence of wound complications, especially for incisional hernia. However, this is based on low-certainty evidence. We could not find any recommendations for skin closure. The wound closure technique is an important determinant of the risk of wound complications, and a comprehensive approach to prevent wound complications should be developed.

METHODS

We propose a single-institute, prospective, randomized, blinded-endpoint trial to assess the superiority of the combination of continuous suturing of the fascia without peritoneal closure and continuous suturing of the subcuticular tissue (study group) over that of interrupted suturing of the fascia together with the peritoneum and interrupted suturing of the subcuticular tissue (control group) for reducing the incidence of midline abdominal wall incision wound complications after elective gastroenterological surgery with a clean-contaminated wound. Permuted-block randomization with an allocation ratio of 1:1 and blocking will be used. We hypothesize that the study group will show a 50% reduction in the incidence of wound complications. The target number of cases is set at 284. The primary outcome is the incidence of wound complications, including incisional surgical site infection, hemorrhage, seroma, wound dehiscence within 30 days after surgery, and incisional hernia at approximately 1 year after surgery.

DISCUSSION

This trial will provide initial evidence on the ideal combination of fascial and skin closure for midline abdominal wall incision to reduce the incidence of overall postoperative wound complications after gastroenterological surgery with a clean-contaminated wound. This trial is expected to generate high-quality evidence that supports the current guidelines for the closure of abdominal wall incisions from the European and American Hernia Societies and to contribute to their next updates.

TRIAL REGISTRATION

UMIN-CTR UMIN000048442. Registered on 1 August 2022. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055205.

Risk of metachronous colorectal cancer after surgical resection of index rectal cancer in Lynch syndrome: a multicenter retrospective study in Japan

PURPOSE

This study evaluated the risk of metachronous colorectal cancer (CRC) after resection of index (first) rectal cancer in patients with Lynch syndrome (LS).

METHODS

Clinicopathological data of patients with genetically proven LS were retrospectively analyzed in this multicenter Japanese study. The cumulative incidence of metachronous CRC and the overall survival were compared between patients with index rectal cancer (rectal group) and those with index colon cancer (colon group).

RESULTS

The median age at index CRC surgery was lower in the rectal group than in the colon group (37 vs. 46 years old, P = 0.01). The cumulative 5-, 10-, and 20-year incidences of metachronous CRC were 3.5%, 13.9%, and 21.1%, respectively, in the rectal cancer group and 14.9%, 22.0%, and 57.9%, respectively, in the colon cancer group (P = 0.02). The overall survival curves were not significantly different between two groups (P = 0.23).

CONCLUSION

This is the first report from an East Asian country to report the risk of metachronous CRC after resection of index rectal cancer in patients with LS. Despite this study having several limitations, we cannot recommend extended resection, such as total proctocolectomy, for index rectal cancer as a standard surgical treatment in patients with LS.

Risk of gastric adenoma and adenocarcinoma in patients with familial adenomatous polyposis in Japan: a nationwide multicenter study

BACKGROUND

Patients with familial adenomatous polyposis (FAP) have an increased risk of developing gastric neoplasms. However, the clinical course of FAP with these gastric lesions has not yet been fully clarified. The present study aimed to clarify the changes in the incidence risk of developing gastric adenoma or gastric cancer during the lifespan of patients with FAP.

METHODS

Four hundred forty-three patients with data regarding gastric adenoma and gastric cancer retrospectively registered in a nationwide Japanese multicenter study were enrolled. The cumulative incidences and hazard rates (HRs) of gastric neoplasms were evaluated.

RESULTS

The cumulative incidence rates in 50-year-old patients with FAP were 22.8% for gastric adenoma and 7.6% for gastric cancer, respectively. No significant association was found between gastric neoplasms and the colonic phenotype. The peak age for the HR of gastric adenoma was 65 years, with the highest HR (0.043). Regarding the incidence of gastric cancer, the HR increased moderately up to the age of 40 years, but the increase accelerated from the age of 50 years (HR = 0.0067).

CONCLUSION

Careful surveillance of the upper gastrointestinal tract in elderly patients with FAP, such as shortening the interval of follow-up according to age, may be helpful for early diagnosis of gastric cancer.

Clinical features and distribution of the APC variant in duodenal and ampullary polyps in patients with familial adenomatous polyposis: a multicenter retrospective cohort study in Japan

BACKGROUND

Management of duodenal or ampullary adenomas in patients with familial adenomatous polyposis (FAP) is a major challenge for clinicians. Insufficient data are available to evaluate the clinical manifestations and distribution of adenomatous polyposis coli (APC) variants in these patients.

METHODS

We enrolled 451 patients with data regarding duodenal or ampullary polyps from 632 patients with FAP retrospectively registered in a nationwide Japanese multicenter study. Clinicopathological features and distribution of APC variants were compared between patients with and without duodenal or ampullary polyps.

RESULTS

Duodenal and ampullary polyps were found in 59% and 18% of patients with FAP, respectively. The incidence of duodenal cancer was 4.7% in patients with duodenal polyps, and that of ampullary cancer was 18% in patients with ampullary polyps. Duodenal polyps were significantly associated with the presence of ampullary polyps and jejunal/ileal polyps. Duodenal polyps progressed in 35% of patients with a median follow-up of 776 days, mostly in those with early Spigelman stage lesions. Ampullary polyps progressed in 50% of patients with a follow-up of 1484 days. However, only one patient developed a malignancy. The proportion of patients with duodenal polyps was significantly higher among those with intermediate- or profuse-type APC variants than attenuated-type APC variants. The presence of duodenal polyps was significantly associated with ampullary and jejunal/ileal polyps in patients with intermediate- or profuse-type APC variants.

CONCLUSIONS

Periodic endoscopic surveillance of the papilla of Vater and small intestine should be planned for patients with FAP with duodenal polyps.

Risk of metachronous colorectal cancer after colectomy for first colon cancer in Lynch syndrome: multicenter retrospective study in Japan

BACKGROUND

We evaluated the risk of metachronous colorectal cancer (mCRC) and explored the optimal extent of colectomy in patients with Lynch syndrome (LS) and first colon cancer (fCC) in Japan, where the extent of colectomy for colon cancer (CC) is shorter than that in Western countries.

METHODS

The clinicopathologic and survival data of patients with LS who developed CC were collected from a nationwide database and analyzed retrospectively. The cumulative incidence of mCRC after actual segmental colectomy was compared with that of mCRC when more extensive colectomy was assumed.

RESULTS

There were 142 eligible patients (65 female). The median age at fCC surgery was 46.5 (range: 14-80) years. The cumulative incidence of 5-, 10-, and 20-year mCRC rate was 13.4%, 20.8%, and 53.6%, respectively. The incidence was higher in the left-sided group (splenic flexure to rectosigmoid colon, n = 54) than in the right-sided group (cecum to transvers colon, n = 88) (66.3% vs. 45.3% in 20 years, P < 0.01). Assuming that all patients would have undergone hemicolectomy or total colectomy, the estimated mCRC risk was 41.5% and 9.4% (P < 0.01, vs. actual procedures), respectively. The 20-year overall survival rate of all the patients was 83.3% without difference by fCC sidedness (P = 0.38).

CONCLUSIONS

To reduce the incidence of mCRC, patients with genetically diagnosed LS and fCC, preferentially located in the left-sided colon, may need to undergo more extended colectomy than that usually performed in Japan. However, such extended colectomy should be counterbalanced with favorable overall survival and actual risk of mCRC development.

A postoperative body weight increase is a novel risk factor for incisional hernia of midline abdominal incision after elective gastroenterological surgery

PURPOSE

Midline abdominal incisions (MAIs) are widely used in both open and minimally invasive surgery. Incisional hernia (IH) accounts for most long-term postoperative wound complications. This study explored the risk factors for IH due to MAI in patients with clean-contaminated wounds after elective gastroenterological surgery.

METHODS

The present study targeted patients enrolled in 2 randomized controlled trials to evaluate the efficacy of intraoperative interventions for incisional SSI prevention after gastroenterological surgery for clean-contaminated wounds. The patients were reassessed, and pre- and intraoperative variables and postoperative outcomes were collected. IH was defined as any abdominal wall gap, regardless of bulge, in the area of a postoperative scar that was perceptible or palpable on clinical examination or computed tomography according to the European Hernia Society guidelines. The risk factors for IH were identified using univariate and multivariate analyses.

RESULTS

The study population included 1,281 patients, of whom 273 (21.3%) developed IH. Seventy-four (5.8%) patients developed incisional SSI. Multivariate logistic regression analysis revealed that female sex (odds ratio [OR], 1.39; 95% confidence interval [CI] 1.03-1.86, p = 0.031), high preoperative body mass index (OR, 1.81; 95% CI 1.19-2.77, p = 0.006), incisional SSI (OR, 2.29; 95% CI 1.34-3.93, p = 0.003), and postoperative body weight increase (OR, 1.49; 95% CI 1.09-2.04, p = 0.012) were independent risk factors for IH due to MAI in patients who underwent elective gastroenterological surgery.

CONCLUSION

We identified postoperative body weight increase at one year as a novel risk factor for IH in patients with MAI after elective gastroenterological surgery.

Computer-aided diagnosis of early-stage colorectal cancer using nonmagnified endoscopic white-light images (with videos)

BACKGROUND AND AIMS

Differentiation of colorectal cancers (CRCs) with deep submucosal invasion (T1b) from CRCs with superficial invasion (T1a) or no invasion (Tis) is not straightforward. This study aimed to develop a computer-aided diagnosis (CADx) system to establish the diagnosis of early-stage cancers using nonmagnified endoscopic white-light images alone.

METHODS

From 5108 images, 1513 lesions (Tis, 1074; T1a, 145; T1b, 294) were collected from 1470 patients at 10 academic hospitals and assigned to training and testing datasets (3:1). The ResNet-50 network was used as the backbone to extract features from images. Oversampling and focal loss were used to compensate class imbalance of the invasive stage. Diagnostic performance was assessed using the testing dataset including 403 CRCs with 1392 images. Two experts and 2 trainees read the identical testing dataset.

RESULTS

At a 90% cutoff for the per-lesion score, CADx showed the highest specificity of 94.4% (95% confidence interval [CI], 91.3-96.6), with 59.8% (95% CI, 48.3-70.4) sensitivity and 87.3% (95% CI, 83.7-90.4) accuracy. The area under the characteristic curve was 85.1% (95% CI, 79.9-90.4) for CADx, 88.2% (95% CI, 83.7-92.8) for expert 1, 85.9% (95% CI, 80.9-90.9) for expert 2, 77.0% (95% CI, 71.5-82.4) for trainee 1 (vs CADx; P = .0076), and 66.2% (95% CI, 60.6-71.9) for trainee 2 (P < .0001). The function was also confirmed on 9 short videos.

CONCLUSIONS

A CADx system developed with endoscopic white-light images showed excellent per-lesion specificity and accuracy for T1b lesion diagnosis, equivalent to experts and superior to trainees. (Clinical trial registration number: UMIN000037053.).

Update of risk factors for surgical site infection in clean-contaminated wounds after gastroenterological surgery: An analysis of 1,878 participants enrolled in 2 recent randomized control trials for the prevention of surgical site infection

BACKGROUND

Clean-contaminated wounds should be the main target for reducing the burden of harm caused by surgical site infection after gastroenterological surgery.

METHODS

The present study targeted 1,973 patients enrolled in 2 randomized controlled trials to evaluate the efficacy of intraoperative interventions for incisional surgical site infection prevention after gastroenterological surgery with clean-contaminated wounds. Patients were reassessed, and preoperative and postoperative variables were collected. Risk factors for surgical site infection were identified by univariate and multivariate analyses.

RESULTS

The study population included 1,878 patients, among whom 213 (11.3%) developed overall surgical site infection and 119 (6.3%) developed incisional surgical site infection. A multivariate analysis revealed that steroid or immunosuppressant use (odds ratio 3.03; 95% confidence interval 1.37-6.73, P = .0064), open surgery (odds ratio 1.77; 95% confidence interval 1.11-2.83, P = .0167), and long operative time (odds ratio 2.31; 95% confidence interval 1.5-3.56, P < .001) were independent risk factors for incisional surgical site infection. Steroid or immunosuppressant use (odds ratio 2.62; 95% confidence interval 1.29-5.33, P = .0078), open surgery (odds ratio 2.13; 95% confidence interval 1.44-3.16, P < .001), and long operative time (odds ratio 2.92; 95% confidence interval 2.08-4.10, P < .001) were also independent risk factors for overall surgical site infection in the multivariate analysis. Furthermore, a multivariate analysis revealed that a long operative time (odds ratio 3.21; 95% confidence interval 1.69-6.1, P = .00378) was an independent risk factor for incisional surgical site infection in patients who underwent laparoscopic surgery.

CONCLUSION

Even under current measures for surgical site infection prevention, surgeons should continue to make efforts to appropriately expand the indication of laparoscopic surgery and to reduce operative times even when performing laparoscopic surgery.

Aqueous Povidone-Iodine Versus Normal Saline For Intraoperative Wound Irrigation on The Incidence of Surgical Site Infection in Clean-Contaminated Wounds After Gastroenterological Surgery: A Single-Institute, Prospective, Blinded-Endpoint, Randomized Controlled Trial

OBJECTIVE

This trial evaluated the superiority of intraoperative wound irrigation (IOWI) with aqueous povidone-iodine (PVP-I) compared with that with saline for reducing the incidence of surgical site infection (SSI).

BACKGROUND

IOWI with aqueous PVP-I is recommended for the prevention of SSI by the World Health Organization and the Centers for Disease Control and Prevention, although the evidence level is low.

METHODS

This single institute in Japan, prospective, randomized, blinded-endpoint trial was conducted to assess the superiority of IOWI with aqueous PVP-I in comparison with IOWI with saline for reducing the incidence of SSI in clean-contaminated wounds after gastroenterological surgery. Patients 20 years or older were assessed for eligibility, and the eligible participants were randomized at a 1:1 ratio using a computer-generated block randomization. In the study group, IOWI was performed for 1 minute with 40 mL of aqueous 10% PVP-I before skin closure. In the control group, the procedure was performed with 100 mL of saline. Participants, assessors, and analysts were masked to the treatment allocation. The primary outcome was the incidence of incisional SSI in the intention-to-treat set.

RESULTS

Between June 2019 and March 2022, 941 patients were randomized to the study group (473 patients) or the control group (468 patients). The incidence of incisional SSI was 7.6% in the study group and 5.1% in the control group (risk difference 0.025, 95% CI -0.006 to 0.056; risk ratio 1.484, 95% CI 0.9 to 2.448; P =0.154).

CONCLUSION

The current recommendation of IOWI with aqueous PVP-I should be reconsidered.

Current practice of colonoscopy surveillance in patients with lynch syndrome: A multicenter retrospective cohort study in Japan

Objectives

Colonoscopy surveillance reduces the incidence of colorectal cancer through the detection and endoscopic removal of adenomas. Current guidelines recommend that patients with Lynch syndrome should have colonoscopy surveillance every 1–2 years starting at the age of 20–25. However, insufficient data are available to evaluate the quality and safety of colonoscopy surveillance for patients with Lynch syndrome nationwide in Japan.

Methods

Patients with Lynch syndrome (n = 309) from 13 institutions who underwent one or more colonoscopy procedures were enrolled in this retrospective analysis. Colonoscopy completion rate, colonoscopy‐related complication rate, proportion with an adequate colonoscopy interval, and adenoma detection rate were reviewed.

Results

The colonoscopy completion rate was 98.8% and a history of previous colorectal cancer surgery was significantly associated with a higher completion rate. All complications were associated with endoscopic treatment and the rate of bleeding needing hemostasis and perforation needing surgical repair were both 0.16% after colonoscopy with polypectomy. The adenoma detection rate at the first colonoscopy was 25%. Although there was no difference in the completion and complication rates based on differences in the colonoscopy experience of the endoscopist, the detection rate of adenomas and intramucosal cancers was significantly higher with more experienced endoscopists. The proportion of patients developing cancer was significantly higher with a >24 months than a ≤24 months interval.

Conclusion

High‐volume experienced endoscopists and appropriate surveillance intervals may minimize the risk of developing colorectal cancers in patients with Lynch syndrome.

Mid-term Efficacy of Local Repair Using Modified Altemeier Technique for Stomal Prolapse: A Case Series

Introduction: Stomal prolapse (SP) is characterized by full-thickness protrusion of the bowel through the stoma site. The surgical procedures for SP include local repair, abdominal wall fixation, and stoma relocation. However, previous reports were mostly case reports or case series with a small number of patients and lacked long-term results. A modified Altemeier technique (MAT) has been used for the local repair of SP in our institution, and this study aimed to evaluate its mid-term efficacy.

Methods: We reviewed patients who underwent MAT for SP between August 2013 and December 2020. The variables included patient characteristics, type of stoma, indications of stoma creation, the time interval from stoma creation to prolapse, site of prolapse, reasons for SP surgery, perioperative variables, complications during SP surgery, and length of follow-up. Recurrence of SP was defined as the need for change in stoma care or re-protrusion of the stoma by more than 5 cm in length.

Results: Ten patients were included in this study. The median age at the time of SP surgery was 71.5 years. The indications of stoma creation included unresectable or recurrent intra-abdominal malignancies in four patients, diverting ileostomy with rectal cancer surgery in two, transverse colon cancer in one, gastric and rectal cancer in one, rectovaginal fistula in one, and non-occlusive mesenteric ischemia in one. The median interval from stoma creation to prolapse was 2.5 months. Six patients underwent elective SP surgery, and four patients underwent emergency surgery for incarcerated prolapse. The median operative time was 75.5 min. Postoperative complications that included transient mucosal ischemia and subcutaneous abscess occurred in one patient. There were four recurrences (40%), and the median time interval from surgery to recurrence was 4.5 months. Two patients underwent repeated MAT, one of whom underwent stomal reversal with laparotomy for re-recurrence. The median follow-up duration was 19 months.

Conclusion: MAT for SP is associated with a high recurrence rate in mid-term follow-up.

Anal fistula metastasis of rectal cancer after neoadjuvant therapy: a case report

BACKGROUND

Anal metastasis of colorectal cancer is very rare and may present synchronously or metachronously, regardless of pre-existing anal diseases. We report a case of anal fistula metastasis after completion of neoadjuvant therapy for rectal cancer, followed by surgical resection of the primary tumor and metastatic lesion.

CASE PRESENTATION

A 50-year-old man was diagnosed with rectal cancer located 5 cm from the anal verge, with a clinical stage of cT3N0M0. He denied any medical or surgical history, and physical examination revealed no perianal disease. He underwent preoperative chemoradiation therapy (CRT) consisting of a tegafur/gimeracil/oteracil potassium (S-1)-based regimen with 45 Gy of radiation. After completion of CRT, computed tomography (CT) revealed the primary tumor's partial response, but a liver mass highly suggestive of metastasis was detected. This mass was later diagnosed as cavernous hemangioma 3 months after CRT initiation. He then underwent and completed six cycles of consolidation chemotherapy with a capecitabine-based regimen. Subsequent colonoscopy revealed the complete response of the primary tumor, but CT showed thickening of the edematous rectal wall. Therefore, we planned to perform low anterior resection as a radical surgery. However, he presented with persistent anal pain after the last chemotherapy, and magnetic resonance imaging revealed a high-intensity mass behind the anus, suggestive of an anal fistula. We considered the differential diagnosis of a benign anal fistula or implantation metastasis into the anal fistula. Fistulectomy was performed, and a pathological diagnosis of tubular adenocarcinoma, suggestive of implantation metastasis, was made. Thereafter, we performed laparoscopic abdominoperineal resection. Histopathological examination revealed well-differentiated adenocarcinoma, ypT2N0, with a grade 2 therapeutic effect. Subsequent immunohistochemistry of the resected anal fistula showed a CDX-2-positive, CK20-positive, CK7-negative, and GCDFP-15 negative tumor, with implantation metastasis. There was no cancer recurrence 21 months after the radical surgery.

CONCLUSIONS

This is the first report of anal fistula metastasis after neoadjuvant therapy for rectal cancer in a patient without a previous history of anal disease. If an anal fistula is suspected during or after neoadjuvant therapy, physical and radiological assessment, differential diagnosis, and surgical intervention timing for fistula must be carefully discussed.

Impact of sarcopenia on surgical and oncologic outcomes of laparoscopic surgery for colorectal cancer

BACKGROUND

The study aimed to evaluate the impact of sarcopenia on short- and long-term outcomes for laparoscopic colorectal cancer surgery.

METHODS

Study participants were 209 patients who underwent laparoscopic surgery for any stage of colorectal cancer between 2016 and 2017. Skeletal muscle indices were calculated with preoperative computed tomography. Patients were divided into sarcopenic and non-sarcopenic groups based on index cut-off values and variables were compared.

RESULTS

The prevalence of sarcopenia was 41.1%. Sarcopenic patients experienced shorter operative times and a lower incidence of surgical site infections; however, the incidence of severe postoperative complications and readmission were increased for this group. Although the 3-year disease-free survival rate was not statistically different between groups, sarcopenic patients had a significantly worse 3-year overall survival rate compared with than the non-sarcopenic group.

CONCLUSION

Sarcopenia has both favorable and unfavorable effects on patients who underwent laparoscopic colorectal cancer surgery.

Superiority trial comparing intraoperative wound irrigation with aqueous 10% povidone-iodine to saline for the purpose of reducing surgical site infection after elective gastrointestinal surgery: study protocol for a randomised controlled trial

INTRODUCTION

Surgical site infection (SSI) is one of the most common complications after gastrointestinal surgery, with a reported incidence of approximately 10%-25%, which is higher than the rates after other types of surgery. Intraoperative wound irrigation (IOWI) is a simple intervention for SSI prevention, and recent studies have reported that IOWI with aqueous povidone-iodine (PVP-I) is significantly more effective at reducing the incidence of SSI than saline. However, the evidence level of previous trials evaluating the efficacy of aqueous PVP-I solution for preventing SSI has been low.

METHODS AND ANALYSES

We propose a single-institute, prospective, randomised, blinded-endpoint trial to assess the superiority of IOWI with aqueous 10% PVP-I solution compared with normal saline for reducing SSI in clean-contaminated wounds after elective gastrointestinal surgery. In the study group, IOWI with 40 mL of aqueous 10% PVP-I solution is performed for 1 min before skin suture, and in the control group, IOWI with 100 mL of saline is performed for 1 min before skin suture. We hypothesise that IOWI with aqueous 10% PVP-I solution will achieve a 50% reduction in the incidence of SSIs. The target number of cases is set at 950. The primary outcome is the incidence of incisional SSI up to postoperative day 30 and will be analysed in the modified intention-to-treat set.

ETHICS AND DISSEMINATION

This trial was designed and is being conducted by Saitama Medical Center, Jichi Medical University, with approval from the Bioethics Committee for Clinical Research, Saitama Medical Center, Jichi Medical University. Participant recruitment began in June 2019. The final results will be reported in international peer-reviewed journals immediately after trial completion.

TRIAL REGISTRATION NUMBER

UMIN000036889.

Effect of Antithrombotic Therapy on Secondary Bleeding After Proctological Surgery

Introduction

Surgery for patients taking antithrombotic drugs for the prevention and treatment of cardiovascular disease, including anticoagulants and antiplatelet drugs, is increasing because of the aging society. In patients with moderate to high risk for cardiovascular events, receiving antiplatelet therapy, and requiring noncardiac surgery continuing antiplatelet drugs perioperatively is recommended. To date, there have been limited reports on the risk of secondary bleeding after proctological surgery in patients who are administered antithrombotic drugs. The purpose of this study was to identify the incidence and severity of secondary bleeding after proctological surgery for patients with or without antithrombotic therapy.

Methods

We retrospectively identified 113 patients who underwent proctological surgery in our hospital from March 2009 to February 2019. In general, antiplatelet drugs were continued and anticoagulant drugs were either substituted or withdrawn prior to surgery. The severity of secondary bleeding was classified as mild, moderate, or severe.

Results

Eighteen patients underwent antithrombotic therapy (A group) and 95 patients did not undergo antithrombotic therapy (N group). Secondary bleeding was observed in nine patients (8.0%) and patients in the A group exhibited a significantly higher rate of secondary bleeding than those in the N group (39% vs. 2.4%, P < 0.01). The median interval from surgery to the onset of secondary bleeding was five days (range: 0-11). The severity of bleeding was the highest in patients administered direct oral anticoagulants (DOAC) and was the lowest in those administered aspirin. There was no mortality or cardiovascular event.

Conclusion

Antithrombotic therapy carries a high risk of secondary bleeding after proctological surgery. Delaying the postoperative resumption of anticoagulants is considered while balancing the risk of postoperative thromboembolic complications against secondary bleeding.

Risk factors and management of stoma-related obstruction after laparoscopic colorectal surgery with diverting ileostomy

BACKGROUND

Stoma-related obstruction (SRO) is defined as small bowel obstruction occurring around the limbs of diverting ileostomy (DI). This study was aimed to investigate the incidence, risk factors, and management of SRO after laparoscopic colorectal surgery with DI creation.

METHODS

This study included 155 patients who underwent laparoscopic colorectal surgery with DI creation for rectal cancer (n = 138), ulcerative colitis (UC) (n = 14), and familial adenomatous polyposis (FAP) (n = 3) between 2011 and 2019. Univariate and multivariate analyses were performed to identify the risk factors of SRO.

RESULTS

The incidence of SRO was 7.7% (n = 12), and it was significantly lower (P < 0.01) in patients with lower anterior resection or intersphincteric resection (4.3%) than in those with ileal-pouch anal anastomosis (IPAA) (35.2%). The multivariate analysis revealed that IPAA was independently associated with the development of SRO (P = 0.001; odds ratio, 9.4; 95% confidence interval, 2.5-35.4). Eleven of 12 patients (92%) with SRO required trans-stomal tube decompression, and 8 of those (67%) underwent early stoma closure.

CONCLUSION

IPAA was an independent risk factor of SRO in laparoscopic colorectal surgery with DI creation. Early stoma closure was needed in most cases of SRO.

Tolerability and Adverse Events of Adjuvant Chemotherapy for Rectal Cancer in Patients With Diverting Ileostomy

BACKGROUND/AIM

The impact of diverting ileostomy on the feasibility of adjuvant chemotherapy (ACT) remains unclear. We retrospectively investigated the tolerability and adverse events of ACT for rectal cancer in patients with diverting ileostomy.

PATIENTS AND METHODS

Thirty-three patients who received ACT after curative resection with ileostomy construction for rectal cancer were analyzed. We assessed completion rate, the mean relative dose intensities, and the factors affecting the tolerability of ACT.

RESULTS

The completion rate of each chemotherapy regimen was 10 out of 16 patients in oral uracil-tegafur plus leucovorin (UFT/LV), 1 out of 3 patients in oral capecitabine (Capecitabine) and 2 out of 14 patients in capecitabine plus oxaliplatin (CAPOX). The mean relative dose intensities were 77% in UFT/LV, 48% in Capecitabine, and 57% of capecitabine and 42% of oxaliplatin in CAPOX. In multivariate analysis, laparoscopic surgery (Odds ratio=11.6, p=0.021) and receiving preoperative chemoradiotherapy (Odds ratio=32.4, p=0.021) were associated with treatment completion.

CONCLUSION

Completion rate of ACT in patients with diverting ileostomy was lower than that of colorectal cancer patients in the previous studies. UFT/LV may be a more tolerable regimen than Capecitabine or CAPOX in colorectal cancer patients with diverting ileostomy.

Intra-abdominal desmoid tumor after laparoscopic low anterior resection for rectal cancer: A case report

Desmoid tumors are monoclonal fibroblastic proliferations arising from soft tissue classified as intra-abdominal, extra-abdominal and abdominal wall types. We present a patient with an intra-abdominal desmoid tumor diagnosed 20 months after laparoscopic resection of rectal cancer. A 70-year-old woman with hematochezia was diagnosed with advanced rectal cancer. Preoperative chemoradiotherapy followed by laparoscopic low anterior resection was performed. During follow-up, a nodular soft-tissue density measuring 28 mm was detected in the presacral region. Metastasis from rectal cancer was diagnosed and four courses of chemotherapy were given, including capecitabine, oxaliplatin and bevacizumab. Computed tomography scan showed that the mass slightly decreased in size and surgical resection was performed. Histopathological examination revealed a proliferation of spindle-shaped cells and collagenous stroma diagnosed as a desmoid tumor. This report highlights the possibility of a desmoid tumor in the differential diagnosis of an intra-abdominal mass found during follow-up after resection of colorectal cancer including following laparoscopic resection.

Idiopathic mesenteric phlebosclerosis treated with laparoscopic subtotal colectomy: A case report

Idiopathic mesenteric phlebosclerosis is a rare entity characterized by chronic intestinal ischemia due to calcification and obstruction of the mesenteric veins. Here, we report a patient with idiopathic mesenteric phlebosclerosis treated with laparoscopic subtotal colectomy after evaluation by imaging studies. The patient was a 68-year-old Japanese woman with recurrent abdominal pain who had taken a Chinese herbal medicine for more than 20 years. Abdominal CT showed wall thickening of the right colon with calcification of branches of the superior mesenteric vein. Colonoscopy showed cyanotic mucosa from the cecum to the sigmoid colon. The affected area seen on colonoscopy extended to the distal colon. Despite discontinuation of the herbal medicine, her symptoms did not improve. Laparoscopic subtotal colectomy was performed. This report highlights the importance of appropriately evaluating the extent of the affected preoperatively area based on findings from colonoscopy, CT, and contrast enema.

Current Management of Intestinal Stomas and Their Complications

Inappropriate stoma site, improper management of stoma, and stoma complications lead to diminished quality of life of ostomates. Healthcare professionals involved in stoma creation and/or care should have the fundamental and updated knowledge of the management of stomas and their complications. This review article consists of the following major sections: principles of perioperative patient management, early complications, and late complications. In the “principles of perioperative patient management” section, the current concepts and trends in preoperative education, stoma site marking, postoperative education, and patient educational resources are discussed. In the “early complications” section, we have focused on the etiology and current management of ischemia/necrosis, fluid and electrolyte imbalances, mucocutaneous separation, and retraction. In the “late complications” section, we have focused on the etiology and current management of parastomal hernia, stoma prolapse, parastomal varices, and pyoderma gangrenosum. Pre- and postoperative patient education facilitates the patient's independence in stoma care and resumption of normal activities. Healthcare providers should have basic skills and updated knowledge on the management of stomas and complications of stomas, to act as the first crisis manager for ostomates.

Temporary loss of consciousness during cetuximab treatment of a patient with metastatic colon cancer: a case report

BACKGROUND

Anti-epidermal growth factor receptor (EGFR) antibody is widely used for the treatment of patients with metastatic colorectal cancer. Hypomagnesemia is a comparatively frequent adverse event of this drug, which is likely overlooked because it occurs later in treatment without symptoms. Furthermore, hypomagnesemia and hypomagnesemia-induced corrected QT (QTc) prolongation may lead to loss of consciousness (LOC), the onset of which is not generally considered associated with the treatment of anti-EGFR antibody because of its rare occurrence. Here, we present a colorectal cancer patient treated with anti-EGFR antibody, who suffered LOC during treatment while severe hypomagnesemia or QTc prolongation was not observed.

CASE PRESENTATION

A 69-year-old man with metastatic colon cancer was treated with cetuximab (anti-EGFR antibody) plus irinotecan as third-line chemotherapy. His serum magnesium level gradually decreased, and grade 2 hypomagnesemia (a serum magnesium level of 0.9 mg/dL) was observed at the 12th administration of cetuximab. In light of this development, intravenous supplementation of 20 mEq magnesium sulfate began with careful blood monitoring despite the lack of clinical symptoms. Electrocardiogram (ECG) showed prolonged QT or corrected QT (QTc) intervals (grade 1). His serum magnesium level remained at 0.9 mg/dL, and no hypomagnesemia symptoms were observed by the 17th administration of cetuximab. After the treatment, however, he suddenly lost consciousness without symptoms related to infusion or allergic reactions. Circulatory collapse following dermatological reactions and respiratory events were not evident. Intravenous supplementation of magnesium sulfate was administered again. He awakened 2 min after the onset of temporary LOC without any other symptoms related to hypomagnesemia, such as lethargy, tremor, tetany, and seizures. No other etiology outside of the low level of serum magnesium was confirmed in further examinations. Cetuximab was discontinued, and his serum magnesium level returned to a level within the normal range after 6 weeks. Because of tumor progression, regorafenib and TAS-102 (trifluridine tipiracil hydrochloride) were introduced sequentially for 6 months. Five months after the final treatment of TAS-102, he died of his primary disease, which reflected a survival period of 4 years and 6 months since the beginning of treatment.

CONCLUSIONS

This case report reminds clinicians that LOC can be induced without severe hypomagnesemia or QTc prolongation, during anti-EGFR antibody treatment for metastatic colorectal cancer even while under carefully monitored magnesium supplementation.

Delayed hemorrhage after cold and hot snare resection of colorectal polyps: a multicenter randomized trial (interim analysis)

Background and study aims  Delayed bleeding is believed to occur less frequently after cold snare polypectomy (CSP), but this has not been validated in clinical trials. This study aimed to compare rates of delayed bleeding after CSP and hot snare polypectomy (HSP). Patients and methods  We conducted a multicenter, randomized controlled trial. Participants scheduled to undergo endoscopic resection of colorectal polyps ≤ 10 mm were enrolled and randomly assigned to CSP or HSP. Prophylactic clipping was performed at the endoscopists' discretion. The primary outcome was delayed bleeding rate. Secondary outcomes included immediate bleeding rate and clipping rate. Sample size calculation showed that 451 patients were required in each arm. Results  At the end of the study period decided in advance, 308 participants were recruited and an interim analysis was performed. A total of 273 patients (mean age 62.2 ± 8.8 years; 188 males) were analyzed, with 139 patients allocated to CSP and 134 to HSP. In total, 367 polyps were resected with CSP and 360 polyps with HSP. There were no significant differences in patient demographics or polyp characteristics. In per-patient-based analysis, delayed bleeding rates were 0.7 % after CSP and 0.7 % after HSP. Per-polyp analysis showed similar results (CSP: 0.3 % vs. HSP: 0.6 %). The immediate bleeding rate was significantly higher with CSP vs. HSP (54 % vs.14 %, P  < 0.0001), while clipping rates were 18 % and 19 %, respectively. Conclusion  This interim analysis did not demonstrate that delayed bleeding after CSP is less frequent than after HSP. The delayed bleeding rate after HSP was lower than expected. Meeting presentations: Digestive Disease Week 2017.

Significance of monitoring plasma vascular endothelial growth factor signals during treatment of colorectal cancer patients

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Background: Vascular endothelial growth factor (VEGF) signals may change during colorectal cancer (CRC) treatment, but monitoring real time changes has not been conducted. Methods: Blood monitoring was carried out to track changes in the status of VEGF ligands (A, C, and D) in CRC patients. Expression was determined by ELISA. Results: VEGF-A monitoring was performed in 148 CRC patients preoperatively and VEGF-C and -D monitoring was performed in 52 metastatic CRC patients. Patients with high VEGF-A had significantly shorter recurrence free survival (p = 0.00438). Univariate analysis associating with recurrence detected high VEGF-A, high pathological stage, and with lymph node metastasis were risk factors, and high VEGF-A was identified as an independent risk factor of recurrence by multivariate analysis. There was no significant difference in prognosis between metastatic CRC patients with high and low VEGF-D in early-line treatment, however, in late line patients with high VEGF-D had significantly worse prognosis than those with low VEGF-D (p = 0.0121). When they had treatment with bevacizumab, same result was seen in late line (p = 0.0416). VEGF-C showed no significant correlation with prognosis. Conclusions: Preoperative high VEGF-A is an important risk factor of recurrence and VEGF targeting drugs might be useful as an adjuvant chemotherapy for the patients with high VEGF-A. In late line chemotherapy, patients with high VEGF-D had poor prognosis in regardless of bevacizumab, therefore, they will be candidates of other anti-VEGF drugs than bevacizumab in late line chemotherapy. Measurement of plasma VEGF level can have benefit for the treatment of CRC patients to predict their recurrence and prognosis. It would be helpful for VEGF targeting drug selection and provide useful information for better treatment strategy.

Bevacizumab is associated with delayed anastomotic leak after low anterior resection with preoperative radiotherapy for rectal cancer: a case report

Background

Bevacizumab is an anti-angiogenesis agent used to treat patients with metastatic colorectal cancer and is associated with a variety of complications. We present a patient with rectal cancer who developed a delayed anastomotic leak more than 5 years after undergoing low anterior resection.

Case report

A 78-year-old man with hematochezia was diagnosed with two synchronous rectal cancers 7 years prior to presentation. Preoperative chemo-radiotherapy was given followed by a very low anterior resection. During follow-up, multiple lymph node metastases developed, which were treated with chemotherapy. First-line chemotherapy, capecitabine, oxizaliplatin, and bevacizumab, was given over 3 years, and second-line chemotherapy, capecitabine, irinotecan, and bevacizumab, was administered over a 3-month period. After the last treatment, the patient presented with pneumaturia and fecaluria. Computed tomography scan revealed extraluminal air between the prostate and rectum, adjacent to the anastomotic site. Ulceration and fistula formation were observed on colonoscopy, and contrast radiography demonstrated a fistula at the anastomotic site. An anastomotic-urethral fistula was diagnosed and transverse colostomy was performed.

Conclusions

This patient highlights a rare late adverse event at the anastomotic site associated with bevacizumab treatment and preoperative chemo-radiotherapy. Signs and symptoms suggesting anastomotic complications should be thoroughly evaluated during bevacizumab treatment, even long after surgical resection.

The surgical treatment of acute and severe diversion colitis mimicking ulcerative colitis: a case report

BACKGROUND

Diversion colitis (DC) is characterized by nonspecific inflammation in the remaining colon or rectum, and loss of the fecal stream plays a major role in the disease's development. Although the majority of patients are asymptomatic, medical and/or surgical treatment is required for those who are symptomatic. There is a particular interest on how to manage patients with acute and severe clinical presentations, but the pathogenesis is not fully understood. We report the rare case of a man with acute and severe DC mimicking ulcerative colitis (UC) with extra-intestinal manifestations that was successfully managed with surgical treatment.

CASE PRESENTATION

A 68-year-old man with a history of laparoscopic intersphincteric resection of the rectum with diverting loop ileostomy for lower rectal cancer suffered from anastomotic stenosis requiring repeated endoscopic dilatation. His loop stoma was not reversed because these treatments were unsuccessful. He denied having a history of inflammatory bowel disease. Twelve years postoperatively, he developed a perineal abscess requiring drainage. Subsequently, he developed a high-grade fever, bloody discharge per anus, and skin ulcers in the right ankle and around the stoma. Because culture tests were negative for bacteria, it was deemed that his acute illness reflected an inflammatory response rather than an infectious disease. Colonoscopy revealed anastomotic stenosis, a colonic fistula, and mucosa that hemorrhaged easily, with lacerations. A pathological examination with biopsy revealed inflammatory infiltration without malignancy. After reviewing the patient's clinical episodes and discussing the case with physicians in multiple specialties, we performed total colectomy with end ileostomy in accordance with the abdominoperineal resection. The postoperative course was uneventful. A resected specimen showed atrophic mucosa with the disappearance of haustra in the distal colon, as well as edematous and dilated mucosa in the proximal colon. The pathological diagnosis was suggestive of UC, including erosion and ulceration in edematous wall, crypt abscess, and inflammatory infiltration into the mucosa. The skin ulcers in the right ankle and around the stoma healed over time.

CONCLUSIONS

DC can eventuate in a long-term period after fecal diversion surgery, possibly with extra-intestinal manifestations mimicking UC. Surgical treatment seems feasible for patients with acute and severe DC.

Intussusception secondary to descending colon lipoma presenting with simultaneous acute appendicitis

We report a patient with a descending colon lipoma presenting with hematochezia who developed intussusception, which was simultaneously accompanied by acute appendicitis. A 43-year-old man presented with hematochezia. Colonoscopy revealed a submucosal tumor with a reddish surface in the descending colon. A solid mass with fat density value measuring 5 cm in diameter was observed in the descending colon on CT. While awaiting elective resection, the patient developed lower abdominal pain. CT demonstrated antegrade colo-colonic intussusception in the descending colon. Simultaneously, the appendix was inflamed with a high density intraluminal lesion suspected to be a fecalith. The diagnosis of simultaneous intussusception and acute appendicitis was made. Appendectomy and partial resection of the descending colon was performed. Histopathological examination was consistent with descending colon lipoma and acute appendicitis. The mechanism for developing hematochezia and the risk for development of colo-colonic intussusception due to large colon lipoma and acute appendicitis were highlighted.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) Guidelines 2016 for the Clinical Practice of Hereditary Colorectal Cancer (Translated Version)

Hereditary colorectal cancer accounts for less than 5% of all colorectal cancer cases. Some of the unique characteristics that are commonly encountered in cases of hereditary colorectal cancer include early age at onset, synchronous/metachronous occurrence of the cancer, and association with multiple cancers in other organs, necessitating different management from sporadic colorectal cancer. While the diagnosis of familial adenomatous polyposis might be easy because usually 100 or more adenomas that develop in the colonic mucosa are in this condition, Lynch syndrome, which is the most commonly associated disease with hereditary colorectal cancer, is often missed in daily medical practice because of its relatively poorly defined clinical characteristics. In addition, the disease concept and diagnostic criteria for Lynch syndrome, which was once called hereditary non-polyposis colorectal cancer, have changed over time with continual research, thereby possibly creating confusion in clinical practice. Under these circumstances, the JSCCR Guideline Committee has developed the "JSCCR Guidelines 2016 for the Clinical Practice of Hereditary Colorectal Cancer (HCRC)," to allow delivery of appropriate medical care in daily practice to patients with familial adenomatous polyposis, Lynch syndrome, or other related diseases. The JSCCR Guidelines 2016 for HCRC were prepared by consensus reached among members of the JSCCR Guideline Committee, based on a careful review of the evidence retrieved from literature searches, and considering the medical health insurance system and actual clinical practice settings in Japan. Herein, we present the English version of the JSCCR Guidelines 2016 for HCRC.

Monitoring circulating tumor DNA revealed dynamic changes in KRAS status in patients with metastatic colorectal cancer

KRAS mutated circulating tumor DNA (MctDNA) can be monitored in the blood of patients with metastatic colorectal cancer (mCRC), but dynamic changes have not been determined. Four hundred and fifty-seven plasma samples were collected prospectively from 85 mCRC patients who underwent chemotherapy. MctDNA in plasma was detected by droplet digital PCR, and the percentage of MctDNA in total circulating cell-free DNA was calculated. KRAS assessment in tumor tissues showed 29 patients with the mutant-type (MT) and 56 patients with the wild-type (WT). Twenty-three of 29 MT patients (79.3%) and 28 of 56 WT patients (50.0%) showed MctDNA. Emergence of MctDNA was recognized during treatments with various drugs. Regardless of KRAS status in tumor tissues, patients with MctDNA in blood showed poor progression-free survival with first-line treatment. Median percentage of MctDNA accounted for 10.10% in MT patients and 0.22% in WT patients. These differences between MT and WT likely affected patterns of changes in MctDNA. KRAS monitoring identified dynamic changes in MctDNA, such as continuous, intermittent, and transient changes (quick elevation and disappearance). Emergence of MctDNA involved drug resistance, except for transient changes, which were seen in WT patients and likely corresponded with the drug response. Transient changes could be involved in recovery of sensitivity to anti-EGFR antibody in WT patients. Monitoring MctDNA during various treatments showed dynamic changes in KRAS status and could provide useful information for determining treatments for patients with mCRC.

Successful treatment of recurrent stoma prolapse after Hartmann's procedure through ileorectal anastomosis: A case report

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The patient with Parkinson’s disease had stoma prolapse after Hartmann’s procedure.

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Local procedure had failed, and stoma reversal was considered to be favorable.

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We assumed that stoma reversal alone led to worsening of concomitant constipation.

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We performed resection of the remnant colon with ileorectal anastomosis.

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It may be an optimal treatment for patients with concomitant colonic motility disorder.

Introduction

Treatment strategy for recurrent stoma prolapse has not been well-established because of the rarity and complexity of the condition. We report a case of recurrent stoma prolapse that was successfully managed using unique surgical treatments.

Presentation of case

A 72-year-old man with a history of Parkinson's disease presented with transverse (T3N0M0) and sigmoid (T3N0M0) colon cancer. Considering the status of large bowel obstruction, Hartmann's procedure was indicated. Four months after surgery, stoma prolapse occurred, which became irreducible. Six months after surgery, local resection of the prolapsed bowel was performed. The patient continued to receive laxatives for bowel movement control and his abdomen remained distended. Ten months later, stoma prolapse recurred with evident bowel dilatation. Initially, we planned Hartmann’s reversal. However, as the patient had intractable constipation secondary to Parkinson’s disease, resection of the proximal colon and ileorectal anastomosis were considered as the treatment choices. Therefore, we performed right colectomy with ileorectal anastomosis. At 1.5 years after the last surgery, complications such as small bowel obstruction, difficulty in defecation, or fecal incontinence were not detected.

Discussion

The cause of stoma prolapse is generally ascribed to various anatomical factors such as redundant intestine, high intra-abdominal pressure, and intraperitoneal route. Stoma prolapse is also influenced by other factors, including old age, obesity, and the severity of illness that necessitated stoma creation. In this case, the decision regarding surgical management was complicated by colonic motility disorder with concomitant Parkinson’s disease.

Conclusion

We suggest that ileorectal anastomosis may be an optimal surgical treatment for patients with recurrent stoma prolapse and concomitant colonic motility disorder who have undergone Hartmann’s procedure.

Overexpression of satellite alpha transcripts leads to chromosomal instability via segregation errors at specific chromosomes

The impairment of the stability of the chromosomal structure facilitates the abnormal segregation of chromosomes, thus increasing the risk of carcinogenesis. Chromosomal stability during segregation is managed by appropriate methylation at the centromere of chromosomes. Insufficient methylation, or hypomethylation, results in chromosomal instability. The centromere consists of satellite alpha repetitive sequences, which are ideal targets for DNA hypomethylation, resulting in the overexpression of satellite alpha transcript (SAT). The overexpression of SAT has been reported to induce the abnormal segregation of chromosomes. In this study, we verified the oncogenic pathway via chromosomal instability involving DNA hypomethylation and the overexpression of SAT. For this purpose, we constructed lentiviral vectors expressing SAT and control viruses and then infected human mammary epithelial cells with these vectors. The copy number alterations and segregation errors of chromosomes were evaluated by microarray-based comparative genomic hybridization (array CGH) and immunocytochemistry, respectively. The levels of hypomethylation of satellite alpha sequences were determined by MethyLight polymerase chain reaction. Clinical specimens from 45 patients with breast cancer were recruited to verify the data in vitro. The results of immunocytochemistry revealed that the incidence of segregation errors was significantly higher in the cells overexpressing SAT than in the controls. An array CGH identified the specific chromosomes of 8q and 20q as frequent sites of copy number alterations in cells with SAT overexpression, although no such sites were noted in the controls, which was consistent with the data from clinical specimens. A regression analysis revealed that the expression of SAT was significantly associated with the levels of hypomethylation of satellite alpha sequences. On the whole, the overexpression of SAT led to chromosomal instability via segregation errors at specific chromosomes in connection with DNA hypomethylation, which was also recognized in clinical specimens of patients with breast cancer. Thus, this oncogenic pathway may be involved in the development of breast cancer.

Dynamics and characteristics of KRAS mutated circulating tumor DNA in patients with metastatic colorectal cancer during various treatments

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Background: KRAS mutated circulating tumor DNA (MctDNA) can be detected in blood of patients with metastatic colorectal cancer (mCRC) but its dynamics and characteristics during anti-EGFR and other treatments are not well known. Methods: Four hundred and fifty-one plasma samples were collected prospectively from 85 patients who underwent chemotherapy due to mCRC in 2014 - 2017. KRAS mutation in codon12/13/61 was explored in tumor tissues and plasma. Results: KRAS assessment in tumor tissues showed 29 patients with KRAS mutation (MT), 56 patients without mutation (WT). Sensitivity and specificity of MctDNA was 86.4% and 100%, respectively. In 29 patients with MT, significant difference in PFS was observed between patients with MctDNA and without during 1st line treatment (3.0 months vs.15.0 months; p = 0.005). In 56 patients with WT, 27 patients showed MctDNA during various treatments. Different characteristics in appearance were recognized during several treatments including anti-VEGF, TAS-102 and regorafenib. KRAS mutation in codon12/13 was appeared before and after disease progression. KRAS mutation in codon 61 was, however, frequently detected before disease progression. A spike like appearance of KRAS mutation in codon12/13 was likely seen in response to induction of the sequential treatment. Significant difference in PFS was observed between patients with MctDNA and without during 1st line treatment (6.0 months vs. 13.0 months; p = 0.0017), as was observed in patients with MT. Conclusions: Dynamics and characteristics of KRAS status in blood may be involved in the treatment response and outcome in mCRC patients.

En bloc pancreaticoduodenectomy and right hemicolectomy for locally advanced right-sided colon cancer

AIM

To assess the usefulness of en bloc right hemicolectomy with pancreaticoduodenectomy (RHCPD) for locally advanced right-sided colon cancer (LARCC).

METHODS

We retrospectively reviewed the database of Saitama Medical Center, Jichi Medical University, between January 2009 and December 2016. During this time, 299 patients underwent radical right hemicolectomy for right-sided colon cancer. Among them, 5 underwent RHCPD for LARCC with tumor infiltration to adjacent organs. Preoperative computed tomography (CT) was routinely performed to evaluate local tumor infiltration into adjacent organs. During the operation, we evaluated the resectability and the amount of infiltration into the adjacent organs without dissecting the adherent organs from the cancer. When we confirmed that radical resection was feasible and could lead to R0 resection, we performed RHCPD. The clinical data were carefully reviewed, and the demographic variables, intraoperative data, and postoperative parameters were recorded.

RESULTS

The median age of the 5 patients who underwent RHCPD for LARCC was 70 years. The tumors were located in the ascending colon (three patients) and transverse colon (two patients). Preoperative CT revealed infiltration of the tumor into the duodenum in all patients, the pancreas in four patients, the superior mesenteric vein (SMV) in two patients, and tumor thrombosis in the SMV in one patient. We performed RHCPD plus SMV resection in three patients. Major postoperative complications occurred in 3 patients (60%) as pancreatic fistula (grade B and grade C, according to International Study Group on Pancreatic Fistula Definition) and delayed gastric empty. None of the patients died during their hospital stay. A histological examination confirmed malignant infiltration into the duodenum and/or pancreas in 4 patients (80%), and no patients showed any malignant infiltration into the SMV. Two patients were histologically confirmed to have tumor thrombosis in the SMV. All of the tumors had clear resection margins (R0). The median follow-up time was 77 mo. During this period, two patients with tumor thrombosis died from liver metastasis. The overall survival rates were 80% at 1 year and 60% at 5 years. All patients with node-negative status (n = 2) survived for more than seven years.

CONCLUSION

This study showed that the long-term survival is possible for patients with LARCC if RHCPD is performed successfully, particularly in those with node-negative status.

Local control of sphincter-preserving procedures and abdominoperineal resection for locally advanced low rectal cancer: Propensity score matched analysis

Sphincter‐preserving procedures (SPPs) for surgical treatment of low‐lying rectal tumors have advanced considerably. However, their oncological safety for locally advanced low rectal cancer compared with abdominoperineal resection (APR) is contentious. We retrospectively analyzed cohort data of 1500 consecutive patients who underwent elective resection for stage II‐III rectal cancer between 2010 and 2011. Patients with tumors 2‐5 cm from the anal verge and clinical stage T3‐4 were eligible. Primary outcome was 3‐year local recurrence rate, and confounding effects were minimized by propensity score matching. The study involved 794 patients (456 SPPs and 338 APR). Before matching, candidates for APR were more likely to have lower and advanced lesions, whereas SPPs were carried out more often following preoperative treatment, by laparoscopic approach, and at institutions with higher case volume. After matching, 398 patients (199 each for SPPs and APR) were included in the analysis sample. Postoperative morbidity was similar between the SPPs and APR groups (38% vs 39%; RR 0.98, 95% CI 0.77‐1.27). Margin involvement was present in eight patients in the SPPs group (one and seven at the distal and radial margins, respectively) and in 12 patients in the APR group. No difference in 3‐year local recurrence rate was noted between the two groups (11% vs 14%; HR 0.77, 95% CI 0.42‐1.41). In this observational study, comparability was ensured by adjusting for possible confounding factors. Our results suggest that SPPs and APR for locally advanced low rectal cancer have demonstrably equivalent oncological local control.

Morphological response contributes to patient selection for rescue liver resection in chemotherapy patients with initially un-resectable colorectal liver metastasis

Morphological response is considered an improved surrogate to the Response Evaluation Criteria in Solid Tumors (RECIST) model with regard to predicting the prognosis for patients with colorectal liver metastases. However, its use as a decision-making tool for surgical intervention has not been examined. The present study assessed the morphological response in 50 patients who underwent chemotherapy with or without bevacizumab for initially un-resectable colorectal liver metastases. Changes in tumor morphology between heterogeneous with uncertain borders and homogeneous with clear borders were defined as an optimal response (OR). Patients were also assessed as having an incomplete response (IR), and an absence of marked changes was assessed as no response (NR). No significant difference was observed in progression-free survival (PFS) between complete response/partial response (CR/PR) and stable disease/progressive disease (SD/PD), according to RECIST. By contrast, PFS for OR/IR patients was significantly improved compared with that for NR patients (13.2 vs. 8.7 months; P=0.0426). Exclusion of PD enhanced the difference in PFS between OR/IR and NR patients (15.1 vs. 9.3 months; P<0.0001), whereas no difference was observed between CR/PR and SD. The rate of OR and IR in patients treated with bevacizumab was 47.4% (9/19), but only 19.4% (6/31) for patients that were not administered bevacizumab. Comparison of the survival curves between OR/IR and NR patients revealed similar survival rates at 6 months after chemotherapy, but the groups exhibited different survival rates subsequent to this period of time. Patients showing OR/IR within 6 months appeared to be oncologically stable and could be considered as candidates for surgical intervention, including rescue liver resection. Comparing the pathological and morphological features of the tumor with representative optimal response, living tumor cells were revealed to be distributed within the area of vascular reconstruction induced by bevacizumab, resulting in a predictive value for prognosis in the patients treated with bevacizumab. The present findings provided the evidence for physicians to consider patients with previously un-resectable metastatic colorectal cancer as candidates for surgical treatment. Morphological response is a useful decision-making tool for evaluating these patients for rescue liver resection following chemotherapy.

Laparoscopic resection of retroperitoneal ectopic thyroid tissue

A 43-year-old otherwise healthy woman was found to have a retroperitoneal mass during a routine medical examination and was referred for further evaluation. Abdominal CT scan showed a well-delineated, low-density area that exhibited heterogeneous contrast enhancement. The area measured about 20 mm in size and was to the left of the aorta at the level of the inferior mesenteric artery. MRI showed a mass with heterogeneous hypointensity on T₁ -weighted images and heterogeneous hyperintensity on T₂ -weighted images. PET-CT scan showed slightly increased ¹⁸ F-fluorodeoxyglucose accumulation within the mass. Laparoscopic resection was performed. A smooth, brownish mass was seen in the retroperitoneum and was resected with minimal blood loss. Histopathological examination showed a nodular mass measuring 40 × 26 × 20 mm that was composed solely of ectopic thyroid tissue. This case shows the exceptional development of ectopic thyroid in the infradiaphragmatic retroperitoneum and demonstrates the usefulness of laparoscopy for resecting such masses.

Difference in appearance of KRAS mutated circulating tumor DNA in patients with metastatic colorectal cancer during treatments

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Background: Emergence of KRAS mutation in blood is observed in colorectal cancer patients who undergo chemotherapy, but its clinical significance is not well known. In this study, we focused on the difference in appearance of KRAS mutated circulating tumor DNA (MctDNA) and elucidated its association with treatments. Methods: Four hundred and fifty-one plasma samples were collected prospectively from 85 patients (pts) who underwent chemotherapy due to metastatic colorectal cancer in 2014 - 2016. Seven types of KRAS mutation in MctDNA were detected by droplet digital PCR creating oil droplets. To exclude false positive detection, mutation was validated. MctDNA amplified in oil droplets was selectively sorted by On-chip sorting system and mutation was determined by Sanger sequencing. Results: KRAS assessment in tumor tissues showed 29 pts with KRAS mutation (MT), 56 pts without KRAS mutation (WT). Among 29 pts with MT, KRAS assessment in plasma displayed 23 pts with MctDNA and 6 pts without MctDNA. The type of mutation in MctDNA was consistent with that detected in tumor tissues, indicating mutual exclusivity in KRAS mutation was confirmed. In 56 pts with WT, 28 pts showed MctDNA during treatments. Difference in appearance of MctDNA was recognized in several treatments. Gradual increase in detection of MctDNA was observed with anti-EGFR antibody, resulted in treatment resistance. Transient spike elevation was frequently seen in TAS-102, which associated with drug response. No specific appearance was recognized during treatments with other drugs including anti-VEGF antibody. MctDNA in oil droplets were successfully sorted even if a few droplets were targeted, and mutation was confirmed. Conclusions: Difference in appearance of MctDNA may associate with treatment response in patients with metastatic colorectal cancer during treatments. [Table: see text]

Sequential administration of XELOX and XELIRI is effective, feasible and well tolerated by patients with metastatic colorectal cancer

Sequential administration of the chemotherapy regimes capecitabine and oxaliplatin (XELOX) and capecitabine and irinotecan (XELIRI) in the first- to second-line treatment setting would allow patients to be managed more easily in an outpatient unit. However, a small number of studies have raised concerns of cumulative adverse events as a consequence of the continuous use of capecitabine. To investigate this, the present study conducted a retrospective review of 81 consecutive metastatic colorectal cancer (mCRC) patients treated with the oxaliplatin, fluorouracil and leucovorin-irinotecan, fluorouracil and leucovorin (FOLFOX-FOFIRI/F-F) regimen (n=40) or the XELOX-XELIRI (X-X) regimen (n=41) in first- to second-line chemotherapy in Saitama Medical Center between 2006 and 2012. The disease control rate (DCR), the progression free survival (PFS), the overall survival (OS) and the time to failure of strategy (TFS) from first to second-line chemotherapy, as well as adverse events, were assessed and compared between patients receiving X-X or F-F. A total of 10 and 20 patients were additionally treated with bevacizumab in the F-F and X-X regimens, respectively, during first or second-line chemotherapy. There was no significant difference in DCR and the median PFS between the two regimens for first or second-line chemotherapy. There was no significant difference in the median OS and TFS between the two regimens (OS=24.5 and TFS=14 months in the F-F vs. 23.2 and 12.0 months in the X-X). Regarding adverse events, 45.0% of patients (18/40) exhibited grade 3-4 neutropenia throughout treatment with F-F. Whilst, 15.0% of patients (6/41) exhibited grade 3 hypertension throughout treatment with X-X, which was effectively controlled by a single antihypertensive drug. The results show that sequential administration of X-X is as effective and feasible as F-F treatment, while additionally reducing the frequency of infusion visits and eliminating the need for a central venous access device or home infusion pump, thereby offering a more convenient treatment option to patients with mCRC.

Clinical and molecular assessment of regorafenib monotherapy

Regorafenib has shown survival benefits in metastatic colorectal cancer patients who were exacerbated after all standard therapies. Some patients, however, exhibit severe adverse events (AEs) resulting in treatment discontinuation. Therefore, the selection of patients likely to benefit from regorafenib is crucial. Twenty patients were treated with regorafenib for metastatic colorectal cancer; 122 plasma samples were taken from 16 of these patients for monitoring of circulating tumor DNA (ctDNA) in the blood. The treatment response, AEs, overall survival (OS), progression-free survival (PFS) and tumor morphologic changes on CT images were evaluated. KRAS mutant ctDNA was determined using digital PCR. Median PFS and OS were 2.5 and 5.9 months, respectively. Treatment was discontinued because of disease progression (PD) in 10 patients, and AEs in another 10 patients. AEs included hyperbilirubinemia, severe fatigue and skin rash. Hyperbilirubinemia was seen in two patients with multiple bilateral liver metastases, and severe fatigue in another 2 patients with poor performance status (PS). These severe AEs resulted in treatment discontinuation. Ten patients had a median PFS of 2.1 months with AE related discontinuation; PD occurred at 3.5 months (p=0.00334). Four patients exhibited a morphologic response, achieving better PFS times of 3.5, 5.3, 5.6 and 14.2 months. Emergence of the KRAS mutation in ctDNA was observed during anti-EGFR antibody treatment in 3 patients among 11 with KRAS wild-type tumors; it was detectable in the blood prior to radiographic detection of PD. Moreover, the KRAS mutation declined in two patients during regorafenib monotherapy. These patients were re-challenged with anti-EGFR antibody. Patients with extensive multiple liver metastases or poor PS are unlikely to benefit from regorafenib. Patients with a morphologic response will probably benefit from regorafenib with adequate management of other AEs. KRAS monitoring in ctDNA could be useful regarding treatment response and in determining treatment strategy.

Combined assessment using optical colonoscopy and computed tomographic colonography improves the determination of tumor location and invasion depth

INTRODUCTION

An accurate assessment of the depth of tumor invasion in patients with colon cancer is an important part of the preoperative evaluation. Whether computed tomographic colonography (CTC) or optical colonoscopy (OC) is better to accurately determine tumor location and invasion depth has not been definitively determined. The aim of this study was to determine the diagnostic accuracy of tumor localization and tumor invasion depth of colon cancer by preoperative OC alone or combined with CTC.

METHODS

Study participants include 143 patients who underwent both preoperative CTC using automated CO₂ insufflation and OC from July 2012 to August 2013.

RESULTS

The accuracy of tumor localization was significantly better with CTC than with OC (OC, 90%; CTC, 98%; P < 0.05). No tumor in the descending colon was localized accurately via OC alone. The accuracy of tumor invasion depth was better with CTC plus OC than with OC alone (OC, 55%; CTC, 73%; P < 0.05).

CONCLUSIONS

OC combined with CTC provides a more accurate preoperative determination of tumor localization and invasion depth than OC alone.

Clinical characteristics of synchronous colorectal cancers in Japan

BACKGROUND

Incidence and clinical characteristics of synchronous colorectal cancer (sCRC) patients significantly vary among studies, likely due to differences in surveillance methodology. If remain undetected, sCRC can progress to more advanced stages seriously aggravating patient prognosis. We studied the incidence and clinicopathological characteristics of Japanese patients with sCRCs who underwent surgery for primary CRC and received exhaustive perioperative surveillance.

METHODS

We recruited 1005 patients with surgically resected CRCs between January 2007 and December 2011. The associations of clinical and pathological factors with sCRC development were assessed by univariate and multivariate logistic regression.

RESULTS

Eighty-four patients (8.4 %) developed sCRCs, 16 of them (19.0 %) harboring three or more cancers. Companion sCRCs were smaller and earlier stage than the index lesion (P < 0.0001). In multivariate analysis, advanced age (odds ratio (OR) 1.03 per year; P = 0.009) and left colon tumor location (OR 1.78; P = 0.013) are associated with higher risk of sCRCs, particularly in females. Overall survival did not differ between solitary CRC and sCRC (P = 0.62).

CONCLUSIONS

Our results highlight the importance of perioperative colonoscopy examination to ensure the absence of sCRCs that, being small and early staged, are more difficult to detect. The incidence of sCRC, and notably of triple or more sCRCs, was higher than previously recognized. Because they are also significantly higher than expected by merely stochastic accumulation of individual cancerous lesions, we suggest that the occurrence of many sCRC reflects a hitherto uncharacterized predisposition condition.