Guideline for gynecological practice in Japan: Japan Society of Obstetrics and Gynecology and Japan Association of Obstetricians and Gynecologists 2023 edition.

Twelve years after the first edition of The Guideline for Gynecological Practice, which was jointly edited by The Japan Society of Obstetrics and Gynecology and The Japan Association of Obstetricians and Gynecologists, the 5th Revised Edition was published in 2023. The 2023 Guidelines includes 5 additional clinical questions (CQs), which brings the total to 103 CQ (12 on infectious disease, 30 on oncology and benign tumors, 29 on endocrinology and infertility and 32 on healthcare for women). Currently, a consensus has been reached on the Guidelines, and therefore, the objective of this report is to present the general policies regarding diagnostic and treatment methods used in standard gynecological outpatient care that are considered appropriate. At the end of each answer, the corresponding Recommendation Level (A, B, C) is indicated.

Adverse effect of donor-specific anti-human leukocyte antigen (HLA) antibodies directed at HLA-DP/-DQ on engraftment in cord blood transplantation.

BACKGROUND AIMS: While donor-specific anti-human leukocyte antigen (HLA) antibodies (DSAs) in the recipient before transplantation are associated with graft failure in cord-blood transplantation (CBT), effects of DSAs other than against HLA-A, -B or -DRB1 on transplantation outcomes remained poorly understood. METHODS: We retrospectively analyzed 567 single-unit CBT recipients to evaluate impact of DSAs against HLA-DP and -DQ on CBT outcomes. RESULTS: Among 143 recipients (25.2%) who had anti-HLA antibodies, nine harbored DSAs against HLA-DP or -DQ. DSAs against HLA-DP or -DQ were associated with a significantly lower neutrophil engraftment rate (55.6% versus 91.8%, P = 0.032) and with a marginally lower platelet engraftment rate (46.7% versus 75.3%, P = 0.128) at day 100 after transplantation, compared with patients without anti-HLA antibodies. Time to neutrophil and platelet engraftment in patients with DSAs for HLA-DP or -DQ was significantly longer than that in patients without anti-HLA antibodies (median, 25 versus 21 days, P = 0.002 in neutrophil; median 61 versus 46 days, P = 0.014 in platelet). Cumulative incidence of bacterial infection at day 100 was significantly greater (88.9% versus 57.1%, P = 0.024), and re-transplant-free survival was marginally lower (55.6% versus 76.8%, P = 0.132) in patients with DSAs against HLA-DP or -DQ, compared with those without anti-HLA antibodies. These findings suggest that DSAs against HLA-DP or -DQ lead to unfavorable engraftment, which may increase risk of bacterial infection, and reduce survival soon after CBT. CONCLUSIONS: Our results suggest the importance of evaluating DSAs against HLA-DP and -DQ in recipients before selecting CB units.

Heterologous expression of the lectin CmRlec from Cordyceps militaris (Cordycipitaceae, Ascomycota) in Escherichia coli.

Ascomycete lectins may play an important role in their life cycle. In this report, we mined a ricin B-type lectin, named CmRlec, from the Cordyceps militaris genome by homology search. Furthermore, we succeeded in the soluble expression of CmRlec using ß-glucuronidase as a solubilization tag and demonstrated that this lectin is a novel chitin-recognizing lectin.

Quantification of residual cryoprotectants and cytotoxicity in thawed bovine ovarian tissues after slow freezing or vitrification.

STUDY QUESTION: How much residual cryoprotectant remains in thawed/warmed ovarian tissues after slow freezing or vitrification? SUMMARY ANSWER: After thawing/warming, at least 60 min of diffusion washing in media was necessary to significantly reduce the residual cryoprotectants in ovarian tissues frozen by slow freezing or vitrification. WHAT IS KNOWN ALREADY: Ovarian tissue cryopreservation (OTC) by slow freezing has been the conventional method; while the vitrification method has gained popularity for its practicality. The main concern about vitrification is how much potentially toxic residual cryoprotectant remains in the warmed tissues at the time of transplantation. STUDY DESIGN, SIZE, DURATION: This was an animal study using the ovarian tissues from 20 bovine ovaries. The duration of this study was from 2018 to 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: Ovarian cortex tissues were prepared from 20 bovine ovaries and assigned randomly to groups of fresh (non-frozen) control, slow freezing with 1.5 M dimethyl sulfoxide (DMSO), 1.5 M 1,2-propanediol (PROH) and vitrification with 35% ethylene glycol (EG). The residual cryoprotectant concentrations in thawed/warmed tissues were measured by gas chromatography at the following time points: frozen (before thawing/warming), 0 min (immediately after thawing/warming), 30, 60 and 120 min after diffusion washing in media. Next, the ultrastructural changes of primordial follicles, granulosa cells, organelles and stromal cells in the ovarian tissues (1 mm × 1 mm × 1 mm) were examined in fresh (non-frozen) control, slow freezing with DMSO or PROH and vitrification with EG groups. Real-time quantitative PCR was carried out to examine the expressions of poly (ADP-ribose) polymerase-1 (PARP1), a DNA damage sensor and caspase-3 (CASP3), an apoptosis precursor, in thawed/warmed ovarian tissues that were washed for either 0 or 120 min and subsequently in tissues that were ex vivo cultured for 24 or 48 h. The same set of tissues were also used to analyze the protein expressions of gamma H2A histone family member X (γH2AX) for DNA double-strand breaks and activated caspase-3 (AC3) for apoptosis by immunohistochemistry. MAIN RESULTS AND THE ROLE OF CHANCE: The residual cryoprotectant concentrations decreased with the extension of diffusion washing time. After 60 min washing, the differences of residual cryoprotectant between DMSO, PROH and EG were negligible (P > 0.05). This washing did not affect the tissue integrity or significantly elevate the percentage of AC3 and γH2AX positive cells, indicating that tissues are safe and of good quality for transplantation. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Since the study was performed with ovarian tissues from bovines, generalizability to humans may be limited. Potential changes in ovarian tissue beyond 120 min were not investigated. WIDER IMPLICATIONS OF THE FINDINGS: This study addresses concerns about the cytotoxicity of EG in warmed ovarian tissues and could provide insights when devising a standard vitrification protocol for OTC. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by a Grant-in-Aid for Scientific Research (B) from the Japan Society for the Promotion of Science to N.S.

Value of adjuvant chemotherapy and informed microscopic examination for occult gynecologic cancer detected upon risk-reducing salpingo-oophorectomy after chemotherapy for BRCA1/2-associated breast cancer: a case report.

BRCA1/2 mutation carriers are at high risk for type II ovarian, fallopian tube or peritoneal cancer. Although risk-reducing salpingo-oophorectomy plays an important role in the prevention of these BRCA1/2-associated gynecological cancers, occult ovarian, fallopian tube, or peritoneal cancer is discovered upon risk-reducing salpingo-oophorectomy in 1-4% of BRCA1/2 mutation carriers. Notably, around 30% of BRCA1/2 mutation carriers who undergo risk-reducing salpingo-oophorectomy have undergone adjuvant chemotherapy for breast cancer. We describe the discovery and treatment of occult cancer at the edge of the left fimbria in a BRCA1 mutation carrier who had, just a short time previously, undergone neoadjuvant paclitaxel plus carboplatin (TC) chemotherapy for triple-negative breast cancer. During subsequent risk-reducing salpingo-oophorectomy, a 5.5-mm nodule was observed at the edge of the left fimbria. Microscopic examination of the tumour tissue revealed high-grade serous carcinoma with degenerate tumour cells and fibrosis. Peritoneal fluid was negative for cancer cells. Two months later, hysterectomy, omentectomy and retroperitoneal lymphadenectomy were performed. The final diagnosis was stage FIGO IA fallopian tube cancer. Adjuvant chemotherapy (TC administered every 3 weeks) was applied, and there has been no evidence of recurrence for 5 years. In applying gynecologic surgery and adjuvant chemotherapy, we followed the general recommendation for stage IA fallopian tube cancer. There is no standard strategy for the treatment of occult fallopian tube cancer detected after chemotherapy for BRCA1-associated triple-negative breast cancer. According to our experience in this case, we believe the clinical value of staging laparotomy in cases of a small occult BRCA1/2-associated gynecological cancer should be further investigated.

An efficient heterologous Escherichia coli-based expression system for lectin production from Pleurocybella porrigens.

In this study, we report a more efficient heterologous expression of lectin from Pleurocybella porrigens (PPL) using an Escherichia coli-based expression system. The yield (9.3 mg/L culture broth) of recombinant PPL (rPPL) using this expression system was increased approximately 9-fold compared to our previous study. The rPPL obtained in this study exhibited the same biochemical properties as the native PPL.

Assessing tumor response to neoadjuvant chemoradiation in rectal cancer with rectoscopy and 18F-FDG PET/CT: results from a prospective series.

INTRODUCTION: rectoscopy and 18F-FDG PET/CT as a diagnostic algorithm for the assessment of tumor response in rectal cancer after neoadjuvant chemoradiation therapy (CRT) is very useful. MATERIAL AND METHODS: this was a prospective longitudinal study in patients with locally advanced rectal cancer treated with neoadjuvant CRT. Patients were assessed after CRT completion with a digital rectal examination, proctoscopy and 18F-FDG PET/CT. Patients were subdivided as clinical (cCR) or radiologic (rCR) responders and non-responders according to tumor response. Clinical and radiological re-assessment was compared with the surgical specimen. Pathological tumor regression (pCR) grade was determined according to Mandard's classification. Of the 68 patients included, 15 (22 %) presented pCR in the surgical specimen and tumor persistence (non-PCR) was detected in the remaining 53 (78 %). Clinical assessment (DRE+ rectoscopy) identified 15 patients as cCR and 53 as non-cCR, two were false positives and two were false negatives. The overall accuracy was 94 %. 18F-FDG PET/CT identified 18 patients as rCR and 50 as non-rCR, one was a false positive and four were false negatives. The overall accuracy was 92 %. A combination of clinical findings and 18F-FDG PET/CT resulted in an accuracy of 96 %. The combination of clinical findings + 18F-FDG PET/CT was able to correctly identify all cases of pCR, with the exception of one case that presented a tumor regression of 80 %. In this series, 18F-PET-CT and clinical assessment had excellent accuracies in differentiating PCR from non-PCR after CRT completion. PET-CT combined with clinical assessment had a better accuracy than both modalities independently. 18F-FDG PET/CT is a valid tool that complements the clinical assessment of tumor response.

Variation in Colonoscopy Performance Measures According to Procedure Indication.

BACKGROUND & AIMS: Most fulfillment and benchmarking information for colonoscopy quality indicators has been obtained from studies of primary screening colonoscopies. We analyzed differences in the fulfillment of colonoscopy quality indicators based on the indication for endoscopy. METHODS: We performed an observational, multicenter, cross-sectional study of 14,867 patients who underwent endoscopy procedures for gastrointestinal symptoms (40.3%), a positive result from a fecal immunochemical test (36.0%), postpolypectomy surveillance (15.3%), or primary screening (8.4%), from February 2016 through December 2017 at 14 centers in Spain. We evaluated rates of adequate colon cleansing, cecal intubation, adenoma detection, and colorectal cancer detection, among others. We used findings from primary screening colonoscopies as the reference standard. RESULTS: Fewer than 90% of patients had adequate bowel preparation; 83.1% of patients with gastrointestinal symptoms had adequate bowel preparation (odds ratio [OR] compared with patients with primary screening colonoscopies, 0.62; 95% CI, 0.49-0.78) and 85.3% of patients receiving postpolypectomy surveillance had adequate bowel preparation (OR, 0.71; 95% CI, 0.55-0.91). The cecal intubation rate was also lower in patients with gastrointestinal symptoms (93.1%) (OR, 0.34; 95% CI, 0.22-0.52). The adenoma detection rate was higher in patients with a positive result from a fecal immunochemical test (46.4%) (OR, 2.01; 95% CI, 1.71-2.35) and in patients undergoing postpolypectomy surveillance (48.2%) (OR, 1.41; 95% CI, 1.20-1.67). The highest proportion of patients with colorectal cancer was in the gastrointestinal symptom group (5.1%) (OR, 5.24; 95% CI, 2.30-11.93) and the lowest was in patients undergoing surveillance (0.8%) (OR, 0.83; 95% CI, 0.32-2.14). CONCLUSIONS: Fulfillment of colonoscopy performance measures varies substantially by indication. Policies addressing performance measures beyond colonoscopy screening procedures should be developed. Benchmarking recommendations could be adjusted according to colonoscopy indication.

Performance measures for endoscopy services: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative.

The European Society of Gastrointestinal Endoscopy (ESGE) and United European Gastroenterology present a list of key performance measures for endoscopy services. We recommend that these performance measures be adopted by all endoscopy services across Europe. The measures include those related to the leadership, organization, and delivery of the service, as well as those associated with the patient journey. Each measure includes a recommendation for a minimum and target standard for endoscopy services to achieve. We recommend that all stakeholders in endoscopy take note of these ESGE endoscopy services performance measures to accelerate their adoption and implementation. Stakeholders include patients and their advocacy groups; service leaders; staff, including endoscopists; professional societies; payers; and regulators.

The Clinical Features of Recurrent Endometrial Cancer in Japan: Chemotherapy Instead of Radiotherapy as Postoperative Adjuvant Treatment.

OBJECTIVE: Chemotherapy is a standard adjuvant treatment after primary surgery for endometrial cancer in Japan. We aimed to characterize the clinical features of recurrent endometrial cancer (REC) patients in Japan. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 112 REC patients who were primarily treated at 1 of 3 university hospitals in Japan from 2005 to 2012. We analyzed overall survival since the first recurrence (R-OS) in accordance with several factors. RESULTS: Median patient age was 64 years. The median follow-up period was 48 months. The distributions of cancer stage and histological subtype lacked distinctive features, and most patients had a high risk for recurrence at the time of the primary surgery. Although approximately 78% of patients received adjuvant chemotherapy, 85/112 patients (76%) experienced recurrence within 2 years after the initial treatment ended. For patients receiving adjuvant chemotherapy, regional lymph node (LN) and distant-site recurrence were more frequent (>40%) than vaginal or intra-abdominal recurrence. Median survival and 5-year R-OS were 27 months and 26.1%, respectively. The R-OS was significantly better for patients aged 65 years or older, those with negative peritoneal cytology at the time of primary surgery, those with recurrence within regional LN (eg, pelvic LN or para-aortic LN under the renal vein) and/or vagina, and those who underwent surgery and/or radiotherapy after recurrence. A multivariate analysis indicated that positive peritoneal cytology, a disease-free interval of less than 12 months, recurrent lesions in 2 or 3 areas, and treatment excluding surgery or radiotherapy were independent predictors of poor prognosis after recurrence. CONCLUSIONS: Adjuvant chemotherapy was insufficient to reduce the incidence of distant recurrence. The prognosis of patients recurred within regional LN and/or vagina was significantly better than that of patients with recurrence in other lesions because of treatment with surgery and/or radiotherapy. The disease-free interval was a significant prognostic factor for REC patients.

Clinical guidelines for endoscopic mucosal resection of non-pedunculated colorectal lesions.

This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Pedunculated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions.

Clinical guidelines for endoscopic mucosal resection of non-pedunculated colorectal lesions. / Guía clínica para la resección mucosa endoscópica de lesiones colorrectales no pediculadas.

This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Pedunculated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions.

Contributions of the Japanese Gynecologic Oncology Group (JGOG) in Improving the Quality of Life in Women With Gynecological Malignancies.

The Japanese Gynecologic Oncology Group (JGOG) is leading Japan in the treatment of gynecological malignancies. The JGOG consists of three treatment committees focusing on uterine cervical cancer, endometrial cancer, and ovarian cancer. Each committee makes efforts to improve treatment and diagnosis. In addition, the Supportive and Palliative Care Committee was established in 2015. Novel studies of supportive care and palliative care have been initiated by this committee. Furthermore, surveys about not only treatment results such as overall survival rates but also quality of life (QOL) and cost-effectiveness assessments are performed by the ovarian cancer committee. Improvements of patients' QOL in the treatment of gynecological malignancies were divided into three concepts as follows: QOL associated with cancer treatment, health care after cancer therapy, and progression of cancer. In this review, we report the contributions and future plans for the improvement of QOL in patients with gynecological malignancies.

Glycan profiling using formalin-fixed, paraffin-embedded tissues: Hippeastrum hybrid lectin is a sensitive biomarker for squamous cell carcinoma of the uterine cervix.

AIM: Glycosylation of proteins is altered in cancer cells and distinctive glycan structures are associated with specific cancers, but little is known about the complete glycan profile of particular tumors. In this study, glycomic analysis of squamous cell carcinoma (SCC) of the uterine cervix was performed to search for useful markers. METHODS: A lectin microarray containing 45 lectins with different binding preferences that covered N- and O-linked glycans was coupled with evanescent field-activated fluorescent detection for glycomic analysis of SCC and normal squamous epithelium (NSE) of the cervix. Formalin-fixed, paraffin-embedded tissue specimens were obtained from 16 patients with uterine cervical cancer. Sections that included both tumor and non-tumor tissues were examined to detect alterations of glycans based on the lectin-binding pattern. RESULTS: Hippeastrum hybrid lectin was found to be a sensitive marker for distinguishing SCC of the cervix from NSE. It was the best lectin for discriminating SCC from other tissues according to receiver-operator curve analysis, as it showed a high sensitivity (81.8%), a high specificity (70.1%), and a large area under the curve (0.8182). Histochemistry confirmed specific cytoplasmic staining of SCC cells by Hippeastrum hybrid lectin, while there was little staining of cervical intraepithelial neoplasia and no staining of NSE. CONCLUSION: The present lectin microarray technique could be applied for tissue-based glycomic analysis of various tumors and for discovery of glycan-related biomarkers.

A Scoring System to Determine Risk of Delayed Bleeding After Endoscopic Mucosal Resection of Large Colorectal Lesions.

BACKGROUND & AIMS: After endoscopic mucosal resection (EMR) of colorectal lesions, delayed bleeding is the most common serious complication, but there are no guidelines for its prevention. We aimed to identify risk factors associated with delayed bleeding that required medical attention after discharge until day 15 and develop a scoring system to identify patients at risk. METHODS: We performed a prospective study of 1214 consecutive patients with nonpedunculated colorectal lesions 20 mm or larger treated by EMR (n = 1255) at 23 hospitals in Spain, from February 2013 through February 2015. Patients were examined 15 days after the procedure, and medical data were collected. We used the data to create a delayed bleeding scoring system, and assigned a weight to each risk factor based on the ß parameter from multivariate logistic regression analysis. Patients were classified as being at low, average, or high risk for delayed bleeding. RESULTS: Delayed bleeding occurred in 46 cases (3.7%, 95% confidence interval, 2.7%-4.9%). In multivariate analysis, factors associated with delayed bleeding included age ≥75 years (odds ratio [OR], 2.36; P < .01), American Society of Anesthesiologist classification scores of III or IV (OR, 1.90; P ≤ .05), aspirin use during EMR (OR, 3.16; P < .05), right-sided lesions (OR, 4.86; P < .01), lesion size ≥40 mm (OR, 1.91; P ≤ .05), and a mucosal gap not closed by hemoclips (OR, 3.63; P ≤ .01). We developed a risk scoring system based on these 6 variables that assigned patients to the low-risk (score, 0-3), average-risk (score, 4-7), or high-risk (score, 8-10) categories with a receiver operating characteristic curve of 0.77 (95% confidence interval, 0.70-0.83). In these groups, the probabilities of delayed bleeding were 0.6%, 5.5%, and 40%, respectively. CONCLUSIONS: The risk of delayed bleeding after EMR of large colorectal lesions is 3.7%. We developed a risk scoring system based on 6 factors that determined the risk for delayed bleeding (receiver operating characteristic curve, 0.77). The factors most strongly associated with delayed bleeding were right-sided lesions, aspirin use, and mucosal defects not closed by hemoclips. Patients considered to be high risk (score, 8-10) had a 40% probability of delayed bleeding.

Incidence of advanced neoplasia during surveillance in high- and intermediate-risk groups of the European colorectal cancer screening guidelines.

Background and study aims: The European guidelines for quality assurance in colorectal cancer (CRC) screening have established high-risk (≥ 5 adenomas or an adenoma ≥ 20 mm) and intermediate-risk (3 - 4 adenomas or at least one adenoma 10 - 19 mm in size, or villous histology, or high grade dysplasia) groups with different endoscopic surveillance intervals. The aim of this study was to evaluate the difference in the incidence of advanced neoplasia (advanced adenoma or CRC) between the two risk groups. Patients and methods: This retrospective group study included patients meeting high- or intermediate-risk criteria for adenomas detected in CRC screening programs and the COLONPREV study before European guidelines were adopted in Spain (June 2011) with a 3-year surveillance recommendation according to Spanish guidelines. The primary outcome measure was the incidence of advanced neoplasia in patients undergoing surveillance. The secondary outcome measure was the CRC incidence. We used an adjusted proportional hazards regression model to control confounding variables. Results: The study included 5401 patients (3379 intermediate risk, 2022 high risk). Endoscopic surveillance was performed in 65.5 % of the patients (2.8 ±â€Š1 years). The incidence of advanced neoplasia in the high- and intermediate-risk groups was 16.0 % (59.0 cases/1000 patient-years) and 12.3 % (41.2 cases/1000 patient-years), respectively. The CRC incidence was 0.5 % (1.4 cases/1000 patient-years) and 0.4 % (1 case/1000 patient-years), respectively. The advanced neoplasia and CRC attributable risk to the high risk group was of 3.7 % and 0.1 %, respectively. In the proportional hazards analysis, the risk of advanced neoplasia was greater in the high-risk group (hazard ratio [HR] 1.5, 95 % confidence interval [CI] 1.2 - 1.8), with no significant differences in the CRC incidence (HR 1.6, 95 %CI 0.6 - 3.8). Conclusions: Patients meeting high-risk criteria have a higher incidence of advanced neoplasia during endoscopic surveillance. No differences were found in the CRC incidence at a 3-year surveillance recommendation.

Endoscopist characteristics that influence the quality of colonoscopy.

BACKGROUND AND STUDY AIM: Several factors have been shown to be related to colonoscopy quality; however, little is known about the effects of endoscopist factors. This study analyzed the influence of endoscopist-related characteristics on quality indicators for colonoscopy. PATIENTS AND METHODS: The study included 48 endoscopists who each performed at least 20 colonoscopies in the colonoscopy arm of a randomized controlled trial comparing fecal immunochemical test vs. colonoscopy in colorectal cancer screening. These endoscopists performed a total of 3838 procedures in the trial. The following were calculated for each endoscopist: adenoma detection rate (ADR), advanced ADR, proximal ADR, distal ADR, and adenoma per colonoscopy rate (APCR). The characteristics of endoscopists were assessed with regard to colonoscopy quality using multivariate regression analysis. Endoscopist characteristics included age, sex, exclusive endoscopy practice, years as a physician, years as a specialist, specialty, total (life-long) number of colonoscopies performed, annual colonoscopy volume, number of hours/week dedicated to endoscopy and number of educational activities in the previous year. RESULTS: Factors associated with ADR were age of the endoscopist (odds ratio [OR] 1.11, 95 % confidence interval [CI] 1.01 - 1.21; P = 0.01) and life-long number of colonoscopies (OR 1.06, 95 %CI 1.01 - 1.11; P = 0.01). Only exclusive dedication to endoscopy practice was found to be independently related to proximal ADR (OR 1.71, 95 %CI 1.15 - 2.74; P = 0.001). Life-long number of colonoscopies was independently related to detection of distal adenomas (OR 1.07, 95 %CI 1.01 - 1.13; P = 0.01). None of the analyzed endoscopist characteristics was associated with advanced ADR or APCR. CONCLUSIONS: This study found that the experience of the endoscopist and exclusive dedication to endoscopy practice, but not annual colonoscopy volume, were associated with better colonoscopy quality.

Surveillance colonoscopy after endoscopic treatment for colorectal neoplasia: From the standpoint of the Asia-Pacific region.

Colonoscopy is considered the gold standard to detect and remove colorectal neoplasia. The efficacy of colonoscopy with polypectomy to reduce colorectal cancer incidence and mortality has been demonstrated. Recently, post-polypectomy surveillance colonoscopy has become a necessary intervention in daily practice not only in Western countries but also in the Asia-Pacific region. Therefore, it is crucial to establish new clinical practice guidelines to reduce the number of unnecessary surveillance colonoscopies in order to create space for screening colonoscopy. The Asia-Pacific Consensus group recommended that surveillance colonoscopy interval should be tailored according to risk level of index colonoscopy. However, precise guidelines on interval of surveillance cannot be given because of a lack of prospective data. According to Korean and Australian guidelines, surveillance intervals after index colonoscopy of 5 years for low-risk subjects and 3 years for high-risk subjects are recommended in Asia-Pacific regions at present. Prospective data including long-term outcomes from the Japan Polyp Study, which is a multicenter randomized control trial, would be useful to establish the Asia-Pacific consensus in the near future.