Cost-Utility Analysis for Colorectal Cancer Screening According to the Initiating Age of National Cancer Screening Program in Korea.

BACKGROUND: This study aimed to identify the most cost-effective strategy for colorectal cancer screening using the fecal immunochemical test (FIT), focusing on screening initiation age in Korea. METHODS: We designed Markov simulation models targeting individuals aged 40 years or older. Twelve strategies combining screening initiation ages (40, 45, or 50 years old), termination ages (80 or no limit), and intervals (1 or 2 years) were modeled, and the most cost-effective strategy was selected. The robustness of the results was confirmed using one-way and probabilistic sensitivity analyses. Furthermore, the cost-effectiveness of the qualitative and quantitative FIT methods was verified using scenario analysis. RESULTS: The 2-year interval strategy with a screening age range of 45-80 years was the most cost-effective (incremental cost-utility ratio = KRW 7,281,646/quality adjusted life years). The most sensitive variables in the results were transition rate from advanced adenoma to local cancer and discount rate. The uncertainty in the model was substantially low. Moreover, strategies starting at the age of 40 years were also cost-effective but considered suboptimal. The scenario analysis showed that there was no significant difference in cost-effectiveness between strategies with various relative screening ratio of quantitative and qualitative method. CONCLUSION: The screening method for advancing the initiation age, as presented in the 2015 revised national screening recommendations, was superior regarding cost-effectiveness. This study provides a new paradigm for the development of a national cancer screening system in Korea, which can be utilized as a scientific basis for economic evaluations.

Effects of prior endoscopic resection on recurrence in patients with T1 colorectal cancer who underwent radical surgery.

PURPOSE: Endoscopic resection (ER) is a reliable treatment for early colorectal cancer without lymph node metastasis. We aimed to examine the effects of ER performed prior to T1 colorectal cancer (T1 CRC) surgery by comparing long-term survival after radical surgery with prior ER to that after radical surgery alone. METHODS: This retrospective study included patients who underwent surgical resection of T1 CRC at the National Cancer Center, Korea, between 2003 and 2017. All eligible patients (n = 543) were divided into primary and secondary surgery groups. To ensure similar characteristics between the groups, 1:1 propensity score matching was used. Baseline characteristics, gross and histological features, along with postoperative recurrence-free survival (RFS) between the two groups were compared. Cox proportional hazard model was used to identify the risk factors affecting recurrence after surgery. Cost analysis was performed to examine the cost-effectiveness of ER and radical surgeries. RESULTS: No significant differences were observed in 5-year RFS between the two groups in matched data (96.9% vs. 95.5%, p = 0.596) and in the unadjusted model (97.2% vs. 96.8%, p = 0.930). This difference was also similar in subgroup analyses based on node status and high-risk histologic features. ER before surgery did not increase the medical costs of radical surgery. CONCLUSION: ER prior to radical surgery did not affect the long-term oncologic outcomes of T1 CRC or significantly increased the medical costs. Attempting ER first for suspected T1 CRC would be a good strategy to avoid unnecessary surgery without concerns of worsening cancer-related prognosis.

Safety and feasibility of single-port surgery for posterior retroperitoneal adrenalectomy using the da Vinci SP robotic system: a retrospective cohort study.

BACKGROUND: This study demonstrates our experience of single-port robotic posterior retroperitoneal adrenalectomy (RPRA) using the da Vinci SP robot system and evaluates its technical feasibility and surgical outcomes. METHODS: We conducted a retrospective analysis of 250 RPRAs, including 117 conventional 3-port RPRAs, 103 reduced 2-port RPRAs, and 30 single-port RPRAs. Each RPRA type was compared by analyzing 30 patients in the early phase of surgery. RESULTS: All patients who underwent single-port RPRA showed excellent surgical outcomes. Age, sex, BMI, and tumor location site did not significantly differ between the three groups. In the early phase, the size of the adrenal tumor was similar between three groups, and it tended to increase as the number of ports increased (p < 0.001). The mean operation time was shorter for patients who underwent single-port RPRA than those who underwent RPRA types (p < 0.001). The numeric rating scale score did not significantly differ between the groups on most days. No major complications were observed, and no patients were converted to open surgery or required additional port insertion. CONCLUSION: Single-port RPA using the da Vinci SP robotic system showed the effectiveness of the surgical procedure and improved cosmetic outcomes for patients, while also enabling surgeons to perform operations with greater ease and convenience. Therefore, single-port RPRA could be a good alternative option for the treatment of adrenal tumors in selected situations.

Comparison of endoscopic submucosal dissection and transanal endoscopic microsurgery for T1 rectal neuroendocrine tumors: a propensity score-matched study.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are the most effective endoscopic resection methods for T1 rectal neuroendocrine tumors (NETs). We aimed to compare the efficacy and safety of ESD and TEM for rectal NETs ≤20 mm. METHODS: Patients with rectal NETs ≤20 mm who underwent ESD or TEM were enrolled in this retrospective observational study. ESD and TEM groups were matched for pathologic tumor size and EMR history. We evaluated between-group differences in R0 resection rate, adverse event rate, procedure time, and hospital stay. RESULTS: We included 285 patients (ESD = 226, TEM = 59) in the final cohort, with 104 patients in the matched groups (ESD = 52, TEM = 52). The R0 resection rate was significantly higher for TEM (ESD 71.2% vs TEM 92.3%, P = .005). However, the median procedure time (ESD 22 [range, 11-65] vs TEM 35 [17-160] minutes, P < .001) and hospital stay (ESD 2.5 range 1-5] vs TEM 4 [3-8] days, P < .001) were significantly shorter for ESD. In the subgroup analysis of patients divided by tumor size <10 mm (ESD = 218, TEM = 49) and 10 to 20 mm (ESD = 8, TEM = 10)], there was no significant between-group difference in the R0 resection rate (83.5% vs 93.9%, P = .063 and 37.5% vs 80%, P = .145, respectively) or the rate of recurrence. CONCLUSIONS: Although TEM showed a better overall R0 resection rate for rectal NETs ≤20 mm, ESD could be a viable treatment modality concerning adverse events, procedure time, and hospital stay for rectal NETs <10 mm with similar R0 resection rates in comparison with TEM.

Korean colonoscopy screening pilot study (K-cospi) for screening colorectal cancer: study protocol for the multicenter, community-based clinical trial.

BACKGROUND: The Korean National Cancer Screening Program has been providing annual fecal immunochemical test for colorectal cancer (CRC) to adults aged 50 years and older since 2004. The Korean Colonoscopy Screening Pilot Study was developed to evaluate the effectiveness of colonoscopy screening for CRC incidence and mortality, screening-related complications, and acceptability of colonoscopy as a primary modality for the national CRC screening program. METHODS: This study and its protocols have been approved by the Korean Public Institutional Review Board and the National Cancer Center Institutional Review Board. We obtain written informed consent from all participants. The target population is males and females aged 50-74 years living within the pilot sites. A total of 26,640 participants will be recruited for colonoscopy screening. Subjects who have been diagnosed with CRC, who are currently undergoing treatment for CRC, or who have undergone colonoscopy screening within the past 5 years are not allowed to participate. All participants need to complete baseline questionnaires. This pilot study is currently conducted by 104 endoscopists from 57 national cancer screening institutions (42 primary, 10 secondary, and 5 tertiary institutions) located in Goyang-si, Gimpo-si, and Paju-si. The number of endoscopists, medical institutions, and districts participating in the pilot study will be expanded, if necessary. Participating endoscopists at each medical institution perform colonoscopy and report the colonoscopy results to a centralized electronic case report system. We conduct a telephone survey after 7 days and 4 weeks post-colonoscopy to assess for procedure-related complications and satisfaction of the participants. In case of abnormal findings from colonoscopy screening, we track the results from follow-up diagnostic tests. Data from this pilot study will be linked to the diagnostic workup results, the Korean Cancer Registry, and death certificate data for analysis of the performance, long-term effects, and cost-effectiveness of colonoscopy. DISCUSSION: The results will provide critical information to determine whether the introduction of colonoscopy as the primary modality of the Korean National Cancer Screening Program would be acceptable and feasible. Trial registration Korean Clinical Research Information Service registry, KCT0004142. Registered on 15 July 2019, http://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=16227.

The relationships between systemic cytokine profiles and inflammatory markers in colorectal cancer and the prognostic significance of these parameters.

BACKGROUND: Immunomodulatory cytokines and systemic inflammatory markers are important during cancer development and progression. This study investigated the association and prognostic impact of systemic cytokine profiles and inflammatory markers in colorectal cancer (CRC). METHODS: Interleukin (IL)-1ß, IL-6, IL-8, IL-9, IL-10, tumour necrosis factor (TNF)-α and vascular endothelial growth factor (VEGF) serum levels were measured using multiplex bead assays in CRC patients. Data on systemic inflammatory markers, such as the modified Glasgow prognostic score (mGPS), the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), prognostic nutritional index (PNI) and fibrinogen, were collected. Survival analysis was performed to identify factors associated with progression-free survival (PFS) and overall survival (OS). RESULTS: There were moderate-to-strong correlations within serum cytokines, as well as within systemic inflammatory markers, whereas the associations between serum cytokines and systemic inflammatory markers were generally weak. IL-8 and the LMR were independent significant prognostic factors for PFS and OS. The low IL-8 and high LMR group had the best survival (both PFS and OS) of all groups. CONCLUSIONS: Systemic cytokine profiles and inflammatory markers have relatively weak intergroup correlations. A composite classification of systemic cytokine profiles and inflammatory markers has an enhanced prognostic value in CRC.

Analysis of metachronous colorectal neoplasms and survival following segmental or extended resection in patients with hereditary non-polyposis colorectal cancer.

PURPOSE: The high incidence of metachronous colorectal tumours in patients with hereditary non-polyposis colorectal cancer (HNPCC) encourages extended resection (ER); however, the optimal surgical approach remains unclear. We evaluated the incidences of metachronous colorectal neoplasms following curative colorectal cancer segmental resection (SR) vs ER in patients with HNPCC and investigated patients' oncologic outcomes according to surgical modality and mismatch repair status. METHODS: We retrospectively investigated medical records of patients with HNPCC (per the Amsterdam II criteria) treated for primary colon cancer at our institution between 2001 and 2017. All patients underwent intensive endoscopic surveillance. RESULTS: We included 87 patients (36 who underwent SR and 51 who underwent ER). The cumulative incidence of metachronous adenoma was higher in the SR group. One patient in the SR group (2.8%) and 3 in the ER group (5.9%) developed metachronous colon cancer; the difference was not significant (P = 0.693). Four patients in the SR group (11.1%) and 1 in the ER group (2.0%) developed distant recurrences; again, the difference was not significant (P = 0.155). Moreover, no significant differences were observed in the 5-year overall survival rates of patients in the SR and ER groups (88.2% vs 95.5%, P = 0.446); the same was true for 5-year disease-free survival rates (79.5% vs 91.0%, P = 0.147). CONCLUSION: The incidence of metachronous cancer was not significantly different between the ER and SR groups; however, that of cumulative metachronous adenoma was higher in the SR group. Hence, intensive surveillance colonoscopy may be sufficient for patients with HNPCC after non-extensive colon resection.

Preoperative endoscopic clipping for rectal tumor localization in laparoscopic anterior resection.

Background: Increasing the number of rectal tumors undergoing preoperative chemoradiotherapy or endoscopic resection has increased the importance of accurate tumor localization. This study describes the preoperative endoscopic clipping method for the localization of rectal tumors and evaluated the feasibility of this technique.Material and methods: A total of 109 patients underwent preoperative endoscopic clipping to localize non-palpable rectal adenocarcinomas, which were located within 10 cm from the anal verge. Two endoscopic clips were attached to both lateral sides of the tumor's distal edge. For confirming the distal margin of tumors during surgery, attempts were made to palpate the clips by digital rectal examination.Results: In all 109 cases, endoscopic clips applied to targeted rectal lesions were easily palpable in the operating room. None of the tumors showed involvement at the distal resection margins (median 1.5 cm) in histopathology.Conclusion: Preoperative endoscopic clipping methods can be useful for localizing non-palpable rectal tumors.

Risk of Interval Cancer in Fecal Immunochemical Test Screening Significantly Higher During the Summer Months: Results from the National Cancer Screening Program in Korea.

OBJECTIVES: This study aimed to evaluate the impact of seasonal variations in climate on the performance of the fecal immunochemical test (FIT) in screening for colorectal cancer in the National Cancer Screening Program in Korea. METHODS: Data were extracted from the National Cancer Screening Program databases for participants who underwent FIT between 2009 and 2010. We compared positivity rates, cancer detection rates, interval cancer rates, positive predictive value, sensitivity, and specificity for FIT during the spring, summer, fall, and winter seasons in Korea. RESULTS: In total, 4,788,104 FIT results were analyzed. FIT positivity rate was lowest during the summer months. In the summer, the positive predictive value of FIT was about 1.1 times (adjusted odds ratio (aOR) 1.08, 95% confidence interval (CI) 1.00-1.16) higher in the overall FIT group and about 1.3 times (aOR 1.29, 95% CI 1.10-1.50) higher in the quantitative FIT group, compared to those in the other seasons. Cancer detection rates, however, were similar regardless of season. Interval cancer risk was significantly higher in the summer for both the overall FIT group (aOR 1.16, 95% CI 1.07-1.27) and the quantitative FIT group (aOR 1.31, 95% CI 1.12-1.52). In addition, interval cancers in the rectum and distal colon were more frequently detected in the summer and autumn than in the winter. CONCLUSIONS: The positivity rate of FIT was lower in the summer, and the performance of the FIT screening program was influenced by seasonal variations in Korea. These results suggest that more efforts to reduce interval cancer during the summer are needed in population-based screening programs using FIT, particularly in countries with high ambient temperatures.

Risk of recurrence after endoscopic resection of early colorectal cancer with positive margins.

BACKGROUND AND STUDY AIM: Additional surgery is recommended if an endoscopically resected T1 colorectal cancer (CRC) specimen shows a positive resection margin. We aimed to investigate the significance of a positive resection margin in endoscopically resected T1 CRC. PATIENTS AND METHODS: We enrolled 265 patients with T1 CRC who underwent endoscopic resection between January 2001 and December 2016. The inclusion criteria were: 1) complete resection by endoscopy, and 2) pathology of a positive margin. Among the 265 patients, 213 underwent additional surgery and 52 did not. In the additional surgery group, various clinicopathological factors were evaluated with respect to the presence or absence of residual tumor. The follow-up results were assessed in the group that did not undergo additional surgery. RESULTS: In the 213 patients who underwent additional surgery, residual tumor was detected in 13 patients (6.1 %), and none of the clinicopathological factors was significantly associated with the presence of residual tumor. Among the 52 patients who did not undergo additional surgery, recurrence was detected in 4 (7.7 %), and all 4 underwent salvage surgery. Among these four patients, three had no risk factors for lymph node metastasis and recurrence was at the previous resection site; pathology was high grade dysplasia, rpT3N0M0, and rpT1N0M0, respectively. CONCLUSIONS: A positive resection margin in endoscopically resected T1 CRC is related to a relatively low incidence of residual tumor (6.1 %). Although current guidelines recommend additional surgery for such cases, surveillance and timely salvage surgery could be another option in selected cases.

Risk Factors Associated With Incomplete Colonoscopy Based on the Analysis of Computed Tomographic Colonography Findings.

OBJECTIVE: This study aimed to identify the computed tomographic colonography (CTC) findings of incomplete colonoscopy compared with those of complete colonoscopy. METHODS: The clinical data and CTC imaging data from January 2004 to December 2012 were retrospectively obtained at 2 different institutions and reviewed by the central review system. A total of 71 patients who underwent both videocolonoscopy and CTC were included in this study. The CTC findings and clinical data were evaluated for the completeness of colonoscopy. RESULTS: In the CTC analysis, differences in total colon length, abdominal circumference, and sigmoid colon diameter were statistically significant between both groups (P < 0.05). Body mass index (BMI) and height were identified as significant clinical factors influencing the completeness of colonoscopy. In multiple logistic regression tests, only BMI and sigmoid colon diameter were independent factors (P < 0.05). CONCLUSIONS: High BMI larger diameter of sigmoid colon was associated with incomplete colonoscopy based on CTC.

Helicobacter pylori infection is an independent risk factor for colonic adenomatous neoplasms.

PURPOSE: Helicobacter pylori infection is considered to have a positive association with colorectal neoplasms. In this study, we evaluated the association between H. pylori infection and colorectal adenomas, based on the characteristics of these adenomas in Korea, where the prevalence of H. pylori infection is high and the incidence of colorectal cancer continues to increase. METHODS: The study cohort consisted of 4,466 subjects who underwent colonoscopy and esophagogastroduodenoscopy during screening (1,245 colorectal adenomas vs. 3,221 polyp-free controls). We compared the rate of H. pylori infection between patients with adenoma and polyp-free control cases, using multivariable logistic regression analysis. RESULTS: The overall rate of positive H. pylori infection was higher in adenoma cases than in polyp-free control cases (55.0 vs. 48.5%, p < 0.001). The odds ratio (OR) of positive H. pylori infection in patients with adenoma compared to polyp-free controls was 1.28 (95% CI 1.11-1.47). The positive association of H. pylori infection with colorectal adenomas was more prominent in advanced adenomas (OR 1.84, 95% CI 1.25-2.70) and multiple adenomas (OR 1.72, 95% CI 1.26-2.35). Based on the location of these adenomas, the OR was significant only in patients with colonic adenomas (OR 1.31, 95% CI 1.13-1.52) and not in those with rectal adenoma (OR 0.85, 95% CI 0.58-1.24). CONCLUSION: Helicobacter pylori infection is an independent risk factor for colonic adenomas, especially in cases of advanced or multiple adenomas, but not for rectal adenomas.

Visceral Adipose Tissue Volume and the Occurrence of Colorectal Adenoma in Follow-up Colonoscopy for Screening and Surveillance.

Whether obesity accelerates adenoma recurrence is not yet clear; therefore, we analyzed the risk factors for adenoma occurrence at follow-up colonoscopy, with a focus on visceral adiposity. In total, 1516 subjects underwent index colonoscopy, computed tomography, and questionnaire assessment from February to May 2008; 539 subjects underwent follow-up colonoscopy at the National Cancer Center at least 6 mo after the index colonoscopy. The relationships between the presence of adenoma at follow-up colonoscopy and anthropometric obesity measurements, including body mass index (BMI), waist circumference (WC), visceral adipose tissue (VAT) volume, and subcutaneous adipose tissue (SAT) volume, were analyzed. 188 (34.9%) had adenomatous polyps at follow-up colonoscopy. Multivariate analysis revealed that VAT volume ≥ 1000 cm3 and BMI ≥ 30 kg/m2 were related to the presence of adenoma at follow-up colonoscopy (VAT volume 1000-1500 cm3: odds ratio [OR] = 2.13(95% confidence interval, CI = 1.06-4.26), P = 0.034; VAT volume ≥ 1000 cm3: OR = 2.24(95% CI = 1.03-4.88), P = 0.043; BMI ≥ 30 kg/m2: OR = 4.22(95% CI = 1.12-15.93), P = 0.034). In contrast, BMI 25-29.9 kg/m2, SAT volume, and WC were not associated with the presence of adenoma at follow-up colonoscopy. In conclusion, excess VAT can contribute to the development and growth of new colorectal adenomas, and is a better predictor of colorectal adenoma occurrence at follow-up colonoscopy than BMI, WC, and SAT volume.

Comparative Evaluation of the Efficacy of Polyethylene Glycol With Ascorbic Acid and an Oral Sulfate Solution in a Split Method for Bowel Preparation: A Randomized, Multicenter Phase III Clinical Trial.

BACKGROUND: An adequate level of bowel preparation before colonoscopy is important. The ideal agent for bowel preparation should be effective and tolerable. OBJECTIVE: The purpose of this study was to compare the clinical efficacy and tolerability of polyethylene glycol with ascorbic acid and oral sulfate solution in a split method for bowel preparation. DESIGN: This was a prospective, multicenter, randomized controlled clinical trial. SETTINGS: Outpatients at the specialized clinics were included. PATIENTS: A total of 186 subjects were randomly assigned. After exclusions, 84 subjects in the polyethylene glycol with ascorbic acid group and 83 subjects in the oral sulfate solution group completed the study and were analyzed. INTERVENTIONS: Polyethylene glycol with ascorbic acid or oral sulfate solution in a split method was the included intervention. MAIN OUTCOME MEASURES: The primary end point was the rate of successful bowel preparation, which was defined as being excellent or good on the Aronchick scale. Tolerability and adverse events were also measured. RESULTS: Success of bowel preparation was not different between 2 groups (91.7% vs 96.4%; p = 0.20), and the rate of adverse GI events (abdominal distension, pain, nausea, vomiting, or abdominal discomfort) was not significantly different between the 2 groups. In contrast, the mean intensity of vomiting was higher in the oral sulfate solution group than in the polyethylene glycol with ascorbic acid group (1.6 ± 0.9 vs 1.9 ± 1.1; p = 0.02). LIMITATIONS: All of the colonoscopies were performed in the morning, and the subjects were offered enhanced instructions for bowel preparation. In addition, the results of tolerability and adverse effect may have a type II error, because the number of cases was calculated for confirming the efficacy of bowel preparation. CONCLUSIONS: Oral sulfate solution is effective at colonoscopy cleansing and has acceptable tolerability when it is compared with polyethylene glycol with ascorbic acid. The taste and flavor of oral sulfate solution still need to be improved to enhance tolerability.

Endoscopic Resection of Cecal Polyps Involving the Appendiceal Orifice: A KASID Multicenter Study.

BACKGROUND: Endoscopic resection of polyps located at the appendiceal orifice (AO) is challenging, and the feasibility and outcomes of endoscopic resection for cecal polyps involving AO are unconfirmed. AIMS: We evaluated the feasibility and outcomes of endoscopic resection for cecal polyps involving AO. METHODS: In this retrospective, multicenter study involving nine tertiary referral centers, we evaluated 131 patients who underwent endoscopic resection for cecal polyps involving AO. RESULTS: The median size of polyps resected was 10 mm (range 3-60 mm). Endoscopic mucosal resection, endoscopic piecemeal mucosal resection, and endoscopic submucosal dissection were performed in 75 (57.3%), 31 (23.7%), and 5 (3.8%) patients, respectively. The en bloc resection rate was 68.7%. Endoscopic complete resection was achieved in 123 lesions (93.9%). Intraprocedural and delayed bleeding occurred in 14 (10.7%) and three patients (2.3%), respectively, and perforation occurred in two patients (1.5%). Seven patients (5.3%) underwent additional surgery because of treatment failure or recurrence. Polyps of ≥20 mm in size showed significantly higher rates of perforation and additional surgery (p < 0.05), and a lower rate of en bloc resection (p < 0.005). Patients with polyps involving ≥75% of AO circumference exhibited a significantly lower rate of en bloc resection (p < 0.001), and significantly higher rates of surgery and recurrence (p < 0.05). Recurrence during follow-up occurred in 12 patients (15.6%); polyps involving ≥75% of AO circumference were an independent risk factor for recurrence. CONCLUSION: Endoscopic resection of cecal polyps involving AO is safe and effective in select patients.

Chemoprevention in gastrointestinal physiology and disease. Targeting the progression of cancer with natural products: a focus on gastrointestinal cancer.

The last decade has witnessed remarkable progress in the utilization of natural products for the prevention and treatment of human cancer. Many agents now in the pipeline for clinical trial testing have evolved from our understanding of how human nutritional patterns account for widespread differences in cancer risk. In this review, we have focused on many of these promising agents arguing that they may provide a new strategy for cancer control: natural products once thought to be only preventive in their mode of action now are being explored for efficacy in tandem with cancer therapeutics. Natural products may reduce off-target toxicity of therapeutics while making cancers more amenable to therapy. On the horizon is the use of certain natural products, in their own right, as mitigants of late-stage cancer, a new frontier for small-molecule natural product drug discovery.

Early Outcomes of Endoscopic Submucosal Dissection for Colorectal Neoplasms According to Clinical Indications.

BACKGROUND: Although endoscopic submucosal dissection has been shown to be safe and effective for colorectal tumors, its clinical outcomes vary. OBJECTIVE: The aim of this study is to assess the outcomes of endoscopic submucosal dissection according to clinical indications. DESIGN: This is a prospective, multicenter, single-arm study. SETTING: The study was conducted at special hospitals for colorectal diseases and cancers. PATIENTS: The study population included consecutive patients aged 20 to 80 years who underwent colorectal endoscopic submucosal dissection for 1) early colorectal cancer, 2) laterally spreading tumors ≥2 cm in diameter, and 3) submucosal tumors. INTERVENTIONS: Procedures were performed by experienced colonoscopists. MAIN OUTCOME MEASURES: The primary end points were en bloc and curative resection rates. En bloc resection was defined as endoscopic one-piece resection without tumor fragmentation. Curative resection was defined as en bloc resection and no pathologic requirement for additional surgery. Secondary end points included procedure time, complications, and hospital stay. RESULTS: Of 321 patients, 317 (98.8%) underwent en bloc resection and 231 (72.0%) underwent curative resection. The mean procedure time was 46.2 minutes. Mean hospital stay after the procedure was 3.1 days. Perforation occurred in 2 patients (0.6%), and bleeding occurred in 10 (3.1%) patients. All patients with complications were treated by endoscopic clipping or nonoperative management. Fifteen patients (4.7%) underwent additional radical surgery owing to the risks of lymph node metastasis. Although tumor size was smaller and procedure time shorter in the submucosal tumor group than in the laterally spreading tumor or early colorectal cancer group, there were no differences in clinical outcomes including en bloc and curative resection rates. Submucosal fibrosis was the only factor affecting endoscopic submucosal dissection procedure-related complications. LIMITATIONS: Early outcomes in a limited population and the potential for selection bias were limitations of this study. CONCLUSIONS: Outcomes of colorectal endoscopic submucosal dissection were acceptable in selected patients, with no difference in outcomes according to clinical indications. Because submucosal fibrosis can increase complications, it should be minimized before endoscopic submucosal dissection.

The role of fibrinogen as a predictor in preoperative chemoradiation for rectal cancer.

BACKGROUND: To perform chemoradiotherapy (CRT) effectively, it is clinically beneficial to identify predictors of tumor response after CRT. This study examined the association between plasma fibrinogen level before preoperative CRT and tumor response in advanced rectal cancer. METHODS: This was a retrospective study of 947 patients who received preoperative CRT followed by curative surgery for primary rectal cancer. We analyzed clinical factors that could be associated with pathologic tumor response in terms of downstaging (ypStage 0-I), primary tumor regression (ypT0-1), and complete response (ypT0N0). RESULTS: Downstaging was observed in 366 patients (38.6%), primary tumor regression in 187 patients (19.7%) and complete response in 138 patients (14.6%). Multivariate analysis found that pre-CRT carcinoembryonic antigen (CEA) level, fibrinogen level, hemoglobin level, clinical T and N classification, distance from anal verge, and histologic grade were significant predictive factors for downstaging; CEA level, fibrinogen level, and N classification predicted primary tumor regression; CEA level, and fibrinogen level were predictive for complete response. CONCLUSIONS: This study demonstrated that fibrinogen level was a significant predictor of pathologic tumor response after preoperative CRT.

Benefits of fresh-frozen plasma as a replacement fluid to neutralize ABO antibodies.

BACKGROUND: ABO-incompatible organ transplantation requires pre-transplant conditioning to reduce ABO antibody levels in the recipients. With respect to replacement fluids used in plasma exchange, we intended to verify whether fresh-frozen plasma (FFP) containing soluble ABO substance (SAS) is more effective than albumin solution in reducing ABO IgG antibody levels. METHODS: Apheresis data were retrospectively studied for in vivo effects, and in vitro plasma mixing studies were prospectively performed. The amount of ABO IgG antibodies bound to red cells was measured as the mean fluorescence intensity (MFI) using flow cytometry. Neutralization of ABO antibodies in the recipientst plasma by an ABO-incompatible donornc plasma was measured using the inhibition assay principle. The MFI value of the unneutralized control tube was divided by that of the neutralized test tube (neutralizing-capacity index, NCI). RESULTS: The plasma exchange procedures replaced with group AB FFP showed a significantly greater decreased titer than those replaced with albumin (P = 0.010). The in vitro plasma mixing study simulating plasma exchange also produced consistent results. When the pooled group O plasma was neutralized for anti-A by individual group AB plasmas (AB-to-O, N = 30), the NCI was 12.8 ± 5.4 (6.5-29.5). When this group O plasma was neutralized by pooled group AB or A plasma, the repeatedly measured NCI (N = 5) of A-to-O (11.4 ± 1.4) was not significantly different from that of AB-to-O (9.7 ± 1.3, P = 0.074). CONCLUSIONS: ABO antibody levels are reduced more effectively by group AB FFP than by albumin. Either group AB or donor type (group A or B) FFP can be infused to group O recipients. FFP units with higher SAS levels can be selected from multiple available candidate units using our protocol for measuring the neutralizing-capacity.

Low-mass-ion discriminant equation: a new concept for colorectal cancer screening.

Blood metabolites can be detected as low-mass ions (LMIs) by mass spectrometry (MS). These LMIs may reflect the pathological changes in metabolism that occur as part of a disease state, such as cancer. We constructed a LMI discriminant equation (LOME) to investigate whether systematic LMI profiling might be applied to cancer screening. LMI information including m/z and mass peak intensity was obtained by five independent MALDI-MS analyses, using 1,127 sera collected from healthy individuals and cancer patients with colorectal cancer (CRC), breast cancer (BRC), gastric cancer (GC) and other types of cancer. Using a two-stage principal component analysis to determine weighting factors for individual LMIs and a two-stage LMI selection procedure, we selected a total of 104 and 23 major LMIs by the LOME algorithms for separating CRC from control and rest of cancer samples, respectively. CRC LOME demonstrated excellent discriminating power in a validation set (sensitivity/specificity: 93.21%/96.47%). Furthermore, in a fecal occult blood test (FOBT) of available validation samples, the discriminating power of CRC LOME was much stronger (sensitivity/specificity: 94.79%/97.96%) than that of the FOBT (sensitivity/specificity: 50.00%/100.0%), which is the standard CRC screening tool. The robust discriminating power of the LOME scheme was reconfirmed in screens for BRC (sensitivity/specificity: 92.45%/96.57%) and GC (sensitivity/specificity: 93.18%/98.85%). Our study demonstrates that LOMEs might be powerful noninvasive diagnostic tools with high sensitivity/specificity in cancer screening. The use of LOMEs could potentially enable screening for multiple diseases (including different types of cancer) from a single sampling of LMI information.