Information on radiation treatment in patients with breast cancer: the advantages of the linked medicare and SEER data. Surveillance, Epidemiology and End Results

Capturing Chemotherapy and Radiotherapy Dose Among Breast Cancer Patients With the Utah All-Payer Claims Database Compared With Gold-Standard Abstraction

OBJECTIVE

To evaluate the validity of the Utah statewide All-Payer Claims Database (APCD), we compared breast cancer-specific treatments and dosages with gold-standard abstraction of medical records.

STUDY DESIGN

In this pilot study, breast cancer treatments were abstracted by a certified tumor registrar at the Utah Cancer Registry (UCR) for patients diagnosed in 2013 with breast cancer. The abstraction of medical records was the gold standard for comparison with treatments identified in the APCD. The reliability and agreement between the treatment identified in the APCD and abstraction data were measured with sensitivity and specificity. Dose consistency was measured with the intraclass correlation coefficients (ICC).

RESULTS

Compared with the 186 abstractions, the sensitivity of the APCD to identify chemotherapy agents was high: 89% for any agent, 91% for carboplatin, 83% for docetaxel, 82% for doxorubicin, or 94.7% for biologic therapy. The consistency between the chemotherapy dosage identified in the claims and the abstraction varied from 63% to 76%. For radiotherapy, the sensitivity of the claims to identify the completed radiotherapy regimen was 66%. The ICC between radiotherapy doses identified in the claims and the abstraction was 54% (95% confidence interval [CI], 48%, 67%).

CONCLUSIONS

Employing these novel methods, the claims were highly reliable in identifying cancer treatment agents overall, namely carboplatin, docetaxel, and trastuzumab. The claims were of moderate utility in capturing the treatment dose information. In addition to the APCD, the use of multiple data sources improved the completeness of cancer treatment information.

Consistency Between State's Cancer Registry and All-Payer Claims Database in Documented Radiation Therapy Among Patients Who Received Breast Conservative Surgery

PURPOSE

Arkansas is one of only four known states that have linked All-Payer Claims Database (APCD) to state's cancer registry (Arkansas Cancer Registry [ACR]). We evaluated the reporting consistency of radiation therapy (RT) between the two sources.

METHODS

Women age ≥ 18 years diagnosed in 2013-2017 with early-stage hormone receptor-positive breast cancer who received breast-conserving surgery were identified. Patients must have continuous insurance coverage (any private plans, Medicaid, and Medicare) in the 13 months (month of diagnosis and 12 months after). Receipt of RT was identified independently from ACR and APCD. We calculated sensitivity, specificity, positive predictive value, and negative predictive value for receipt of RT coded by the registry compared with APCD billing claims as the gold standard. We assessed the degree of concordance between the data sources by Cohen's kappa statistics.

RESULTS

The final sample included 2,695 patients who were in both databases and satisfied our inclusion/exclusion criteria. Using APCD as the gold standard, there were high sensitivity (88.1%) and positive predictive value (87.7%) and moderate specificity (71.1%) and negative predictive value (71.8%). The overall agreement between the two sources was 83.0%, with a kappa statistic of 0.59 (95% CI, 0.56 to 0.63). Consistency measures varied by age, stage, and insurance type with Medicare fee-for-service coverage only having the best and private insurance only the worse consistency.

CONCLUSION

In patients with early-stage hormone receptor-positive breast cancer who received breast-conserving surgery, recording of RT receipt was moderately consistent between Arkansas APCD and ACR. Future studies are needed to identify factors affecting reporting consistency to better use this unique resource in addressing population health problems.

Radiation Records in the National Cancer Database: Variations in Coding and/or Practice Can Significantly Alter Survival Results

PURPOSE

The aim of the current work was to quantify internally inconsistent and anomalous radiation therapy (RT) data in the National Cancer Database (NCDB) and determine their association with overall survival (OS) using node-positive uterine cancer as a test clinical scenario.

MATERIALS AND METHODS

We identified all NCDB participants with International Federation of Gynecology and Obstetrics stage IIIC1 to IIIC2 uterine cancer treated with hysterectomy and adjuvant RT between 1998 and 2012. Variables that were reviewed to identify anomalous data included RT site, modality, dose, fractions, timing, duration, and stage. We used χ² testing to associate anomalous data with reporting facility and demographic variables. OS was estimated using the Kaplan-Meier method and comparison between cohorts was performed using the log-rank test. Univariable and multivariable Cox proportional hazards regression analyses were performed.

RESULTS

Of the 14,298 analyzed participants, 2,288 (16.0%) had one or more anomalous data entry, 538 (3.8%) likely because of an incomplete RT course. χ² testing suggested differences in anomalous data prevalence by reporting facility type (P = .0007), geographic region (P < .001), distance from participants' homes (P < .001), diagnosis year (P < .001), and location of RT relative to reporting facility (P = .0038). Five-year OS in those with one or more anomalous data entry was 51.3% versus 58.0% for those without anomalous data (P < .001), and anomalous data remained significantly associated with OS on multivariable analysis. After excluding insufficient, excessive, or unknown total RT dose, anomalous data were no longer significant on multivariable analysis.

CONCLUSION

The overwhelming majority of RT data within the NCDB seem to be appropriate for the clinical scenario. Nevertheless, approximately one eighth of participants in this test clinical scenario had adjuvant RT data that were internally inconsistent or outside generously defined norms. The presence of anomalous RT data was significantly associated with compromised OS, an effect not observed after correcting for total RT dose.

Validity of state cancer registry treatment information for adolescent and young adult women

BACKGROUND

Population-based cancer registries collect information on first course of treatment that may be utilized in research on cancer care quality, yet few studies have investigated the validity of this information. We examined the accuracy and completeness of registry-based treatment information in a cohort of adolescent and young adult women.

METHODS

Women diagnosed with breast cancer, lymphoma, thyroid cancer, cervical/uterine cancer or ovarian cancer at ages 15-39 during 2003-2014 were identified using data from the North Carolina Central Cancer Registry (CCR) (N = 2342). CCR data were linked to Medicaid and private insurance claims data, and claims were reviewed for the 12 months following diagnosis to identify cancer treatments received. Using claims data as the gold standard, we calculated the sensitivity and positive predictive value (PPV) of CCR data for receipt of chemotherapy, radiation and hormone therapy. We also compared dates of treatment initiation between the two data sources.

RESULTS

For all cancer types combined, the sensitivity of the CCR data was high for chemotherapy (86%) and moderate for radiation (74%). PPVs were 82% and 83% for chemotherapy and radiation, respectively. Both the sensitivity (67%) and PPV (70%) were lower for hormone therapy for breast cancer. For all three treatment types, dates of initiation in the registry and the claims differed by ≤30 days for most women.

CONCLUSIONS

In this cohort of young women, population-based cancer registry data on chemotherapy receipt was reasonably accurate and complete in comparison with insurance claims. Radiation and hormone therapy appeared to be less complete.

Investigating confounders of the association between survival and adjuvant radiation therapy after breast conserving surgery in a sample of elderly breast Cancer patients in Appalachia

Background

To explain the association between adjuvant radiation therapy after breast conserving surgery (BCS RT) and overall survival (OS) by quantifying bias due to confounding in a sample of elderly breast cancer beneficiaries in a multi-state region of Appalachia.

Methods

We used Medicare claims linked registry data for fee-for-service beneficiaries with AJCC stage I-III, treated with BCS, and diagnosed from 2006 to 2008 in Appalachian counties of Kentucky, Ohio, North Carolina, and Pennsylvania. Confounders of BCS RT included age, rurality, regional SES, access to radiation facilities, marital status, Charlson comorbidity, Medicaid dual status, institutionalization, tumor characteristics, and surgical facility characteristics. Adjusted percent change in expected survival by BCS RT was examined using Accelerated Failure Time (AFT) models. Confounding bias was assessed by comparing effects between adjusted and partially adjusted associations using a fully specified structural model.

Results

The final sample had 2675 beneficiaries with mean age of 75, with 81% 5-year survival from diagnosis. Unadjusted percentage increase in expected survival was 2.75 times greater in the RT group vs. non-RT group, with 5-year survival of 85% vs 60%; fully adjusted percentage increase was 1.70 times greater, with 5-year rates of 83% vs 71%. Quantification of incremental confounding showed age accounted for 71% of the effect reduction, followed by tumor features (12%), comorbidity (10%), dual status(10%), and institutionalization (8%). Adjusting for age and tumor features only resulted in only 4% bias from fully adjusted percent change (70% change vs 66%).

Conclusion

Quantification of confounding aids in determining covariates to adjust for and in interpreting raw associations. Substantial confounding was present (60% of total association), with age accounting for the largest share (71%); adjusting for age plus tumor features corrected for most of the confounding (4% bias). The direct effect of BCS RT on OS accounted for 40% of the total association.

Racial differences in long-term adjuvant endocrine therapy adherence and mortality among Medicaid-insured breast cancer patients in Texas: Findings from TCR-Medicaid linked data

BACKGROUND

There are racial/ethnic disparities in breast cancer mortality may be attributed to differences in receipt of adjuvant cancer treatment. Our purpose was to determine whether the mortality disparities could be explained by racial/ethnic differences in long-term adherence to adjuvant endocrine therapy (AET).

METHODS

We conducted a retrospective cohort study with the Texas Cancer Registry and Medicaid claims-linked dataset of women (20-64 years) diagnosed with local and regional breast cancer who filled a prescription for AET from 2000-2008. Adherence to AET was measured at three time points (1-, 3-, and 5-year adherence) using a value for the percentage of medication filled for each period divided by the total number of possible prescriptions prescribed (Medication Possession Ratio, MPR). We created a binary variable of adherence (MPR≥80%). We performed multivariable logistic regressions to assess racial differences for the odds of AET adherence and Cox proportional hazard models to determine the risk of mortality adjusting for potential confounding variables of SES, comorbidities, tumor prognostic factors, and other cancer treatment.

RESULTS

Of the 1,497 women with breast cancer who initiated AET, 56.9%, 42.3%, and 33.3% were adherent for 1, 3, and 5-years, respectively. Hispanics compared to non-Hispanic whites did differ in the proportion that were adherent to 5-years of AET. In the adjusted analysis for long-term adherence to AET, Hispanics did not have a significantly increased risk of death compared to non-Hispanic white patients (HR: 1.13, 95% CI: 0.58-2.21). However, black compared to non-Hispanic white patients had significantly lower odds of three-year adherence (OR: 0.45, 95% CI: 0.28-0.73). After controlling for 5-year adherence to AET, the risk of death for black compared to non-Hispanic white patients was 12% lower (HR: 1.90; 95% CI: 1.03-3.51) and in the fully adjusted model, the disparity was reduced and no longer significant (OR: 1.86, 95% CI: 0.94-3.66).

CONCLUSIONS

Long-term adherence in the Medicaid population is suboptimal and racial/ethnic differences in AET adherence may partially explain disparities in mortality. This study underscores the critical need to ensure long-term adherence to AET for all racial/ethnic groups to decrease disparities in mortality.

Racial and geographic disparities in adherence and discontinuation to adjuvant endocrine therapy in Texas Medicaid-insured patients with breast cancer

The purpose of the study is to examine disparities in AET adherence and discontinuation among Texas Medicaid-insured early-stage breast cancer patients. Texas Cancer Registry Medicaid-linked database was used from 2000 to 2007 for breast cancer patients aged 20-64. Multivariable logistic regression was performed to test the association of race/ethnicity and geographic factors with AET adherence and discontinuation. Of the 1240 women with breast cancer, 60.8% of non-Hispanic white vs 46.6% of Black patients were adherent to AET in the first year. After adjusting for confounding, Black patients had lower odds of adherence compared to non-Hispanic white patients (Odds ratio 0.62, 95% CI 0.44-0.87), but they were not more likely to discontinue therapy during the study period. Patients from the Texas/Mexico border had higher odds of adherence compared to other regions (OR 2.32, 95% CI 1.29-4.18). There are substantial racial and geographic disparities in AET adherence and discontinuation among Texas Medicaid-insured women.

Propensity scores with misclassified treatment assignment: a likelihood-based adjustment

Propensity score methods are widely used in comparative effectiveness research using claims data. In this context, the inaccuracy of procedural or billing codes in claims data frequently misclassifies patients into treatment groups, that is, the treatment assignment ($T$) is often measured with error. In the context of a validation data where treatment assignment is accurate, we show that misclassification of treatment assignment can impact three distinct stages of a propensity score analysis: (i) propensity score estimation; (ii) propensity score implementation; and (iii) outcome analysis conducted conditional on the estimated propensity score and its implementation. We examine how the error in $T$ impacts each stage in the context of three common propensity score implementations: subclassification, matching, and inverse probability of treatment weighting (IPTW). Using validation data, we propose a two-step likelihood-based approach which fully adjusts for treatment misclassification bias under subclassification. This approach relies on two common measurement error-assumptions; non-differential measurement error and transportability of the measurement error model. We use simulation studies to assess the performance of the adjustment under subclassification, and also investigate the method's performance under matching or IPTW. We apply the methods to Medicare Part A hospital claims data to estimate the effect of resection versus biopsy on 1-year mortality among $10\,284$ Medicare beneficiaries diagnosed with brain tumors. The ICD9 billing codes from Medicare Part A inaccurately reflect surgical treatment, but SEER-Medicare validation data are available with more accurate information.

Effect of photodynamic therapy combined with Celecoxib on expression of cyclooxygenase-2 protein in HeLa cells

The present study assessed the effect of photodynamic therapy (PDT) combined with Celecoxib (Cel) on cervical cancer HeLa cells. An MTT assay was performed to detect the inhibitory effects of Cel with different concentrations (10, 50, 100, 150, 200, 250 and 300 µg/ml) on the proliferation of HeLa cells. Subsequently, HeLa cells were divided into control group (group H), 50 g/ml Celecoxib group (group C), PDT group (group P), 50 g/ml Cel + PDT group (group P + C) and western blotting and immunohistochemistry were performed to detect the expression of cyclooxygenase-2 (COX-2) protein in the different groups. Cel inhibited HeLa cells proliferation 24 h following administration, among which 200 µg/ml induced a 50% inhibition rate; the relative expression level of COX-2 protein in group P + C was significantly decreased compared with that in either group C or group P (P<0.05). Cel inhibited the proliferation of human cervical cancer cells in a concentration-dependent manner, and combined PDT therapy may improve treatment outcomes.

Risk of adverse events associated with front-line anti-myeloma treatment in Medicare patients with multiple myeloma

This study aims to examine the risks of adverse events associated with anti-multiple myeloma (MM) therapies in a large population-based cohort of elderly patients with MM. Patients diagnosed with advanced MM from 2005 through 2009 and receiving anti-MM therapy were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked data. We compared safety outcomes between novel agents (proteasome inhibitor (PI) and immunomodulatory drugs (IMiD)) and other therapies and between PI- or IMiD-based regimens and PI plus IMiD combination regimens. Of 2587 patients with advanced MM, 2048 (79%) received novel agents and 539 (21%) received other therapies. Patients with preexisting anemia and thrombocytopenia were significantly more likely to receive novel agents (85.9 vs. 82.4%, P = 0.038; 13.8 vs. 10.4%, P = 0.036), while those with preexisting cardiovascular disease and hypertension were significantly less likely to receive novel agents (73.4 vs. 79.8%, P = 0.003; 81.3 vs. 85.2%, P = 0.035). The hazard ratios for anemia, peripheral neuropathy, and thromboembolic events for patients receiving novel agents compared with those receiving other therapies were 1.19 (95% CI, 1.06-1.32), 1.57 (95% CI, 1.15-2.15), and 1.31 (95% CI, 1.03-1.67). The hazard ratios for anemia, neutropenia, and thromboembolic events for patients receiving PI plus IMiD combination therapies compared with those receiving PI- or IMiD-based therapies were 1.31 (95% CI, 1.12-1.54), 1.66 (95% CI, 1.27-2.18, and 1.37 (95% CI, 1.02-1.86). Novel agents significantly increased the risk of anemia, peripheral neuropathy, and thromboembolic events. PI plus IMiD combination therapies were associated with significantly higher risk for anemia, neutropenia, and thromboembolic events.

Health Care Disparities in Cancer Patients Receiving Radiation: Changes in Insurance Status After Medicaid Expansion Under the Affordable Care Act

PURPOSE

To compare insurance status in cancer patients receiving radiation before and after Medicaid expansion under the Patient Protection and Affordable Care Act (ACA), in both expanded and non-expanded states.

METHODS AND MATERIALS

Newly diagnosed cancer patients aged 18 to 64 years who received radiation from 2011 to 2014 were compiled from the Surveillance, Epidemiology, and End Results database. Patients with a prior cancer diagnosis or unknown insurance status were excluded. Insurance rates at diagnosis were examined before (2011-2013) and after Medicaid expansion (2014) and compared between states that fully or did not fully expand Medicaid.

RESULTS

A total of 197,290 patients were analyzed. Of these, 73% lived in expanded states. After expansion, there was a 53% relative decrease in uninsured rates in expanded states (4.3%-2.1%) and a 5% relative decrease in non-expanded states (8.4%-8.0%) (P < .0001). In expanded states, the uninsured rate decreased regardless of race (whites: relative decrease 56%, 4.3% to 1.9%; blacks: relative decrease 50%, 6.0 to 3.0%; both P < .0001) or county poverty level (low poverty: relative decrease 46%, 3.9% to 2.1%; high poverty: relative decrease 60%, 4.5% to 1.8%; both P < .0001). In non-expanded states, a decrease in uninsured levels was seen primarily in whites (relative decrease 9%, 7.8% to 7.1%, P < .0001; blacks: relative increase 7%, 9.9% to 10.6%, P = .37) and those living in areas with the lowest poverty (relative decrease 27%, 4.8% to 3.5%, P = .04; high poverty: relative increase 2%, 10.9% to 11.1%, P = .17). Blacks and those living in the highest poverty areas had the greatest level of benefit from full expansion (absolute benefit 2.0%-2.3%, P = .0093 and P = .0029, respectively).

CONCLUSIONS

Medicaid expansion in 2014 significantly decreased uninsured rates for cancer patients receiving radiation. Full expansion decreased rates of uninsurance to a greater degree and seemed to decrease racial and economic disparities.

Utilization trend and regimens of hypofractionated whole breast radiation therapy in the United States

PURPOSE

We aimed to evaluate the adoption of hypofractionated whole-breast irradiation (HF-WBI) over time and factors related to its adoption for patients undergoing lumpectomy. We also examined whether HF-WBI can increase the overall use of radiotherapy.

METHODS

Using data from the National Cancer Database between 2004 and 2013, we identified 528,051 invasive and 190,431 ductal carcinoma in situ (DCIS) patients who underwent lumpectomy. HF-WBI was defined as 2.5-3.33 Gy/fraction to the breast, whereas conventional therapy (CF-WBI) was defined as 1.8-2.0 Gy/fraction.

RESULTS

The usage of HF-WBI among invasive cancer patients increased from 0.7% in 2004 to 15.6% in 2013, and among DCIS patients, HF-WBI increased from 0.4% in 2004 to 13.4% in 2013. However, these changes only lead to a slight increase in the overall use of radiotherapy. Interestingly, for DCIS patients who lived ≥50 miles from hospitals, the uptake of HF-WBI translated to a moderate increase in the overall use of radiotherapy (58% in 2004 to 63% in 2013). Multivariable logistic regression showed that older age, node-negative or smaller tumor, living in mountain states, rural area, or ≥50 miles from hospitals, and treated in large or academic cancer centers were associated with elevated HF-WBI use. The median duration of finishing radiotherapy for HF-WBI was 26 days, compared to 47 days for CF-WBI.

CONCLUSIONS

Although HF-WBI can save 3 weeks of patient time, its adoption remained low in the US. There was only a slight increase in the overall use of radiotherapy among patients undergoing lumpectomy.

Comparison of SEER Treatment Data With Medicare Claims

BACKGROUND

The population-based Surveillance, Epidemiology, and End Results (SEER) registries collect information on first-course treatment, including surgery, chemotherapy, radiation therapy, and hormone therapy. However, the SEER program does not release data on chemotherapy or hormone therapy due to uncertainties regarding data completeness. Activities are ongoing to investigate the opportunity to supplement SEER treatment data with other data sources.

METHODS

Using the linked SEER-Medicare data, we examined the validity of the SEER data to identify receipt of chemotherapy and radiation therapy among those aged 65 and older diagnosed from 2000 to 2006 with bladder, female breast, colorectal, lung, ovarian, pancreas, or prostate cancer and hormone therapy among men diagnosed with prostate cancer at age 65 or older. Treatment collected by SEER was compared with treatment as determined by Medicare claims, using Medicare claims as the gold standard. The κ, sensitivity, specificity, positive predictive values, and negative predictive values were calculated for the receipt of each treatment modality.

RESULTS

The overall sensitivity of SEER data to identify chemotherapy, radiation, and hormone therapy receipt was moderate (68%, 80%, and 69%, respectively) and varied by cancer site, stage, and patient characteristics. The overall positive predictive value was high (>85%) for all treatment types and cancer sites except chemotherapy for prostate cancer.

CONCLUSIONS

SEER data should not generally be used for comparisons of treated and untreated individuals or to estimate the proportion of treated individuals in the population. Augmenting SEER data with other data sources will provide the most accurate treatment information.

Development of a Risk Prediction Model to Individualize Risk Factors for Surgical Site Infection After Mastectomy

BACKGROUND

Little data are available regarding individual patients' risk of surgical site infection (SSI) following mastectomy with or without immediate reconstruction. Our objective was to develop a risk prediction model for mastectomy-related SSI.

METHODS

Using commercial claims data, we established a cohort of women <65 years of age who underwent a mastectomy from 1 January 2004-31 December 2011. International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes were used to identify SSI within 180 days after surgery. SSI risk factors were determined with multivariable logistic regression using derivation data from 2004-2008 and validated with 2009-2011 data using discrimination and calibration measures.

RESULTS

In the derivation cohort, 595 SSIs were identified in 7607 (7.8 %) women, and 396 SSIs were coded in 4366 (9.1 %) women in the validation cohort. Independent risk factors for SSIs included rural residence, rheumatologic disease, depression, diabetes, hypertension, liver disease, obesity, pre-existing pneumonia or urinary tract infection, tobacco use disorder, smoking-related diseases, bilateral mastectomy, and immediate reconstruction. Receipt of home healthcare was associated with lower risk. The model performed equally in the validation cohort per discrimination (C-statistics 0.657 and 0.649) and calibration (Hosmer-Lemeshow p = 0.091 and 0.462 for derivation and validation, respectively). Three risk strata were created based on predicted SSI risk, which demonstrated good correlation with the proportion of observed infections in the strata.

CONCLUSIONS

We developed and internally validated an SSI risk prediction model that can be used to counsel women with regard to their individual risk of SSI post-mastectomy. Immediate reconstruction, diabetes, and smoking-related diseases were important risk factors for SSI in this non-elderly population of women undergoing mastectomy.

Big Data and machine learning in radiation oncology: State of the art and future prospects

Precision medicine relies on an increasing amount of heterogeneous data. Advances in radiation oncology, through the use of CT Scan, dosimetry and imaging performed before each fraction, have generated a considerable flow of data that needs to be integrated. In the same time, Electronic Health Records now provide phenotypic profiles of large cohorts of patients that could be correlated to this information. In this review, we describe methods that could be used to create integrative predictive models in radiation oncology. Potential uses of machine learning methods such as support vector machine, artificial neural networks, and deep learning are also discussed.

A Review of the Use of Medicare Claims Data in Plastic Surgery Outcomes Research

With a growing national emphasis in data transparency and reporting of public health data, it is essential for researchers to know more about Medicare claims data, the largest and most reliable source of health-care utilization and expenditure for individuals older than 65 years in the United States. This article provides an overview of Medicare claims data for plastic surgery outcomes research. We highlight essential information on various files included in Medicare claims data, strengths and limitations of the data, and ways to expand the use of existing data for research purposes. As of now, Medicare data are limited in providing adequate information regarding severity of diagnosed conditions, health status of individuals, and health outcomes after certain procedures. However, the data contain all health-care utilization and expenditures for services that are covered by Medicare Parts A, B, and D (inpatient, outpatient, ambulatory-based and physician-based services, and prescription drugs). Additionally, Medicare claims data can be used for longitudinal analysis of variations in utilization and cost of health-care services at the patient level and provider level. Linking Medicare claims data with other national databases and utilizing the ICD-10 coding system would further expand the use of these datasets in health services research.

Increased utilization of postmastectomy radiotherapy in the United States from 2003 to 2011 in patients with one to three tumor positive nodes

BACKGROUND AND OBJECTIVES

There have been few recent studies that have examined the use of postmastectomy radiotherapy (PMRT) for patients with 1-3 positive nodes.

METHODS

We utilized the National Cancer Data Base to examine trends in PMRT for 346,218 patients with Stage I-III breast cancer from 2003 to 2011. Neoadjuvant therapy cases were excluded. Log linear models examined trends in PMRT and logistic regressions were used to examine factors related to PMRT.

RESULTS

The proportion of pT1-2N1 patients receiving PMRT increased from 23.9% in 2003 to 36.4% in 2011 with an annual percent change (APC) of 6.2% (P < 0.001). There were significant increases in the use of PMRT amongst patients with one (APC = 7.7%), two (APC = 6.7%), and three (APC = 4.2%) positive nodes. In 2011, 27.8%, 43.8%, and 57.8% of patients with one, two or three positive nodes underwent PMRT, respectively. The number of positive nodes and tumor size were the strongest independent predictors of PMRT in the 1-3 node group; lymphovascular invasion, invasive lobular histology, and triple negative phenotypes were also associated with PMRT use.

CONCLUSION

PMRT for patients with pT1-2N1 disease has increased with the greatest increase seen in those with one tumor positive node. Tumor factors remain strong independent predictors of PMRT.

Comparison of survival at adult versus pediatric treatment centers for rare pediatric tumors in an adolescent and young adult (AYA) population in the State of Georgia

BACKGROUND

The type of treatment center where 15-21-year-old adolescent and young adult (AYA) patients with rare pediatric tumors achieve their best clinical outcome is unknown.

PROCEDURE

We performed a retrospective analysis using the Georgia Cancer Registry (GCR) of 15-21-year old patients with a malignant, rare pediatric tumor diagnosed during the period from 2000-2009. Patients were identified as being treated at one of five Georgia pediatric cancer centers or at an adult center. Data were analyzed for 10 year overall survival, patient characteristics associated with death, and patient characteristics present at diagnosis associated with choice of treatment center.

RESULTS

There was a total of 479 patients in our final study population, of which 379 (79.1%) were treated at an adult center and 100 (20.9%) were treated at a pediatric center. Patients treated at an adult center had a 10 year overall survival of 86% compared to 85% for patients treated at a pediatric center (P = 0.31). Race and poverty were not significantly associated with death. Patients with nasopharyngeal carcinoma (OR = 7.38; 95% CI = 2.30-23.75) and 'other carcinomas' (OR = 2.64; 95% CI = 1.25-5.60) were more likely to be treated at a pediatric center. Patients with higher-stage disease (OR = 4.24; 95% CI = 1.71-10.52) and higher poverty (OR = 2.32; 95% CI = 1.23-4.37) were also more likely to be treated at a pediatric center.

CONCLUSION

Our data suggest that there is no difference in survival for 15-21-year old patients with rare pediatric tumors when treated at an adult or pediatric center.

Individual, Area, and Provider Characteristics Associated With Care Received for Stages I to III Breast Cancer in a Multistate Region of Appalachia

PURPOSE

We describe individual, area, and provider characteristics associated with care patterns for early-stage breast cancer in Appalachian counties of Kentucky, North Carolina, Ohio, and Pennsylvania.

METHODS

Cases of stages I to III breast cancer from 2006 to 2008 were linked to Medicare claims occurring within 1 year of diagnosis. Rates of guideline-concordant endocrine therapy (n = 1,429), chemotherapy (n = 1,480), and radiation therapy (RT) after breast-conserving surgery were studied; RT was studied in women age ≥ 70 years with stage I estrogen receptor (ER) -positive/progesterone receptor (PR) -positive cancer, for whom RT was optional (n = 1,108), and in all others, for whom RT was guideline concordant (n = 1,422). Univariable and multivariable analyses were performed. Independent variables included age, race, county-level economic status, state, surgeon graduation year and volume, comorbidity, diagnosis year, Medicaid/Medicare dual status, histology, tumor size, tumor sequence, positive lymph nodes, ER/PR status, stage, trastuzumab use, and surgery type.

RESULTS

Population mean age was 74 years; 97% were white. For endocrine therapy, chemotherapy, and RT, guideline concordance was 76%, 48%, and 83%, respectively. Where it was optional, 77% received RT. Guideline-concordant endocrine therapy was lower in North Carolina versus Pennsylvania (odds ratio [OR], 0.60; 95% CI, 0.41 to 0.88) and higher if surgeon graduated between 1984 and 1988 versus ≥ 1989 (OR, 1.58; 95% CI, 1.06 to 2.34). Guideline-concordant chemotherapy varied significantly by state, county-level economic status, and surgeon volume. In guideline-concordant RT, lower surgeon volume (v highest) predicted RT use (OR, 1.63; 95% CI, 1.61 to 2.36). In optional RT, North Carolina residence (v Pennsylvania; OR, 0.29; 95% CI, 0.17 to 0.48) and counties with higher economic status (OR, 0.61; 95% CI, 0.40 to 0.94) predicated RT omission.

CONCLUSION

Notable variation in care by geographic and surgical provider characteristics provides targets for further research in underserved areas.

Treatment patterns for prostate cancer: comparison of Medicare claims data to medical record review

BACKGROUND

As evidence-based guidelines increasingly define standards of care, the accurate reporting of patterns of treatment becomes critical to determine if appropriate care has been provided. We explore the level of agreement between claims and record abstraction for treatment regimens for prostate cancer.

METHODS

Medicare claims data were linked to medical records abstraction using data from the Centers for Disease Control and Prevention's National Program of Cancer Registry-funded Breast and Prostate Patterns of Care study. The first course of therapy included surgery, radiation therapy (RT), and hormonal therapy with luteinizing hormone-releasing hormone agonists.

RESULTS

The linked sample included 2765 men most (84.7%) of whom had stage II prostate cancer. Agreement was excellent for surgery (κ=0.92) and RT (κ=0.92) and lower for hormonal therapy (κ=0.71); however, most of the discrepancies were due to greater number of patients reported who received hormonal therapy in the claims database than in the medical records database. For some standard multicomponent management strategies sensitivities were high, for example, hormonal therapy with either combination RT (86.9%) or cryosurgery (96.6%).

CONCLUSIONS

Medicare claims are sensitive for determining patterns of multicomponent care for prostate cancer and for detecting use of hormonal therapy when not reported in the medical records abstracts.

Muddy water? Variation in reporting receipt of breast cancer radiation therapy by population-based tumor registries

PURPOSE

To evaluate, in the setting of breast cancer, the accuracy of registry radiation therapy (RT) coding compared with the gold standard of Medicare claims.

METHODS AND MATERIALS

Using Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we identified 73,077 patients aged ≥66 years diagnosed with breast cancer in the period 2001-2007. Underascertainment (1 - sensitivity), sensitivity, specificity, κ, and χ(2) were calculated for RT receipt determined by registry data versus claims. Multivariate logistic regression characterized patient, treatment, and geographic factors associated with underascertainment of RT. Findings in the SEER-Medicare registries were compared with three non-SEER registries (Florida, New York, and Texas).

RESULTS

In the SEER-Medicare registries, 41.6% (n=30,386) of patients received RT according to registry coding, versus 49.3% (n=36,047) according to Medicare claims (P<.001). Underascertainment of RT was more likely if patients resided in a newer SEER registry (odds ratio [OR] 1.70, 95% confidence interval [CI] 1.60-1.80; P<.001), rural county (OR 1.34, 95% CI 1.21-1.48; P<.001), or if RT was delayed (OR 1.006/day, 95% CI 1.006-1.007; P<.001). Underascertainment of RT receipt in SEER registries was 18.7% (95% CI 18.6-18.8%), compared with 44.3% (95% CI 44.0-44.5%) in non-SEER registries.

CONCLUSIONS

Population-based tumor registries are highly variable in ascertainment of RT receipt and should be augmented with other data sources when evaluating quality of breast cancer care. Future work should identify opportunities for the radiation oncology community to partner with registries to improve accuracy of treatment data.

Severity of comorbid conditions and early-stage breast cancer therapy: linked SEER-Medicare data from 1993 to 2005

Comorbidity burden has been suggested as influencing early-stage breast cancer therapy but previous studies have not considered the severity of these comorbidities. Therefore, we examined the influence of comorbidity severity by age and race/ethnicity on early-stage breast cancer treatment over time. We used linked Surveillance, Epidemiology, and End Results (SEER)-Medicare data to determine whether comorbidity severity influences receipt of definitive and preferred early-stage breast cancer treatment and explains racial/ethnic and age disparities in receiving such therapy. Definitive surgical therapy was defined as any primary surgery other than breast conserving surgery (BCS) without radiation therapy (RT). Preferred surgical therapy was defined as BCS plus RT. Comorbidities were defined as either “unstable” (life threatening or difficult to control) or “stable” (less serious but with potential to influence daily activity). Surgical treatment trends from 1993 to 2005 were analyzed in regression models adjusting for comorbidity burden, age, and race/ethnicity in 93,596 elderly female Medicare beneficiaries with stage 1–2 invasive breast cancer. Receipt of BCS alone (compared with any definitive surgical therapy) was independently associated with neighborhood socioeconomic status, unmarried status (OR [odds ratio] 1.18, 95% CI: 1.12–1.23), tumor size (OR 0.78, 95% CI: 0.69–0.87 for tumors ≥4 cm vs. <2 cm), tumor grade (OR = 0.89, 0.88, and 0.81 for grades 2–4 vs. 1, respectively), stable comorbidities (OR = 0.76, 0.71, and 0.72 for 1, 2, and 3 vs. 0 stable comorbidities, respectively), and unstable comorbidities (OR 1.20, 95% CI: 1.14–1.28). Black women were 4–5% more likely to receive suboptimal therapy (BCS alone), even after adjusting for all available patient, tumor, and regional characteristics. Black race/ethnicity was associated with higher probability of receiving suboptimal treatment, independent of comorbidities, although we do not know whether this effect was due to clinicians' failure to offer RT or patients' failure to accept it.

Comorbidities, especially unstable comorbidities, adversely influence receipt of definitive and preferred early stage breast cancer therapy.

The cost of breast cancer screening in the Medicare population

BACKGROUND

Little is known about the cost to Medicare of breast cancer screening or whether regional-level screening expenditures are associated with cancer stage at diagnosis or treatment costs, particularly because newer breast cancer screening technologies, like digital mammography and computer-aided detection (CAD), have diffused into the care of older women.

METHODS

Using the linked Surveillance, Epidemiology, and End Results-Medicare database, we identified 137 274 women ages 66 to 100 years who had not had breast cancer and assessed the cost to fee-for-service Medicare of breast cancer screening and workup during 2006 to 2007. For women who developed cancer, we calculated initial treatment cost. We then assessed screening-related cost at the Hospital Referral Region (HRR) level and evaluated the association between regional expenditures and workup test utilization, cancer incidence, and treatment costs.

RESULTS

In the United States, the annual costs to fee-for-service Medicare for breast cancer screening-related procedures (comprising screening plus workup) and treatment expenditures were $1.08 billion and $1.36 billion, respectively. For women 75 years or older, annual screening-related expenditures exceeded $410 million. Age-standardized screening-related cost per beneficiary varied more than 2-fold across regions (from $42 to $107 per beneficiary); digital screening mammography and CAD accounted for 65% of the difference in screening-related cost between HRRs in the highest and lowest quartiles of cost. Women residing in HRRs with high screening costs were more likely to be diagnosed as having early-stage cancer (incidence rate ratio, 1.78 [95% CI, 1.40-2.26]). There was no significant difference in the cost of initial cancer treatment per beneficiary between the highest and lowest screening cost HRRs ($151 vs $115; P = .20).

CONCLUSIONS

The cost to Medicare of breast cancer screening exceeds $1 billion annually in the fee-for-service program. Regional variation is substantial and driven by the use of newer and more expensive technologies; it is unclear whether higher screening expenditures are achieving better breast cancer outcomes.

Using administrative health data to describe colorectal and lung cancer care in New South Wales, Australia: a validation study

Background

Monitoring treatment patterns is crucial to improving cancer patient care. Our aim was to determine the accuracy of linked routinely collected administrative health data for monitoring colorectal and lung cancer care in New South Wales (NSW), Australia.

Methods

Colorectal and lung cancer cases diagnosed in NSW between 2000 and 2002 were identified from the NSW Central Cancer Registry (CCR) and linked to their hospital discharge records in the NSW Admitted Patient Data Collection (APDC). These records were then linked to data from two relevant population-based patterns of care surveys. The main outcome measures were the sensitivity and specificity of data from the CCR and APDC for disease staging, investigative procedures, curative surgery, chemotherapy, radiotherapy, and selected comorbidities.

Results

Data for 2917 colorectal and 1580 lung cancer cases were analysed. Unknown disease stage was more common for lung cancer in the administrative data (18%) than in the survey (2%). Colonoscopies were captured reasonably accurately in the administrative data compared with the surveys (82% and 79% respectively; 91% sensitivity, 53% specificity) but all other colorectal or lung cancer diagnostic procedures were under-enumerated. Ninety-one percent of colorectal cancer cases had potentially curative surgery recorded in the administrative data compared to 95% in the survey (96% sensitivity, 92% specificity), with similar accuracy for lung cancer (16% and 17%; 92% sensitivity, 99% specificity). Chemotherapy (~40% sensitivity) and radiotherapy (sensitivity≤30%) were vastly under-enumerated in the administrative data. The only comorbidity that was recorded reasonably accurately in the administrative data was diabetes.

Conclusions

Linked routinely collected administrative health data provided reasonably accurate information on potentially curative surgical treatment, colonoscopies and comorbidities such as diabetes. Other diagnostic procedures, comorbidities, chemotherapy and radiotherapy were not well enumerated in the administrative data. Other sources of data will be required to comprehensively monitor the primary management of cancer patients.

Defining care provided for breast cancer based on medical record review or Medicare claims: information from the Centers for Disease Control and Prevention Patterns of Care Study

BACKGROUND

Description of care patterns is important as evidence-based guidelines increasingly dictate care. We explore the level of agreement between claims and record abstraction for guideline concordant multidisciplinary breast cancer care.

METHODS

From the U.S. Centers for Disease Control and Prevention's National Program of Cancer Registries Patterns of Care study, in which medical record abstraction of breast cancer and treatment was accomplished, cases include breast cancer where Medicare claims were available. Components of care were breast-conserving surgery (BCS), mastectomy, node assessment, radiation (RT), and chemotherapy (CTX), including specific chemotherapeutic agents, and combinations. We compared Medicare claims with record abstraction, and measured concordance using the kappa statistic and sensitivity.

RESULTS

The study sample consisted of 1762 women with stage 0 to 4 breast cancer. Level of agreement was excellent for surgery type (kappa = 0.84) and CTX (kappa = 0.89); agreement for RT therapy was slightly lower (kappa = 0.79). For standard multicomponent strategies, sensitivities and specificities were high; for example, 88.8%/93.5% for mastectomy plus nodes and 86.6%/95.4% for BCS plus nodes and RT. For selected, standard, multi-agent, adjuvant CTX regimens, sensitivities ranged from 66.3% to 68.8% (kappa 0.63-0.73).

CONCLUSIONS

Medicare claims, compared with chart abstraction, is a reliable method for determining patterns of multicomponent care for breast cancer.

Survival implications associated with variation in mastectomy rates for early-staged breast cancer

Despite a 20-year-old guideline from the National Institutes of Health (NIH) Consensus Development Conference recommending breast conserving surgery with radiation (BCSR) over mastectomy for woman with early-stage breast cancer (ESBC) because it preserves the breast, recent evidence shows mastectomy rates increasing and higher-staged ESBC patients are more likely to receive mastectomy. These observations suggest that some patients and their providers believe that mastectomy has advantages over BCSR and these advantages increase with stage. These beliefs may persist because the randomized controlled trials (RCTs) that served as the basis for the NIH guideline were populated mainly with lower-staged patients. Our objective is to assess the survival implications associated with mastectomy choice by patient alignment with the RCT populations. We used instrumental variable methods to estimate the relationship between surgery choice and survival for ESBC patients based on variation in local area surgery styles. We find results consistent with the RCTs for patients closely aligned to the RCT populations. However, for patients unlike those in the RCTs, our results suggest that higher mastectomy rates are associated with reduced survival. We are careful to interpret our estimates in terms of limitations of our estimation approach.

Sex variability in pediatric leukemia survival: large cohort evidence

Purpose. Sex disparities in pediatric leukemia have been previously reported, and male children continue to present with poorer survival. However, the observed disparities are not fully understood. This current study sought to examine disparities in survival by the sex, and to determine if tumor prognostic factors impact on these disparities. Patients and Methods. We used the Surveillance Epidemiology and End Results dataset of pediatric leukemia patients (ages 0–19 years) diagnosed in the United States from 1973 to 2006. There were 15,215 patients of whom 8,622 (65.7%) were boys and 6,593 (43.3%) were girls. The Kaplan-Meier survival estimates, log rank test, and Cox proportional hazard methods were used to assess the data. Results. The overall (both sexes) five-year survival rate was 67.9%. Girls had a survival rate of 70.1%, while the rate was 66.3% in boys. Girls had a significant 14% decreased risk of dying relative to boys, hazard ratio (HR) = 0.86, 99% CI = 0.80–0.93. There were significant differences between boys and girls with respect to tumor cell type, race, age at diagnosis, year of diagnosis, and number of primaries, P < 0.001. After controlling for these factors, the sex differences in survival persisted, with girls still less likely to die from leukemia compared to boys, adjusted HR (AHR) = 0.85, 99% CI = 0.72–1.00, P < 0.01. Conclusion. In a large population-based pediatric leukemia study, boys continued to show poorer survival. These disparities were not completely explained by treatment received, tumor prognostic or socio-demographic factors.

Underascertainment of radiotherapy receipt in Surveillance, Epidemiology, and End Results registry data

BACKGROUND

Surveillance, Epidemiology, and End Results (SEER) registry data have been used to suggest underuse and disparities in receipt of radiotherapy. Prior studies have cautioned that SEER may underascertain radiotherapy but lacked adequate representation to assess whether underascertainment varies by geography or patient sociodemographic characteristics. The authors sought to determine rates and correlates of underascertainment of radiotherapy in recent SEER data.

METHODS

The authors evaluated data from 2290 survey respondents with nonmetastatic breast cancer, aged 20 to 79 years, diagnosed from June of 2005 to February 2007 in Detroit and Los Angeles and reported to SEER registries (73% response rate). Survey responses regarding treatment and sociodemographic factors were merged with SEER data. The authors compared radiotherapy receipt as reported by patients versus SEER records. The authors then assessed correlates of radiotherapy underascertainment in SEER.

RESULTS

Of 1292 patients who reported receiving radiotherapy, 273 were coded as not receiving radiotherapy in SEER (underascertained). Underascertainment was more common in Los Angeles than in Detroit (32.0% vs 11.25%, P < .001). On multivariate analysis, radiotherapy underascertainment was significantly associated in each registry (Los Angeles, Detroit) with stage (P = .008, P = .026), income (P < .001, P = .050), mastectomy receipt (P < .001, P < .001), chemotherapy receipt (P < .001, P = .045), and diagnosis at a hospital that was not accredited by the American College of Surgeons (P < .001, P < .001). In Los Angeles, additional significant variables included younger age (P < .001), nonprivate insurance (P < .001), and delayed receipt of radiotherapy (P < .001).

CONCLUSIONS

SEER registry data as currently collected may not be an appropriate source for documentation of rates of radiotherapy receipt or investigation of geographic variation in the radiation treatment of breast cancer.

Outcomes following local therapy for early-stage breast cancer in non-trial populations

Recent studies suggest trends toward more mastectomies for primary breast cancer treatment. We assessed survival after mastectomy and breast-conserving surgery (BCS) with radiation for early-stage breast cancer among non-selected populations of women and among women similar to those in clinical trials. Using population-based data from Surveillance Epidemiology, and End Results cancer registries linked with Medicare administrative data from 1992 to 2005, we conducted propensity score analysis of survival following primary therapy for early-stage breast cancer, including BCS with radiation, BCS without radiation, mastectomy with radiation, and mastectomy without radiation. Adjusted survival was greatest among women who had BCS with radiation (median survival = 10.98 years). Compared with this group, mortality was higher among women who had mastectomy without radiation (median survival 10.04 years, adjusted hazard ratio (HR) = 1.19, 95% confidence interval (CI) = 1.14-1.23), mastectomy with radiation (median survival 10.02 years, HR = 1.20, 95% CI = 1.14-1.27), and BCS without radiation (median survival 7.63 years, HR = 1.81, 95% CI = 1.70-1.92). Among women representative of those eligible for clinical trials (age ≤70 years, Charlson comorbidity score = 0/1, and stage 1 tumors), there were no differences in survival for women who underwent BCS with radiation or mastectomy. In conclusion, after careful adjustment for differences in patient, physician, and hospital characteristics, we found better survival for BCS with radiation versus mastectomy among older early-stage breast cancer patients, with no difference in survival for BCS with radiation versus mastectomy among women representative of those in clinical trials. These findings are reassuring in light of recent trends towards more aggressive primary breast cancer therapy.

Pattern of care and survival in older women with breast cancer in India

Purpose:To determine the pattern of care and survival in older patients with breast cancer.

Methods:The study population included 228 women aged ≥60 years with breast cancer treated between 1992 and 2002. Analysis was done for surgery, radiotherapy (RT), chemotherapy and hormonal therapy. Outcomes studied were locoregional recurrence (LRR) distant metastases, disease-free survival (DFS) and overall survival (OS) using univariate and multivariate analyses. Kaplan–Meier method was used to estimate DFS and OS.

Results:Mastectomy was done in 208 (91%) patients and conservative breast surgery (CBS) only in 20 (9%) patients. Majority of the patients received adjuvant RT 179 (78.5%). Chemotherapy was given to 49 (21.5%) patients and hormones to 204 (89.5%) patients. LRR with or without distant metastases was 7% and distant metastasis rate was 19.3%. DFS at 10 years was 69%. With RT, DFS was 76% in patients aged <65 years and 73% in aged ≥65 years (p= 0.13). It was 73 and 86%, respectively, with chemotherapy (p= 0.041). DFS with hormones was 96% in patients aged ≥65 years and 79% in aged <65 years (p= 0.028). The OS was 74% at 10 years. RT improved OS in all patients. OS with chemotherapy was 94% in patients ≥65 years, and 82% in patients <65 years (p= 0.044). With hormonal therapy OS was 96% in patients aged ≥65 years and 78% in patients <65 years (p= 0.020).

Conclusion:CBS rate and chemotherapy use is very low in elderly women with breast cancer in India. Adjuvant RT, chemotherapy and hormonal therapy offered a therapeutic advantage in these patients.

Racial disparities in colorectal cancer survival: to what extent are racial disparities explained by differences in treatment, tumor characteristics, or hospital characteristics?

BACKGROUND

Racial/ethnic differences in colorectal cancer (CRC) survival have been documented throughout the literature. However, the reasons for these disparities are difficult to decipher. The objective of this analysis was to determine the extent to which racial/ethnic disparities in survival are explained by differences in sociodemographics, tumor characteristics, diagnosis, treatment, and hospital characteristics.

METHODS

A cohort of 37,769 Medicare beneficiaries who were diagnosed with American Joint Committee on Cancer stages I, II, and III CRC from 1992 to 2002 and resided in 16 Surveillance, Epidemiology, and End Results (SEER) regions of the United States was identified in the SEER-Medicare linked database. Survival was estimated using the Kaplan-Meier method. Cox proportional hazards modeling was used to estimate hazard ratios (HRs) of mortality and 95% confidence intervals (CIs).

RESULTS

Black patients had worse CRC-specific survival than white patients, but the difference was reduced after adjustment (adjusted HR [aHR], 1.24; 95% CI, 1.14-1.35). Asian patients had better survival than white patients after adjusting for covariates (aHR, 0.80; 95% CI, 0.70-0.92) for stages I, II, and III CRC. Relative to Asians, blacks and whites had worse survival after adjustment (blacks: aHR, 1.56; 95% CI, 1.33-1.82; whites: aHR, 1.26; 95% CI, 1.10-1.44). Comorbidities and socioeconomic Status were associated with a reduction in the mortality difference between blacks and whites and blacks and Asians.

CONCLUSIONS

Comorbidities and SES appeared to be more important factors contributing to poorer survival among black patients relative to white and Asian patients. However, racial/ethnic differences in CRC survival were not fully explained by differences in several factors. Future research should further examine the role of quality of care and the benefits of treatment and post-treatment surveillance in survival disparities.

Does Type of Tumor Histology Impact Survival among Patients with Stage IIIB/IV Non-Small Cell Lung Cancer Treated with First-Line Doublet Chemotherapy?

Chemotherapy regimens may have differential efficacy by histology in nonsmall cell lung cancer (NSCLC). We examined the impact of histology on survival of patients (N = 2,644) with stage IIIB/IV NSCLC who received first-line cisplatin/carboplatin plus gemcitabine (C/C+G) and cisplatin/carboplatin plus a taxane (C/C+T) identified retrospectively in the SEER cancer registry (1997-2002). Patients with squamous and nonsquamous cell carcinoma survived 8.5 months and 8.1 months, respectively (P = .018). No statistically significant difference was observed in survival between C/C+G and C/C+T in both histologies. Adjusting for clinical and demographic characteristics, the effect of treatment regimen on survival did not differ by histology (P for interaction = .257). There was no statistically significant difference in hazard of death by histology in both groups. These results contrast the predictive role of histology and improved survival outcomes observed for cisplatin-pemetrexed regimens in advanced nonsquamous NSCLC.

Patterns and correlates of adjuvant radiotherapy receipt after lumpectomy and after mastectomy for breast cancer

PURPOSE

To use patient self-report to provide more valid estimates of whether radiotherapy (RT) is underutilized than possible with registry data, as well as to evaluate for disparities and the influence of preferences and provider interactions.

METHODS

We considered 2,260 survey respondents who had nonmetastatic breast cancer, were age 20 to 79 years, were diagnosed between July 2005 and February 2007 in Detroit and Los Angeles, and reported to Surveillance, Epidemiology and End Results (SEER) registries (72% response rate). Survey responses were merged with SEER data. We assessed rates and correlates of RT receipt among all patients with invasive cancer receiving breast-conserving surgery (BCS) and among patients undergoing mastectomy with indications for RT (ie, positive lymph nodes or T3-4 tumors).

RESULTS

Among 904 patients undergoing BCS with strong indications for RT, 95.4% received RT, and 77.6% received RT among the 135 patients undergoing mastectomy with strong indications (P < .001). Among 114 patients undergoing BCS with weaker indications (ie, elderly) for RT, 80.0% received treatment, and 47.5% received RT among the 164 patients undergoing mastectomy with weaker indications (T1N1, T2N1, or T3N0 disease; P < .001). On multivariate analysis, surgery type (P < .001), indication strength (P < .001), age (P = .005), comorbidity (P < .001), income (P = .03), patient desire to avoid RT (P < .001), level of surgeon involvement in decision to have radiation (P < .001), and SEER site (P < .001) were significantly associated with likelihood of RT receipt.

CONCLUSION

RT receipt was consistently high across sociodemographic subgroups after BCS but was lower after mastectomy, even among patients with strong indications for treatment, in whom clinical benefit is similar. Surgeon involvement had a strong influence on RT receipt.

Chemotherapy-associated toxicity in a large cohort of elderly patients with non-small cell lung cancer

BACKGROUND

The objective of this study was to examine the risks for short-term (< or =3 months) and long-term (>3 months) chemotherapy-associated toxicities in a large population-based cohort of patients with non-small cell lung cancer from 1991 to 2002.

METHODS

The population consisted of 41,361 men and 30,804 women > or =65 years identified from the Surveillance, Epidemiology, and End Results-Medicare-linked database. The incidence of 50 toxicity-associated end points was calculated for 14 chemotherapy agents. Short- and long-term toxicities with a > or =2-fold increase in incidence compared with the no-chemotherapy group were defined as chemotherapy-associated toxicities. Hazard ratios and 95% confidence intervals for the risk of toxicity were calculated for the four most common chemotherapy agents for non-small cell lung cancer: cisplatin/carboplatin, paclitaxel, vinorelbine/vinblastine, and gemcitabine.

RESULTS

The most common short-term toxicities (9.2-60%) included acute anemia, nausea, and neutropenia. The most common long-term toxicities (15-37%) included acute anemia, respiratory failure, pulmonary fibrosis, dehydration, neutropenia, nausea, and fever. Multivariate analysis for selected chemotherapies demonstrated that after adjusting for other risk factors and confounders, some short-term toxicities became nonsignificant; however, almost all long-term toxicities remained significant. Long-term toxicity increased over time and was more likely in women, minority populations, those with fewer baseline comorbidities, and across disease stages.

CONCLUSIONS

The administration of various chemotherapy agents for non-small cell lung was associated with a number of short- and long-term toxicities. The projected survival benefits of chemotherapy must be weighed against the risk of long-term toxicities.

Cardiac toxicity in association with chemotherapy and radiation therapy in a large cohort of older patients with non-small-cell lung cancer

BACKGROUND

The study's objective was to investigate the risks of developing cardiac disorders following the administration of chemotherapy and radiation therapy in patients with non-small-cell lung cancer (NSCLC).

METHODS

The study consisted of 34 209 patients aged > or =65 years with American Joint Committee on Cancer stages I-IV NSCLC identified from the Surveillance, Epidemiology, and End Result-Medicare linked database (1991-2002) who were free of cardiac disorders at NSCLC diagnosis.

RESULTS

There were significant associations between the use of chemotherapy/radiation and the risks of developing ischemic heart disease, conduction disorders, cardiac dysfunction, and heart failure. The absolute risks for cardiac dysfunction increased with the administration of chemotherapy-only and radiation-only, and incrementally with chemoradiation. Men, blacks, older patients, those with higher comorbidity scores, and advanced disease were at higher risk. The risk for ischemic heart disease increased when radiation/chemoradiation were rendered to the left lung and both lungs and for cardiac dysfunction, radiation administered to the left lung.

CONCLUSIONS

There were significant associations especially for cardiac dysfunction with use of chemotherapy/radiation therapy and risks of developing cardiac toxicity in NSCLC patients. The risks of treatment-associated cardiac toxicity, specifically ischemic heart disease and cardiac dysfunction, were greatest among those with left-sided lung tumors.

Development and validation of a prediction model for the risk of developing febrile neutropenia in the first cycle of chemotherapy among elderly patients with breast, lung, colorectal, and prostate cancer

Purpose

Current guidelines recommend prophylactic use of granulocyte-colony stimulating factors (G-CSF) when febrile neutropenia (FN) risk is greater than 20%. Advanced age is a risk factor for FN; however, little is known about the impact of other factors on the incidence of FN in an older population.

Patients and methods

We analyzed SEER-Medicare data (1994–2005) to develop and validate a prediction model for hospitalization with fever, infection, or neutropenia occurring after chemotherapy initiation for patients with breast, colorectal, prostate, and lung cancer.

Results

In multivariate analysis (N = 58,053) independent predictors of FN included advanced stage at diagnosis [stage 2 (OR 1.29; 95% CI: 1.09–1.53), stage 3 (1.38; 95% CI: 1.19–1.60), and stage 4 (1.57; 95% CI: 1.35–1.83)], number of associated comorbid conditions [one condition (1.13; 95% CI: 1.02–1.28), two conditions (1.39; 95% CI: 1.22–1.57), and three or more conditions (1.81; 95% CI: 1.61–2.04)], receipt of myelosuppressive chemotherapy (1.11; 95% CI: 0.94–1.32), and receipt of chemotherapy within 1 month of diagnosis [1 to 3 months (0.70; 95% CI: 0.62–0.80) and greater than 3 months (0.63; 95% CI: 0.55–0.73)].

Conclusion

We created a prediction model for febrile neutropenia with first cycle of chemotherapy in a large population of elderly patients with common malignancies.

A method to predict breast cancer stage using Medicare claims

Background

In epidemiologic studies, cancer stage is an important predictor of outcomes. However, cancer stage is typically unavailable in medical insurance claims datasets, thus limiting the usefulness of such data for epidemiologic studies. Therefore, we sought to develop an algorithm to predict cancer stage based on covariates available from claims-based data.

Methods

We identified a cohort of 77,306 women age ≥ 66 years with stage I-IV breast cancer, using the Surveillence Epidemiology and End Results (SEER)-Medicare database. We formulated an algorithm to predict cancer stage using covariates (demographic, tumor, and treatment characteristics) obtained from claims. Logistic regression models derived prediction equations in a training set, and equations' test characteristics (sensitivity, specificity, positive predictive value (PPV), and negative predictive value [NPV]) were calculated in a validation set.

Results

Of the entire sample of women diagnosed with invasive breast cancer, 51% had stage I; 26% stage II; 11% stage III; and 4% stage IV disease. The equation predicting stage IV disease achieved sensitivity of 81%, specificity 89%, positive predictive value (PPV) 24%, and negative predictive value (NPV) 99%, while the equation distinguishing stage I/II from stage III disease achieved sensitivity 83%, specificity 78%, PPV 98%, and NPV 31%. Combined, the equations most accurately identified early stage disease and ascertained a sample in which 98% of patients were stage I or II.

Conclusions

A claims-based algorithm was utilized to predict breast cancer stage, and was particularly successful when used to identify early stage disease. These prediction equations may be applied in future studies of breast cancer patients, substantially improving the utility of claims-based studies in this group. This method may similarly be employed to develop algorithms permitting claims-based epidemiologic studies of patients with other cancers.

Racial disparities and survival for nonsmall-cell lung cancer in a large cohort of black and white elderly patients

BACKGROUND

This study aimed to examine disparities in survival and associated factors for patients with nonsmall-cell lung cancer (NSCLC) and to determine whether racial disparities varied over time (1991-1995, 1996-1999, and 2000-2002).

METHODS

The authors studied 70,901 patients aged>or=65 years with stage I-IV NSCLC identified from Surveillance, Epidemiology, and End Results/Medicare data. Multivariate time-to-event survival analyses were completed using Cox proportional regression modeling.

RESULTS

The 5-year observed lung cancer-specific survival rates were 52.7% for whites and 47.5% for blacks with stage I-II disease, and 17.7% and 19.6% for whites and blacks, respectively at stages III-IV. After controlling for standard treatment, socioeconomic status (SES), and other factors, there were no significant differences in all-cause mortality, or lung cancer-specific mortality between black and white patients with stage I-II or III-IV lung cancer. However, blacks had an increased risk for overall all-cause mortality at stage I-IV (hazard ratio [HR], 1.24; 95% confidence interval, 1.13-1.35), and during 2000-2002 at stage III-IV for all-cause mortality (HR, 1.22; 95% CI, 1.02-1.47) and lung cancer-specific mortality (HR, 1.24; 95% CI,1.01-1.53). Standard treatment was significantly associated with increased survival, whereas poor SES was associated with increased mortality.

CONCLUSIONS

There were no significant differences in survival between blacks and whites with NSCLC within stage stratifications after adjusting for covariates, except for black patients at overall stage for all-cause mortality and at stage III-IV diagnosed in 2000-2002. Receiving stage-specific evidence-based standard therapy was associated with significantly increased survival.

Effectiveness of radiation therapy for elderly patients with unresected stage I and II non-small cell lung cancer

RATIONALE

Radiotherapy (RT) is considered the standard treatment for patients with stage I or II non-small lung cancer who are not surgical candidates because of comorbities or preferences against surgery.

OBJECTIVES

To compare the outcomes of patients treated with RT alone with those who were untreated to assess the effect of RT on survival.

METHODS

Using the Surveillance, Epidemiology and End Results (SEER) registry linked to Medicare files, we identified 6,065 unresected patients with histologically confirmed stage I and stage II non-small cell lung cancer, diagnosed between 1992 and 2002. We used propensity score methods and instrumental variable analysis to control for the possible effects of known as well as unmeasured confounders.

MEASUREMENTS AND MAIN RESULTS

Overall, 59% of patients received RT. The overall and lung cancer-specific survival of unresected patients treated with RT was significantly better compared with the untreated cases (P < 0.0001 for both comparisons). RT was associated with a 6-month improvement in median overall survival. Propensity score analyses showed that RT was associated with improved overall (hazard ratio, 0.74; 95% confidence interval, 0.70-0.78) and lung cancer-specific survival (hazard ratio, 0.73; 95% confidence interval, 0.69-0.78). Instrumental variable analysis also indicated improved outcomes among patients treated with RT.

CONCLUSIONS

RT improves survival of elderly patients with unresected stage I or II lung cancer. These results should be confirmed in prospective trials.