Economic studies in colorectal cancer: challenges in measuring and comparing costs

Estimates of the costs associated with cancer care are essential both for assessing burden of disease at the population level and for conducting economic evaluations of interventions to prevent, detect, or treat cancer. Comparisons of cancer costs between health systems and across countries can improve understanding of the economic consequences of different health-care policies and programs. We conducted a structured review of the published literature on colorectal cancer (CRC) costs, including direct medical, direct nonmedical (ie, patient and caregiver time, travel), and productivity losses. We used MEDLINE to identify English language articles published between 2000 and 2010 and found 55 studies. The majority were conducted in the United States (52.7%), followed by France (12.7%), Canada (10.9%), the United Kingdom (9.1%), and other countries (9.1%). Almost 90% of studies estimated direct medical costs, but few studies estimated patient or caregiver time costs or productivity losses associated with CRC. Within a country, we found significant heterogeneity across the studies in populations examined, health-care delivery settings, methods for identifying incident and prevalent patients, types of medical services included, and analyses. Consequently, findings from studies with seemingly the same objective (eg, costs of chemotherapy in year following CRC diagnosis) are difficult to compare. Across countries, aggregate and patient-level estimates vary in so many respects that they are almost impossible to compare. Our findings suggest that valid cost comparisons should be based on studies with explicit standardization of populations, services, measures of costs, and methods with the goal of comparability within or between health systems or countries. Expected increases in CRC prevalence and costs in the future highlight the importance of such studies for informing health-care policy and program planning.

The management of adenocarcinoma of the prostate in rural Georgia: A population-based analysis

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Background: The management of adenocarcinoma of the prostate (ACP) in minority populations and in the rural setting remains understudied. We conducted a population-based analysis exploring the management of ACP in rural Georgia. Methods: All cases of ACP diagnosed from 2001 to 2003 in a rural, 33-county, Southwest Georgia region were included. Data were obtained for all patients through direct medical record abstraction. Patient characteristics were described and associated with three specific outcomes: receipt of therapy, initiation of planned therapy, and completion of radiation therapy (RT) when initiated. Results: One thousand eighty seven patients were available for the analysis; median patient age was 69, and 44% of the patients were African American (AA). A total of 804 patients underwent a course of definitive therapy or elected to pursue regular active surveillance (AS). Of the patients 8.9% underwent radical prostatectomy (RP) alone, 3.1% RP and external beam radiation therapy (EBRT), 30.2 % EBRT alone, 10.8% brachytherapy (BT) alone, and 44.5% combination EBRT and BT; 2.5 % of patients underwent AS. Hormone therapy (HT) was used in 43.8% of all patients available for analysis. In a multivariable analysis conducted for the entire patient cohort, not being married (OR 0.60, 95% CI 0.42-0.85, p=0.004), lack of insurance (OR 0.32, 95% CI 0.16-0.61, p=0.008), and older age (OR 0.93, 95% CI 0.91-0.95, p<0.001) were all independently associated with not receiving definitive therapy. Race was not significantly related to receipt of definitive therapy. The full course of EBRT was successfully completed as planned in 98.4% of patients. Conclusions: Amongst those patients undergoing therapy for ACP in rural Georgia, a combination of BT and EBRT was the most common treatment modality. In contrast to recent studies, we found that race was not a significant predictor of receipt of care in Southwest Georgia. In this rural setting, EBRT was associated with extremely high rates of treatment completion. Despite the geographic and socioeconomic challenges associated with rural residency, our population-based study demonstrates that EBRT is a common treatment modality, with high patient compliance, even when used in a rural setting.

Prostate cancer screening in men ages 75 and older fell by 8 percentage points after Task Force recommendation

In 2008 the US Preventive Services Task Force recommended against screening men ages 75 and older for prostate cancer. Using Medicare Current Beneficiary Survey Access to Care files and linked claims, we compared trends in prostate-specific antigen (PSA) testing rates between men ages 75 and older and men ages 65-74. We estimate that the revised recommendation led to a 7.9-percentage-point decline in annual PSA testing rates over two years among men ages 75 and older. Although 42 percent of men in this age group continue to receive PSA tests, our results highlight the potential of guidelines with negative recommendations to reduce the use of low-value medical care.

Chemoradiation therapy sequencing for resected pancreatic adenocarcinoma in the National Cancer Data Base

BACKGROUND

Pancreatic adenocarcinoma (PAC) has low overall survival (OS) rates and high recurrence rates following surgical resection. The role for preoperative radiation therapy (prRT) for PAC versus postoperative RT (poRT) remains uncertain. The authors used the National Cancer Data Base (NCDB) to report prRT outcomes for the largest multi-institutional patient cohort to date.

METHODS

NCDB data were obtained for all patients who underwent resection and external beam radiation (RT) for PAC from 1998 to 2002. Patients with metastatic (M1) disease, intraoperative RT, RT both before and after surgery, missing OS, or missing RT variables were excluded. Univariate (UV) and multivariate (MV) analysis were run using treatment characteristics, tumor characteristics, and patient demographics. The difference in patients' known characteristics was described by a chi-square test or analysis of variance.

RESULTS

A total of 5414 patients were identified. Of these, 277 received prRT and 5137 received poRT. Overall, 92.9% received chemotherapy and 7.1% received RT alone; 56% (2990 of 5307) of patients had stage III disease, according to American Joint Commission on Cancer (AJCC) staging manual, 5th edition. Median tumor size was 3 cm (range: 0-9.9 cm); 82% (199 of 244) of patients with prRT had negative surgical margins; 72% (3383 of 4699) of patients with poRT had negative margins. Forty-one percent (71 of 173) of patients with prRT were lymph node (LN)-positive; 65% (3159 of 4833) of patients with poRT were LN-positive. Median OS for patients with prRT was 18 months (95% CI = 18-19 months) and for patients with poRT, 19 months (95% CI = 17-22 months).

CONCLUSIONS

Receipt of prRT was associated with lower stage, higher rates of negative margins, and lower rates of lymph node positivity at resection. However, there was no significant difference in median OS versus that of the poRT group.

The potential and peril of health insurance tobacco surcharge programs: evidence from Georgia's State Employees' Health Benefit Plan

INTRODUCTION

A rapidly growing number of U.S. employers are charging health insurance surcharges for tobacco use to their employees. Despite their potential to price-discriminate, little systematic empirical evidence of the impacts of these tobacco surcharges has been published. We attempted to assess the impact of a health insurance surcharge for tobacco use on cessation among enrollees in Georgia's State Health Benefit Plan (GSHBP).

METHODS

We identified a group of enrollees in GSHBP who began paying the tobacco surcharge at the program's inception in July 2005. We examined the proportion of these enrollees who certified themselves and their family members as tobacco-free and no longer paid the surcharge through April 2011, and we defined this as implied cessation. We compared this proportion to a national expected annual 2.6% cessation rate. We also compared our observation group to a comparison group to assess surcharge avoidance.

RESULTS

By April 2011, 45% of enrollees who paid a tobacco surcharge starting in July 2005 had certified themselves as tobacco-free. This proportion exceeded the expected cessation based on 3 times the national rate (p < .001). The length of enrollment was not statistically different between our observation and comparison groups (p = .427).

CONCLUSIONS

The reported rates of tobacco cessation among GSHBP enrollees resulting from a tobacco surcharge substantially exceed national rates. These surcharges appear to be effective, but the value of these results, and the effectiveness of health insurance surcharges in changing behavior, are tempered by the important limitation that enrollees' certification of quitting was self-reported and not subject to additional, clinical verification.

Augmenting state cancer registry data for quality-of-care assessment: A Georgia-based application to evaluate receipt of adjuvant therapies for breast cancer and colorectal cancer

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Background: The value of linking population-based cancer registry data with insurance claims files to assess quality of care has been demonstrated in numerous studies, including those using NCI’s linked SEER-Medicare database, covering patients age 65+ in fee-for-service plans, and studies linking registry data with Medicaid, private insurance, or managed care data covering the under-65 population. We describe a prototype program linking registry data with multiple data sources to assess quality of care for at-risk populations in a defined geographical area. Methods: Data exchange agreements were executed among the investigative site (Emory University), Georgia state government, and the claims data sources/vendors. We linked Georgia Cancer Registry (GCR) records for 1999-2005 incident cases of breast and colorectal cancer with enrollment and medical services records from Medicare, Medicaid, Kaiser Permanente of Georgia, and the State Health Benefit Plan (SHBP) which covers all state workers and dependents. Following data quality checks, algorithms based on National Quality Forum (NQF) endorsed breast and colorectal cancer quality measures were applied to each linked data set to assess performance. Results: The linked data sets included 60% of all breast and colorectal cancer cases in the GCR over the study period. Quality measure performance rates varied notably across payers. For example, the percent of Stage III colon cancer patients meeting the NQF standard for adjuvant chemotherapy in the linked GCR-Medicaid, GCR-Kaiser, and GCR-SHBP data were, respectively, 75%, 92%, and 92% (p<0.05). The rates for breast cancer patients meeting standards for adjuvant chemotherapy were 86%, 84%, and 87% (p=NS), respectively. Patients in the linked GCR-Medicare data (all age 65+) generally had lower performance rates for each NQF measure. Conclusions: Linking state cancer registry data with multiple public and private sources of administrative data is technically feasible, and may represent a viable strategy for building a national cancer data system for quality improvement, as recommended in 1999 by the Institute of Medicine.

Determinants of the combined use of external beam radiotherapy and brachytherapy for low-risk, clinically localized prostate cancer

BACKGROUND

Prostate cancer treatment choices have been shown to vary by physician and patient characteristics. For patients with low-risk, clinically localized prostate cancer, the authors examined the impact of their clinical, sociodemographic, and radiation oncologists' (RO) characteristics on the likelihood that the patients would receive combined external beam radiotherapy and brachytherapy, a treatment regimen that is at variance with clinical guidelines.

METHODS

The Surveillance, Epidemiology and End Results (SEER)-Medicare linked database and the American Medical Association Physician Masterfile were used in a retrospective analysis of 5531 patients with low-risk, clinically localized prostate cancer who were diagnosed between 2004 and 2007, and the 708 ROs who treated them. Hierarchical logistic regression analyses were used to evaluate the relationship between patient and RO characteristics and the use of combined therapy within 6 months of diagnosis.

RESULTS

Overall, 356 patients (6.4%) received combined therapy. Nonclinical factors were found to be associated with combined therapy. After adjusting for patient and RO characteristics, the odds of receiving combined therapy for patients residing in Georgia were found to be significantly greater than for all other SEER regions. Black patients were significantly less likely to receive combined therapy (odds ratio, 0.62; 95% confidence interval, 0.40-0.96 [P= .03]) compared with white patients. In addition, ROs accounted for 36.6% of the variation in patients receiving combined therapy.

CONCLUSIONS

Geographic and sociodemographic factors were found to be significantly associated with guideline-discordant combined therapy for patients diagnosed with low-risk, clinically localized prostate cancer. Which RO a patient consults is important in determining whether they receive combined therapy.

Screening for diabetes and prediabetes should be cost-saving in patients at high risk

OBJECTIVE

Although screening for diabetes and prediabetes is recommended, it is not clear how best or whom to screen. We therefore compared the economics of screening according to baseline risk.

RESEARCH DESIGN AND METHODS

Five screening tests were performed in 1,573 adults without known diabetes--random plasma/capillary glucose, plasma/capillary glucose 1 h after 50-g oral glucose (any time, without previous fast, plasma glucose 1 h after a 50-g oral glucose challenge [GCTpl]/capillary glucose 1 h after a 50-g oral glucose challenge [GCTcap]), and A1C--and a definitive 75-g oral glucose tolerance test. Costs of screening included the following: costs of testing (screen plus oral glucose tolerance test, if screen is positive); costs for false-negative results; and costs of treatment of true-positive results with metformin, all over the course of 3 years. We compared costs for no screening, screening everyone for diabetes or high-risk prediabetes, and screening those with risk factors based on age, BMI, blood pressure, waist circumference, lipids, or family history of diabetes.

RESULTS

Compared with no screening, cost-savings would be obtained largely from screening those at higher risk, including those with BMI >35 kg/m(2), systolic blood pressure ≥130 mmHg, or age >55 years, with differences of up to -46% of health system costs for screening for diabetes and -21% for screening for dysglycemia110, respectively (all P < 0.01). GCTpl would be the least expensive screening test for most high-risk groups for this population over the course of 3 years.

CONCLUSIONS

From a health economics perspective, screening for diabetes and high-risk prediabetes should target patients at higher risk, particularly those with BMI >35 kg/m(2), systolic blood pressure ≥130 mmHg, or age >55 years, for whom screening can be most cost-saving. GCTpl is generally the least expensive test in high-risk groups and should be considered for routine use as an opportunistic screen in these groups.

Regional, provider, and economic factors associated with the choice of active surveillance in the treatment of men with localized prostate cancer

Data on initial treatment of 8232 cases of localized prostate cancer diagnosed in 2004 were obtained by medical record abstraction (including hospital and outpatient locations) from seven state cancer registries participating in the Centers for Disease Control and Prevention's Breast and Prostate Cancer Data Quality and Patterns of Care Study. Distinction was made between men receiving no therapy with no monitoring plan (no therapy/no plan [NT/NP]) and those receiving active surveillance (AS). Overall, 8.6% received NT/NP and 4.7% received AS. Older age at diagnosis, lower clinical risk group, and certain registry locations were significant predictors of use of both AS and NT/NP. AS was also related to having more severe comorbidities, whereas nonwhite race was predicted receiving NT/NP. Men receiving AS lived in areas with a higher number of urologists per 100 000 men than those receiving NT/NP. In summary, physician and clinical factors were stronger predictors of AS, whereas demographic and regional factors were related to receiving NT/NP. Physicians appear reluctant to recommend AS for younger patients with no comorbidities.

Examining racial differences in diffuse large B-cell lymphoma presentation and survival

We performed a retrospective cohort analysis of 701 (533 white and 144 black) patients with diffuse large B-cell lymphoma (DLBCL) treated at two referral centers in southern United States between 1981 and 2010. Median age of diagnosis for blacks was 50 years vs. 57 years for whites (p < 0.001). A greater percentage of blacks presented with elevated lactate dehydrogenase levels, B-symptoms and performance status ≥ 2. More whites (8%) than blacks (3%) had a positive family history of lymphoma (p = 0.048). There were no racial differences in the use of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone; 52% black vs. 47% white, p = 0.73). While black race predicted worse survival among patients treated with CHOP (hazard ratio [HR] 1.8, p < 0.001), treatment with R-CHOP was associated with improved survival irrespective of race (HR 0.61, p = 0.01). Future studies should examine biological differences that may underlie the observed racial differences in presentation and outcome.

Impact of adjuvant radiotherapy on survival after pancreatic cancer resection: an appraisal of data from the national cancer data base

PURPOSE

The impact of adjuvant radiotherapy for pancreatic adenocarcinoma (PAC) remains controversial. We examined effects of adjuvant therapy on overall survival (OS) in PAC, using the National Cancer Data Base (NCDB).

METHODS

Patients with resected PAC from 1998 to 2002 were queried from the NCDB. Factors associated with receipt of adjuvant chemotherapy (ChemoOnly) versus adjuvant chemoradiotherapy (ChemoRad) versus no adjuvant treatment (NoAdjuvant) were assessed. Cox proportional hazard modeling was used to examine effect of adjuvant therapy type on OS. Propensity scores (PS) were developed for each treatment arm and used to produce matched samples for analysis to minimize selection bias.

RESULTS

From 1998 to 2002, a total of 11,526 patients underwent resection of PAC. Of these, 1,029 (8.9 %) received ChemoOnly, 5,292 (45.9 %) received ChemoRad, and 5,205 (45.2 %) received NoAdjuvant. On univariate analysis, factors associated with improved OS included: younger age, higher income, higher facility volume, lower tumor stage and grade, negative margins and nodes, and absence of adjuvant therapy. On multivariate analysis with matched PS, factors independently associated with improved OS included: younger age, higher income, higher facility volume, later year of diagnosis, smaller tumor size, lower tumor stage, and negative tumor margins and nodes. ChemoRad had the best OS (hazard ratio 0.70, 95 % confidence interval 0.61-0.80) in a PS matched comparison with ChemoOnly (hazard ratio 1.04, 95 % confidence interval 0.93-1.18) and NoAdjuvant (index).

CONCLUSIONS

Adjuvant chemotherapy with radiotherapy is associated with improved OS after PAC resection in a large population from the NCDB. On the basis of these analyses, radiotherapy should be a part of adjuvant therapy for PAC.

Factors impacting decision by African American and underserved populations to choose active surveillance in early-stage prostate cancer

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Background: African-American (AA) men have the highest rates of prostate cancer (PCa) incidence and mortality in the U.S. Screening for PCa with prostate specific antigen (PSA) has allowed detection of early stage disease, but side effects of radical prostatectomy and radiation raise concerns about unfavorable risk:benefit ratios of PSA screening and subsequent therapy. Active surveillance (AS) is an option for early-stage PCa (ESPC), but only 10% of men eligible for AS choose this approach. The 2011 NIH State-of-the-Science Conference promoted the need to enhance decision-making (DM) about AS. In 2012, the U.S. Preventive Services Task Force recommended against PSA screening, while encouraging patient DM. Our study examined DM needs by men (N=204; 68% AA; screening PSA within normal limits) and their significant others (SO) (N=181; 65% AA) regarding AS and other ESPC options. Methods: This multi-center, mixed methods study (N=402; 51% rural) included 5 sites nationwide. Subjects completed quantitative questionnaires prior to focus groups (FG); 54 FG were held, with separate groups for men and SO. Results: After adjusting for education, comorbidities, insurance, age, health literacy, distance to treatment center, willingness to travel, income and numeracy score, AA men were significantly more likely to be influenced by convenience (OR: 2.84, 95% CI: 1.42-5.65) compared to Caucasians. Rural residence, however, did not affect DM. In qualitative analysis, numerous themes were identified relevant to choice of AS: physician treatment discussions being limited to their own specialty; confusion due to conflicting sources of information; convenience; worry about untreated cancer remaining and treatment toxicities; and lack of awareness of AS as an option. SO tended to value cure over avoiding side effects. Conclusions: While the impact of new PCa screening guidelines is uncertain, for AS to become a viable treatment option, providers will need to discuss along with other therapeutic alternatives. SO are influential in DM and may be less enthusiastic about AS than men. For AA men, AS may be a particularly attractive option given the relative influence of convenience in DM.

Augmenting state cancer registry data for quality-of-care assessment: A Georgia-based application to evaluate receipt of adjuvant therapies for breast cancer and colorectal cancer

6523

Background: The value of linking population-based cancer registry data with insurance claims files to assess quality of care has been demonstrated in numerous studies, including those using NCI’s linked SEER-Medicare database, covering patients age 65+ in fee-for-service plans, and studies linking registry data with Medicaid, private insurance, or managed care data covering the under-65 population. We describe a prototype program linking registry data with multiple data sources to assess quality of care for at-risk populations in a defined geographical area. Methods: Data exchange agreements were executed among the investigative site (Emory University), Georgia state government, and the claims data sources/vendors. We linked Georgia Cancer Registry (GCR) records for 1999-2005 incident cases of breast and colorectal cancer with enrollment and medical services records from Medicare, Medicaid, Kaiser Permanente of Georgia, and the State Health Benefit Plan (SHBP) which covers all state workers and dependents. Following data quality checks, algorithms based on National Quality Forum (NQF) endorsed breast and colorectal cancer quality measures were applied to each linked data set to assess performance. Results: The linked data sets included 60% of all breast and colorectal cancer cases in the GCR over the study period. Quality measure performance rates varied notably across payers. For example, the percent of Stage III colon cancer patients meeting the NQF standard for adjuvant chemotherapy in the linked GCR-Medicaid, GCR-Kaiser, and GCR-SHBP data were, respectively, 75%, 92%, and 92% (p<0.05). The rates for breast cancer patients meeting standards for adjuvant chemotherapy were 86%, 84%, and 87% (p=NS), respectively. Patients in the linked GCR-Medicare data (all age 65+) generally had lower performance rates for each NQF measure. Conclusions: Linking state cancer registry data with multiple public and private sources of administrative data is technically feasible, and may represent a viable strategy for building a national cancer data system for quality improvement, as recommended in 1999 by the Institute of Medicine.

Role of the urologist in whether locoregional prostate cancer patients consult with a radiation oncologist

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Background: Multiple treatment options exist for prostate cancer patients, and therapeutic recommendations may differ depending on characteristics of the specialist consulted. The clinical judgment of specialists can play a critical role in the initial treatment choice, especially in cases where there is no professional consensus regarding the optimal treatment strategy. We examined the association between prostate cancer patients’ urologists’ practice affiliation with medical schools on the likelihood the patient would consult a radiation oncologist. Methods: Using the Surveillance, Epidemiology and End Results – Medicare linked database and the American Medical Association Physician Masterfile, we conducted a retrospective cohort study of 39,915 patients aged 66 years or older who were diagnosed between 2004 - 2007 with locoregional prostate cancer, and the 2,404 urologists who performed the diagnostic biopsies. Multilevel regression analysis was used to evaluate the influence of patients’ urologists’ practice affiliations with medical schools on the patients’ consultation with a radiation oncologist within 9 months of diagnosis. Results: Overall, 25,110 (62.9%) patients consulted with a radiation oncologist. After adjusting for patient, tumor and urologist characteristics, patients who saw urologists practicing within non-institutional settings were significantly more likely to consult with a radiation oncologist (odds ratio [OR], 1.19; 95% confidence interval [95% CI], 1.05-1.34, p = 0.006) when compared to those who saw urologists practicing within settings with a major medical school affiliation. In addition, patients who saw urologists ≥ 58 years old were significantly more likely to consult with a radiation oncologist (OR, 1.71; 95% CI, 1.16-2.50, p = 0.006) when compared to those who saw urologists < 43 years old. Conclusions: Locoregional prostate cancer patients who received their diagnostic biopsy by urologists practicing in non-institutional settings and those who saw older urologists were significantly more likely to eventually consult with a radiation oncologist. This may have implications on which patient eventually receives radiation as initial therapy.

Predictors of care for early-stage breast cancer in Appalachia

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Background: We studied care for early-stage breast cancer in Appalachia, a region with health infrastructure, socioeconomic (SES) and geographic disparities. Methods: Cases of stage I-III breast cancer diagnosed 2006-2008 were identified from cancer registries of KY, NC, OH, and PA and linked to Medicare data. Guideline concordance was studied in eligible groups, as follows: endocrine therapy for hormone receptor positive cancer (n=1429); and radiation (RT) use after breast conserving surgery (BCS) divided into two groups - age 70 years and older with ER/PR+, <2 cm, node negative tumors where it may have been acceptable to forgo RT (OptRT, n=1108) and all other cases (IndRT, n=1422). Multivariate (MV) and univariate analyses were performed. Covariates included age, state, Appalachian Regional Commission (ARC) economic status, Commission of Cancer (CoC) status, state, access to care, number of beds, surgery facility ownership, volume, and chemotherapy/radiation offered, provider graduation year and volume, Charlson comorbidity, diagnosis year, Medicaid/Medicare dual status, histology, tumor size, tumor sequence, positive lymph nodes, ER/PR status, stage, herceptin use, and BCS/mastectomy indicator. Results: Mean age was 74 years and 97% were white. Guideline-concordance was 76% for endocrine therapy, 83% for IndRT, and 77% for OptRT. Younger age predicted higher concordance in all groups. Endocrine therapy use was lower in NC vs PA (OR 0.60; 95% CI 0.41-0.88) and greater for cases whose provider graduated in years 1984-1988, vs. 1989+ (1.55; 1.06-2.29). In IndRT, provider volume in the 3rdquartile vs. highest quartile predicted increased radiation use (2.36; 1.46-3.81). In OptRT, less receipt of radiation was predicted by residence in NC vs. PA (0.26; 0.18-0.48), and competitive ARC class vs. transitional (0.60; 0.36-0.99). Conclusions: Within Appalachia, there are SES and provider characteristics that are associated with use of guideline concordant care.

Influence of guideline-concordant adjuvant therapy on all-cause and disease-specific survival among breast cancer patients in rural Georgia

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Background: This study examines whether receipt of chemo-, radiation, and hormonal therapy regimens that are jointly guideline concordant improve survival outcomes among women diagnosed with breast cancer in a rural region of the United States. Methods: All women identified by the state cancer registry residing in rural southwest Georgia diagnosed with early stage breast cancer during 2001-2003 were included. Medical chart abstraction and registry data were used to determine treatment concordance with the 2000 NIH consensus development conference guidelines on breast cancer treatment. Patients were Concordant versus Non-Concordant according to whether their receipt (or non-receipt) of each adjuvant therapy type was according to guidelines. To examine the effects of concordance on all-cause and breast cancer-specific survival, Cox models were developed that used both propensity score weighting and 2-stage residual inclusion instrumental variable techniques to adjust for patient selection effects. Results: In all-cause analyses, Concordance versus Non-Concordance was associated with significantly better survival (hazard ratios (HRs) 0.41 (95% CI: 0.24-0.72) to 0.54 (95% CI: 0.33-0.87). Similar findings emerged in breast cancer-specific survival analyses, with HRs significantly less than 1.0 in most cases. Diagnosis at older age or later disease stage strongly predicted poorer survival outcome; being not married was significant in all-cause but not breast cancer-specific models. Survival was not generally associated with surgical treatment delay, insurance status, socioeconomic status, rural/urban status, comorbidities, tumor grade, or hormonal status. HR for black women versus white was greater than 1.0 across models but never significant (p=0.05). Conclusions: Breast cancer patients in rural Georgia who received guideline-concordant adjuvant therapy had significantly better all-cause and breast cancer-specific survival, based on Cox model analyses that attempted to control for multiple clinical and demographic factors, as well as selection effects. These findings extend the evidence that guideline bundles of care improve outcomes.

Determinants of the combined use of external beam radiation therapy and brachytherapy for low-risk localized prostate cancer

e16039

Background: Prostate cancer treatment patterns have been shown to vary by physician and patient characteristics. For low-risk localized prostate cancer patients, we examined the association between their region of residence and their radiation oncologists’ practice affiliations with medical schools on the likelihood they would receive both external beam radiation therapy (EBRT) and brachytherapy (BT) – a treatment regimen that is at variance with clinical guidelines and has not been shown to improve survival or other patient centered outcomes. Methods: Using the Surveillance, Epidemiology and End Results – Medicare linked database and the American Medical Association Physician Masterfile, we conducted a retrospective cohort study of 4,479 patients aged 66 years or older who were diagnosed between 2004-2007 with low-risk localized prostate cancer, and the 401 radiation oncologists who saw them. Multilevel regression analyses were used to evaluate the influence of patients’ region of residence and radiation oncologists’ practice affiliations with medical schools on the combined use of EBRT and BT on patients within 6 months of diagnosis. Results: Overall, 231 (5.2%) patients received combined EBRT and BT. After adjusting for patient, tumor and radiation oncologist characteristics, patients who saw radiation oncologists with no practice affiliation with medical schools were significantly more likely to receive combined EBRT and BT (odds ratio [OR], 3.14; 95% confidence interval [95% CI], 1.50-6.59, p = 0.003). Regional variations were also observed; the odds of receiving combined therapy for patients residing in California (OR, 0.1; 95% CI, 0.03-0.33, p<0.0001) were significantly less than those in Georgia (OR, 1.0; referent). Conclusions: Low-risk localized prostate cancer patients residing in Georgia were significantly more likely to receive combined EBRT and BT when compared to those in other SEER Regions. Radiation oncologists without practice affiliations with medical schools were significantly more likely to treat patients with combined therapy; such treatment patterns are not consistent with clinical guidelines and unlikely to have significant survival benefit.

The influence of adjuvant radiotherapy dose on overall survival in patients with resected pancreatic adenocarcinoma

BACKGROUND

Adjuvant radiotherapy (A-RT) for patients with resected pancreatic adenocarcinoma (PAC) is controversial. In the current study, the authors aim to determine whether there is an association between overall survival (OS) and A-RT dose.

METHODS

National Cancer Data Base (NCDB) data were obtained for all patients who received A-RT for resected PAC from 1998 through 2002. Univariate and multivariate survival analyses were performed along with Kaplan-Meier estimates for A-RT levels < 40 grays (Gy), 40 Gy to < 50 Gy, 50 Gy to < 55 Gy, and ≥ 55 Gy.

RESULTS

A total of 1385 patients met the inclusion criteria. The median age of the patients was 64 years (range, 29 years-87 years). All patients underwent surgical resection and A-RT with or without chemotherapy. A total of 231 patients were diagnosed with stage I disease, 273 were diagnosed with stage II disease, 734 were diagnosed with stage III disease, and 126 were diagnosed with stage IVA disease (according to the fifth edition of the American Joint Committee on Cancer); 21 were found to have an unknown stage of disease. The median A-RT dose was 45 Gy (range, 1.63 Gy-69 Gy). The median OS was 21 months (95% confidence interval [95% CI], 19 months-23 months). On multivariate analysis, an A-RT dose < 40 Gy (hazards ratio [HR], 1.30 [95% CI, 1.03-1.66]; P = .031), an A-RT dose of 40 Gy to < 50 Gy (HR, 1.17 [95% CI, 1.00-1.37]; P = .05), and an A-RT dose ≥ 55 Gy (HR, 1.44 [95% CI, 1.08-1.93]; P = .013) predicted worse OS compared with the reference category of 50 Gy to < 55 Gy.

CONCLUSIONS

A-RT doses of < 40 Gy, 40 Gy to < 50 Gy, and ≥ 55 Gy were found to be associated with an inferior OS. The dose of A-RT delivered appears to influence OS and a prospective study evaluating the addition of optimally delivered A-RT for patients with resected PAC is needed.