Colon Cancer-specific Mortality Research Articles

Development and validation of a risk predictive nomogram for colon cancer-specific mortality: a competing risk model based on the SEER database

BackgroundUtilizing the SEER database, we developed a competing risk model along with a nomogram designed for the early identification of colon cancer-specific mortality (CSM) risk.MethodsClinical and pathological information, along with other significant data, were obtained from the SEER database. Patients were randomly divided into a training set and a validation set. We investigated the independent factors affecting CSM among colon cancer patients using univariate and multivariate analyses within a competing risk framework, ultimately developing a predictive tool for CSM in colon cancer.ResultsInvolving 40,261 individuals diagnosed with colon cancer, our study included 10,397 deaths directly due to the disease and an additional 5,828 from other causes. We used a competing risk model to predict cancer-specific mortality (CSM) in these patients. For the training dataset, the model’s area under the curve (AUC) for predicting 1-, 3-, and 5-year cancer-specific survival (CSS) was 0.835 (95% confidence interval [CI] 0.826 to 0.844), 0.849 (95% CI 0.843 to 0.855), and 0.843 (95% CI 0.836 to 0.850), respectively. In the validation group, the AUC values for the same time periods were 0.846 (95% CI 0.833 to 0.860), 0.853 (95% CI 0.843 to 0.862), and 0.846 (95% CI 0.835 to 0.856), respectively. In comparison, traditional survival analysis yielded higher cumulative CSM rates over time than those provided by our competing risk approach.ConclusionWe created a competitive risk assessment model along with a predictive tool designed to estimate CSM in patients with colon cancer. This nomogram demonstrates high accuracy and reliability, aiding medical professionals in making clinical decisions and developing patient follow-up plans.

Long-term Outcomes of Robot-assisted Versus Laparoscopic Surgery for Colon Cancer: A Nationwide Register-based Cohort Study.

To determine long-term survival in patients undergoing robot-assisted surgery (RAS) or laparoscopic surgery (LAS) for colon cancer. The potential long-term benefits of RAS compared with LAS for colon cancer are not well examined. Using a register-based approach, we aimed to compare these 2 surgical platforms in an analysis of long-term outcomes, including recurrence-free survival and all-cause- and colon cancer-specific mortality. A nationwide register-based cohort study of patients with Union for International Cancer Control stage I-III colon cancer undergoing planned RAS or LAS from 2010 through 2018. Patient demographic, clinical, and pathological data were retrieved from Danish national registers. Survival and recurrence rates were estimated by Cox proportional hazard multivariate regression analysis adjusting for baseline covariates. A total of 7565 patients [LAS=6905 (91%) and RAS=660 (9%)] were included in the complete case survival analysis. Patients undergoing LAS had a significantly increased risk of cancer recurrence [LAS=1178 (17.1%), RAS=82 (12.4%), P =0.002] with a mean follow-up time of 4.93 years (standard deviation 2.47). The survival analysis of recurrence-free survival favored RAS [hazard ratio adjusted =0.80, 95% CI (0.64-1.00), P =0.049]. No associations between the 2 surgical platforms were evident regarding all-cause [hazard ratio adjusted =0.98, 95% CI (0.82-1.17), P =0.783] or colon cancer-specific mortality [hazard ratio adjusted =0.89, 95% CI (0.67-1.18), P =0.405]. Adopting RAS for colon cancer was associated with improved recurrence-free survival. However, it did not cause a lower all-cause- or colon cancer-specific mortality.

Treatments and clinical outcomes in stage II colon cancer (CC) patients (pts) with 12-gene Oncotype DX Colon Recurrence Score assay-guided therapy: Real-world data.

3620 Background: The role of adjuvant chemotherapy (CT) in stage II CC is debated. The validated 12-gene Oncotype DX Colon Recurrence Score test provides a Recurrence Score (RS) result (range, 0-100) which estimates recurrence risk (RR) in stage II/III pts. We studied treatment and clinical outcomes in CC pts in whom treatment decisions incorporated the RS result. Methods: This prospectively designed cohort study included all stage II, MMR-P, CC pts who underwent the 12-gene Oncotype DX testing through Clalit between 1/2011 and 12/2016 and had available data with minimum 3-yr follow-up. Kaplan-Meier (KM) estimates and log-rank tests were used to compare RR and CC specific mortality (CCSM) between RS categories. Multivariable analysis (MVA) identified variables associated with RR/CCSM. Results: The analysis included 938 pts. Median age, 68 (IQR, 60-76) yrs; 96% had T3 tumors, and 89% had ≥12 nodes examined. Median RS was 26 (IQR, 19-33). The 3 RS categories (0-29, 30-40, and 41-100) included 65%, 24%, and 11% of pts, respectively. The overall CT use rate was 24%, with a significant difference between the 3 categories (14%, 36%, and 60%, respectively, P< .0001). Pts with very low RS (0-15) comprised 14% of the cohort (CT use rate, 11%). Younger pts, and those with invasion/perforation/obstruction were more likely to receive CT. Clinical outcomes with a median follow up of 6.9 (IQR, 5.5-8.6) yrs are presented (Table). Among untreated pts, KM estimates for RR and CCSM differed significantly between the 3 RS categories ( P< .0001). Outcome of untreated RS 0-15 pts was excellent. In an MVA model, male sex, presence of invasion/perforation/obstruction and higher RS category (RS 41-100 vs 0-29 and vs 30-40, but not RS 30-40 vs 0-29) were associated with increased RR. For CCSM, the results were similar, but this time age ≥70 yrs replaced sex as a significant prognostic variable. Clinical outcomes within each RS group did not differ significantly between treated and untreated pts, but were numerically better with CT in the RS 41-100 group. Conclusions: This real-world analysis showed that the RS results provide independent prognostic information in stage II CC. Further studies are needed to investigate the potential role of the RS result as a predictor of CT benefit, but the data suggest that this benefit may be limited to pts with high RS results. [Table: see text]

Growth hormone and gastrointestinal malignancy: An intriguing link.

Growth hormone (GH) excess is associated with several systemic complications, one of which is the increased risk of neoplastic processes particularly of the gastrointestinal (GI) tract. Among the GI neoplasms, the most reported association is with benign and malignant neoplasms of the colon. In the majority of published literature, an increased incidence of GI neoplasms, both colonic adenomas as well as colorectal carcinoma is reported. However, the studies on colon cancer-specific mortality rate are conflicting with recent studies reporting similar cancer-specific mortality rates in comparison to controls. Many studies have reported an association of colorectal neoplasms with GH levels. Pathogenic mechanisms put forward to explain this association of GH excess and GI neoplasms primarily involve the increased GH-insulin-like growth factor 1 (IGF-1) signaling. Both GH and IGF-1 have proliferative, anti-apoptotic, and angiogenic effects on the systemic tissues leading to cellular proliferation. Other contributing factors to the increased risk of GI neoplasms include slow intestinal transit with a redundant large bowel, altered bile acids, deranged local immune response, shared genetic susceptibility factors and hyperinsulinemia. In view of the increased risk association, most guidelines for the care of acromegaly patients recommend an initial screening colonoscopy. Recommendations for further follow-up colonoscopy differ but broadly, the guidelines agree that it depends on the findings at first colonoscopy and state of remission of GH excess. Regarding the concern about the risk of colorectal cancers in patients receiving recombinant GH therapy, most cohort studies do not show an increased risk.

The impact of hospital volume on survival in patients with locally advanced colonic cancer.

High hospital volume has been shown associated with improved survival in patients with several cancers. The aim of this nationwide cohort study was to investigate whether hospital volume affects survival in patients with locally advanced colonic cancer. All patients with non-metastatic locally advanced colonic cancer diagnosed between 2007 and 2017 in Sweden were included. Tertiles of annual hospital volume of locally advanced colonic cancer were analysed and 5-year overall and colonic cancer-specific survival were calculated with the Kaplan-Meier method. HRs comparing all-cause and colonic cancer-specific mortality rates were estimated using Cox models adjusted for potential confounders (age, sex, year of diagnosis, co-morbidity, elective/emergency resection, and university hospital) and mediators (preoperative multidisciplinary team assessment, neoadjuvant chemotherapy, radical resection, and surgical experience). A total of 5241 patients were included with a mean follow-up of 2.7-2.8 years for low- and high-volume hospitals. The number of patients older than 79 years were 569 (32.3 per cent), 495 (29.9 per cent), and 482 (26.4 per cent) for low-, medium- and high-volume hospitals respectively. The 3-year overall survival was 68 per cent, 60 per cent and 58 per cent for high-, medium- and low-volume hospitals, respectively (P < 0.001 from log rank test). High volume hospitals were associated with reduced all-cause and colon cancer-specific mortality after adjustments for potential confounders (HR 0.76, 95 per cent CI 0.62 to 0.93 and HR 0.73, 95 per cent CI 0.59 to 0.91, respectively). The effect remained after inclusion of potential mediators. High hospital volume is associated with reduced mortality in patients with locally advanced colonic cancer.

The Prognostic Value of Adjuvant Chemotherapy in Colon Cancer With Solitary Tumor Deposit.

PurposeThe aim of this study is to investigate the survival benefit of adjuvant chemotherapy in patients with colon cancer with the solitary tumor deposit (TD).MethodsThe primary study outcomes used in this study were colon cancer–specific survival (CSS) and overall survival (OS). The differences of the distribution of categorical variables in patients with colon cancer with the solitary TD according to adjuvant chemotherapy administration were tested using the Pearson’s chi-square test. The Kaplan–Meier method was utilized to evaluate CSS and OS. Hazard ratio (HR) and 95% confidence interval (CI) were calculated on the basis of Cox regression models to assess the prognostic value of different demographic and clinicopathological characteristics.ResultsA total of 877 patients with TanyN1cM0 colon cancer with solitary TD were identified in our analysis. It was found that OS (75.4% vs. 42.8% for 5-year OS rate, p < 0.001) and CSS (82.9% vs. 69.3% for 5-year CSS rate, p < 0.001) of patients with colon cancer with adjuvant chemotherapy administration were significantly better than those without adjuvant chemotherapy administration. Multivariate Cox survival analyses revealed that the overall and colon cancer–specific mortality risks of patients with adjuvant chemotherapy administration were decreased by 64.4% (HR = 0.356, 95% CI = 0.265–0.479, p < 0.001) and 57.4% (HR = 0.426, 95% CI = 0.286–0.634, p < 0.001) compared with those without adjuvant chemotherapy administration, respectively.ConclusionsAdjuvant chemotherapy administration could significantly improve OS and CSS in patients with colon cancer with the solitary TD. This is the first study to investigate and demonstrate the survival benefit of adjuvant chemotherapy in patients with colon cancer with the solitary TD.

Association Between Chemotherapy and Survival in T1 Colon Cancer With Lymph Node Metastasis: A Propensity-Score Matched Analysis

This study aimed to comprehensively examine the efficacy of chemotherapy in T1 colon cancer patients with lymph node metastasis.MethodsThe differences in categorical variables in colon cancer patients according to lymph node status were evaluated by Pearson’s chi-square test. The Kaplan-Meier method was used to assess Cancer-specific survival (CSS) and overall survival (OS) with the log-rank test. Cox proportional hazards models were built, multivariate Cox regression analyses were performed with the hazard ratio (HR) and 95% confidence interval (CI) to identify the potential independent prognostic factors. Propensity score matching was also undertaken to adjust for treatment bias due to measured confounders.ResultsYounger age (52.2% VS. 43.0% for ≤ 65 years old, p < 0.001), female gender (50.3% VS. 46.8% for female, p < 0.001), more lymph nodes harvested (68.1% VS. 46.6% for ≥12 lymph nodes harvested, p < 0.001), Black race (13.6% VS. 12.0% for the Black race, p < 0.001), and higher tumor grade (14.2% VS. 5.6% for grade III/IV, p < 0.001) were more prone to be diagnosed with lymph node involvement. The receipt of adjuvant chemotherapy following radical surgery significantly reduced the risk of colon cancer-specific mortality by 33.9% after propensity-score matching (HR = 0.661, 95%CI = 0.476-0.917, p = 0.013).ConclusionsYounger age, female gender, more lymph nodes harvested, Black race, and higher tumor grade were more prone to be diagnosed with lymph node involvement. The receipt of adjuvant chemotherapy following radical surgery also significantly decreased the risk of colon cancer-specific mortality by 33.9% in T1 colon cancer with lymph node involvement.

Detailed incidence and mortality trends of early-onset colorectal cancer in Canada.

e15539 Background: There has been a consistent increase in the incidence of early-onset colorectal cancer (eoCRC), under the age of 50, in Canada since the late 1990s. Questions remain surrounding how these trends vary by topography, histology, and stage, and related trends with CRC-specific mortality. Methods: CRC incidence data were obtained from the Canadian Cancer Registry and CRC-specific mortality data from the Canadian Vital Statistics – Death Database for the years 2000 to 2017. Age-specific average annual percent changes (AAPC) in the incidence (by topography and histology) and mortality rates of CRC were estimated using the National Cancer Institute’s Joinpoint Regression Program. To determine age-specific differences (5-year age groups) in CRC diagnosis at late stage (III and IV) for years 2011 to 2017 combined, a logistic regression model adjusting for sex with the 50-54 age group as the referent was conducted. Results: AAPCs and 95% confidence intervals in the rates of incidence (topography and histology) and mortality of eoCRC from 2000 to 2017 in Canada are presented in Table. Different trends in topography were observed across sexes with the largest increases in the distal colon (splenic flexure, descending, and sigmoid) and rectum among males and rectum only among females. Significant increases were observed for non-mucinous adenocarcinomas, while significant decreases were observed for mucinous adenocarcinomas among the 40-49 age group. Compared to the 50-54 age group, only the 45-49 group had a significantly higher odds of developing late-stage colon cancer, while men and adults 25-49 had a higher odds of developing late stage rectal cancer. Despite increases in the incidence of eoCRC there has only been a significant increase in mortality for men aged 20-39. Trends in mortality vary by site, with significant decreases observed for colon cancer-specific mortality among the 40-49 age group and increases in rectal cancer-specific mortality for adults aged 20-49. Conclusions: These results indicate that the largest increases in incidence and mortality for eoCRC have occurred in the rectum and trends have varied by sex. Further research on the etiology and treatment outcomes of eoCRC patients are warranted for this patient population.[Table: see text]

Real-world survival outcomes associated with completion of adjuvant chemotherapy for stage III colon cancer.

3596 Background: The optimal duration of adjuvant combination chemotherapy administered to patients with stage III colon cancer is debated. Our study assessed the effect of completed chemotherapy cycles on 3-year colon cancer-specific mortality, as well as the effect of dose reduction and early discontinuation of oxaliplatin in patients with 100% completion, within a real-world population. Methods: 4,147 patients undergoing major resection between 01 June 2014 and 30 April 2017 with pathological stage III colon cancer in the English National Health Service were identified. Chemotherapy data were obtained from linked administrative hospital records and a national chemotherapy dataset. Patients were stratified according to completion of &lt; 50% ( &lt; 6 FOLFOX cycles or &lt; 4 CAPOX cycles), 50-92% (6-11 FOLFOX cycles or 4-7 CAPOX cycles) or 100% of cycles (12 FOLFOX cycles or 8 CAPOX cycles). Competing-risk regression analysis for 3-year colon cancer-specific death was performed with adjustment for patient, tumour and hospital-level characteristics to estimate subdistribution hazard ratios (sHR) as a measure of relative risk. Results: Patients included within our study were less fit and had increased rates of high-risk disease (T4 and/or N2 pathological staging) compared to the IDEA study. For FOLFOX, the 3-year cumulative incidence of colon cancer-specific death in patients completing 100% of cycles was 15.1% (95% CI, 12.8% to 17.6%), 18.2% (95% CI, 15.3% to 21.3%) for 50-92% of cycles and 26.4% (95% CI, 20.6% to 32.5%) for &lt; 50% of cycles. For CAPOX, this was 12.0% (95% CI, 10.2% to 14.0%) for 100% completion of cycles, 18.2% (95% CI, 15.6% to 21.0%) for 50-92% of cycles, and 19.8% (95% CI, 15.8% to 24.1%) for &lt; 50% cycles. Compared to 100% completion of FOLFOX cycles, colon cancer-specific death was higher in patients recorded as completing &lt; 50% (sHR 2.17; 95% CI, 1.56 to 3.03; P = &lt; 0.001) and 50-92% of FOLFOX cycles (sHR 1.40; 95% CI, 1.09 to 1.78; P = 0.007). Compared to 100% completion of CAPOX cycles, colon cancer-specific death was higher in patients recorded as completing &lt; 50% (sHR 2.02; 95% CI 1.53 to 2.67; P&lt; 0.001) and 50-92% of CAPOX cycles (sHR 1.63; 95% CI 1.27 to 2.10; P&lt; 0.001). Dose reduction and early discontinuation of oxaliplatin did not have a statistically significant effect on mortality. Conclusions: Patients within the real world setting were more likely to have poor prognostic factors. Those who completed adjuvant chemotherapy for stage III colon cancer had improved survival rates regardless of dose reduction or early discontinuation of oxaliplatin.

Preoperative multidisciplinary team assessment is associated with improved survival in patients with locally advanced colon cancer; a nationwide cohort study in 3157 patients

IntroductionMultidisciplinary team (MDT) assessment is associated with improved survival in locally advanced rectal cancer, but the effect of an MDT assessment on survival in locally advanced colon cancer has not been reported. The aim of this national population-based cohort study was to establish if preoperative MDT assessment affects prognosis in patients with primary locally advanced colon cancer. Material and methodsAll patients in Sweden with locally advanced colon cancer, without metastatic disease, who underwent an elective colon resection between 2010 and 2017 were identified through the Swedish Colorectal Cancer Registry (SCRCR), and the cohort was linked to national registers. Data on patient characteristics, preoperative staging, surgical procedures, recurrence and survival were collected from SCRCR. The association between MDT assessment and colon cancer-specific survival was evaluated using Kaplan-Meier survival curves and Cox proportional hazards models. The multivariable analysis was adjusted for sex, age, ASA grade, CCI, time period, pN, region and preoperative MDT. ResultsMDT assessment was performed in 2663 patients (84.4%) of 3157 eligible patients. The 3-year colon cancer-specific survival was higher following MDT, compared with no MDT assessment (80% versus 68%). MDT assessment was independently associated with reduced colon cancer-specific mortality (HR 0.70, 0.57–0.84 95% CI). ConclusionPreoperative MDT assessment is associated with an improved long-term survival in patients with locally advanced colon cancer and should be mandatory in patients with suspected locally advanced colon cancer.

Re-Evaluation of the Survival Paradox Between Stage IIB/IIC and Stage IIIA Colon Cancer.

ObjectiveWe conducted this large population-based study to re-evaluate the survival paradox between stage IIB/C and stage IIIA colon cancer based on the newest staging criteria.MethodsColon cancer patients were recruited from the Surveillance, Epidemiology, and End Results (SEER) database using SEER*Stat software (version 8.3.4) with strict inclusion criteria. We used Chi-square test to compare categorical variables between patients diagnosed with stage IIB/IIC and stage IIIA colon cancer. Survival probabilities were then assessed using the Kaplan–Meier method. Cox proportional hazards models were used to analyze hazard ratios (HRs) and 95% confidence intervals (CIs) of clinicopathologic characteristics in stage IIB/IIC and stage IIIA colon cancer patients.ResultsIn the current study, a total of 9,227 eligible colon cancer patients were collected from the SEER database between 2010 and 2015. It was found that stage IIIA had 66.4% decreased risk of colon cancer-specific mortality compared with stage IIB (HR = 0.336, 95%CI = 0.286–0.394 for stage IIIA, P < 0.001, using stage IIB as the reference) after the adjustment for other known prognostic factors. And T1N2a colon cancer had significantly lower 5-year overall survival (OS) rate compared with T2N1 disease (74.7% vs. 57.1%, P = 0.018).ConclusionsOur study confirmed the existence of survival paradox between stage IIB/IIC and stage IIIA colon cancer based on the newest staging criteria. What is more, the subgroup analyses revealed that T1N2a had the least influence on the survival paradox. N2a colon cancer seemed to be associated with worse prognosis than T2 disease, which would give us a better understanding of tumor biology of colon cancer and be conducive to the refinement of individualized treatment regimens in stage III disease.

Is Radical Surgery Alone Enough in T1-3N1a Colon Cancer?

Background: Low lymphatic tumor burden is associated with a better prognosis. However, it is uncertain whether those patients diagnosed as cN0 found to be pN+ could be a favorable subgroup in stage III disease. Radical surgery alone might avoid overtreatment in those patients.Methods: Eligible patients diagnosed with colon cancer without metastasis were recruited from the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2016 using SEER*Stat 8.3.5 software (Surveillance Research Program, National Cancer Institute) and divided into two groups: surgery group (n = 3,081) and surgery followed by adjuvant chemotherapy group (n = 4,591). Overall survival (OS) and cause-specific survival (CSS) differences were assessed by Kaplan–Meier analysis, and survival differences were estimated with log-rank tests. Univariate and multivariate Cox proportional hazard regressions were used to assess hazard ratios (HRs) and 95% confidence intervals (CIs) for colon cancer patients.Results: A total of 7,672 pT1-3N1a colon cancer patients were recruited from 208,751 colon cancer patients. The 5-year CSS rates of patients without and with adjuvant chemotherapy were 80.0 and 90.7%, respectively. The receipt of adjuvant chemotherapy after the radical resection of the primary tumor was independently associated with 57.3% decreased risk of colon cancer-specific mortality compared with surgery alone (HR = 0.427, 95% CI = 0.370–0.492, P < 0.001, using surgery alone as the reference).Conclusions: Adjuvant chemotherapy was significantly associated with improved prognosis and radical surgery alone did not provide enough treatment for colon cancer with very low lymphatic tumor burden.

Early Elective Surgery After Colon Cancer Diagnosis has Higher Risk of Readmission and Death.

We hypothesized colon resection within 30 days of diagnosis of cancer would have higher rates of readmission and cancer specific mortality, unless there was demonstrated evidence of preoperative workup. Few studies have examined if negative consequences exist with expedited elective surgery after diagnosis of colon cancer. Surgery in a shorter time frame may result in a lack of appropriate preoperative care. Retrospective analysis of 25,407 patients in the Surveillance Epidemiology and End Results registry who underwent elective surgical resection for colon cancer from 2010 to 2015. Cohort stratified by age (66-75 vs >75 years). Primary outcomes of interest were 30-day readmission and 5-year colon cancer specific mortality. Relationships between timing of surgery and outcomes were assessed. On unadjusted analysis, surgery before 20 days of diagnosis was associated with higher risk of 30-day readmission and colon cancer specific mortality in both age groups. Among those age 66 to 75 years old, adjusting for patient factors and preoperative workup eliminated the risk of 30-day readmission (risk ratio 1.5-0.9 for 0-10 days, risk ratio 1.3-0.9 for 11-20 days). However, the risk for colon cancer specific mortality, although reduced, persisted (hazard ratio 2.2-1.3 for 0-10 days, hazard ratio 2.0-1.2 for 11-20 days). In the cohort older than 75 years, adjusting for patient level factors and preoperative workup eliminated risk of surgery 20 days postop or sooner. The risk associated with short time to surgery (within 30 days) may be mitigated if full oncologic workups are provided.

Association of age and cause-special mortality in patients with stage I/ II colon cancer: A population-based competing risk analysis.

PurposeThis study aimed to determine the probability and prognostic factors of colon cancer-specific mortality (CCSM) and noncancer-specific mortality (NCSM) for patients with stage I/II colon cancer and evaluate the association of age on cause-specific mortality.Materials and methodsFrom Surveillance, Epidemiology, and End Results (SEER) database, we identified 33152 patients with stage I/II colon cancer undergoing surgery between 2004 and 2011. The cumulative incidence of CCSM and NCSM was calculated, and competing risk analysis was performed to investigate prognostic factors for cause-specific mortality.ResultsIn patients <50, 50–75, and >75 years of age, 5-year cumulative incidence of CCSM was 5.7%, 7.8%, and 16.1%, respectively (overall, 10.6%); 5-year cumulative incidence of NCSM was 2.2%, 7.1%, and 26.9%, respectively (overall, 13.8%). The probability of CCSM and NCSM increased with advanced age. The 5-year cumulative incidence of CCSM was higher than NCSM in patients <50 years of age, whereas lower in patients >75 years of age. The probability of CCSM and NCSM was similar in patients 50–75 years of age. Competing-risk multivariable analysis demonstrated that increasing age was a strong predictor of CCSM (per year increase, SHR 1.03,95% confidence interval [CI]: 1.03–1.04). Age was most predictive of NCSM: (per year increase, SHR 1.08, 95% CI: 1.08–1.08).ConclusionAge was significantly associated with an increased cumulative incidence of CCSM and NCSM of patients with stage I/II colon cancer underwent surgery. NCSM was a significant competing event and should be adequately considered when performing survival analysis.

Prognostic implications of mucinous histology in stage III colon cancer with the receipt of adjuvant chemotherapy.

There is still a debate about the survival benefit of chemotherapy in stage III mucinous colon cancer, we then conduct a comprehensive assessment of the efficacy of adjuvant chemotherapy in this population. The data used in the current study were extracted from the Surveillance, Epidemiology and End Results (SEER) database. Chi-squared (χ2) test was used to compared patient characteristics according to the histology. The outcome of the survival analysis used in the current study was cancer-specific survival (CSS). Univariable and multivariable analyses were carried out using the Cox proportional hazards regression models to evaluate the prognostic characteristics associated with CSS of colon cancer. And the risks of mortality were presented as hazard ratios (HRs) with 95% confidence intervals (CIs). A total of 68,976 patients diagnosed with stage III colon cancer were included in our analyses, including mucinous adenocarcinoma (MAC, N=6,592) and non-mucinous adenocarcinoma (NMA, N=62,384). In NMA, the receipt of chemotherapy had 46.0% independently decreased risk of colon cancer-specific mortality compared to non-chemotherapy group (HR =0.540, 95% CI: 0.523-0.558, P<0.001). In MAC, the receipt of chemotherapy had 37.7% independently decreased risk of colon cancer-specific mortality compared to non-chemotherapy group (HR =0.623, 95% CI: 0.566-0.685, P<0.001). MAC was associated with worse prognosis and was less responsive to chemotherapy compared with NMA in stage III colon cancer. However, stage III mucinous colon cancer still need to be treated with chemotherapy because of the significant survival benefit and specialized treatment plans for MAC were quite necessary in the future.

Surveillance Colonoscopy in Older Stage I Colon Cancer Patients and the Association With Colon Cancer-Specific Mortality.

Guideline-issuing groups differ regarding the recommendation that patients with stage I colon cancer receive surveillance colonoscopy after cancer-directed surgery. This observational comparative effectiveness study was conducted to evaluate the association between surveillance colonoscopy and colon cancer-specific mortality in early stage patients. This was a retrospective cohort study of the Surveillance, Epidemiology, and End Results database combined with Medicare claims. Surveillance colonoscopy was assessed as a time-varying exposure up to 5 years after cancer-directed surgery with the following groups: no colonoscopy, one colonoscopy, and ≥ 2 colonoscopies. Inverse probability of treatment weighting was used to balance covariates. The time-dependent Cox regression model was used to obtain inverse probability of treatment weighting-adjusted hazard ratios (HRs), with 95% confidence intervals (CIs) for 5- and 10-year colon cancer, other cancer, and noncancer causes of death. There were 8,783 colon cancer cases available for analysis. Overall, compared with patients who received one colonoscopy, the no colonoscopy group experienced an increased rate of 10-year colon cancer-specific mortality (HR = 1.63; 95% CI 1.31-2.04) and noncancer death (HR = 1.36; 95% CI 1.25-1.49). Receipt of ≥ 2 colonoscopies was associated with a decreased rate of 10-year colon cancer-specific death (HR = 0.60; 95% CI 0.45-0.79), other cancer death (HR = 0.68; 95% CI 0.53-0.88), and noncancer death (HR = 0.69; 95% CI 0.62-0.76). Five-year cause-specific HRs were similar to 10-year estimates. These results support efforts to ensure that stage I patients undergo surveillance colonoscopy after cancer-directed surgery to facilitate early detection of new and recurrent neoplastic lesions.

Preoperative serum carcinoembryonic antigen elevation in stage I colon cancer: improved risk of mortality in stage T1 than in stage T2.

This study aimed to investigate the implications of preoperative serum carcinoembryonic antigen (CEA) elevation in cause-specific survival (CSS) of patients diagnosed with stage I (T1N0M0 and T2N0M0) colon cancer. Eligible patients diagnosed with stage I colon cancer from the Surveillance, Epidemiology, and End Results (SEER) database from January 2004 to December 2010 were included in this respective and propensity score-matched (PSM) study. Some Cox proportional hazards models were constructed to identify prognostic factors associated with oncologic outcomes of colon cancer. Pearson's chi-squared tests and Kaplan-Meier methods were performed. The median follow-up time of the whole cohort was 79months. A total of 16,659 patients diagnosed with stage I colon cancer were identified from the SEER database. Multivariate Cox analyses showed that stage T1N0M0 in the context of serum CEA elevation (T1, CEA+) presented up to 158.4% increased risk of colon cancer-specific mortality compared with stage T1N0M0 in the context of normal serum CEA [hazard ratio (HR) = 2.584, 95% confidence interval (CI) = 2.167-3.082, P < 0.001]. After PSM, Kaplan-Meier survival curves of stage T1N0M0 colon cancer showed that 5-year CSS rates of normal and elevated CEA were 94.8% and 96.6% (P < 0.001). This large population-based and propensity score-matched study with long follow-up time provides the first evidence that stage T1N0M0 colon cancer with the elevation of preoperative serum CEA would be a surrogate of aggressive tumor biology and predict poor prognosis. In addition, this subgroup of colon cancer might need to be paid more attention of clinicians.

Timing of first surveillance colonoscopy in stage I colon cancer patients and the association with colon cancer-specific survival.

618 Background: Surveillance colonoscopy following curative surgery in stage I colon cancer patients is controversial. This study was conducted to assess the relationship between timing of first surveillance colonoscopy and 5-year colon cancer-specific survival. Methods: This was a retrospective cohort study of the Surveillance, Epidemiology, and End Results database combined with Medicare claims. Stage I colon cancer patients (66-84 years of age) were categorized according to receipt of first colonoscopy following cancer-directed surgery as: Year 1, Year 2, Year 3, and No Colonoscopy within 3 years of surgery. Propensity score weighting was used to balance covariates. Cox regression was used to obtain hazard ratios for the relative risk of 5-year colon cancer-specific death, adjusted survival estimates, and the number needed to treat (NNT) with colonoscopy in Year 1 to prevent a colon cancer-specific death in the other groups. Results: There were 8,494 stage I colon cancer patients available for analysis. Regarding 5-year colon cancer-specific mortality, compared to Year 1 patients, the No Colonoscopy group experienced 2.2 times the risk of colon cancer-specific death (HR, 2.23; 95% CI, 1.38 to 3.61). Those who received ≥ 1 additional colonoscopies in the two years following their initial assessment experienced a significant 73% decreased risk of death (HR, 0.27; 95% CI, 0.16 to 0.45). Delaying colonoscopy (Years 2 &amp; 3) did not result in a statistically significant increased risk of death. Although the absolute difference in 5-year adjusted survival was small, if all patients in the No Colonoscopy group received a colonoscopy in Year 1, 46.2% (n = 49.9) of the 108 colon cancer deaths that occurred in this group could have been prevented. Conclusions: Although stage I colon cancer patients have a good prognosis, patients who received colonoscopy within one year of cancer-directed surgery experienced significantly better survival than patients who did not receive colonoscopy within 3 years of surgery. The results of this study justify efforts to ensure that stage I colon cancer patients receive colonoscopic surveillance testing approximately 1 year following cancer-directed surgery.

Association of diabetes with colorectal cancer treatment and outcomes.

e18112 Background: Diabetes mellitus (DM) is associated with an increased incidence of colorectal cancer, but the impact of diabetes on colorectal cancer (CRC) prognosis and treatment patterns remains unknown. As outcomes in both CRC and DM have improved, appropriate co-management of the two diseases has become a priority to help patients live longer and healthier. Methods: A systematic search of PubMed, Embase, and CINAHL databases was performed to evaluate/assess the association of diabetes with colon cancer treatment patterns and outcomes, including recurrence rates (RR), disease free survival (DFS), colon cancer-specific (CSM) and all-cause mortality (ACM). We included English language peer-reviewed studies through November 2016 following the preferred reporting items of systematic reviews and meta-analyses (PRISMA) method. We applied STROBE quality criteria and conducted a random-effects meta-analysis. An inconsistency index (I2) was used to estimate the heterogeneity between studies. Results: After reviewing 2,611 reports, 35 studies were included that described an association of DM with CRC treatment patterns or outcomes. A meta-analysis of 14 studies that assessed (ACM) among 146,129 patients demonstrated an increased risk for ACM for CRC patients with DM (OR 1.28, 95% CI 1.16-1.42, I2 = 80%, P &lt; .00001). No statistical significance was found in comparing 4 studies that looked at CSM (OR 0.91, 95% CI .72-1.14, I2 = 89%, P = 0.42). Analysis of 4 studies that assessed DFS found lower DFS in patients with DM (OR 1.75, 95% CI 1.33-2.31, I = 3%, P &lt; .0001). Aggregating 3 studies that evaluated RFS demonstrated no clear association of DM and RFS(OR 1.12, CI 95% 0.91-1.38, I = 64%, P = .27). No consistent treatment discrepancies were noted in 6 studies that assessed the impact of DM on various CRC treatment modalities (receipt of surgery, chemotherapy, radiation). Conclusions: CRC patients with diabetes are at a greater risk for ACM and have worse DFS compared to those without DM. Analysis was limited due to study heterogeneity. We did not find consistent evidence that CRC is treated differently in patients with DM. Further study is warranted to clarify the mechanism of poor outcomes in CRC patients with DM and to improve survival.

Marriage is a dependent risk factor for mortality of colon adenocarcinoma without a time-varying effect.

BackgroundIt has been well recognized that the effects of many prognostic factors could change during long-term follow-up. Although marriage has been proven to be a significant prognostic factor for the survival of colon cancer, whether the effect of marriage is constant with time remain unknown. This study analyzed the impact of marital status on the mortality of colon cancer patients with an extended Cox model that allowed for time-varying effects.MethodsWe identified 71,955 patients who underwent colectomy between 2004 and 2009 to treat colon adenocarcinoma from the Surveilance, Epidemiology and End Results Database. The multivariate extended Cox model was used to evaluate the effect of marital status on all-cause mortality, while the Fine-Gray competing risks model was used for colon cancer-specific mortality, with death from other causes as the competing risk.ResultsThe unmarried patients carried a 1.37-fold increased risk of all-cause mortality compared with the married patients (95%CI: 1.33-1.40; p<0.001), and the hazard ratio remained constant over time. Being unmarried was at a higher risk of death from colon adenocarcinoma as well as death from other causes. Four variables including tumor site, tumor grade, sex and TNM stage were proved to have time-varying effects on survival.ConclusionsMarriage is a dependent prognosis factor for survival of surgically treated colon adenocarcinoma patients. Psychological interventions are suggested to improve receipt of treatment among unmarried patients, as their poor survival may be due to the inefficient treatment.