Complete Obstruction, a Real Risk Factor: A Comprehensive Study on Obstruction in Stage IIA Colon Cancer With Propensity Score Matching Analysis.

MICROABSTRACT: This study evaluates the prognostic significance of obstructions in stage IIA colon cancer, distinguishing between partial and complete obstructions. It employs a retrospective review of 1914 patients with propensity score matching to analyze oncologic outcomes. Findings reveal complete obstruction as a significant risk factor for poorer outcomes, emphasizing the necessity for further research to refine treatment strategies, particularly regarding the efficacy of adjuvant chemotherapy across obstruction types. BACKGROUND: This study examined the prognostic impact of obstructions in stage IIA colon cancer. The analysis specifically differentiated partial and complete obstructions, analyzing their distinct influences of both on oncologic outcomes. MATERIALS AND METHODS: A retrospective review was conducted of stage IIA colon cancer cases with the presence of an obstruction. Patients were stratified by whether it was partial or complete based on the severity of obstruction. Propensity score matching was employed to control for confounders. RESULTS: Among 1914 consecutive patients diagnosed with stage IIA colon cancer, 758 patients (597 patients with partial obstruction, 161 patients with complete obstruction) exhibited obstruction, while 1156 patients had no obstruction. The median follow-up period was 126 months. Complete obstruction was associated with poorer disease-free survival (Hazard ratio (HR) = 1.785, P < .001) and overall survival (HR = 1.853, P = .001). This trend persisted after propensity score matching, patients with complete obstruction showing a worsened disease-free survival (HR = 1.666, P = .028) and overall survival (HR = 1.732, P = .041). Adjuvant chemotherapy showed improved outcomes overall, but its efficacy varied across obstruction types. CONCLUSION: Differentiating between complete and partial obstructions in stage IIA colon cancer is an important clinical distinction, as our findings suggest that complete obstruction is a significant risk factor for poorer oncologic outcomes. While adjuvant chemotherapy generally improves prognosis in stage IIA colon cancer, the correlation of obstruction type with its efficacy remains uncertain, necessitating further research to refine treatment strategies.

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn's disease.

BACKGROUND: Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn's disease (CD). Anti-tumor necrotic factor (TNF) therapy combined with drainage procedure is effective as well. However, previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure. AIM: This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn's perianal fistula (CPF) closure rates after stem cell transplantation with and without anti-TNF therapy, and to identify the factors affecting CPF closure and recurrence. METHODS: The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled. Clinical data were compared according to anti-TNF therapy and CPF closure. RESULTS: A total of 65 patients were included. The median age of females was 26 years (range: 21-31) and that of males was 29 (44.6%). The mean follow-up duration was 65.88 ± 32.65 months, and complete closure was observed in 50 (76.9%) patients. The closure rates were similar after stem cell transplantation with and without anti-TNF therapy (66.7% vs 81.6% at 3 year, P = 0.098). The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture (P = 0.027, 0.002, and 0.008, respectively). Clinical factors such as complexity, number of fistulas, presence of concurrent abscess, and medication were not significant for closure. The cumulative 1-, 2-, and 3-year closure rates were 66.2%, 73.8%, and 75.4%, respectively. CONCLUSION: Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation. However, both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy. Fistulous tract length, proctitis, and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

Short- and long-term outcomes of surgical treatment in patients with intestinal Behcet's disease.

BACKGROUND: Behcet's disease (BD), a chronic vasculitic disorder affecting multiple organs, is characterized by recurrent oral and genital ulcers, arthritis, vasculitis, and intestinal ulcers. Although intestinal involvement of BD is common in East Asia, the efficacy and long-term outcomes of surgical treatment of intestinal BD still remain to be established. AIM: To evaluate the postoperative clinical course of intestinal BD and determine factors associated with its recurrence. METHODS: Data from patients who underwent surgical treatment for intestinal BD between January 2010 and August 2021 were retrospectively reviewed. Patients' demographics, clinical features, postoperative course, complications, and follow-up data were evaluated. RESULTS: We analyzed 39 surgeries in 31 patients. The mean patient age was 45.1 years, and the mean interval between the diagnosis of intestinal BD and surgical treatment was 4.9 years (range 1.0-8.0 years). The most common indication for surgery was medical intractability (n = 16, 41.0%), followed by fistula or abscess (n = 11, 28.2%). Laparoscopic approaches were used in 19 patients (48.7%), and 5 patients (12.8%) underwent emergency surgeries. The most common surgical procedure was ileocecal resection (n = 18, 46.2%), followed by right colectomy (n = 11, 28.2%). A diverting stoma was created in only one patient (2.6%). During a mean follow-up period of 45 (range 8-72) months, eight cases (20.5%) of recurrence in five patients required reoperation. The interval between operations was 12.1 months (range 6.3-17.8 mo). Four patients (10.3%) experienced recurrence within 1 year postoperatively, and all eight recurrences occurred within 2 years of the initial surgery. The reoperation rates at 1 and 3 years were 10.3% and 20.5%, respectively. A redo ileocolic anastomosis was performed in all recurrent cases. In multivariate Cox regression analysis, emergency surgery [hazard ratio (HR) 9.357, 95% confidence interval (CI): 1.608-54.453, P = 0.013] and elevated C-reactive protein (CRP) levels (HR 1.154, 95%CI: 1.002-1.328, P = 0.047), but not medication use, were predictors of recurrence. CONCLUSION: Surgical resection is a feasible treatment option for complicated BD. Reoperation is associated with severe inflammatory conditions, reflected by increased CRP levels and the requirement for emergency surgery.

Risk factors for the failure of endoscopic balloon dilation to manage anastomotic stricture from colorectal surgery: retrospective cohort study.

BACKGROUND: An anastomotic stricture after colorectal surgery is principally managed by endoscopic balloon dilation (EBD). Although this intervention is effective, however, subsequent procedures or surgical interventions are often required. This study aimed to assess the long-term outcomes of EBD for anastomotic stricture arising from colorectal cancer surgery. MATERIALS AND METHODS: We analyzed 173 patients who received curative surgery for colorectal cancer at our hospital between January 2000 and December 2022 and had undergone EBD to manage anastomotic stricture. The medical records of these cases were retrospectively reviewed to assess the outcomes and risk factors for restenosis and permanent stoma. RESULTS: Of the 173 study patients, 41 (23.7%) presented with restenosis with a median time to recurrence of 49 [37-150] days. The restenosis group was significantly younger (55.6 years versus 60.8 years), with a more prominent rectal location (80.5% versus 57.6%), a higher incidence of hand-sewn anastomosis (24.4% versus 5.3%), and a higher percentage of neoadjuvant radiotherapy (34.1% versus 5.3%, P < 0.001). Multivariable analysis indicated neoadjuvant radiotherapy (adjusted HR 2.48; 95% CI 1.03-5.95) and cerebral vascular disease (adjusted HR 6.97; 95% CI 2.15-22.54) as independent prognostic factors for restenosis. Fourteen patients (8.1%) required a permanent stoma due to treatment failure. All cases needing a permanent stoma were male (14 patients, 100%, P = 0.007) and this group had a higher rate of neoadjuvant radiotherapy, adjuvant chemotherapy, and hand-sewn anastomosis. CONCLUSION: Patients receiving neoadjuvant radiotherapy are most prone to restenosis after an EBD intervention to manage an anastomotic stricture. Neoadjuvant radiotherapy is also a strong risk factor for requiring a permanent stomas due to treatment failure.

Short-term outcomes of da Vinci SP versus Xi for colon cancer surgery: a propensity-score matching analysis of multicenter cohorts.

Recent advancements in robotic systems have led to the introduction of the da Vinci SP system, which allows surgeons to perform colon cancer surgery through fewer ports. This study aimed to evaluate the perioperative outcomes of colon cancer surgeries conducted using the da Vinci SP and Xi systems. Patients who underwent robotic colon cancer surgeries between November 2020 and December 2022 at two tertiary referral centers were considered for inclusion. Following propensity-score matching, short-term outcomes between the two systems were retrospectively analyzed. Out of 189 patients included in the study, 106 from 53 propensity-score matched pairs were analyzed. Patients operated on with the SP system exhibited smaller incision lengths (5.0 cm vs. 9.4 cm, p < 0.001) experienced less pain at 8 h (3.0 vs. 3.5, p < 0.001) and at 24 h post-operation (2.9 vs. 3.3, p = 0.001) and had a shorter duration of hospital stay (5 days vs. 6 days, p = 0.002). The overall rate of postoperative complications was 10.4%, with no significant difference between the SP and Xi groups (7.5% vs. 13.2%). Robotic-assisted colon cancer surgery using the da Vinci SP system is feasible and demonstrates favorable short-term outcomes. Compared to the Xi system, the SP system offers advantages in terms of cosmesis, postoperative pain, and recovery duration for colon cancer patients.

Deciphering the DNA methylation landscape of colorectal cancer in a Korean cohort.

Aberrant DNA methylation plays a pivotal role in the onset and progression of colorectal cancer (CRC), a disease with high incidence and mortality rates in Korea. Several CRC-associated diagnostic and prognostic methylation markers have been identified; however, due to a lack of comprehensive clinical and methylome data, these markers have not been validated in the Korean population. Therefore, in this study, we aimed to obtain the CRC methylation profile using 172 tumors and 128 adjacent normal colon tissues of Korean patients with CRC. Based on the comparative methylome analysis, we found that hypermethylated positions in the tumor were predominantly concentrated in CpG islands and promoter regions, whereas hypomethylated positions were largely found in the open-sea region, notably distant from the CpG islands. In addition, we stratified patients by applying the CpG island methylator phenotype (CIMP) to the tumor methylome data. This stratification validated previous clinicopathological implications, as tumors with high CIMP signatures were significantly correlated with the proximal colon, higher prevalence of microsatellite instability status, and MLH1 promoter methylation. In conclusion, our extensive methylome analysis and the accompanying dataset offers valuable insights into the utilization of CRC-associated methylation markers in Korean patients, potentially improving CRC diagnosis and prognosis. Furthermore, this study serves as a solid foundation for further investigations into personalized and ethnicity-specific CRC treatments. [BMB Reports 2023; 56(10): 569-574].

Adult-onset megacolon with focal hypoganglionosis: A detailed phenotyping and prospective cohort study.

BACKGROUND: In this prospective cohort study, we evaluated features of "adult-onset megacolon with focal hypoganglionosis." METHODS: We assessed the radiologic, endoscopic, and histopathologic phenotyping and treatment outcomes of 29 patients between 2017 and 2020. Data from community controls, consisting of 19,948 adults undergoing health screenings, were analyzed to identify risk factors. Experts reviewed clinical features and pathological specimens according to the London Classification for gastrointestinal neuromuscular pathology. KEY RESULTS: The median age of the patients with adult-onset megacolon with focal hypoganglionosis at symptom onset was 59 years (range, 32.0-74.9 years), with mean symptom onset only 1 year before diagnosis. All patients had focal stenotic regions with proximal bowel dilatation (mean diameter, 78.8 mm; 95% confidence interval [CI], 72-86). The comparison with community controls showed no obvious risk factors. Ten patients underwent surgery, and all exhibited significant hypoganglionosis: 5.4 myenteric ganglion cells/cm (interquartile range [IQR], 3.7-16.4) in the stenotic regions compared to 278 cells/cm (IQR, 190-338) in the proximal and 95 cells/cm (IQR, 45-213) in the distal colon. Hypoganglionosis was associated with CD3+ T cells along the myenteric plexus. Colectomy was associated with significant symptom improvement compared to medical treatment [change in the Global Bowel Satisfaction score, -5.4 points (surgery) vs. -0.3 points (medical treatment); p < 0.001]. CONCLUSIONS AND INFERENCES: Adult-onset megacolon with focal hypoganglionosis has distinct features characterized by hypoganglionosis due to inflammation. Bowel resection appears to benefit these patients.

Personalised circulating tumour DNA assay with large-scale mutation coverage for sensitive minimal residual disease detection in colorectal cancer.

BACKGROUND: Postoperative minimal residual disease (MRD) detection using circulating-tumour DNA (ctDNA) requires a highly sensitive analysis platform. We have developed a tumour-informed, hybrid-capture ctDNA sequencing MRD assay. METHODS: Personalised target-capture panels for ctDNA detection were designed using individual variants identified in tumour whole-exome sequencing of each patient. MRD status was determined using ultra-high-depth sequencing data of plasma cell-free DNA. The MRD positivity and its association with clinical outcome were analysed in Stage II or III colorectal cancer (CRC). RESULTS: In 98 CRC patients, personalised panels for ctDNA sequencing were built from tumour data, including a median of 185 variants per patient. In silico simulation showed that increasing the number of target variants increases MRD detection sensitivity in low fractions (<0.01%). At postoperative 3-week, 21.4% of patients were positive for MRD by ctDNA. Postoperative positive MRD was strongly associated with poor disease-free survival (DFS) (adjusted hazard ratio 8.40, 95% confidence interval 3.49-20.2). Patients with a negative conversion of MRD after adjuvant therapy showed significantly better DFS (P < 0.001). CONCLUSION: Tumour-informed, hybrid-capture-based ctDNA assay monitoring a large number of patient-specific mutations is a sensitive strategy for MRD detection to predict recurrence in CRC.

Optimal surgical management of duodenal fistula in Crohn's disease: a Korean multicenter cohort study.

PURPOSE: Duodenal fistula in Crohn's disease (CDF) is a rare condition with an unclear optimal surgical management approach. We reviewed a Korean multicenter cohort of CDF surgery cases and assessed their perioperative outcomes to evaluate the effectiveness of the surgical interventions. METHODS: The medical records of patients who underwent CD surgery between January 2006 and December 2021 from three tertiary medical centers were retrospectively reviewed. Only CDF cases were included in this study. The demographic and preoperative characteristics, perioperative details, and postoperative outcomes were analyzed. RESULTS: Among the initial population of 2149 patients who underwent surgery for CD, 23 cases (1.1%) had a CDF operation. Fourteen of these patients (60.9%) had a history of previous abdominal surgery, and 7 had duodenal fistula at the previous anastomosis site. All duodenal fistulas were excised and primarily repaired via a resection of the originating adjacent bowel. Additional procedures such as gastrojejunostomy, pyloric exclusion, or T-tube insertion were performed in 8 patients (34.8%). Eleven patients (47.8%) experienced postoperative complications including for anastomosis leakages. Fistula recurrence was noted in 3 patients (13%) of which one patient required a re-operation. Biologics administration was associated with fewer adverse events by multivariable analysis (P = 0.026, odds ratio = 0.081). CONCLUSION: Optimal perioperative conditioning of patients receiving a primary repair of a fistula and resection of the original diseased bowel can successfully cure CDF. Along with primary repair of the duodenum, other complementary additional procedures should be considered for better postoperative outcomes.

Partial mesorectal excision can be a primary option for middle rectal cancer: a propensity-score matched retrospective analysis.

Purpose: Although partial and total mesorectal excision (PME and TME) is primarily indicated for the upper and lower rectal cancer, respectively, few studies have evaluated whether PME or TME is more optimal for middle rectal cancer. Methods: This study included 671 patients with middle and upper rectal cancer who underwent robot-assisted PME or TME. The 2 groups were optimized by propensity-score matching of sex, age, clinical stage, tumor location, and neoadjuvant treatment. Results: Complete mesorectal excision was achieved in 617 of 671 patients (92.0%), without showing a difference between the PME and TME groups. Local (5.3% vs. 4.3%, P>0.999) and systemic (8.5% vs. 16.0%, P=0.181) recurrence rates also did not differ between the 2 groups, respectively, in patients with middle and upper rectal cancer. The 5-year disease-free survival (81.4% vs. 74.0%, P=0.537) and overall survival (88.0% vs. 81.1%, P=0.847) rates also did not differ between the PME and TME groups, confined to middle rectal cancer. Moreover, 5-year recurrence and survival rates were not affected by distal resection margins of 2 cm (P=0.112) to 4 cm (P>0.999), regardless of pathological stages. Postoperative complication rate was higher in the TME than in the PME group (21.4% vs. 14.5%, P=0.027). Incontinence was independently associated with TME (odds ratio [OR], 2.009; 95% confidence interval, 1.015-3.975; P=0.045), along with older age (OR, 4.366, P<0.001) and prolonged operation time (OR, 2.196; P=0.500). Conclusion: PME can be primarily recommended for patients with middle rectal cancer with lower margin of >5 cm from the anal verge.

Robot-assisted lateral pelvic lymph node dissection in patients with advanced rectal cancer: a single-center experience of 65 cases.

The treatment of lateral pelvic lymph node (LPLN) metastasis of rectal cancer has evolved because of technical difficulties from open surgery to laparoscopy and, recently, robot-assisted surgery. This study aimed to evaluate the technical feasibility and short- and long-term outcomes of robot-assisted LPLN dissection (LPND) following total mesorectal excision (TME) in advanced rectal cancer. Clinical data of 65 patients who underwent robotic-assisted TME with LPND from April 2014 to July 2022 were reviewed. Data regarding operative details, postoperative morbidity (within 90 postoperative days) for short-term outcomes and lateral recurrence as long-term outcomes were analyzed. Among the 65 patients with LPND, preoperative chemoradiotherapy was performed in 49 (75.4%). The mean operative time was 306.8 (range 191-477) min, and the mean time of unilateral LPND was 38.6 (range 16-66) min. LPND was bilaterally performed in 19 (29.2%) patients. The mean number of each side of harvested LPLNs was 6.8. Lymph node metastasis was observed in 15 (23.0%) patients, and 10 (15.4%) patients had postoperative complications. Lymphocele (n = 3) and pelvic abscess (n = 3) were the most common, followed by voiding difficulty, erectile dysfunction, obturator neuropathy, and sciatic neuropathy (all n = 1). During the 25 months of median follow-up, no lateral recurrence of the LPND site was noted. Robot-assisted LPND following TME is safe and feasible and showed acceptable short- and long-term outcomes. Despite some study limitations, we may be able to apply this strategy more widely through subsequent prospective controlled studies.

Can clinicopathologic high-risk features in T3N0 colon cancer be reliable prognostic factors?

Purpose: The purpose of this study was to assess the reliability and prognostic significance of the high-risk feature (HRF) in patients with T3N0 colon cancer. Methods: We included 1,205 patients with pT3N0 colon cancer treated with curative radical resection between 2012 and 2016. HRF was defined as lymphovascular invasion, perineural invasion, poorly/undifferentiated histology, margin involvement, and preoperative obstruction. We investigated the relationships between the number and type of HRF and recurrence-free survival (RFS) and overall survival (OS), as well as the effect of adjuvant treatment. Results: A total of 751 of the patients (62.3%) had more than 1 HRF and 515 of the patients (42.7%) underwent adjuvant treatment. Patients who had more than 2 HRFs had a significantly worse 5-year RFS and OS compared to patients who had neither HRF nor even one HRF. According to the findings of the multivariate analysis, the presence of multiple HRFs was a risk factor for a lower RFS and OS. When the quantity and type of HRF were taken into consideration in the multivariate analysis, adjuvant chemotherapy was not found to be linked with RFS or OS in patients with pT3N0 colon cancer. Conclusion: In the present study, adjuvant treatment based on the current guideline of treatment indication was unable to enhance the prognosis of patients with pT3N0 colon cancer. The role of adjuvant treatment in T3N0 colon cancer must be examined with the HRF count in mind.

Pathologic Implications of Magnetic Resonance Imaging-detected Extramural Venous Invasion of Rectal Cancer.

BACKGROUND: Extramural venous invasion (EMVI) is a poor prognostic factor in rectal cancer. Recent advances in magnetic resonance imaging (MRI) allow for the detection of EMVI before surgery. This study aimed to analyze the correlations between MRI-detected EMVI (MR-EMVI) and pathologic parameters in patients with rectal cancer. MATERIALS AND METHODS: This study retrospectively analyzed 721 patients who underwent radical resection for locally advanced rectal cancer between 2018 and 2019 at the Asan Medical center. All patients underwent an MRI before surgery. The lesions of patients who received neoadjuvant chemoradiation therapy (CRT) were evaluated by MRI before and after the neoadjuvant CRT. RESULTS: Of the 721 patients, 118 (16.4%) showed a positive MR-EMVI, which significantly correlated with advanced pathologic T-category and N-category, extranodal extension, poor differentiation, lymphatic invasion, venous invasion, and perineural invasion. In addition, MR-EMVI was an independent factor for predicting the pathologic nodal status (OR 3.476, 95% CI, 2.186-5.527, P < .001). Patients with a positive MR-EMVI had a sensitivity of 28.0% and specificity of 91.9% for predicting regional lymph node metastasis, whereas the MR-N category had a sensitivity of 88.7% and specificity of 30.6%. Patients whose MR-EMVI changed from positive to negative after neoadjuvant CRT had no significant differences in pathologic parameters except for lymphatic invasion with patients who were negative before and after neoadjuvant CRT. CONCLUSION: MR-EMVI correlated with aggressive pathologic features, which indicated a poor prognosis. MR-EMVI may be a complementary imaging biomarker for predicting nodal status and evaluating tumor response to neoadjuvant CRT.

Efficacy of preoperative chemoradiotherapy in patients with cT2N0 distal rectal cancer.

PURPOSE: This study was designed to determine the feasibility of preoperative chemoradiotherapy (PCRT) in patients with clinical T2N0 distal rectal cancer. METHODS: Patients who underwent surgery for clinical T2N0 distal rectal cancer between January 2008 and December 2016 were included. Patients were divided into PCRT and non-PCRT groups. Non-PCRT patients underwent radical resection or local excision (LE) according to the surgeon's decision, and PCRT patients underwent surgery according to the response to PCRT. Patients received 50.0 to 50.4 gray of preoperative radiotherapy with concurrent chemotherapy. RESULTS: Of 127 patients enrolled, 46 underwent PCRT and 81 did not. The mean distance of lesions from the anal verge was lower in the PCRT group (P=0.004). The most frequent operation was transanal excision and ultralow anterior resection in the PCRT and non-PCRT groups, respectively. Of the 46 patients who underwent PCRT, 21 (45.7%) achieved pathologic complete response, including 15 of the 24 (62.5%) who underwent LE. Rectal sparing rate was significantly higher in the PCRT group (11.1% vs. 52.2%, P<0.001). There were no significant differences in 3- and 5-year overall survival and recurrence-free survival regardless of PCRT or surgical procedures. CONCLUSION: PCRT in clinical T2N0 distal rectal cancer patients increased the rectal sparing rate via LE and showed acceptable oncologic outcomes. PCRT may be a feasible therapeutic option to avoid abdominoperineal resection in clinical T2N0 distal rectal cancer.

FDG metabolic parameter-based models for predicting recurrence after upfront surgery in synchronous colorectal cancer liver metastasis.

OBJECTIVE: This study aimed to develop and validate post- and preoperative models for predicting recurrence after curative-intent surgery using an FDG PET-CT metabolic parameter to improve the prognosis of patients with synchronous colorectal cancer liver metastasis (SCLM). METHODS: In this retrospective multicenter study, consecutive patients with resectable SCLM underwent upfront surgery between 2006 and 2015 (development cohort) and between 2006 and 2017 (validation cohort). In the development cohort, we developed and internally validated the post- and preoperative models using multivariable Cox regression with an FDG metabolic parameter (metastasis-to-primary-tumor uptake ratio [M/P ratio]) and clinicopathological variables as predictors. In the validation cohort, the models were externally validated for discrimination, calibration, and clinical usefulness. Model performance was compared with that of Fong's clinical risk score (FCRS). RESULTS: A total of 374 patients (59.1 ± 10.5 years, 254 men) belonged in the development cohort and 151 (60.3 ± 12.0 years, 94 men) in the validation cohort. The M/P ratio and nine clinicopathological predictors were included in the models. Both postoperative and preoperative models showed significantly higher discrimination than FCRS (p < .05) in the external validation (time-dependent AUC = 0.76 [95% CI 0.68-0.84] and 0.76 [0.68-0.84] vs. 0.65 [0.57-0.74], respectively). Calibration plots and decision curve analysis demonstrated that both models were well calibrated and clinically useful. The developed models are presented as a web-based calculator ( https://cpmodel.shinyapps.io/SCLM/ ) and nomograms. CONCLUSIONS: FDG metabolic parameter-based prognostic models are well-calibrated recurrence prediction models with good discriminative power. They can be used for accurate risk stratification in patients with SCLM. KEY POINTS: • In this multicenter study, we developed and validated prediction models for recurrence in patients with resectable synchronous colorectal cancer liver metastasis using a metabolic parameter from FDG PET-CT. • The developed models showed good predictive performance on external validation, significantly exceeding that of a pre-existing model. • The models may be utilized for accurate patient risk stratification, thereby aiding in therapeutic decision-making.

Lifestyle interventions after colorectal cancer surgery using a mobile digital device: A study protocol for a randomized controlled trial.

BACKGROUND: In treating colorectal cancer, surgical techniques and adjuvant treatments have advanced over the past century, but relatively less attention has been given to improve health-related quality of life (HRQOL). Recent studies report a significant association between cancer recurrence and patient lifestyle after surgery, hence emphasizing the need to assist patients to reduce this risk through appropriate lifestyle choices. The proposed study will evaluate the effects of digital interventions on lifestyle after surgery for colorectal cancer using mobile applications. METHODS: A randomized controlled trial design was proposed. A total of 320 patients diagnosed with colorectal cancer aged between 20 and 70 years were to be enrolled and randomized in equal numbers into 4 groups (3 groups assigned to different mobile applications and a control group). Surveys that evaluate HRQOL, physical measurements, and metabolic parameters (fasting glucose, hemoglobin A1C, triglyceride, high-density lipoprotein cholesterol), and fat/muscle mass measurements by abdominal computed tomography (CT), will be conducted prior to surgery and every 6 months post-surgery for 18 months. Statistical analysis will be used to compare the outcomes between groups. DISCUSSION: Results from this study could provide evidence that easily accessible mobile applications can influence patient lifestyles. Results showing minimal effects of such applications could also be constructive for improving healthcare-related applications.

Cumulative incidence and risk factors for pouch adenomas associated with familial adenomatous polyposis following restorative proctocolectomy.

BACKGROUND: The emergence of restorative total proctocolectomy has significantly reduced the lifetime colorectal cancer risk associated with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch over time and may even progress to carcinoma. We evaluated the cumulative incidence, time to development, and risk factors associated with ileal pouch adenoma. AIM: To evaluate the cumulative incidence, time to development, and risk factors associated with pouch adenoma. METHODS: In this retrospective, observational study conducted at a tertiary center, 95 patients with FAP who underwent restorative proctocolectomy at our center between 1989 and 2018 were consecutively included. The mean follow-up period was 88 mo. RESULTS: Pouch adenomas were found in 24 (25.3%) patients, with a median time of 52 mo to their first formation. Tubular adenomas were detected in most patients (95.9%). There were no high-grade dysplasia or malignancies. Of the 24 patients with pouch adenomas, 13 had all detected adenomas removed. Among the 13 patients who underwent complete adenoma removal, four (38.5%) developed recurrence. Among 11 (45.8%) patients with numerous polyps within the pouch, seven (63.6%) exhibited progression of pouch adenoma. The cumulative risks of pouch adenoma development at 5, 10, and 15 years after pouch surgery were 15.2%, 29.6%, and 44.1%, respectively. Severe colorectal polyposis (with more than 1000 polyps) was a significant risk factor for pouch adenoma development (hazard ratio, 2.49; 95% confidence interval: 1.04-5.96; P = 0.041). CONCLUSION: Pouch adenomas occur at a fairly high rate in association with FAP after restorative proctocolectomy, and a high colorectal polyp count is associated with pouch adenoma development.

The Prognostic Reliability of Lymphovascular Invasion for Patients with T3N0 Colorectal Cancer in Adjuvant Chemotherapy Decision Making.

Lymphovascular invasion (LVI) is a high-risk feature guiding decision making for adjuvant chemotherapy. We evaluated the prognostic importance and reliability of LVI as an adjuvant chemotherapy indicator in 1634 patients with pT3N0 colorectal cancer treated with curative radical resection between 2012 and 2016. LVI and perineural invasion (PNI) were identified in 382 (23.5%) and 269 (16.5%) patients, respectively. In total, 772 patients received adjuvant chemotherapy. The five-year recurrence-free survival (RFS) and OS rates were 92% and 94.8%, respectively. Preoperative obstruction, PNI, and positive margins were significantly associated with RFS and OS; however, adjuvant chemotherapy and LVI were not. Pathologic slide central reviews of 242 patients using dual D2-40 and CD31 immunohistochemical staining was performed. In the review cohort, the diagnosis of LVI and PNI was changed in 82 (33.9%) and 61 (25.2%) patients, respectively. Reviewed LVI, encompassing small vessel invasion, lymphatic invasion, and large vessel invasion, was not an independent risk factor associated with OS but was related to RFS. The prognostic importance of LVI and adjuvant chemotherapy was not defined because LVI may be underrecognized in pathologic diagnoses using hematoxylin and eosin staining slides only, leading to low recurrence rate predictions. Using LVI as a guiding factor for adjuvant chemotherapy requires further consideration.

Comparative survival risks in patients undergoing abdominoperineal resection and sphincter-saving operation for rectal cancer: a 10-year cohort analysis using propensity score matching.

PURPOSE: Abdominoperineal resection (APR) has been considered to have a higher risk of local recurrence and poorer survival outcome than sphincter-saving operation (SSO) in patients with rectal cancer. This study compared long-term oncologic outcomes and prognostic parameters in propensity score-matched patients who underwent APR and SSO. METHODS: This study analyzed 958 consecutive patients with lower rectal cancer who underwent preoperative chemoradiotherapy followed by APR or SSO between 2005 and 2015. Propensity score matching analysis was performed to adjust baseline characteristics, including clinical stage, tumor distance from the anal verge, and tumor size. RESULTS: In the entire cohort, the APR group had larger and lower tumors and showed significantly shorter 5-year disease-free survival (DFS) than the SSO group (64.5% vs. 75.8%, p = 0.01). After propensity score matching, there were no significant between-group differences in local (9.5% vs. 8.0%, p = 0.59) and systemic (27.9% vs. 23.4%, p = 0.3) recurrence rates, and 5-year DFS (67.5% vs. 69.9%, p = 0.49) and overall survival (80.8% vs. 82.9%, p = 0.65) rates. A lower number of lymph nodes retrieved was independently associated with recurrence and survival outcomes in the APR group, whereas poorly differentiated histology was an independent associated parameter in the SSO group. Advanced stage and perineural invasion were identified as independent prognostic parameters in both groups. CONCLUSIONS: This study indicated that the long-term oncologic outcomes of APR were comparable to those of SSO. Because prognostic parameters associated with oncologic outcomes differed between the respective procedures, correctable parameters could be ameliorated through complete total mesorectal excision and personalized systemic treatment.