Chemotherapy use in stage III colon cancer: a National Cancer Database analysis

Pathomics Signature for Prognosis and Chemotherapy Benefits in Stage III Colon Cancer

Importance

The current TNM staging system may not provide adequate information for prognostic purposes and to assess the potential benefits of chemotherapy for patients with stage III colon cancer.

Objective

To develop and validate a pathomics signature to estimate prognosis and benefit from chemotherapy using hematoxylin-eosin (H-E)-stained slides.

Design, Setting, and Participants

This retrospective prognostic study used data from consecutive patients with histologically confirmed stage III colon cancer at 2 medical centers between January 2012 and December 2015. A total of 114 pathomics features were extracted from digital H-E-stained images from Nanfang Hospital of Southern Medical University, Guangzhou, China, and a pathomics signature was constructed using a least absolute shrinkage and selection operator Cox regression model in the training cohort. The associations of the pathomics signature with disease-free survival (DFS) and overall survival (OS) were evaluated. Patients at the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China, formed the validation cohort. Data analysis was conducted from September 2022 to March 2023.

Main Outcomes and Measures

The prognostic accuracy of the pathomics signature as well as its association with chemotherapy response were evaluated.

Results

This study included 785 patients (mean [SD] age, 62.7 [11.1] years; 437 [55.7%] male). A pathomics signature was constructed based on 4 features. Multivariable analysis revealed that the pathomics signature was an independent factor associated with DFS (hazard ratio [HR], 2.46 [95% CI, 2.89-4.13]; P < .001) and OS (HR, 2.78 [95% CI, 2.34-3.31]; P < .001) in the training cohort. Incorporating the pathomics signature into pathomics nomograms resulted in better performance for the estimation of prognosis than the traditional model in a concordance index comparison in the training cohort (DFS: HR, 0.88 [95% CI, 0.86-0.89] vs HR, 0.73 [95% CI, 0.71-0.75]; P < .001; OS: HR, 0.85 [95% CI, 0.84-0.86] vs HR, 0.74 [95% CI, 0.72-0.76]; P < .001) and validation cohort (DFS: HR, 0.83 [95% CI, 0.82-0.85] vs HR, 0.70 [95% CI, 0.67-0.72]; P < .001; OS: HR, 0.80 [95% CI, 0.78-0.82] vs HR, 0.69 [0.67-0.72]; P < .001). Further analysis revealed that patients with a low pathomics signature were more likely to benefit from chemotherapy (eg, combined cohort: DFS: HR, 0.44 [95% CI, 0.28-0.69]; P = .001; OS: HR, 0.43 [95% CI, 0.29-0.64]; P < .001).

Conclusions and Relevance

These findings suggest that a pathomics signature could help identify patients most likely to benefit from chemotherapy in stage III colon cancer.

Race/Ethnicity and Social Determinants of Health and Their Impact on Receiving Appropriate Chemotherapy for Colon Cancer

INTRODUCTION

Despite the heightened understanding and improved treatment for colorectal cancer in the United States, social determinants of health (SDH) play a significant role in the colorectal cancer outcomes. We sought to investigate the relationship between SDH and appropriate utilization of adjuvant chemotherapy in stage III colon cancer.

METHODS

For this retrospective study, we utilized data from the National Cancer Data Base (NCDB). Descriptive statistics are reported, including means and 95% confidence intervals for continuous variables and frequency and proportions for categorical variables. Univariate hypothesis testing to identify categorical level factors associated with treatment used Wilcoxon rank sum or Kruskal-Wallis tests, with multivariate analyses performed using regression analysis.

RESULTS

Significant differences were as follows: Metro-non-Hispanic White patients received treatment less frequently (69.7%) when compared to Metro-non-Hispanic Black patients (73.4%) (P < .001). Increasing age was a negative predictor of likelihood to receive with those over 65 years old having an 83% decrease in likelihood to receive chemotherapy when compared to those under 65 (P < .001). Medicaid patients were 47% less likely and Medicare patients were 40% less likely to receive chemotherapy when compared to those with private insurance (P < .001). Rural patients were statistically more likely to receive chemotherapy (OR 1.42, 1.32-2.52, P < .001) as were urban patients, (OR 1.26, 1.20-1.31, P < .001) when compared to patients residing in metro areas.

CONCLUSION

Age, living in a Metro area, and government insurance status at diagnosis are negatively correlated with the likelihood of receiving chemotherapy. Race was not associated with differences in receiving chemotherapy.

Effects of tumour budding on adjuvant chemotherapy in colorectal cancer

BACKGROUND

High tumour budding has been indicated as a risk factor of poor survival in colorectal cancer. This study aimed to investigate the impact of tumour budding grades and the use of adjuvant chemotherapy on prognosis in patients with colorectal cancer.

METHODS

This study included consecutive colorectal cancer patients who underwent radical surgery for primary colorectal adenocarcinoma at The Sixth Hospital of Sun Yat-sen University between 2009 and 2019. Tumour budding was assessed based on the recommendations of the International Tumor Budding Consensus Conference using haematoxylin and eosin (H&E)-stained slides with tumour samples. The primary outcome of interest was to correlate tumour budding with disease-free survival and overall survival; the secondary outcome was investigation of the impact of adjuvant therapy on different tumour budding grades. In addition, a subgroup analysis was performed for the effects of lymphocytic infiltration on adjuvant chemotherapy in patients with Bd3.

RESULTS

Of 709 eligible patients, 412 with colorectal cancer were included. According to the International Tumor Budding Consensus Conference, 210 (50.9 per cent), 127 (30.8 per cent) and 75 (18.2 per cent) were classified as low budding (Bd1), intermediate budding (Bd2) and high budding (Bd3) respectively. Patients with Bd1, Bd2 and Bd3 had 5-year disease-free survival rates of 82.9 per cent, 70.1 per cent and 49.3 per cent respectively, and 5-year overall survival rates of 90 per cent, 79.5 per cent and 62.7 per cent respectively (P <0.001). Adjuvant chemotherapy yielded a significant survival benefit in patients with Bd3 (5-year disease-free survival, 65 per cent versus 31.4 per cent, P <0.001; 5-year overall survival, 84.4 per cent versus 63.1 per cent, P <0.001), but not in those with Bd1 or Bd2. In patients with Bd3, the benefit of adjuvant chemotherapy was maintained in those with low, but not high lymphocytic infiltration.

CONCLUSION

High grade of tumour budding was strongly correlated with poorer survival outcomes in colorectal cancer. Patients with Bd3 benefited from adjuvant chemotherapy, with the exclusion of patients with high lymphocytic infiltration.

Variations in the Type of Adjuvant Chemotherapy Among Stage III Colon Cancer Patients in England

PURPOSE

Treatment with any adjuvant chemotherapy for stage III colon cancer has been shown to differ between population groups. Few studies, however, explore variations in the type of adjuvant chemotherapy received, none of which are from the UK. The aim of this study is to explore variation in the type of chemotherapy received by stage III colon cancer patients in England.

METHODS

Data from the national cancer registry was linked to the Systemic Anti-Cancer Therapy database, which provides detailed information on treatment of malignant diseases from all NHS England chemotherapy providers. Demographic and clinical characteristics were compared between those who received monotherapy (fluoropyrimidine) or combination chemotherapy (fluoropyrimidine and oxaliplatin) among stage III colon cancer patients between 2012 and 2017.

RESULTS

Of 8750 patients who received adjuvant chemotherapy, 22.3% (n = 2359) received monotherapy and 60.4% (n = 6391) received combination therapy. The odds of receiving combination therapy decreased with age. Those from the most deprived group had half the odds (OR: 0.5, CI: 0.42, 0.59, p < 0.001) of receiving combination therapy compared to the least deprived group. Women were 14% less likely to get combined therapy (OR: 0.86, CI: 0.77, 0.95, p = 0.005). Those with the largest tumour size (T4) and those with more than three lymph nodes involved (N2) had 30% (OR: 1.30; CI: 1.07, 1.59; p = 0.008) and 50% (OR: 1.50; 1.34, 1.69; p < 0.001) higher odds of receiving combination therapy compared to T1 or T2 and N1, respectively.

CONCLUSION

There is variation in the type of chemotherapy received for stage III colon cancer patients by sociodemographic factors, despite clear clinical guidelines.

Adjuvant chemotherapy non-adherence, patient-centered communication, and patient-level factors in elderly breast and colon cancer patients

BACKGROUND

We examined patient-level factors (patient characteristics, disease and treatment factors, and patient experience), patient-centered communication (PCCM), and non-adherence to adjuvant chemotherapy (AC) guidelines among breast and colon cancer patients to inform AC adherence promotion and improve clinical outcomes.

METHODS

Descriptive statistics for patient-level factors, PCCM, and AC non-adherence (primary non-adherence, non-persistence at 3 and 6 months) were obtained. Multiple logistic regression models were used to estimate AC non-adherence after accounting for the identified patient-level factors.

RESULTS

The majority of the sample (n = 577) were White (87%), breast cancer patients (87%), and reported PCCM (provider communication score ≥ 90%, 73%, provider communication score = 100%, 58%). All three levels of AC nonadherence were significantly higher in breast cancer patients (69%, 81%, and 89% for primary non-adherence, and non-persistence at 3 and 6 months, respectively) than colon cancer patients (43%, 46%, and 62%, respectively). Male sex, survey assistance, and low/average ratings of a personal doctor, specialist, and healthcare were associated with lower PCCM. Older age, breast cancer diagnosis, and diagnosis group following 2007-2009 increased the likelihood of all three levels of AC non-adherence. Comorbidities and PCCM-90 were exclusively associated with non-persistence at 3 months.

CONCLUSIONS

Adjuvant chemotherapy non-adherence varied by cancer diagnosis and treatment factors. The relationship between PCCM and AC non-adherence differed by level of PCCM, time period, and the presence of comorbidities. AC guideline adherence, communication, and value-concordant treatment should be assessed and compared simultaneously to improve our understanding of their interrelationships.

Trends and disparities in the utilization of systemic chemotherapy in patients with metastatic hepato-pancreato-biliary cancers

BACKGROUND

We described trends and disparities in utilization of systemic chemotherapy in metastatic hepato-pancreato-biliary (HPB) cancers.

METHODS

We queried the National Cancer Database for metastatic HPB cancers [hepatocellular carcinoma (HCC), biliary tract cancers (BTC), pancreatic adenocarcinoma (PDAC)]. We used multivariable analysis to examine the factors associated with utilization of systemic chemotherapy. We utilized marginal structural logistic models to estimate the effect of health insurance, facility type, or facility volume on utilization of systemic chemotherapy.

RESULTS

We identified 162,283 patients with metastatic HPB cancers: 23,923 (14.7%) had HCC, 26,766 (16.5%) had BTC, and 111,594 (68.8%) had PDAC. A total of 37.2% patients with HCC, 55.6% with BTC, and 56.4% with PDAC received chemotherapy. Age ≥70 years and Charlson-Deyo score ≥2 were associated with lower likelihood of receiving chemotherapy across all cancers. Patients with private health insurance had higher receipt of chemotherapy. Receiving treatment at academic facilities had no effect on the receipt of chemotherapy. Treatment of patients with HCC or PDAC at high-volume facilities resulted in higher receipt of chemotherapy.

CONCLUSION

A significant proportion of patients with metastatic HPB cancers do not receive systemic chemotherapy. Several disparities in administration of chemotherapy for metastatic HPB cancers exist.

Trends in Adjuvant Chemotherapy Use Among Stage III Colon Cancer in Non-Elderly and Low Comorbidity Patients

BACKGROUND

Adjuvant chemotherapy for stage III colon cancer is underutilized in the United States. The aim of this study was to assess the use of adjuvant chemotherapy in younger and medically fit patients and analyze the socioeconomic factors associated with its utilization.

METHODS

Using the National Cancer Database from 2004 to 2015, we selected stage III colon cancer patients between age 18 to 65, Charlson-Deyo Comorbidity Index (CDCI) of 0 or 1, and those that survived at least 12 months after surgery. We then compared patients that underwent surgery only with those that received adjuvant chemotherapy. Multivariable logistic regression analysis was performed to identify variables associated with adjuvant chemotherapy use in the population. Overall survival was estimated by Kaplan-Meier curves.

RESULTS

Of the 48,336 patients that met inclusion criteria, 43,315 (90%) received adjuvant chemotherapy. The utilization of adjuvant chemotherapy increased from 87% in 2004 to 91% in 2015. On multivariable regression analysis, the use of adjuvant chemotherapy was lower among males, Non-Hispanic Blacks and Hispanics, low-grade cancer, left-sided tumors, CDCI 1, those who travel ≥ 50 miles, yearly income < $40,227, and uninsured patients. The most common reason for the omission of adjuvant chemotherapy was the patient or caregiver's choice (40% between 2013 and 2015). The 5-year and 10-year overall survival rates were 76.7% and 63.8% respectively, in those who received adjuvant chemotherapy as compared to 65.1% and 49.3% in those who underwent surgery only (P < .001).

CONCLUSION

In young and medically fit stage III colon cancer patients, most patients received guideline-compliant care in the United States. However, socioeconomic disparities adversely impacted the use of adjuvant chemotherapy. The patient or caregiver's decision was the most common reason for non-adherence to adjuvant chemotherapy and lead to poor survival outcomes. Emphasis should be placed on developing patient-centered strategies to improve adherence to chemotherapy in all patients.

Circulating Tumor DNA in Stage III Colorectal Cancer, beyond Minimal Residual Disease Detection, toward Assessment of Adjuvant Therapy Efficacy and Clinical Behavior of Recurrences

PURPOSE

Sensitive methods for risk stratification, monitoring therapeutic efficacy, and early relapse detection may have a major impact on treatment decisions and patient management for stage III colorectal cancer patients. Beyond assessing the predictive power of postoperative ctDNA detection, we explored the added benefits of serial analysis: assessing adjuvant chemotherapy (ACT) efficacy, early relapse detection, and ctDNA growth rates.

EXPERIMENTAL DESIGN

We recruited 168 patients with stage III colorectal cancer treated with curative intent at Danish and Spanish hospitals between 2014 and 2019. To quantify ctDNA in plasma samples (n = 1,204), 16 patient-specific somatic single-nucleotide variants were profiled using multiplex-PCR, next-generation sequencing.

RESULTS

Detection of ctDNA was a strong recurrence predictor postoperatively [HR = 7.0; 95% confidence interval (CI), 3.7-13.5; P < 0.001] and directly after ACT (HR = 50.76; 95% CI, 15.4-167; P < 0.001). The recurrence rate of postoperative ctDNA-positive patients treated with ACT was 80% (16/20). Only patients who cleared ctDNA permanently during ACT did not relapse. Serial ctDNA assessment after the end of treatment was similarly predictive of recurrence (HR = 50.80; 95% CI, 14.9-172; P < 0.001), and revealed two distinct rates of exponential ctDNA growth, slow (25% ctDNA-increase/month) and fast (143% ctDNA-increase/month; P < 0.001). The ctDNA growth rate was prognostic of survival (HR = 2.7; 95% CI, 1.1-6.7; P = 0.039). Serial ctDNA analysis every 3 months detected recurrence with a median lead-time of 9.8 months compared with standard-of-care computed tomography.

CONCLUSIONS

Serial postoperative ctDNA analysis has a strong prognostic value and enables tumor growth rate assessment. The novel combination of ctDNA detection and growth rate assessment provides unique opportunities for guiding decision-making.See related commentary by Morris and George, p. 438.

Racial Disparities in the Management of Locoregional Colorectal Cancer

Racial disparities pervade nearly all aspects of management of locoregional colorectal cancer, including time to treatment, receipt of resection, adequacy of resection, postoperative complications, and receipt of neoadjuvant and adjuvant multimodality therapies. Disparate gaps in treatment translate into enduring effects on survivorship, recurrence, and mortality. Efforts to reduce these gaps in care must be undertaken on a multilevel basis and focus on modifiable factors that underlie racial disparity.

Patient Factors Limit Colon Cancer Survival at Safety-Net Hospitals: A National Analysis

BACKGROUND

Safety-net hospitals serve a vital role in society by providing care for vulnerable populations. Existing data regarding oncologic outcomes of patients with colon cancer treated at safety-net hospitals are limited and variable. The objective of this study was to delineate disparities in treatment and outcomes for patients with colon cancer treated at safety-net hospitals.

METHODS

This retrospective cohort study identified 802,304 adult patients with colon adenocarcinoma from the National Cancer Database between 2004-2016. Patients were stratified according to safety-net burden of the treating hospital as previously described. Patient, tumor, facility, and treatment characteristics were compared between groups as were operative and short-term outcomes. Cox proportional hazards regression was utilized to compare overall survival between patients treated at high, medium, and low burden hospitals.

RESULTS

Patients treated at safety-net hospitals were demographically distinct and presented with more advanced disease. They were also less likely to receive surgery, adjuvant chemotherapy, negative resection margins, adequate lymphadenectomy, or a minimally invasive operative approach. On multivariate analysis adjusting for patient and tumor characteristics, survival was inferior for patients at safety-net hospitals, even for those with stage 0 (in situ) disease.

CONCLUSION

This analysis revealed inferior survival for patients with colon cancer treated at safety-net hospitals, including those without invasive cancer. These findings suggest that unmeasured population differences may confound analyses and affect survival more than provider or treatment disparities.

HERVs establish a distinct molecular subtype in stage II/III colorectal cancer with poor outcome

Colorectal cancer (CRC) is one of the most lethal malignancies. The extreme heterogeneity in survival rate is driving the need for new prognostic biomarkers. Human endogenous retroviruses (hERVs) have been suggested to influence tumor progression, oncogenesis and elicit an immune response. We examined multiple next-generation sequencing (NGS)-derived biomarkers in 114 CRC patients with paired whole-exome and whole-transcriptome sequencing (WES and WTS, respectively). First, we demonstrate that the median expression of hERVs can serve as a potential biomarker for prognosis, relapse, and resistance to chemotherapy in stage II and III CRC. We show that hERV expression and CD8+ tumor-infiltrating T-lymphocytes (TILs) synergistically stratify overall and relapse-free survival (OS and RFS): the median OS of the CD8-/hERV+ subgroup was 29.8 months compared with 37.5 months for other subgroups (HR = 4.4, log-rank P < 0.001). Combing NGS-based biomarkers (hERV/CD8 status) with clinicopathological factors provided a better prediction of patient survival compared to clinicopathological factors alone. Moreover, we explored the association between genomic and transcriptomic features of tumors with high hERV expression and establish this subtype as distinct from previously described consensus molecular subtypes of CRC. Overall, our results underscore a previously unknown role for hERVs in leading to a more aggressive subtype of CRC.

Prognostic and Predictive Cross-Roads of Microsatellite Instability and Immune Response to Colon Cancer

Understanding molecular features of colon cancer has shed light on its pathogenesis and progression. Over time, some of these features acquired clinical dignity and were incorporated in decision making. Namely, microsatellite instability (MSI) due to mismatch repair of defects, which primarily was adopted for the diagnosis of Lynch syndrome, became recognized as the biomarker of a different disease type, showing a less aggressive behavior. MSI tumors harbor high amounts of tumor infiltrating lymphocytes (TILs) due to their peculiar load in neoantigens. However, microsatellite stable colon cancer may also show high amounts of TILs, and this feature is as well associated with better outcomes. High TIL loads are in general associated with a favorable prognosis, especially in stage II colon cancer, and therein identifies a patient subset with the lowest probability of relapse. With respect to post-surgical adjuvant treatment, particularly in stage III, TILs predictive ability seems to weaken along with the progression of the disease, being less evident in high risk patients. Moving from cohort studies to the analysis of a series from clinical trials contributed to increase the robustness of TILs as a biomarker. The employment of high TIL densities as an indicator of good prognosis in early-stage colon cancers is strongly advisable, while in late-stage colon cancers the employment as an indicator of good responsiveness to post-surgical therapy requires refinement. It remains to be clarified whether TILs could help in identifying those patients with node-positive cancers to whom adjuvant treatment could be spared, at least in low-risk groups as defined by the TNM staging system.

The influence of socioeconomic position on adjuvant treatment of stage III colon cancer: a systematic review and meta-analysis

BACKGROUND

Patients with colon cancer (CC) with low socioeconomic position (SEP) have a worse survival than patients with high SEP. We investigated the association between different socioeconomic indicators and the steps in the treatment trajectory leading to initiation of adjuvant chemotherapy (ACT) for patients with stage III CC.

MATERIALS AND METHODS

A systematic review and meta-analyses were conducted in accordance with the MOOSE checklist. MEDLINE and EMBASE were searched for eligible studies. Meta-analyses were performed on the separate socioeconomic indicators with the random-effects model. The heterogeneity across studies was assessed by the Q and the I ² statistic.

RESULTS

In total, 27 observational studies were included. SEP was measured by insurance, income, poverty, employment, education, or an index on an area or individual level. SEP, regardless of indicator, was negatively associated with the steps in the treatment trajectory leading to initiation of ACT among patients with resected stage III CC. The meta-analyses showed that patients with low SEP had a significantly lower odds of receiving ACT and increased odds of delayed treatment start, whereas SEP had no impact on the choice of therapy: combination or single-agent therapy.

CONCLUSION

SEP was associated with less initiation of and higher risk for delayed initiation of ACT. Our findings suggest there is a social disparity in receipt of ACT in patients with stage III CC.

Multicenter International Society for Immunotherapy of Cancer Study of the Consensus Immunoscore for the Prediction of Survival and Response to Chemotherapy in Stage III Colon Cancer

PURPOSE

The purpose of this study was to evaluate the prognostic value of Immunoscore in patients with stage III colon cancer (CC) and to analyze its association with the effect of chemotherapy on time to recurrence (TTR).

METHODS

An international study led by the Society for Immunotherapy of Cancer evaluated the predefined consensus Immunoscore in 763 patients with American Joint Committee on Cancer/Union for International Cancer Control TNM stage III CC from cohort 1 (Canada/United States) and cohort 2 (Europe/Asia). CD3+ and cytotoxic CD8+ T lymphocyte densities were quantified in the tumor and invasive margin by digital pathology. The primary end point was TTR. Secondary end points were overall survival (OS), disease-free survival (DFS), prognosis in microsatellite stable (MSS) status, and predictive value of efficacy of chemotherapy.

RESULTS

Patients with a high Immunoscore presented with the lowest risk of recurrence, in both cohorts. Recurrence-free rates at 3 years were 56.9% (95% CI, 50.3% to 64.4%), 65.9% (95% CI, 60.8% to 71.4%), and 76.4% (95% CI, 69.3% to 84.3%) in patients with low, intermediate, and high immunoscores, respectively (hazard ratio [HR; high v low], 0.48; 95% CI, 0.32 to 0.71; P = .0003). Patients with high Immunoscore showed significant association with prolonged TTR, OS, and DFS (all P < .001). In Cox multivariable analysis stratified by participating center, Immunoscore association with TTR was independent (HR [high v low], 0.41; 95% CI, 0.25 to 0.67; P = .0003) of patient's sex, T stage, N stage, sidedness, and microsatellite instability status. Significant association of a high Immunoscore with prolonged TTR was also found among MSS patients (HR [high v low], 0.36; 95% CI, 0.21 to 0.62; P = .0003). Immunoscore had the strongest contribution χ2 proportion for influencing survival (TTR and OS). Chemotherapy was significantly associated with survival in the high-Immunoscore group for both low-risk (HR [chemotherapy v no chemotherapy], 0.42; 95% CI, 0.25 to 0.71; P = .0011) and high-risk (HR [chemotherapy v no chemotherapy], 0.5; 95% CI, 0.33 to 0.77; P = .0015) patients, in contrast to the low-Immunoscore group (P > .12).

CONCLUSION

This study shows that a high Immunoscore significantly associated with prolonged survival in stage III CC. Our findings suggest that patients with a high Immunoscore will benefit the most from chemotherapy in terms of recurrence risk.

Refusal of cancer-directed treatment by colon cancer patients: Risk factors and survival outcomes

AIM

Surgery with or without chemotherapy represent the only curative option for patients with colon cancer. However, some patients refuse treatment despite the recommendation. This study aims to identify the incidence, risk factors and impact on survival associated with refusal.

METHODS

A National Cancer Data Base (NCDB) analysis between 1998 and 2012 was performed. We identified 924,290 patients with potentially treatable colon cancer. Patients who underwent treatment were compared with patients that refused.

RESULTS

7152 patients refused surgery. On multivariable analysis, patients were more likely to refuse if they were older (OR = 1.14; 95% CI 1.14-1.15), female (OR = 1.20; 95% CI 1.12-1.28), African American (vs White, OR = 2.30; 95% CI 2.10-2.51) or on Medicaid (vs private, OR = 3.06; 95% CI 2.49-43.77). Overall survival was worse in patients that refused surgery [median survival 6.8 vs 24 months, Cox hazard ratio (HR) 3.41; 95%CI 3.12-3.60]. Furthermore, 11,334 patients with path. stage III disease refused adjuvant chemotherapy.

CONCLUSIONS

Refusal of treatment affects survival and is independently associated with several variables (gender, race, insurance status), therefore raising the concern that socioeconomic factors may drive decisions.

Analysis of Plasma Cell-Free DNA by Ultradeep Sequencing in Patients With Stages I to III Colorectal Cancer

Importance

Novel sensitive methods for detection and monitoring of residual disease can improve postoperative risk stratification with implications for patient selection for adjuvant chemotherapy (ACT), ACT duration, intensity of radiologic surveillance, and, ultimately, outcome for patients with colorectal cancer (CRC).

Objective

To investigate the association of circulating tumor DNA (ctDNA) with recurrence using longitudinal data from ultradeep sequencing of plasma cell-free DNA in patients with CRC before and after surgery, during and after ACT, and during surveillance.

Design, Setting, and Participants

In this prospective, multicenter cohort study, ctDNA was quantified in the preoperative and postoperative settings of stages I to III CRC by personalized multiplex, polymerase chain reaction-based, next-generation sequencing. The study enrolled 130 patients at the surgical departments of Aarhus University Hospital, Randers Hospital, and Herning Hospital in Denmark from May 1, 2014, to January 31, 2017. Plasma samples (n = 829) were collected before surgery, postoperatively at day 30, and every third month for up to 3 years.

Main Outcomes and Measures

Outcomes were ctDNA measurement, clinical recurrence, and recurrence-free survival.

Results

A total of 130 patients with stages I to III CRC (mean [SD] age, 67.9 [10.1] years; 74 [56.9%] male) were enrolled in the study; 5 patients discontinued participation, leaving 125 patients for analysis. Preoperatively, ctDNA was detectable in 108 of 122 patients (88.5%). After definitive treatment, longitudinal ctDNA analysis identified 14 of 16 relapses (87.5%). At postoperative day 30, ctDNA-positive patients were 7 times more likely to relapse than ctDNA-negative patients (hazard ratio [HR], 7.2; 95% CI, 2.7-19.0; P < .001). Similarly, shortly after ACT ctDNA-positive patients were 17 times (HR, 17.5; 95% CI, 5.4-56.5; P < .001) more likely to relapse. All 7 patients who were ctDNA positive after ACT experienced relapse. Monitoring during and after ACT indicated that 3 of the 10 ctDNA-positive patients (30.0%) were cleared by ACT. During surveillance after definitive therapy, ctDNA-positive patients were more than 40 times more likely to experience disease recurrence than ctDNA-negative patients (HR, 43.5; 95% CI, 9.8-193.5 P < .001). In all multivariate analyses, ctDNA status was independently associated with relapse after adjusting for known clinicopathologic risk factors. Serial ctDNA analyses revealed disease recurrence up to 16.5 months ahead of standard-of-care radiologic imaging (mean, 8.7 months; range, 0.8-16.5 months). Actionable mutations were identified in 81.8% of the ctDNA-positive relapse samples.

Conclusions and Relevance

Circulating tumor DNA analysis can potentially change the postoperative management of CRC by enabling risk stratification, ACT monitoring, and early relapse detection.

RNA sequencing reveals PNN and KCNQ1OT1 as predictive biomarkers of clinical outcome in stage III colorectal cancer patients treated with adjuvant chemotherapy

Five-year overall survival of stage III colorectal cancer (CRC) patients treated with standard adjuvant chemotherapy (ACHT) is highly variable. Genomic biomarkers and/or transcriptomic profiles identified lack of adequate validation. Aim of our study was to identify and validate molecular biomarkers predictive of ACHT response in stage III CRC patients by a transcriptomic approach. From a series of CRC patients who received ACHT, two stage III extreme cohorts (unfavorable vs. favorable prognosis) were selected. RNA-sequencing was performed from fresh frozen explants. Tumors were characterized for somatic mutations. Validation was performed in stage III CRC patients extracted from two GEO datasets. According to disease-free survival (DFS), 108 differentially expressed genes (104/4 up/downregulated in the unfavorable prognosis group) were identified. Among 104 upregulated genes, 42 belonged to olfactory signaling pathways, 62 were classified as pseudogenes (n = 17), uncharacterized noncoding RNA (n = 10), immune response genes (n = 4), microRNA (n = 1), cancer-related genes (n = 14) and cancer-unrelated genes (n = 16). Three out of four down-regulated genes were cancer-related. Mutational status (i.e., RAS, BRAF, PIK3CA) did not differ among the cohorts. In the validation cohort, multivariate analysis showed high PNN and KCNQ1OT1 expression predictive of shorter DFS in ACHT treated patients (p = 0.018 and p = 0.014, respectively); no difference was observed in untreated patients. This is the first study that identifies by a transcriptomic approach and validates PNN and KCNQ1OT1 as molecular biomarkers predictive of chemotherapy response in stage III CRC patients. After a further validation in an independent cohort, PNN and KCNQ1OT1 evaluation could be proposed to prospectively identify stage III CRC patients benefiting from ACHT.

Serum Concentration of Genistein, Luteolin and Colorectal Cancer Prognosis

Although flavonoid phytoestrogens have been suggested to be associated with reduced risk of colorectal cancer (CRC), their influence on CRC prognosis remains uncertain. A population-based cohort of 2051 patients diagnosed with stage I⁻III CRC in southwest Germany in 2003⁻2010 were followed for five years. Post-diagnostic serum concentration of genistein and luteolin were measured using Ultra-Performance Liquid Chromatography with mass spectrometry. Multivariable Cox regression analysis was conducted to calculate the Hazard Ratios (HRs) and 95% confidence interval (CI) for the association between flavonoids concentration and overall morality, CRC-specific mortality, CRC recurrence, and disease-free survival (DFS). Median (interquartile range) serum concentration of genistein and luteolin was 11.90 ng/µL (10.08⁻14.13) and 7.20 ng/µL (6.40⁻8.16), respectively. Neither serum genistein nor luteolin was associated with CRC prognosis. There was no clear evidence of departure from linearity. However, the association might be differential by adjuvant chemotherapy. Associations pointed towards lower risk in patients who received chemotherapy and higher risk in those without chemotherapy for overall mortality regarding serum genistein (P-interaction = 0.02) and correspondingly for CRC recurrence (P-interaction: 0.03) and DFS (P-interaction: 0.01) with respect to luteolin. Our study provides little evidence that serum genistein and luteolin are associated with colorectal cancer prognosis. Future studies are warranted to evaluate the potential interaction with adjuvant chemotherapy.

Association Between Primary Payer Status and Survival in Patients With Stage III Colon Cancer: An National Cancer Database Analysis

BACKGROUND

Colon cancer is the third most frequent cancer diagnosis, and primary payer status has been shown to be associated with treatment modalities and survival in cancer patients. The goal of our study was to determine the between-insurance differences in survival in patients with clinical stage III colon cancer using data from the National Cancer Database (NCDB).

MATERIALS AND METHODS

We identified 130,998 patients with clinical stage III colon cancer in the NCDB diagnosed from 2004 to 2012. Kaplan-Meier curves and multivariable Cox regression models were used to determine the association between insurance status and survival.

RESULTS

Patients with private insurance plans were 28%, 30%, and 16% less likely to die than were uninsured patients, Medicaid recipients, and Medicare beneficiaries, respectively. Medicare patients were 14% were less likely to die compared with uninsured patients. Patients receiving chemotherapy were, on average, 65% less likely to die compared with the patients not receiving chemotherapy.

CONCLUSION

Private insurance and a greater socioeconomic status were associated with increased patient survival compared with other insurance plans or the lack of insurance. Future research should continue to unravel how socioeconomic status and insurance status contribute to the quality of care and survival of oncologic patients.

Prognostic impact of interhospital variation in adjuvant chemotherapy for patients with Stage II/III colorectal cancer: a nationwide study

AIM

Clinical guidelines recommend adjuvant chemotherapy for high-risk patients with Stage II-III colorectal cancer. However, chemotherapeutic administration rates differ significantly between hospitals. We assessed the prognostic benefit of adjuvant chemotherapy in patients with Stage IIb/c colorectal cancer, and the prognostic impact of interhospital variations in the administration of adjuvant chemotherapy for Stage II-III colorectal cancer.

METHOD

We conducted a multicentre, retrospective study of 17 757 patients with Stage II-III colorectal cancer treated between 1997 and 2008 in 23 hospitals in Japan. Hospitals were classified as high-rate (rate > 42.8%) or low-rate (rate ≤ 42.8%), chemotherapy prescribing clinics.

RESULTS

The 5-year overall survival (OS) of patients with Stage II-III colorectal cancer receiving adjuvant chemotherapy was significantly higher than for those not receiving adjuvant chemotherapy (85.7% vs 79.2%, P < 0.01 and 79.9% vs 72.5%, P < 0.01, respectively). For patients with Stage II disease, adjuvant chemotherapy was an independent factor for longer OS (P < 0.01, hazard ratio = 0.71). Both adjuvant chemotherapy and high-rate hospital independently improved OS for patients with Stage III colorectal cancer (both P < 0.01; hazard ratio = 0.68 and 0.87, respectively).

CONCLUSION

Significant prognostic benefit was found for patients with Stage IIb/c colorectal cancer who received adjuvant chemotherapy, with patients who were treated in hospitals with high adjuvant chemotherapy rates demonstrating better prognoses.

The accuracy of chemotherapy ascertainment among colorectal cancer patients in the surveillance, epidemiology, and end results registry program

BACKGROUND

Surveillance, Epidemiology, and End Results (SEER) public research database does not include chemotherapy data due to concerns for incomplete ascertainment. To compensate for perceived lack of data quality many researchers use SEER-Medicare linked data, limiting studies to persons over age 65. We sought to determine current SEER ascertainment of chemotherapy receipt in two relatively large SEER registries compared to patient-reported receipt and to assess patterns of under-ascertainment.

METHODS

In 2011-14, we surveyed patients with Stage III colorectal cancer reported to the Georgia and Metropolitan Detroit SEER registries. 1301/1909 eligible patients responded (68% response rate). Survey responses regarding treatment and sociodemographic factors were merged with SEER data. We compared patient-reported chemotherapy receipt with SEER recorded chemotherapy receipt. We estimated multivariable regression models to assess associations of under-ascertainment in SEER.

RESULTS

Eighty-five percent of patients reported chemotherapy receipt. Among those, 10% (n = 104) were under-ascertained in SEER (coded as not receiving chemotherapy). In unadjusted analyses, under-ascertainment was more common for older patients (11.8% age 76+ vs. < 9% for all other ages, p = 0.01) and varied with SEER registries (10.2% Detroit vs. 6.8% Georgia; p = 0.04). On multivariable analyses, chemotherapy under-ascertainment did not vary significantly by any patient attributes.

CONCLUSION

We found a 10% rate of under-ascertainment of adjuvant chemotherapy for resected, stage III colorectal cancer in two SEER registries. Chemotherapy under-ascertainment did not disproportionately affect any patient subgroups. Use of SEER data from select registries is an important resource for researchers investigating contemporary chemotherapy receipt and outcomes.

Use of adjuvant chemotherapy in patients with stage III colon cancer in Puerto Rico: A population-based study

Objective

This study aims to examine factors associated with the use of adjuvant chemotherapy and the use of oxaliplatin after curative resection in stage III colon cancer patients and assesses the effect of their use in three-year survival.

Methods

This retrospective cohort study was conducted using Puerto Rico Central Cancer Registry-Health Insurance Linkage Database. The study cohort consisted of stage III colon cancer patients with a curative surgery in the period 2008–2012. Multivariate logistic regression was used to estimate adjusted odds ratios. Kaplan-Meier methods and Cox proportional hazards models were used to assess the association between adjuvant chemotherapy and oxaliplatin use and overall survival and risk of death, respectively.

Results

Overall, 75% of the study population received adjuvant chemotherapy during the study period. Factors statistically associated with receiving adjuvant chemotherapy within four months after resection included being married (adjusted odds ratio [AOR] 1.64; 95% CI 1.18–2.28; p = 0.003), and being enrolled in Medicare (AOR 1.68; 95% CI: 1.03–2.75; p = 0.039) or Medicaid and Medicare dual eligible (AOR 1.66; 95% CI: 1.06–2.60; p = 0.028). However, patients aged ≥70 years were less likely to receive adjuvant chemotherapy (AOR 0.22; 95%CI 0.14–0.36; p<0.001).

Discussion

We observed a significant reduction in mortality in adjuvant chemotherapy treated patients. Similarly, patients <70 years treated with oxaliplatin had significantly lower risk of death than those who did not, although for patients ≥70 years no statistical significance was achieved. Future studies should assess effective interventions to reduce barriers to access guideline-based recommended colon cancer treatment.

Investigation of treatment pattern, medical resource utilization and demographic prognostic factors in older patients with non-Hodgkin lymphoma: A nationwide population-based study

BACKGROUND

This nationwide population study aimed to investigate treatment patterns, medical resource utilization and demographic prognostic factors in older Taiwanese patients with non-Hodgkin lymphoma (NHL).

PATIENTS AND METHODS

This study was conducted using the National Health Insurance Research Database (NHIRD) of Taiwan. The older patients (65years or older) diagnosed with NHL between 1997 and 2008 were identified for analysis.

RESULTS

A total of 5136 patients (3049 males and 2087 females) with a median age of 74.1years were identified for analysis. Among these patients, 3267 patients (63.6%) received various combinations of systemic therapies. The older the patient, the less likely it was for intensive curative treatment to be given. Regarding medical resource usage, younger patients or patients living in more urbanized areas were more likely to receive NHL treatment in medical centers. The median overall survival of all patients with NHL was 49.41months (range, 0.03 to 143.97). The investigation for prognostic factors by multivariate analysis revealed that more advanced age, treatment in non-medical centers and living in less urbanized areas were associated with poorer outcomes.

CONCLUSION

Treatment of older patients with NHL is still a challenge. For better outcomes, it is very important to evaluate the patient and tailor treatment modalities. Additionally, health policy makers should help to narrow discrepancies in survival based on demographics.