Methodological Comparison of Mapping the Expanded Prostate Cancer Index Composite to EuroQoL-5D-3L Using Cross-Sectional and Longitudinal Data: Secondary Analysis of NRG/RTOG 0415.

PURPOSE: To compare the predictive ability of mapping algorithms derived using cross-sectional and longitudinal data. METHODS: This methodological assessment used data from a randomized controlled noninferiority trial of patients with low-risk prostate cancer, conducted by NRG Oncology (ClinicalTrials.gov identifier: NCT00331773), which examined the efficacy of conventional schedule versus hypofractionated radiation therapy (three-dimensional conformal external beam radiation therapy/IMRT). Health-related quality-of-life data were collected using the Expanded Prostate Cancer Index Composite (EPIC), and health utilities were obtained using EuroQOL-5D-3L (EQ-5D) at baseline and 6, 12, 24, and 60 months postintervention. Mapping algorithms were estimated using ordinary least squares regression models through five-fold cross-validation in baseline cross-sectional data and combined longitudinal data from all assessment periods; random effects specifications were also estimated in longitudinal data. Predictive performance was compared using root mean square error. Longitudinal predictive ability of models obtained using baseline data was examined using mean absolute differences in the reported and predicted utilities. RESULTS: A total of 267 (and 199) patients in the estimation sample had complete EQ-5D and EPIC domain (and subdomain) data at baseline and at all subsequent assessments. Ordinary least squares models using combined data showed better predictive ability (lowest root mean square error) in the validation phase for algorithms with EPIC domain/subdomain data alone, whereas models using baseline data outperformed other specifications in the validation phase when patient covariates were also modeled. The mean absolute differences were lower for models using EPIC subdomain data compared with EPIC domain data and generally decreased as the time of assessment increased. CONCLUSION: Overall, mapping algorithms obtained using baseline cross-sectional data showed the best predictive performance. Furthermore, these models demonstrated satisfactory longitudinal predictive ability.

Mapping expanded prostate cancer index composite to EQ5D utilities to inform economic evaluations in prostate cancer: Secondary analysis of NRG/RTOG 0415.

PURPOSE: The Expanded Prostate Cancer Index Composite (EPIC) is the most commonly used patient reported outcome (PRO) tool in prostate cancer (PC) clinical trials, but health utilities associated with the different health states assessed with this tool are unknown, limiting our ability to perform cost-utility analyses. This study aimed to map EPIC tool to EuroQoL-5D-3L (EQ5D) to generate EQ5D health utilities. METHODS AND MATERIALS: This is a secondary analysis of a prospective, randomized non-inferiority clinical trial, conducted between 04/2006 and 12/2009 at cancer centers across the United States, Canada, and Switzerland. Eligible patients included men >18 years with a known diagnosis of low-risk PC. Patient HRQoL data were collected using EPIC and health utilities were obtained using EQ5D. Data were divided into an estimation sample (n = 765, 70%) and a validation sample (n = 327, 30%). The mapping algorithms that capture the relationship between the instruments were estimated using ordinary least squares (OLS), Tobit, and two-part models. Five-fold cross-validation (in-sample) was used to compare the predictive performance of the estimated models. Final models were selected based on root mean square error (RMSE). RESULTS: A total of 565 patients in the estimation sample had complete information on both EPIC and EQ5D questionnaires at baseline. Mean observed EQ5D utility was 0.90±0.13 (range: 0.28-1) with 55% of patients in full health. OLS models outperformed their counterpart Tobit and two-part models for all pre-determined model specifications. The best model fit was: "EQ5D utility = 0.248541 + 0.000748*(Urinary Function) + 0.001134*(Urinary Bother) + 0.000968*(Hormonal Function) + 0.004404*(Hormonal Bother)- 0.376487*(Zubrod) + 0.003562*(Urinary Function*Zubrod)"; RMSE was 0.10462. CONCLUSIONS: This is the first study to identify a comprehensive set of mapping algorithms to generate EQ5D utilities from EPIC domain/ sub-domain scores. The study results will help estimate quality-adjusted life-years in PC economic evaluations.

Tree-based Claims Algorithm for Measuring Pretreatment Quality of Care in Medicare Disabled Hepatitis C Patients.

BACKGROUND: To help broaden the use of machine-learning approaches in health services research, we provide an easy-to-follow framework on the implementation of random forests and apply it to identify quality of care (QC) patterns correlated with treatment receipt among Medicare disabled patients with hepatitis C virus (HCV). METHODS: Using Medicare claims 2006-2009, we identified 1936 patients with 6 months continuous enrollment before HCV diagnosis. We ran a random forest on 14 pretreatment QC indicators, extracted the forest's representative tree, and aggregated its terminal nodes into 4 QC groups predictive of treatment. To explore determinants of differential QC receipt, we compared patient-level and county-level (linked AHRF data) characteristics across QC groups. RESULTS: The strongest predictors of treatment included "liver biopsy," "HCV genotype testing," "specialist visit," "HCV viremia confirmation," and "iron overload testing." High QC [n=360, proportion treated (pt)=33.3%] was defined for patients with at least 2 from the above-mentioned metrics. Good QC patients (n=302, pt=12.3%) had either "HCV genotype testing" or "specialist visit," whereas fair QC (n=282, pt=7.1%) only had "HCV viremia confirmation." Low QC patients (n=992, pt=2.5%) had none of the selected metrics. The algorithm accuracy of predicting treatment was 70% sensitivity and 78% specificity. HIV coinfection, drug abuse, and residence in counties with higher supply of hospitals with immunization and AIDS services correlated with lower QC. CONCLUSIONS: Machine-learning techniques could be useful in exploring patterns of care. Among Medicare disabled HCV patients, the receipt of more QC indicators was associated with higher treatment rates. Future research is needed to assess determinants of differential QC receipt.

Impact of a comprehensive pharmacist medication-therapy management service.

OBJECTIVE: This proof of concept study aimed to determine whether a pharmacist-managed medication therapy management (MTM) program in a private endocrinologist physician's practice reduced healthcare services utilization and related costs 6 months after patients' discharge from an institution with a transition of care service. METHODS: Patients were included in the study if they were English-speaking, ages >18 years, had type 1 or 2 diabetes, and had a recent transition of care experience (inpatient hospital stay or emergency department/urgent care/paramedic or other acute care visit). The study had a non-randomized design where intervention patients, enrolled July 1, 2012-September 30, 2013, were administered MTM at four visits over 6 months and were compared to historical control patients with available electronic medical records from August 8, 2008 to March 15, 2012. The primary study end-point was the rate of 30-day hospital readmissions, as related to the reason for the index admission. Secondary end-points included the cumulative rate of all-cause hospitalizations, emergency department, paramedic and urgent care visits at 30, 60, 90, and 180 days post-discharge as well as imputed total costs, including prescription medication costs, at 180 days. Propensity score weights were constructed to balance covariate characteristics between the intervention and control groups. Weighted multivariate negative binomial and generalized linear regressions were used to model cumulative utilization rates and log-transformed costs, respectively. RESULTS: The intervention (n = 28) and control (n = 73) groups had 0% hospital readmissions at 30 days post-discharge. In propensity score weighted multivariate analyses, cumulative utilization rate was not different between the two groups (IRR = 1.61, p = 0.72 at 180 days) while costs in the intervention group were lower but not statistically different (cost ratio = 0.65, p = 0.13 at 180 days). CONCLUSIONS: Further studies should investigate whether the integration of pharmacists in transition of care models could reduce readmission and healthcare utilization rates post-discharge.

Multispecialist Care and Mortality in Hepatocellular Carcinoma.

PURPOSE: Multidisciplinary physician care has increased for many cancers yet little evidence exists for hepatocellular carcinoma (HCC). The purpose of this study was to explore the association between multispecialist care and mortality in HCC. METHODS: Treated patients with an HCC primary diagnosis from 2000 to 2007 were studied using Surveillance, Epidemiology, and End Results-Medicare data. A surrogate variable for multidisciplinary care was defined-multispecialist care-as the number of disciplines among surgeons, radiology oncologist, intervention radiologist, hematologist/medical oncologist, gastroenterologist, and generalist in the pretreatment period. Multivariate survival analysis was conducted and adjusted for selection and survival bias. RESULTS: Of 3588 treated HCC patients, 1434 (40%) saw 1, 1343 (37%) saw 2, and 811 (23%) saw 3 or more specialists. Patients with multispecialist care received treatment that differed from patients who saw a single specialist. In propensity score-adjusted survival analysis, patients who saw 3 or more specialist types were associated with 10% (P=0.04) reduced mortality, compared with those who saw 1 specialist. When stratified by treatment received, patients on chemotherapy who saw 3 or more specialist types were associated with 28% (P=0.002) reduced mortality, compared with those who saw 1 specialist. CONCLUSIONS: Multispecialist care for treated HCC patients was associated with reduced mortality, particularly among chemotherapy recipients. While adjusting for selection and survival bias, our study is limited in capturing a causal relationship between coordinated multidisciplinary care and mortality. Our findings may provide support for the development of coordinated care delivery models but should be confirmed through more rigorous examination in future studies.

Cardiovascular event-free survival after adjuvant radiation therapy in breast cancer patients stratified by cardiovascular risk.

The objective of this study was to estimate the risk of a cardiovascular event or death associated with modern radiation in a population of elderly female breast cancer patients with varying baseline cardiovascular risk. The data used for this analysis are from the linked Surveillance, Epidemiology, and End-Results (SEER)-Medicare database. The retrospective cohort study included women aged 66 years and older with stage 0-III breast cancer diagnosed between 2000 and 2005. Women were grouped as low, intermediate, or high cardiovascular risk based on the presence of certain clinical diagnoses. The risk for the combined outcome of a hospitalization for a cardiovascular event or death within 6 months and 24 months of diagnosis was estimated using a multivariable Cox model. The median follow-up time was 24 months. Among the 91,612 women with American Joint Committee on Cancer (AJCC) stage 0-III breast cancer: 39,555 (43.2%) were treated with radiation therapy and 52,057 (56.8%) were not. The receipt of radiation therapy in the first 6 months was associated with a statistically significant increased risk for the combined outcome in women categorized as high risk (HR = 1.510; 95% CI, 1.396-1.634) or intermediate risk (HR = 1.415; 95% CI, 1.188-1.686) but not low risk (HR = 1.027; 95% CI, 0.798-1.321). Women with a prior medical history of cardiovascular disease treated with radiation therapy are at increased risk for an event and should be monitored for at least 6 months following treatment with radiation therapy.

Diabetes control through an educational intervention.

OBJECTIVE: We evaluated the effect of an educational intervention administered to patients or/and physicians on the reduction in HbA(1c) and achieving diabetic control in a high-risk primarily Black inner-city population. METHODS: The study was designed as a four-arm randomized clinical trial where an educational program on diabetes was offered to physicians only, patients only, and both physicians and their patients, while the fourth arm did not receive any instruction. We built regression models at 24 months of follow-up to assess the likelihood of reaching glycemic goal as well as to measure the absolute reduction in HbA(1c) controlling for arm assignment, insulin use, race, age, sex, smoking, insulin use, and having achieved blood pressure control. RESULTS: Between April 2005 and July 2007, there were 823 patients randomized into the study. In multivariate analyses, the intervention group in which only patients received education showed a trend toward achieving a significant mean reduction in HbA(1c) with 49% (P = .06) higher odds of reaching glycemic control and .12 (P = .06) greater absolute percentage point drop in HbA(1c) compared to the no education group. CONCLUSION: Although our study reports positive results, it warrants a special emphasis on the behavior of the patient. Study results bring attention to disease management programs such as peer support networks that empower the patients that shift some of the responsibility to them.

Comparative and cost effectiveness of treatment modalities for hepatocellular carcinoma in SEER-Medicare.

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) is increasing in the USA and worldwide. Several treatments are available for patients diagnosed at any disease stage. It remains unclear how medical expenditures vary across patients who remain untreated or undergo different modes of therapy. We evaluate the comparative and cost effectiveness of treatment modalities for HCC from a Medicare perspective. METHODS: The Surveillance, Epidemiology, and End Results (SEER) registries and linked Medicare database with claims from Parts A/B were used to identify Medicare enrollees with initial diagnosis of HCC between 2000 and 2007 and followed through 2009. Patients were assigned to treatment modalities based on HCC staging systems: transplant, resection, liver directed, radiation, chemotherapy or no treatment. Survival benefits and cumulative Medicare expenditures were estimated in multivariate models, stratified by initial disease stage, to control for confounding. Cost-effectiveness ratios compared costs and benefits of the modalities across initial stages. RESULTS: Cancer stages I, II, III, IV and unstaged represented 24, 9, 14, 17 and 37 % of 11,047 patients, respectively. Fewer than 40 % received any treatment. Relative to no treatment, transplant was most effective in reducing mortality, followed by resection, liver directed, and radiation or chemotherapy. Resection tended to be most cost effective in early staged and unstaged patients; transplant was least cost effective. In stage IV patients, liver directed therapy was more cost effective than chemotherapy or radiation. CONCLUSIONS: Survival benefit was attributable to all treatment modalities. More effective treatments incurred greater Medicare expenditures, but resection patients incurred the least expenditures per year of life gained.

Transarterial chemoembolization treatment: association between multiple treatments, cumulative expenditures, and survival.

OBJECTIVES: To examine cumulative survival and Medicaid-paid expenses associated with multiple courses of transarterial chemoembolization (TACE) as primary treatment for hepatocellular carcinoma (HCC). METHODS: Medicare enrollees diagnosed with primary HCC from 2000 to 2007, ever treated with TACE, but not transplant/resection, followed through 2009 by using the Surveillance, Epidemiology and End-Results Program and linked Medicare databases. Cumulative all-cause/HCC-related survival was estimated by using multivariate Cox proportional hazards models stratified by the total number of TACE treatments. Multivariate weighted Cox regressions estimated the average risk of mortality faced with nonproportional hazards. Lin's inverse probability-weighted least squares regression method estimated cumulative Medicare expenditures adjusted for censoring and covariates. RESULTS: Of 1228 patients, 34% were stage 1, 16% stage 2, 19% stage 3, 6% stage 4, and 26% unstaged. About 44% were aged 65 to 75 years, 69% were men, and 72% were Caucasian. Over half (57%) of the patients received one course, 24% two, 11% three, and 8% four courses of TACE. One-course patients incurred an average $74,788 (95% confidence interval [CI] $71,890-$77,686), two-course patients $101,126 (95% CI $94,395-$107,856), three-course patients $111,776 (95% CI $101,931-$121,621), and four-plus-course patients $148,878 (95% CI $136,346-$161,409). One-course patients lived (all-cause) an average 1.86 (95% CI 1.82-1.90), two-course patients 2.09 (95% CI 2.05-2.13), three-course patients 2.81 (95% CI 2.66-2.97), and four-plus-course patients 3.06 (95% CI 2.95-3.18) years after diagnosis. Average risk of all-cause mortality was not significantly different between one/two courses or three/four-plus courses. CONCLUSIONS: Cumulative Medicare expenditures nearly doubled from one-course to four-plus-course patients. On average, four-plus-course patients lived over one more year than did one-course patients. Physician/patient decisions should be balanced with consideration of efficient use of limited resources, but payer's intervention in physician discretion may not be important in this setting.

Social networks help control hypertension.

Cardiovascular health disparities continue to pose a major public health problem. The authors evaluated the effect of education administered within social networks on the improvement of hypertension in 248 African Americans compared with historical controls. Patients formed clusters with peers and attended monthly hypertension education sessions. The authors assessed the likelihood of reaching goal below predefined systolic blood pressure (SBP) and diastolic blood pressure (DBP) thresholds as well as the absolute reduction in SBP and DBP, controlling for diabetes, smoking, baseline hypertension, and demographics. The intervention group was more likely to have ever reached treatment goal at 12-month follow-up (odds ratio, 1.72; P=.11). At 18-month follow-up, the Maryland Cardiovascular Disease Promotion Program group had a statistically significant larger drop in SBP (-4.82 mm Hg, P<.0001) and DBP (-3.37 mm Hg, P=.01) than the control group. The clustering of patients in social networks around hypertension education has a positive impact on the management of hypertension in minority populations and may help address cardiovascular health disparities.

Social networks in cardiovascular disease management.

Cardiovascular disease remains the leading cause of death in the USA. Social networks have a positive association with obesity, smoking cessation and weight loss. This article summarizes studies evaluating the impact of social networks on the management of cardiovascular disease. The 35 studies included in the article describe the impact of social networks on a decreased incidence of cardiovascular disease, depression and mortality. In addition, having a large-sized social network is also associated with better outcomes and improved health. The role of pharmacists is beginning to play an important role in the patient-centered medical home, which needs to be incorporated into social networks. The patient-centered medical home can serve as an adaptive source for social network evolvement.

Clinical evaluation of natalizumab for formulary consideration.

IMPORTANCE OF THE FIELD: Natalizumab is a monotherapy for relapsing forms of multiple sclerosis (MS) and maintaining remission in Crohn's disease (CD). Evaluation of natalizumab's clinical relevance must be performed before considering its place in treatment of these diseases. AREAS COVERED IN THIS REVIEW: MEDLINE and PubMed searches were performed using the keywords multiple sclerosis, Crohn's disease, natalizumab and clinical trials. The manufacturer's product information was consulted to extract additional data. Pivotal clinical trials included: Natalizumab Safety and Efficacy in Relapsing Remitting Multiple Sclerosis (AFFIRM), Safety and Efficacy of Natalizumab in Combination With Interferon Beta-1a in Patients With Relapsing Remitting Multiple Sclerosis (SENTINEL), Efficacy of Natalizumab as Active Crohn's Therapy (ENACT)-1 and 2 and Efficacy of Natalizumab in Crohn's Disease Response and Remission (ENCORE). WHAT THE READER WILL GAIN: AFFIRM and SENTINEL showed improvements in progression of MS. ENACT-1 failed to show a significant effect, but the follow-up trials ENACT-2 and ENCORE were able to demonstrate a response to natalizumab. TAKE HOME MESSAGE: Two trials on efficacy of Tysabri for treatment of MS demonstrated positive results. Efficacy for CD was mixed. More research demonstrating head-to-head evidence against other agents is necessary to determine if Tysabri's benefits are significant.

Economic implications of comorbid conditions among Medicaid beneficiaries with COPD.

OBJECTIVES: To characterize a comprehensive comorbidity profile and to explore the economic implications of comorbidity among patients with chronic obstructive pulmonary disease (COPD). METHODS: This retrospective cohort study analyzed medical claims from the Maryland Medicaid database. We employed a 1:2 case-control design to select COPD patients (n=1388) and demographically matched controls (n=2776) aged 40 to 64 years with 24 months of continuous enrollment. Odds ratios were employed to compare comorbidity differences, including 17 conditions defined by the Charlson Comorbidity Index (CCI) and 6 additional conditions commonly observed in COPD patients. We estimated the incremental medical utilization and medical cost by specific condition. RESULTS: Compared with the controls, Medicaid COPD patients had higher comorbidity burden and were more likely to have myocardial infarction, congestive heart failure, cerebrovascular disease, peptic ulcer, mild liver disease, hypertension, sleep apnea, tobacco use, and edema. COPD patients on average had 24% more medical claims (81.4 vs. 65.4, p<0.001) and were 33% more expensive than controls ($7603 vs. $5732, p<0.001). Ten conditions defined by the CCI as well as hypertension, tobacco use, and edema were associated with incremental medical utilization and cost in COPD patients; depression was associated with incremental medical utilization but not cost. CONCLUSIONS: The high burden of comorbidity in COPD patients translates into additional medical utilization and cost. Effective disease management and treatment protocols are needed to reduce comorbidity burden. The development of a COPD-specific comorbidity measure may be used to identify high-risk subgroups and to predict utilization and cost.

The cost effectiveness and budget impact of natalizumab for formulary inclusion.

BACKGROUND: Crohn's disease (CD) and multiple sclerosis (MS) are debilitating autoimmune diseases, which represent a substantial cost burden in the context of managed care. As a corollary, there is an unmet pharmacotherapeutic need in patient populations with relapsing forms of MS, in addition to populations with moderately to severely active CD with evidence of inflammation who have experienced an inadequate response to other mainstream therapies. The purpose of this study was to analyze the clinical and economic data associated with natalizumab (Tysabri) and to determine the potential impact of its formulary inclusion in a hypothetical health plan. FINDINGS: Regarding MS, the implemented cost-effectiveness and budget-impact models demonstrated an anticipated reduction in relapse rate of 67% over 2 years, and a total therapy cost of $72,120 over 2 years, equating to a cost per relapse avoided of $56,594. With respect to the model assumptions, the market share of natalizumab would experience an increase to 8.5%, resulting in a total per-member, per-month healthcare cost increase of $0.003 ($0.002 for pharmacy costs and $0.001 for medical costs). Regarding CD, over a 2-year period outlined by the model, natalizumab produced the highest average time in remission, steroid-free remission, and remission or response in comparison to the other agents. The mean total costs associated with the initiation of natalizumab, infliximab, and adalimumab were $68,372, $62,090, and $61,796, respectively. Although natalizumab's costs were higher, the mean time spent in remission while on this medication was 4.5 months, as opposed to 2.4 months for infliximab and 2.9 months with adalimumab. This shift in market share was used to estimate the change in total costs (medical + pharmacy), and the per-member per-month change for the model's base case was calculated to be $0.035. LIMITATIONS: The aforementioned cost-effectiveness results for natalizumab in the treatment for CD and MS were limited by the model's predetermined assumptions. These assumptions include anticipated reduction in relapse rate after 2 years of therapy and acquisition costs in the MS model, as well as assuming a certain percentage of patients were primary and secondary failures of TNFalpha inhibitor therapy in the CD model. CONCLUSION: The evidence presented here demonstrates that natalizumab provides clinical practitioners with another tool in their fight against both MS and CD, albeit by way of a different mechanism of action. After a thorough review of the evidence, the authors find that natalizumab has been shown to be relatively cost effective in the treatment of both conditions from a payer perspective; the therapy adds a new option for those patients for whom conventional treatment was unsuccessful.

A perspective on African American participation in clinical trials.

The relatively low participation of African Americans in phase III clinical trials has raised concerns about the appropriateness of generalizing study results to African American populations. If African American enrollment in clinical trials continues to be low, the society may continue to see disparities in the treatment of diseases as well as unanswered questions as to why the population fares less than others when diagnosed with certain diseases such as cancer and diabetes. Additionally, more clinical trials are needed to explicitly monitor the difference in outcomes across different populations. This article discusses the various reasons why African American patient recruitment and participation is sub-optimal; the critical role of clinical trials in therapies; recommendations by important authorities; and a new practice model (Collaborative Care Model) as an innovative strategy to augment participation rates of African Americans [and other minorities] in clinical trials.

Diabetic retinopathy.

The prognosis of some of the most prevalent conditions seems to be intricately related to myriad risk factors, largely modifiable, but often leading to irreversible complications when left unmanaged. This study exemplifies the multidisciplinary approach necessary, to successfully control diabetic retinopathy, one of the leading complications of diabetes, and to discuss promising therapies. Based on a Medline Ovid database search, we present a clinical and economic review of the evidence on the epidemiology and risk factors of diabetic retinopathy, its prognosis and economic implications. Among adults aged 20-74, diabetic retinopathy (DR) is the most frequent cause of blindness. However, in both types 1 and 2 DM, improved glycemic control reduces the development and progression of DR. Risk factors of DR include duration of diabetes, pregnancy, renal disease, age, smoking, alcohol, hyperlipidemia and antioxidants. A number of drugs may play a role in DR therapy in the coming few years; eg, somatostatin agonists (sandostatin), corticosteroids (triamcinolone, dexamethasone, fluocinolone), vascular endothelial growth factor inhibitors (pegaptanib, ranibizumab), hyaluronidase and plasmin enzyme. Whether these therapies have a clinically significant impact on DR progression however, remains to be seen.

Compliance with medicine.

Compliance with medication regimens is critical in assessing the effectiveness of treatments. As new drugs are approved for marketing and prescribed to diverse patient populations, the FDA now recommends further observational studies to continuously monitor unforeseen side effects or efficacy. More research is needed to develop valid and reliable tools to assess adherence of patients to treatment recommendations and adherence of patients to treatment guidelines, when applicable. Information on adherence is a relevant to physicians and their patients as it is to insurers and payers, who need to implement cost-effective disease management programs. This review also has highlighted examples in the adherence literature specific to glaucoma medications and based on longitudinal survival analyses of claims data. Such results may be best complemented by primary, survey-based data collected from patients in observational studies.

Disparities in prevalence rates for lung, colorectal, breast, and prostate cancers in Medicaid.

BACKGROUND: Given previous reports of variations in prevalence of cancer in low-income individuals, we sought to determine if disparities in cancer prevalence existed in a similarly-insured Medicaid population. METHODS: Using Maryland Medicaid administrative claims data, prevalence rates of lung, colorectal, breast, and prostate cancers were calculated for Maryland Medicaid recipients who were continuously eligible during the period from January 1, 2000 to December 31, 2000. Chi-squared tests were used to test the differences across subgroups. Cancer prevalence data were age-adjusted using Maryland Medicaid enrollees as the standard population. RESULTS: The care prevalence rates for lung, colorectal, breast, and prostate cancers were 75/10,000, 63/10,000, 92/10,000, and 45/10,000, respectively. These rates were 1.2 to 5.2 times those reported at the national level. Generally, higher cancer prevalence rates in certain racial groups in Maryland Medicaid were consistent with previous studies. Regional differences in cancer prevalence existed for each cancer studied. CONCLUSIONS: Limiting our study sample to a population of uniformly low socioeconomic individuals did not eliminate the disparity in prevalence rates between blacks and whites. Different patterns of racial disparity across regions reported by previous researchers might be due to small area variation in addition to socioeconomic status.