Prognosis after rectal cancer in blacks and whites participating in adjuvant therapy randomized trials

Factors Associated With Racial and Ethnic Disparities in Locally Advanced Rectal Cancer Outcomes

Importance

Hispanic and non-Hispanic Black patients receiving neoadjuvant therapy and surgery for locally advanced rectal cancer (LARC) achieve less favorable clinical outcomes than non-Hispanic White patients, but the source of this disparity is incompletely understood.

Objective

To assess whether racial and ethnic disparities in treatment outcomes among patients with LARC could be accounted for by social determinants of health and demographic, clinical, and pathologic factors known to be associated with treatment response.

Design, Setting, and Participants

The National Cancer Database was interrogated to identify patients with T3 to T4 or N1 to N2 LARC treated with neoadjuvant therapy and surgery. Patients were diagnosed between January 1, 2004, and December 31, 2017. Data were culled from the National Cancer Database from July 1, 2022, through December 31, 2023.

Exposure

Neoadjuvant therapy for rectal cancer followed by surgical resection.

Main Outcomes and Measures

The primary outcome was the rate of pathologic complete response (pCR) following neoadjuvant therapy. Secondary outcomes were rate of tumor downstaging and achievement of pN0 status.

Results

A total of 34 500 patient records were reviewed; 21 679 of the patients (62.8%) were men and 12 821 (37.2%) were women. The mean (SD) age at diagnosis was 59.7 (12.0) years. In terms of race and ethnicity, 2217 patients (6.4%) were Hispanic, 2843 (8.2%) were non-Hispanic Black, and 29 440 (85.3%) were non-Hispanic White. Hispanic patients achieved tumor downstaging (48.9% vs 51.8%; P = .01) and pN0 status (66.8% vs 68.8%; P = .02) less often than non-Hispanic White patients. Non-Hispanic Black race, but not Hispanic ethnicity, was associated with less tumor downstaging (odds ratio [OR], 0.86 [95% CI, 0.78-0.94]), less frequent pN0 status (OR, 0.91 [95% CI, 0.83-0.99]), and less frequent pCR (OR, 0.81 [95% CI, 0.72-0.92]). Other factors associated with reduced rate of pCR included rural location (OR, 0.80 [95% CI, 0.69-0.93]), lack of or inadequate insurance (OR for Medicaid, 0.86 [95% CI, 0.76-0.98]; OR for no insurance, 0.65 [95% CI, 0.54-0.78]), and treatment in a low-volume center (OR for first quartile, 0.73 [95% CI, 0.62-0.87]; OR for second quartile, 0.79 [95% CI, 0.70-0.90]; OR for third quartile, 0.86 [95% CI, 0.78-0.94]). Clinical and pathologic variables associated with a decreased pCR included higher tumor grade (OR, 0.58 [95% CI, 0.49-0.70]), advanced tumor stage (OR for T3, 0.56 [95% CI, 0.42-0.76]; OR for T4, 0.30 [95% CI, 0.22-0.42]), and lymph node-positive disease (OR for N1, 0.83 [95% CI, 0.77-0.89]; OR for N2, 0.73 [95% CI, 0.65-0.82]).

Conclusions and Relevance

The findings of this cohort study suggest that disparate treatment outcomes for Hispanic and non-Hispanic Black patients are likely multifactorial in origin. Future investigation into additional social determinants of health and biological variables is warranted.

Diversity in modern heart failure trials: Where are we, and where are we going

Over the last three decades, increased attention has been given to the representation of historically underrepresented groups within the landscape of pivotal clinical trials. However, recent events (i.e., coronavirus pandemic) have laid bare the potential continuation of historic inequities in available clinical trials and studies aimed at the care of broad patient populations. Anecdotally, cardiovascular disease (CVD) has not been immune to these disparities. Within this review, we examine and discuss recent landmark CVD trials, with a specific focus on the representation of Blacks within several critically foundational heart failure clinical trials tied to contemporary treatment strategies and drug approvals. We also discuss solutions for inequities within the landscape of cardiovascular trials. Building a more diverse clinical trial workforce coupled with intentional efforts to increase clinical trial diversity will advance equity in cardiovascular care.

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.

Competitive Risk Analysis of Prognosis in Patients With Cecum Cancer: A Population-Based Study

Background:

The presence of competing risks means that the results obtained using the classic Cox proportional-hazards model for the factors affecting the prognosis of patients diagnosed with cecum cancer (CC) may be biased.

Objective:

The purpose of this study was to establish a competitive risk model for patients diagnosed with CC to evaluate the relevant factors affecting the prognosis of patients, and to compare the results with the classical COX proportional risk model.

Methods:

We extracted data on patients diagnosed with CC registered between 2004 and 2016 in the Surveillance, Epidemiology, and End Results (SEER) database. The univariate analysis utilized the cumulative incidence function and Gray’s test, while a multivariate analysis was performed using the Fine-Gray, cause-specific (CS), and Cox proportional-hazards models.

Results:

The 54463 eligible patients diagnosed with CC included 24387 who died: 12087 from CC and 12300 from other causes. The multivariate Fine-Gray analysis indicated that significant factors affecting the prognosis of patients diagnosed with CC include: age, race, AJCC stage, differentiation grade, tumor size, surgery, radiotherapy, chemotherapy and regional lymph nodes metastasis. Due to the presence of competitive risk events, COX model results could not provide accurate estimates of effects and false-negative results occurred. In addition, COX model misestimated the direction of association between regional lymph node metastasis and cumulative risk of death in patients diagnosed with CC. Competitive risk models tend to be more advantageous when analyzing clinical survival data with multiple endpoints.

Conclusions:

The present study can help clinicians to make better clinical decisions and provide patients diagnosed with CC with better support.

A step towards equitable clinical trial recruitment: a protocol for the development and preliminary testing of an online prostate cancer health information and clinical trial matching tool

Background

Recruitment of a diverse participant pool to cancer clinical trials is an essential component of clinical research as it improves the generalizability of findings. Investigating and piloting novel recruitment strategies that take advantage of ubiquitous digital technologies has become an important component of facilitating broad recruitment and addressing inequities in clinical trial participation. Equitable and inclusive recruitment improves generalizability of clinical trial outcomes, benefiting patients, clinicians, and the research community. The increasing prevalence of online connectivity in the USA and use of the Internet as a resource for medical information provides an opportunity for digital recruitment strategies in cancer clinical trials. This study aims to measure the acceptability, preliminary estimates of efficacy, and feasibility of the Trial Library intervention, an Internet-based cancer clinical trial matching tool. This study will also examine the extent to which the Trial Library website, designed to address the linguistic and literacy needs of broader patient populations, influences patient-initiated conversations with physicians about clinical trial participation.

Methods

This is a study protocol for a non-randomized, single-arm pilot study. This is a mixed methods study design that utilizes the statistical analysis of quantitative survey data and the qualitative analysis of interview data to assess the participant experience with the Trial Library intervention. This study will examine (1) acceptability as a measure of participant satisfaction with this intervention, (2) preliminary measure of efficacy as a measure of proportion of participants with documented clinical trial discussion in the electronic medical record, and (3) feasibility of the intervention as a measure of duration of clinical visit.

Discussion

The principles that informed the design of the Trial Library intervention aim to be generalizable to clinical trials across many disease contexts. From the ground up, this intervention is built to be inclusive of the linguistic, literacy, and technological needs of underrepresented patient populations. This study will collect essential preliminary data prior to a multi-site randomized clinical trial of the Trial Library intervention.

Trial registration

This study has received institutional approval from the Committee of Human Subjects Research at the University of California, San Francisco.

Racial disparities in preoperative chemotherapy use in gastric cancer patients in the United States: Analysis of the National Cancer Data Base, 2006-2014

BACKGROUND

No studies have investigated whether race/ethnicity is associated with the recommended use of preoperative chemotherapy or subsequent outcomes in gastric cancer. To determine whether there is such an association, analyses of patients with gastric cancer in the National Cancer Data Base (NCDB) were performed.

METHODS

Patients with clinical T2-4bN0-1M0 gastric adenocarcinoma, as defined by the eighth edition of the American Joint Committee on Cancer staging manual, who underwent gastrectomy from 2006 to 2014 were identified from the NCDB. Multiple logistic regression was conducted to examine factors associated with preoperative chemotherapy use.

RESULTS

This study identified 16,945 patients who met the criteria, and 8286 of these patients (49%) underwent preoperative chemotherapy. The use of preoperative chemotherapy remarkably increased over the study period, from 34% in 2006 to 65% in 2014. Preoperative chemotherapy was more commonly used for cardia tumors than noncardia tumors (83% vs 44% in 2014). In a multivariable analysis, races and ethnicities other than non-Hispanic (NH) white race were associated with less frequent use of preoperative chemotherapy in comparison with NH whites after adjustments for social, tumor, and hospital factors. The insurance status and the education level mediated an enhanced effect of racial/ethnic disparities in preoperative chemotherapy use. The use of preoperative chemotherapy and radiation therapy was associated with reduced racial/ethnic disparities in overall survival.

CONCLUSIONS

Racial/ethnic disparities in the use of preoperative chemotherapy and in outcomes exist among patients with gastric cancer in the United States. Efforts to improve the access to high-quality cancer care in minority groups may reduce racial disparities in gastric cancer in the United States. Cancer 2018;124:998-1007. © 2018 American Cancer Society.

Adjuvant gemcitabine-docetaxel chemotherapy for stage I uterine leiomyosarcoma: Trends and survival outcomes

OBJECTIVE

To assess recent trends of administering adjuvant gemcitabine-docetaxel (GD) chemotherapy for Stage I uterine leiomyosarcoma, and to compare disease-free and overall survival between women who received and did not receive adjuvant GD chemotherapy.

METHODS

All patients diagnosed with Stage I uterine leiomyosarcoma in a California-Colorado population-based health plan inclusive of 2006-2013 were included in a retrospective cohort. Adjuvant GD chemotherapy rates, clinico-pathologic characteristics and survival estimates were assessed.

RESULTS

Of 111 women with Stage I uterine leiomyosarcoma, 33 received adjuvant GD (median 4cycles), 77 received no chemotherapy, and 1 patient excluded for non-GD chemotherapy. GD-chemotherapy and no-chemotherapy groups were similar with respect to age, stage (IA/IB), uterine weight, mitotic index, body mass index, and Charlson comorbidity score. Non-Hispanic white women were twice as likely to receive adjuvant chemotherapy as non-white or Hispanic women (37.7 vs. 17.1%, P=0.02). The proportion of women receiving adjuvant GD chemotherapy increased from 6.5% in 2006-2008 to 46.9% in 2009-2013 (P<0.001). There was no significance difference in unadjusted Kaplan-Meyer estimated disease-free (P=0.95) or overall survival (P=0.43) between GD-chemotherapy and no-chemotherapy cohorts. Corresponding adjusted Cox proportional hazard ratios for adjuvant GD chemotherapy compared to no chemotherapy were 1.01 (95% confidence interval [CI] 0.57-1.80, P=0.97) for recurrence and 1.28 (95% CI 0.69-2.36, P-0.48) for mortality.

CONCLUSIONS

Use of adjuvant GD chemotherapy for Stage I uterine leiomyosarcoma has increased significantly in the last decade, despite unclear benefit. Compared to no chemotherapy, 4-6cycles of adjuvant GD chemotherapy does not appear to alter survival outcomes.

Lack of Association between an XRCC1 Gene Polymorphism and Colorectal Cancer Survival in Thailand

BACKGROUND

Colorectal cancer (CRC) is one of the most common causes of death worldwide and in Thailand. The X-ray repair cross-complementary protein 1 (XRCC1) is required for efficient DNA repair. The effects of this gene on survival in colorectal cancer remain controversial and have not been reported in Thailand. The aim of this study was to investigate the association of the XRCC1 gene with survival of colorectal cancer patients in a Thai population.

MATERIALS AND METHODS

Data and blood samples were collected from 255 newly diagnosed and pathologically confirmed CRC patients who were recruited during the period 2002 to 2006 and whose vital status was followed up until 31 October, 2014. Real-time PCR-HRM was used for genotype identification. The Kaplan-Meier method, the log-rank test, and Cox proportional hazard regression were used to estimate cumulative survival curves and compare various survival distributions and adjusted hazard ratios.

RESULTS

Most of the cases were males, and the median age was 55 years. The median survival time was 2.43 years. The cumulative 1-, 3-, 5-, 7-, and 10 year survival rates were 76.70%, 39.25%, 26.50%, 16.60% and 3.56%, respectively. After adjustment, female gender, ages 50-59 and ≥ 60 years, tumour stage III+IV, a signet-ring cell carcinoma, and poor differentiation had significant associations with increased risk of CRC death. While the XRCC1 Arg/Arg homozygote appeared to be a risk factor for CRC death, the association was not significant.

CONCLUSIONS

The genetic variant in the XRCC1 may not be associated with the survival of CRC patients in Thailand. Further studies are needed to verify our findings.

Enrollment Trends and Disparity Among Patients With Lung Cancer in National Clinical Trials, 1990 to 2012

Purpose Under-representation of elderly, women, and racial/ethnic minority patients with cancer in clinical trials is of national concern. The goal of this study was to characterize enrollment trends and disparities by age, sex, and race/ethnicity in lung cancer trials. Methods We analyzed data for 23,006 National Cancer Institute cooperative group lung cancer trial participants and 578,476 patients with lung cancer from the SEER registry from 1990 to 2012. The enrollment disparity difference (EDD) and enrollment disparity ratio (EDR) were calculated on the basis of the proportion of each subgroup in the trial population and the US lung cancer population. Annual percentage changes (APCs) in the subgroup proportions in each population were compared over time. Results Enrollment disparity for patients ≥ 70 years of age with non-small-cell lung cancer improved from 1990 to 2012 (test of parallelism, P = .020), with a remaining EDD of 0.22 (95% CI, 0.19 to 0.25) and EDR of 1.65 (95% CI, 1.51 to 1.82) in 2010 to 2012. No improvement was seen for elderly patients with small-cell lung cancer (SCLC), with an APC of 0.20 ( P = .714) among trial participants, despite a rising proportion of elderly patients with SCLC in the US population (APC, 0.32; P = .020). Enrollment disparity for women with lung cancer improved overall, with the gap closing by 2012 (EDD, 0.03 [95% CI, 0.00 to 0.06]; EDR, 1.07 [95% CI, 1.00 to 1.16]). Enrollment disparities persisted without significant improvement for elderly women, blacks, Asians/Pacific Islanders, and Hispanics. Conclusion Under-representation in lung cancer trials improved significantly from 1990 to 2012 for elderly patients with non-small-cell lung cancer and for women, but ongoing efforts to improve the enrollment of elderly patients with SCLC and minorities are needed. Our study highlights the importance of addressing enrollment disparities by demographic and disease subgroups to better target under-represented groups of patients with lung cancer.

Surveillance, epidemiology, and end results-based analysis of the impact of preoperative or postoperative radiotherapy on survival outcomes for T3N0 rectal cancer

PURPOSE

Preoperative chemoradiation has been established as standard of care for T3/T4 node-positive rectal cancer. Recent work, however, has called into question the overall benefit of radiation for tumors with lower risk characteristics, particularly T3N0 rectal cancers. We retrospectively analyzed T3N0 rectal cancer patients and examined how outcomes differed according to the sequence of treatment received.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to analyze T3N0 rectal cancer cases diagnosed between 1998 and 2008. Treatment consisted of surgery alone (No RT), preoperative radiation followed by surgery (Neo-Adjuvant RT), or surgery followed by postoperative radiation (Adjuvant RT). Demographic and tumor characteristics of the three groups were compared using t-tests for the comparison of means. Survival information from the SEER database was utilized to estimate cause-specific survival (CSS) and to generate Kaplan-Meier survival curves. Multivariate analysis (MVA) of features associated with outcomes was conducted using Cox proportional hazards regression models with Adjuvant RT, Neo-Adjuvant RT, No RT, histological grade, tumor size, year of diagnosis, and demographic characteristics as covariates.

RESULTS

10-Year CSS estimates were 66.1% (95% CI 62.3-69.6%; P=0.02), 73.5% (95% CI 68.9-77.5%; P=0.02), and 76.1% (95% CI 72.4-79.4%; P=0.02), for No RT, Neo-Adjuvant RT, and Adjuvant RT, respectively. On MVA, Adjuvant RT (HR=0.688; 95% CI, 0.578-0.819; P<0.001) was associated with significantly decreased risk for cancer death. By contrast, Neo-Adjuvant RT was not significantly associated with improved cancer survival (HR=0.863; 95% CI, 0.715-1.043; P=0.127).

CONCLUSION

Adjuvant RT was associated with significantly higher CSS when compared with surgery alone, while the benefit of Neo-Adjuvant RT was not significant. This indicates that surgery followed by Adjuvant RT may still be an important treatment plan for T3N0 rectal cancer with potentially significant survival advantages over other treatment sequences.

National disparities in laparoscopic colorectal procedures for colon cancer

INTRODUCTION

Racial disparity in the treatment of colorectal cancer (CRC) has been cited as a potential cause for differences in mortality. This study compares the rates of laparoscopy according to race, insurance status, geographic location, and hospital size.

METHODS

The 2009 Healthcare Cost and Utilization Project: Nationwide Inpatient Sample (HCUP-NIS) database was queried to identify patients with the diagnosis of CRC by the International Classification of Diseases, Ninth Revision (ICD-9) codes. Multivariate logistic regression was performed to look at age, gender, insurance coverage, academic versus nonacademic affiliated institutions, rural versus urban settings, location, and proportional differences in laparoscopic procedures according to race.

RESULTS

A total of 14,502 patients were identified; 4,691 (32.35 %) underwent laparoscopic colorectal procedures and 9,811 (67.65 %) underwent open procedures. The proportion of laparoscopic procedures did not differ significantly by race: Caucasian 32.4 %, African-American 30.04 %, Hispanic 33.99 %, and Asian-Pacific Islander 35.12 (P = 0.08). Among Caucasian and African-American patients, those covered by private insurers were more likely to undergo laparoscopic procedures compared to other insurance types (P ≤ 0.001). The odds of receiving laparoscopic procedure at teaching hospitals was 1.39 times greater than in nonteaching hospitals (95 % confidence interval [CI] 1.29-1.48) and did not differ across race groups. Patients in urban hospitals demonstrated higher odds of laparoscopic surgery (2.24, 95 % CI 1.96-2.56) than in rural hospitals; this relationship was consistent within races. The odds of undergoing laparoscopic surgeries was lowest in the Midwest region (0.89, 95 % CI 0.81-0.97) but higher in the Southern region (1.14, 95 % CI 1.06-1.22) compared with the other regions.

CONCLUSIONS

Nearly one-third of all CRC surgeries are laparoscopic. Race does not appear to play a significant role in the selection of a laparoscopic CRC operation. However, there are significant differences in the selection of laparoscopy for CRC patients based on insurance status, geographic location, and hospital type.

Predicting chemotherapeutic response and toxicity in colorectal cancer

SUMMARY While treatment for colorectal cancer has evolved significantly over the past 10 years with the introduction of active chemotherapeutic agents and targeted therapies, this has been at the cost of increased toxicity for patients; and significant financial burden for governments and patients. Predicting clinical outcomes, especially given the largely elderly patient population involved, is therefore paramount. This review seeks to summarize existing data regarding the prediction of response and toxicity to chemotherapy agents currently used in the treatment of colorectal cancer.

Association of race and socioeconomic status and outcomes of patients with rectal cancer

BACKGROUND

Few studies have evaluated disparities of race and socioeconomic status (SES) with outcomes in patients with rectal cancer. We hypothesize that disparities exist in the treatment and outcomes among patients with rectal cancer.

METHODS

Medical records of all patients with rectal cancer treated from 2000 to 2009 at an NCI cancer center (Fox Chase Cancer Center) and an urban academic center (Temple University Hospital) were retrospectively reviewed from a prospectively maintained tumor registry database. SES was estimated using census data. Quartiles of income and education based on zip codes were calculated. Lowest vs other quartiles were compared. Clinicopathologic variables included: initial stage, chemotherapy refusal, sphincter preservation, and overall survival (OS).

RESULTS

A total of 748 patients were included in the analysis (581 white, 135 black, 6 other, 26 unknown). No difference in race, SES, or insurance status was seen with regard to stage at presentation. Chemotherapy and radiation refusal was rare. After excluding stage IV patients; sphincter preservation was more common among those with higher income. Median OS for all stages was worse for nonwhite patients (31 vs 50 months, p < .001), and those with low income and education. OS disparities were most pronounced among nonwhite patients with advanced disease. Insurance was not associated with a survival difference. Age, stage, and race were independent predictors of survival.

CONCLUSIONS

Disparity exists in outcomes of patients with rectal cancer. Nonwhite race is associated with worse OS, and lower SES is associated with lower OS and sphincter preservation among patients with rectal cancer.

Racial differences and disparities in cancer care and outcomes: where's the rub?

Despite a profusion of studies over the past several years documenting racial differences in cancer outcomes, there is a paucity of data as to the root causes underlying these observations. This article reviews work to date focusing on black-white differences in cancer outcomes, explores potential mechanisms underlying these differences, and identifies patient, physician, and health care system factors that may account for persistent racial disparities in cancer care. Research strategies to elucidate the relative influence of these various factors and policy recommendations to reduce persistent disparities are also discussed.

Contribution of screening and survival differences to racial disparities in colorectal cancer rates

BACKGROUND

Considerable disparities exist in colorectal cancer (CRC) incidence and mortality rates between blacks and whites in the United States. We estimated how much of these disparities could be explained by differences in CRC screening and stage-specific relative CRC survival.

METHODS

We used the MISCAN-Colon microsimulation model to estimate CRC incidence and mortality rates in blacks, aged 50 years and older, from 1975 to 2007 assuming they had: (i) the same trends in screening rates as whites instead of observed screening rates (incidence and mortality); (ii) the same trends in stage-specific relative CRC survival rates as whites instead of observed (mortality only); and (iii) a combination of both. The racial disparities in CRC incidence and mortality rates attributable to differences in screening and/or stage-specific relative CRC survival were then calculated by comparing rates from these scenarios to the observed black rates.

RESULTS

Differences in screening accounted for 42% of disparity in CRC incidence and 19% of disparity in CRC mortality between blacks and whites. Thirty-six percent of the disparity in CRC mortality could be attributed to differences in stage-specific relative CRC survival. Together screening and survival explained a little more than 50% of the disparity in CRC mortality between blacks and whites.

CONCLUSION

Differences in screening and relative CRC survival are responsible for a considerable proportion of the observed disparities in CRC incidence and mortality rates between blacks and whites.

IMPACT

Enabling blacks to achieve equal access to care as whites could substantially reduce the racial disparities in CRC burden.

Exploring racial differences in outcome and treatment for metastatic colorectal cancer: results from a large prospective observational cohort study (BRiTE)

BACKGROUND

African Americans are more likely to be diagnosed with metastatic colorectal cancer than whites and have shorter survival once they are diagnosed. In this analysis, the authors examined racial differences in clinical outcomes among patients with metastatic colorectal cancer (mCRC) who received bevacizumab.

METHODS

The study cohort consisted of 1589 white patients (81.4%) and 227 African American patients (11.6%) with mCRC who received front-line bevacizumab therapy and who were enrolled in a large, predominantly community-based, prospective, observational cohort study. Differences in time-to-event endpoints and response rates were examined by race. Differences in the incidence of baseline and treatment-related toxicities associated with bevacizumab also were examined. Finally, differences in patterns of care by race were explored.

RESULTS

The median overall survival was 22.6 months for African Americans and 22.9 months for whites, and the median progression-free survival was 9.5 months for African Americans and 9.8 months for whites. Response rates (complete responses plus partial responses) were 37.5% for African Americans and 46.3% for whites (adjusted odds ratio, 0.67; 95% confidence interval, 0.50-0.90). African Americans had higher rates of baseline diabetes (18.9% vs 11%; P = .002), higher rates of hypertension (52.9% vs 41.4%; P = .001), and worsening hypertension while on therapy (13.7% vs 8.9%; P = .02), but no differences in on-treatment arterial thromboembolic events were observed.

CONCLUSIONS

This large observational cohort study of patients with mCRC demonstrated that, when treated in a similar fashion with modern chemotherapy, African Americans and whites had equivalent cancer outcomes. No significant differences in bevacizumab-related toxicity or patterns of care were observed between African Americans and whites. The lower response rate among African Americans deserves further study.

Underuse of surgical resection in black patients with nonmetastatic colorectal cancer: location, location, location

OBJECTIVES

Studies have reported potential underuse of surgical resection in black patients with nonmetastatic colorectal cancer. Our objective was to determine the independent, adverse effect of race on surgical resection, controlling for tumor location, comorbidity, and socioeconomic/insurance status.

METHODS

All cases of nonmetastatic colon/rectal cancer reported to our state's Central Cancer Registry from 1996 to 2002 were identified and linked to Inpatient/Outpatient Surgery Files and the 2000 Census. Comorbidity (Deyo-Charlson Index) was calculated using ICD-9-CM codes and educational level/income were estimated at the zip code level. Characteristics between whites and blacks were compared using [chi]2 tests. Odds ratios (OR) of resection were calculated using logistic regression analysis.

RESULTS

We identified 5590/1932 white and 1906/466 black patients with colon/rectal cancer. Blacks were more likely to be younger, not married, rural, less educated, live in poverty, and uninsured/covered by Medicaid compared with whites (all P < 0.001). Underuse of surgery was far greater among blacks with rectal cancer (82.0% vs. 89.3% in whites, P< 0.001) compared with blacks with colon cancer (92.9% vs. 94.5% in whites, P < 0.001). After controlling for comorbidity/socioeconomic/insurance status and tumor location, the adjusted OR (95% CI) for resection for blacks with colon cancer and blacks with rectal cancer living in poverty were 0.67 (0.51–0.88) and 0.20 (0.07–0.57), respectively.

CONCLUSIONS

Black race is a powerful, independent predictor of underuse of surgery in rectal cancer patients living in poverty. It is incumbent on the gastroenterology/surgical community to determine whether misperceptions about rectal surgery or barriers to successfully navigating multidisciplinary, rectal cancer care may account for these disparities.

Interactions among genes, tumor biology and the environment in cancer health disparities: examining the evidence on a national and global scale

Cancer incidence and mortality rates show great variations across nations and between population groups. These variations are largely explained by differences in age distribution, diet and lifestyle, access to health care, cultural barriers and exposure to carcinogens and pathogens. Cancers caused by infections are significantly more common in developing than developed countries, and they overproportionally affect immigrant populations in the USA and other countries. The global pattern of cancer is not stagnant. Instead, it is dynamic because of fluctuations in the age distribution of populations, improvements in cancer prevention and early detection in affluent countries and rapid changes in diet and lifestyle in parts of the world. For example, increased smoking rates have caused tobacco-induced cancers to rise in various Asian countries, whereas reduced smoking rates have caused these cancers to plateau or even begin to decline in Western Europe and North America. Some population groups experience a disproportionally high cancer burden. In the USA and the Caribbean, cancer incidence and mortality rates are excessively high in populations of African ancestry when compared with other population groups. The causes of this disparity are multifaceted and may include tumor biological and genetic factors and their interaction with the environment. In this review, we will discuss the magnitude and causes of global cancer health disparities and will, with a focus on African-Americans and selected cancer sites, evaluate the evidence that genetic and tumor biological factors contribute to existing cancer incidence and outcome differences among population groups in the USA.

Clinical, laboratory and molecular factors predicting chemotherapy efficacy and toxicity in colorectal cancer

Colorectal cancer (CRC) treatment has evolved significantly over the last ten years with the use of active chemotherapeutic agents including fluoropyrimidines, oxaliplatin and irinotecan plus targeted monoclonal antibodies bevacizumab, cetuximab and panitumumab. The addition of newer chemotherapeutic agents and targeted therapies has improved patient outcomes at the cost of increased toxicity with not all patients benefiting from these treatments. It is necessary for clinicians to more accurately predict clinical outcomes particularly in the predominantly elderly CRC patient population. This review aims to summarise existing data regarding the use of clinical and laboratory variables plus molecular markers in predicting response, survival and toxicity to chemotherapy agents and targeted monoclonal antibodies currently used in the treatment of CRC.

Disparities in colorectal cancer in African-Americans vs Whites: Before and after diagnosis

There are differences between African-American and white patients with colorectal cancer, concerning their characteristics before and after diagnosis. Whites are more likely to adhere to screening guidelines. This is also the case among people with positive family history. Colorectal cancer is more frequent in Blacks. Studies have shown that that since 1985, colon cancer rates have dipped 20% to 25% for Whites, while rates have gone up for African-American men and stayed the same for African-American women. Overall, African-Americans are 38% to 43% more likely to die from colon cancer than are Whites. Furthermore, it seems that there is an African-American predominance in right-sited tumors. African Americans tend to be diagnosed at a later stage, to suffer from better differentiated tumors, and to have worse prognosis when compared with Whites. Moreover, less black patients receive adjuvant chemotherapy for resectable colorectal cancer or radiation therapy for rectal cancer. Caucasians seem to respond better to standard chemotherapy regimens than African-Americans. Concerning toxicity, it appears that patients of African-American descent are more likely to develop 5-FU toxicity than Whites, possibly because of their different dihydropyridine dehydrogenase status. Last but not least, screening surveillance seems to be higher among white than among black long-term colorectal cancer survivors. Socioeconomic and educational status account for most of these differences whereas little evidence exists for a genetic contribution in racial disparity. Understanding the nature of racial differences in colorectal cancer allows tailoring of screening and treatment interventions.

Residual treatment disparities after oncology referral for rectal cancer

BACKGROUND

Black patients with rectal cancer are considerably less likely than white patients to receive adjuvant therapy. We examined the hypothesis that the lower treatment rate for blacks is due to underreferral to medical and radiation oncologists.

METHODS

We used 1992-1999 Surveillance, Epidemiology, and End Results-Medicare data to identify elderly (> or = 66 years of age) patients who had been hospitalized for resection of stage II or III rectal cancer (n = 2716). We used chi(2) tests to examine associations between race and 1) consultation with an oncologist and 2) receipt of adjuvant therapy. We then used logistic regression to analyze the influence of sociodemographic and clinical characteristics (age at diagnosis, sex, marital status, median income and education in area of residence, comorbidity, and cancer stage) on black-white differences in the receipt of adjuvant therapy. All statistical tests were two-sided.

RESULTS

There was no statistically significant difference between the 134 black patients and the 2582 white patients in the frequency of consultation with a medical oncologist (73.1% for blacks vs 74.9% for whites, difference = 1.8%, 95% confidence interval [CI] = > 5.9% to 9.5%, P = .64) or radiation oncologist (56.7% vs 64.8%, difference = 8.1%, 95% CI = > 0.5% to 16.7%, P = .06), but blacks were less likely than whites to consult with both a medical oncologist and a radiation oncologist (49.2% vs 58.8%, difference = 9.6%, 95% CI = 0.9% to 18.2%, P = .03). Among patients who saw an oncologist, black patients were less likely than white patients to receive chemotherapy (54.1% vs 70.2%, difference = 16.1%, 95% CI = 6.0% to 26.2%, P = .006), radiation therapy (73.7% vs 83.4%, difference = 9.7%, 95% CI = 0.4% to 19.8%, P = .06), or both (60.6% vs 76.9%, difference = 16.3%, 95% CI = 4.3% to 28.3%, P = .008). Patient and provider characteristics had minimal influence on the racial disparity in the use of adjuvant therapy.

CONCLUSION

Racial differences in oncologist consultation rates do not explain disparities in the use of adjuvant treatment for rectal cancer. A better understanding of patient preferences, patient-provider interactions, and potential influences on provider decision making is necessary to develop strategies to increase the use of adjuvant treatment for rectal cancer among black patients.

Ethnic disparities in Americans of European descent versus Americans of African descent related to polymorphic ERCC1, ERCC2, XRCC1, and PARP1

Nucleotide excision repair (NER) and base excision repair (BER) pathways are DNA repair pathways that are important in carcinogenesis and in response to DNA-damaging chemotherapy. ERCC1 and ERCC2 are important molecular markers for NER; XRCC1 and PARP1 are important molecular markers for BER. Functional polymorphisms have been described that are associated with altered expression levels of these genes and with altered DNA repair capability. We assayed genomic DNA from 156 Americans of European descent and 164 Americans of African descent for the allelic frequencies of specific polymorphisms of ERCC1 N118N (500C>T), ERCC1 C8092A, ERCC2 K751Q (2282A>C), XRCC1 R399Q (1301G>A), XRCC1 R194W (685C>T), and PARP1 V762A (2446T>C). Differences were observed between Americans of European descent and Americans of African descent in the allelic frequencies of the ERCC1 N118N polymorphism (P < 0.000001). Differences were also observed between these two ethnic groups for ERCC2 K751Q (P = < 0.006675), XRCC1 R399Q (P < 0.000001), and PARP1 V762A (P = 0.000001). The ERCC1 N118N polymorphic variant that is seen most commonly in Americans of European descent is associated with a measurable reduction in NER function. ERCC1-mediated reduction in NER functionality affects the repair of cisplatin-DNA lesions.

Systemic treatment of colorectal cancer

Colorectal cancer is the fourth most common noncutaneous malignancy in the United States and the second most frequent cause of cancer-related death. Over the past 12 years, significant progress has been made in the systemic treatment of this malignant condition. Six new chemotherapeutic agents have been introduced, increasing median overall survival for patients with metastatic colorectal cancer from less than 9 months with no treatment to approximately 24 months. For patients with stage III (lymph node positive) colon cancer, an overall survival benefit for fluorouracil-based chemotherapy has been firmly established, and recent data have shown further efficacy for the inclusion of oxaliplatin in such adjuvant treatment programs. For patients with stage II colon cancer, the use of adjuvant chemotherapy remains controversial, but may be appropriate in a subset of individuals at higher risk for disease recurrence. Ongoing randomized clinical trials are evaluating how best to combine currently available therapies, while smaller studies are evaluating new agents, with the goal of continued progress in prolonging life among patients with metastatic colorectal cancer and increasing cure rates among those with resectable disease.

African-American and Caucasian disparities in colorectal cancer mortality and survival by data source: an epidemiologic review

Over the past four decades in the United States, there has been a divergent trend in mortality rates between African-Americans and Caucasians with colorectal cancer (CRC). Rates among Caucasians have been steadily declining, whereas rates among African-Americans have only started a gradual decline in recent years. We reviewed epidemiologic studies of CRC racial disparities between African-Americans and Caucasians, including studies from SEER and population-based cancer registries, Veterans Affairs (VA) databases, healthcare coverage databases, and university and other medical center data sources. Elevated overall and stage-specific risks of CRC mortality and shorter survival for African-Americans compared with Caucasians were reported across all data sources. The magnitude of racial disparities varied across study groups, with the strongest associations observed in university and non-VA hospital-based medical center studies, while an attenuated discrepancy was found in VA database studies. An advanced stage of disease at the time of diagnosis among African-Americans is a major contributing factor to the racial disparity in survival. Several studies, however, have shown that an increased risk of CRC death among African-Americans remains even after controlling for tumor stage at diagnosis, socioeconomic factors, and co-morbidity. Despite advances in treatment, improvements in the standard of care, and increased screening options, racial differences persist in CRC mortality and survival. Therefore, continued research efforts are necessary to disentangle the clinical, social, biological, and environmental factors that constitute the racial disparity. In addition, results across data sources should be considered when evaluating racial differences in cancer outcomes.

Toxicity profile and efficacy of oral capecitabine as adjuvant chemotherapy for Chinese patients with Stage III colon cancer

PURPOSE

The Xeloda in Adjuvant Cancer Therapy trial, conducted in a white population of patients, established capecitabine (Xeloda) as adjuvant chemotherapy for Stage III colon cancer. Given the ethnical difference in toxicity of adjuvant chemotherapy in colon cancer, this study was designed to evaluate the safety and efficacy of adjuvant capecitabine in Chinese patients with colon cancer.

METHODS

Chinese patients with curatively resected Stage III colon adenocarcinoma, who received adjuvant capecitabine, were entered into a prospective database. Oral capecitabine was given at 1,250 mg/m(2) twice daily, Days 1 to 14, every 21 days, for 8 cycles. Toxicities, laboratory abnormalities, and survival outcomes were evaluated.

RESULTS

Fifty-eight patients were entered into the database between August 2004 and October 2005. The median age was 63.9 years with a male-to-female ratio of 1.15:1. With a median follow-up duration of 20.9 months, 14 patients relapsed and 3 patients died. Disease-free and overall survival at two years was 69 and 97 percent, respectively. Grade 3 toxicities occurred as follows: stomatitis (1.7 percent), diarrhea (0 percent), hand-foot syndrome (41.4 percent), leucopenia (1.7 percent), neutropenia (3.4 percent), and hyperbilirubinemia (1.7 percent). No Grade 4 or 5 toxicity was noted. Compared with the Xeloda in the Adjuvant Cancer Therapy trial, a much higher incidence of serious hand-foot syndrome and a lower rate of severe diarrhea were found in this study.

CONCLUSIONS

A different toxicity profile of adjuvant capecitabine was noted in this study on Chinese patients with colon cancer compared with that reported in the Xeloda in Adjuvant Cancer Therapy trial, whereas the efficacy outcomes were comparable.

Barriers to rehabilitation of colorectal cancer patients

BACKGROUND

Colorectal cancer is one of the most common cancers in the United States. Since 1993 there has been a decrease in colorectal cancer mortality. Thus, there are more cancer survivors. In this manuscript potential barriers encountered during the rehabilitation of the colorectal cancer patient will be discussed.

METHODS

A literature review of manuscripts dealing with the rehabilitation and quality of life of the colorectal cancer patient was performed with specific emphasis on barriers for rehabilitation.

RESULTS

There is not much literature regarding barriers to the rehabilitation of the colorectal cancer patient. The rehabilitation of the colorectal cancer patient is a complex continuum. In order to maximize the potential for rehabilitation a team approach where the patient, family, friends and health care providers participate actively should be undertaken. The most common barriers are in the domains of knowledge, patient, health care system, and therapy. The impact of these barriers will vary from patient to patient.

CONCLUSIONS

There is a paucity of literature regarding barriers to the rehabilitation of the colorectal cancer patient. Prospective databases as well as prospective longitudinal studies need to be established so that the barriers that colorectal cancer patients encounter during their rehabilitation are more clearly identified and understood.

Racial differences in tumor stage and survival for colorectal cancer in an insured population

BACKGROUND

Despite declining death rates from colorectal cancer (CRC), racial disparities have continued to increase. In this study, the authors examined disparities in a racially diverse group of insured patients.

METHODS

This study was conducted among patients who were diagnosed with CRC from 1993 to 1998, when they were enrolled in integrated healthcare systems. Patients were identified from tumor registries and were linked to information in administrative databases. The sample was restricted to non-Hispanic whites (n = 10,585), non-Hispanic blacks (n = 1479), Hispanics (n = 985), and Asians/Pacific Islanders (n = 909). Differences in tumor stage and survival were analyzed by using polytomous and Cox regression models, respectively.

RESULTS

In multivariable regression analyses, blacks were more likely than whites to have distant or unstaged tumors. In Cox models that were adjusted for nonmutable factors, blacks had a higher risk of death from CRC (hazard ratio [HR], 1.17; 95% confidence interval [95% CI], 1.06-1.30). Hispanics had a risk of death similar to whites (HR, 1.04; 95% CI, 0.92-1.18), whereas Asians/Pacific Islanders had a lower risk of death from CRC (HR, 0.89; 95% CI, 0.78-1.02). Adjustment for tumor stage decreased the HR to 1.11 for blacks, and the addition of receipt of surgical therapy to the model decreased the HR further to 1.06. The HR among Hispanics and Asians/Pacific Islanders was stable to adjustment for tumor stage and surgical therapy.

CONCLUSIONS

The relation between race and survival from CRC was complex and appeared to be related to differences in tumor stage and therapy received, even in insured populations. Targeted interventions to improve the use of effective screening and treatment among vulnerable populations may be needed to eliminate disparities in CRC.

Racial disparities in late survival after rectal cancer surgery

BACKGROUND

African-American patients experience higher mortality than Caucasian patients after surgery for most common cancer types. Whether longterm survival after rectal cancer surgery varies by race is less clear.

STUDY DESIGN

Using 1992 to 2003 Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we examined race and longterm survival among African-American and Caucasian rectal cancer patients undergoing resection. We identified racial differences in patient characteristics, structure, and processes of care. We then assessed mortality using a Cox proportional hazards model, sequentially adding variables to explore the extent to which they attenuated the association between race and mortality.

RESULTS

African-American patients had a substantially poorer overall survival rate than Caucasian patients did. Five-year survival rates were 41% and 50%, respectively (p < 0.0001). African Americans were younger (p=0.006), more likely to reside in low income areas (p < 0.0001), and had more baseline comorbid disease (p < 0.0001). They were also more likely to be diagnosed emergently (p < 0.001) and with more advanced cancer (p < 0.001). Accounting for demographic and clinical characteristics reduced the mortality difference, although it remained pronounced (hazard ratio=1.13, CI=1.01 to 1.26). African Americans were more likely to be treated by low volume surgeons and less likely to receive adjuvant therapy (48.6% versus 60.9%, p < 0.0001). After adjusting for provider variables, the hazard ratio for mortality by race was additionally attenuated and became statistically nonsignificant (hazard ratio=1.05, CI=0.92 to 1.20).

CONCLUSIONS

Poorer longterm survival after rectal cancer surgery among African Americans is explained by measurable differences in processes of care and patient characteristics. These data suggest that outcomes disparities could be reduced by strategies targeting earlier diagnosis and increasing adjuvant therapy use among African-American patients.

Colorectal cancer model of health disparities: understanding mortality differences in minority populations

African Americans are more likely to be diagnosed with and die as a result of colorectal cancer than white patients. This review briefly documents these differences and explores the factors that may contribute to advanced stage at diagnosis and reduced survival once African Americans are diagnosed with colorectal cancer. Attention is focused on what is known about the role of socioeconomic status, cancer screening, comorbidities and lifestyle factors, tumor biology and genetics, and the differences in the receipt of and benefit of appropriate therapy. Finally, areas of ongoing and future research and policy initiatives aimed at reducing disparities are discussed.

Prognostic impact of race and ethnicity in the treatment of colorectal cancer

Numerous advances in the treatment of patients who have metastatic disease have improved colorectal cancer management, including new chemotherapeutic agents and combinations and targeted agents that modulate the efficacy of chemotherapy. Recent advances in the administration of irinotecan and oxaliplatin, in combination with 5-FU/LV, plus the addition of targeted agents bevacizumab and cetuximab have afforded steady increases in response rates and survival. Ongoing studies are evaluating the optimal sequencing and combinations of the agents described and the efficacy of new combinations in metastatic and adjuvant settings. Because the number of African-American patients in most clinical trials in colorectal cancer has been low, it is imperative that method increase participation so that new research developments reach all segments of the population.

Colorectal cancer and race: understanding the differences in outcomes between African Americans and whites

Understanding the differences in the incidence and mortality rate between African Americans and whites with CRC remains a perplexing problem. There is clearly not any one factor that explains the observed differences. Clinicians are just beginning to understand the importance of tumor biology, genetics, and lifestyle risk factors in explaining differences in how CRCs present and how they behave. This holds true regardless of a patient's race, sex, or age. Whether these factors will add disproportionately to the understanding of racial differences in presentation and outcome remains to be seen. Certainly, issues surrounding screening for CRC remain important in understanding the advanced stage of presentation for African Americans. In particular, a better understanding is needed of who is being screened and who is not and why. For example, are higher-risk African Americans being screened and if not what are the reasons for this? Importantly, even if one were able to eliminate the differences in stage at presentation between African Americans and whites, a survival disadvantage, albeit a much smaller one, would likely persist. Clearly, there is a need to understand better why African Americans are not receiving recommended therapy at the same rate as whites. This becomes even more important as the life-prolonging options for treating both localized and metastatic colon cancer continue to multiply. Finally, the apparent greater disparity in outcome for African Americans who have stage II disease should be explored in more detail, because this could have an immediate impact on treatment recommendations. For example, a 23-gene signature was recently found to be predictive of recurrence among patients with Dukes B colon cancer [66]. If this model is validated in further studies, one could look at whether African-American patients are more likely to have this predictive signature. The problem has been clearly defined: a higher incidence of and a higher mortality from CRC for African Americans than whites. The task now becomes to continue to understand the reasons for the disparities and ultimately to come up with workable solutions so that the amazing progress in CRC treatment benefits all groups in this country.

Assessment of Infusional 5-Fluorouracil Schedule and Dose Intensity: A Southwest Oncology Group and Eastern Cooperative Oncology Group Study

BACKGROUND

Building on results from Southwest Oncology Group trial 8905, this trial was designed to compare low-dose continuous infusion (LDCI) of 5-fluorouracil (5-FU) versus intermittent high-dose infusion (HDI) of 5-FU in disseminated colorectal cancer (CRC) for evidence of survival advantage based on dose intensity. A companion trial was funded to assess molecular parameters associated with fluoropyrimidine response or resistance and toxicity from these treatments.

PATIENTS AND METHODS

Eligibility included histologic diagnosis of disseminated CRC, measurable or evaluable disease, no previous therapy for metastatic disease, performance status of 0-2, and adequate renal, hepatic, cardiac, and hematologic function. Stratification factors were measurable versus evaluable disease, performance status of 0/1 versus 2, presence versus absence of adjuvant therapy, and presence versus absence of previous surgery and enrollment on the companion trial. Patients were randomized to receive (1) LDCI 5-FU 300 mg/m(2) per day for 28 days every 5 weeks or (2) HDI 5-FU 2,600 mg/m(2) for 24 hours each week.

RESULTS

Between April 1995 and May 1999, 730 patients were accrued (LDCI arm, n = 360; HDI arm, n = 370). Of these, 708 eligible patients were assessable for survival and 690 for toxicity. Median survival for both groups was 13 months. Toxicity was mild; < 10% of patients in both arms had grade > 4 events. There were 8 study-related deaths (1%). Less than 10% of patients were enrolled in the companion trial.

CONCLUSIONS

Increasing 5-FU dose intensity yields no survival advantage beyond that achieved with LDCI 5-FU. This study confirms the favorable toxicity profile of infusional 5-FU. Because no preferential benefit was observed for either infusion schedule, the more convenient weekly schedule should be considered for 5-FU-based combination regimens for disseminated CRC.

Staging of colorectal cancer: past, present, and future

Since the inception of staging for colorectal cancer (CRC), anatomic extent of disease has provided a solid foundation for predicting prognosis and guiding treatment in patients with CRC. However, the rapid advances in biologic and genetic technology have provided many new possibilities for enhancing the predictive power of the staging system. In this article, we will briefly discuss the history of CRC staging, identify the current parameters for American Joint Committee on Cancer staging including recent changes, and offer guidelines for future staging modifications. Although anatomic parameters have served us well for many years, their continued use as sole contributors to CRC staging is questionable. Staging in the future is likely to be a complicated combination of anatomic and biologic markers used together in mathematic modeling to group patients into prognostic risk groups, which can be used to guide tailored therapy.

The impact of socioeconomic status and race on trial participation for older women with breast cancer

BACKGROUND

Older women, and older minorities in particular, are under represented in breast cancer trials. Although socioeconomic status (SES) is associated with both race and age, to the authors' knowledge little is known regarding the impact of SES on trial enrollment among older women with breast cancer.

METHODS

The authors performed a case-control study comparing women who were participants in National Cancer Institute cooperative group breast cancer trials (cases) with a population-based sample of breast cancer patients (controls) obtained from the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare data base. The sample was restricted to women age >/= 65 years who were living in SEER areas. Proxies for SES included the proportion of the population below poverty level (by zip code) and unemployed (by county) as well those with Medicaid insurance coverage. A multivariable logistic regression model was used to test the association of SES with trial participation after accounting for other patient and county characteristics.

RESULTS

In bivariate analysis, trial participants were significantly less likely than community cancer patients to reside in high-poverty zip codes (20.9% vs. 24.9%, respectively; P < 0.001) or to have Medicaid insurance (2.0% vs. 10.0%; P < 0.0001). After adjusting for race, age, and county, trial participation remained inversely related to residing in areas with high poverty (odds ratio [OR] vs. residents of remaining counties, 0.78; 95% confidence interval [95% CI], 0.62-0.98), high unemployment rates (OR vs. residents of residents of counties in the lowest quartile, 0.50; 95% CI, 0.35-0.71), and having Medicaid insurance (OR vs. women without Medicaid, 0.22; 95% CI, 0.13-0.37); black race was not found to be related to trial participation (OR for black vs. white, 1.0; 95% CI, 0.67-1.47).

CONCLUSIONS

Low SES was associated inversely with trial enrollment for older women with breast cancer and appeared to account for the enrollment disparities between black patients and white patients. Future efforts to enhance enrollment of elderly women in cancer research should identify specific barriers related to SES that may be amenable to intervention.

Postsurgical disparity in survival between African Americans and Caucasians with colonic adenocarcinoma

BACKGROUND

Studies of colorectal adenocarcinoma (CRC) indicate a higher mortality rate for African Americans compared with Caucasians in the United States. In the current study, the authors evaluated the racial differences in survival based on tumor location and pathologic stage between African-American patients and Caucasian patients who underwent surgery alone for CRC.

METHODS

All 199 African American patients and 292 randomly selected, non-Hispanic Caucasian patients who underwent surgery between 1981 and 1993 for first primary sporadic CRC at the University of Alabama-Birmingham (Birmingham, AL) or an affiliated Veterans Affairs hospital were assessed for differences in survival. None of these patients received preoperative or postoperative neoadjuvant or adjuvant therapy. Survival curves were generated using the Kaplan-Meier method, and hazard ratios with 95% confidence intervals (95% CI) were estimated from Cox proportional hazards models, adjusting for demographic and tumor characteristics.

RESULTS

African Americans were 1.67 (95% CI, 1.21-2.33) and 1.52 (95% CI, 1.12-2.07) times more likely to die of colonic adenocarcinoma (CAC) within 5 years and 10 years of surgery, respectively, compared with Caucasians. Racial differences in survival were observed among patients with Stage II, III, and IV CAC; however, the strongest and statistically significant association was observed among patients with Stage II CAC. There were no significant racial differences in survival in patients with rectal adenocarcinomas.

CONCLUSIONS

The current findings suggest that the decreased overall survival at 5 years and 10 years postsurgery observed in African-American patients with CAC may not be attributable to tumor stage at diagnosis or treatment but may be due to differences in other biologic or genetic characteristics between African-American patients and Caucasian patients.