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result(s) for
"Camacho, Fabian"
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Effects of Adjuvant Endocrine Therapy Adherence and Radiation on Recurrence and Survival Among Older Women with Early-Stage Breast Cancer
by
Showalter, Shayna L
,
Fabian, Camacho T
,
Keim-Malpass, Jessica
in
Breast cancer
,
Cancer therapies
,
Endocrine therapy
2021
BackgroundThe Cancer and Leukemia Group-B 9343 (CALGB 9343) trial demonstrated that women aged ≥ 70 years with early-stage breast cancer can safely omit radiation therapy (RT) and be treated with breast-conserving surgery (BCS) and adjuvant endocrine therapy (AET) alone. AET adherence is low, leaving an undertreated cohort who may be at increased risk of recurrence and death. We hypothesized that AET adherence and adjuvant treatment choice impact recurrence and survival among CALGB 9343 eligible women.Patients and MethodsSEER-Medicare was used to identify CALGB 9343 eligible women who underwent BCS between 2007 and 2016. Medicare claims were used to identify AET use, and the proportion of days covered by AET was used to categorize adherent (PDC ≥ 0.80) versus nonadherent patients (PDC < 0.80). Recurrence-free, cancer-specific, and overall survival were assessed using Cox proportional hazards models.ResultsIn total, 10,719 women were identified, of whom 780 (7.3%) underwent BCS alone, 1490 (13.9%) underwent BCS + RT, 1663 (15.5%) underwent BCS + AET, and 6786 (63.3%) had BCS + RT + AET. Among women treated with BCS + AET, adherent patients had lower recurrence than did nonadherent patients (HR = 0.65, 95% CI: 0.50–0.85). With respect to adjuvant treatment combinations, there was no recurrence difference between the BCS + RT + AET group and BCS + AET group (HR = 0.81, 95% CI: 0.54–1.21). There was equivalent cancer-specific but worse overall survival in the BCS + AET group versus the BCS + AET + RT group.ConclusionsWhile BCS + RT + AET may represent overtreatment for some, AET nonadherent women who omit RT are at risk for worse outcomes. Treatment decisions regarding RT omission should be tailored to the individual patient, taking into consideration the chances of AET nonadherence and the patients’ own risk tolerance.
Journal Article
Predicting adjuvant endocrine therapy initiation and adherence among older women with early-stage breast cancer
by
Keim-Malpass, Jessica
,
Anderson, Roger T.
,
Meneveau, Max O.
in
Adjuvant treatment
,
Analysis
,
Breast cancer
2020
Purpose
The CALGB 9343 trial demonstrated that women age 70 or older with early-stage, estrogen receptor positive (ER +) breast cancer (BC) may safely forgo radiation therapy (RT) and be treated with breast conserving surgery followed by adjuvant endocrine therapy (AET) alone. However, most patients in this population still undergo RT in part because AET adherence is low. We sought to develop a predictive model for AET initiation and adherence in order to improve decision-making with respect to RT omission.
Methods
Women ages 70 and older with early-stage, ER + BC were identified using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Comorbidities, socioeconomic measures, prescription medications, and demographics were collected as potential predictors. Bivariate analysis was performed to identify factors associated with AET initiation and adherence. Stepwise selection of significant predictors was used to develop logistic regression classifiers for initiation and adherence. Model performance was evaluated using the c-statistic and other measures.
Results
11,037 patients met inclusion criteria. Within the cohort, 8703 (78.9%) patients initiated AET and 6685 (60.6%) were adherent to AET over 1 year. Bivariate predictors of AET initiation were similar to predictors of adherence. The best AET initiation and adherence classifiers were poorly predictive with c-statistics of 0.65 and 0.60, respectively.
Conclusions
The best models in the present study were poorly predictive, demonstrating that the reasons for initiation and adherence to AET are complex and individual to the patient, and therefore difficult to predict. Initiation and adherence to AET are important factors in decision-making regarding whether or not to forgo adjuvant RT. In order to better formulate treatment plans for this population, future work should focus on improving individual prediction of AET initiation and adherence.
Journal Article
Number Concentration, Size Distribution, and Lung-Deposited Surface Area of Airborne Particles in Three Urban Areas of Colombia
by
Mateus-Fontecha, Lady
,
Archila-Peña, David
,
Pachón, Jorge E.
in
Air pollution
,
Air quality
,
Air quality management
2025
Airborne particulate matter is a major pollutant globally due to its impact on atmospheric processes and human health. Depending on their aerodynamic size, particles can penetrate the respiratory system, with ultrafine particles (UFPs) reaching the bloodstream and affecting vital organs. This study investigates the particle number size distribution (PNSD), particle number concentration (PNC), and lung-deposited surface area (LDSA) in Bogotá, Cali, and Palmira, Colombia. Measurements were conducted at four sites representing different urban and industrial backgrounds using an Electrical Low-Pressure Impactor (ELPI+). Due to the availability and operation of the device, observations were limited to a few days, so the results of this study are indicative and not generalized for the cities. UFP concentrations were highest in Cali (28,399 cm−3), three times higher than in San Cristóbal, Bogotá. Fine particles (FPs) exhibited similar patterns across the three cities, with higher concentrations in San Cristóbal (2421 cm−3). Coarse particles (CPs) were most prevalent in Palmira (41.37 cm−3), and the highest LDSA values were recorded in Palmira and Cali (>80 µm2/cm3), indicating a higher potential for respiratory deposition. These findings highlight the importance of PNSD in health risk assessment in urban areas, providing valuable insights for future studies and strategies to manage air quality in Colombia.
Journal Article
Correction to: Effects of Adjuvant Endocrine Therapy Adherence and Radiation on Recurrence and Survival Among Older Women with Early-Stage Breast Cancer
A correction to this paper has been published: https://doi.org/10.1245/s10434-021-10216-6
Journal Article
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
2019
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.
Journal Article
Associations between initiating antihypertensive regimens on stage I–III colorectal cancer outcomes: A Medicare SEER cohort analysis
by
Chammas, Roger
,
Camacho, Fabian T.
,
Flausino, Lucas E.
in
Adrenergic beta-Antagonists - therapeutic use
,
Aged
,
Aged, 80 and over
2021
Purpose Colorectal cancer (CRC) diagnosis is associated with high mortality in the United States and thus warrants the study of novel treatment approaches. Vascular changes are well observed in cancers and evidence indicates that antihypertensive (AH) medications may interfere with both tumor vasculature and in recruiting immune cells to the tumor microenvironment based on preclinical models. Extant literature also shows that AH medications are correlated with improved survival in some forms of cancer. Thus, this study sought to explore the impact of AH therapies on CRC outcomes. Patients and Methods This study was a non‐interventional, retrospective analysis of patients aged 65 years and older with CRC diagnosed from January 1, 2007 to December 31st, 2012 in the Surveillance, Epidemiology, and End‐Results (SEER)‐Medicare database. The association between AH drug utilization on AJCC stage I–III CRC mortality rates in patients who underwent treatment for cancer was examined using Cox proportional hazards models. Results The study cohort consisted of 13,982 patients diagnosed with CRC. Adjusted Cox proportional hazards regression showed that among these patients, the use of AH drug was associated with decreased cancer‐specific mortality (HR: 0.79, 95% CI: 0.75–0.83). Specifically, ACE inhibitors (hazard ratio [HR]: 0.84, 95% CI: 0.80–0.87), beta‐blockers (HR: 0.87, 95% CI: 0.84–0.91), and thiazide diuretics (HR: 0.83, 95% CI: 0.80–0.87) were found to be associated with decreased mortality. An association was also found between adherence to AH therapy and decreased cancer‐specific mortality (HR: 0.94, 95% CI: 0.90–0.98). Conclusion Further research needs to be performed, but AH medications may present a promising, low‐cost pathway to supporting CRC treatment for stage I–III cancers. The use of antihypertensive agents following colorectal cancer diagnosis is associated with lower mortality (both all‐cause and cancer‐specific) in elderly Medicare patients. Among the studied classes of antihypertensives, ACE inhibitors and beta‐blockers seem to be associated with protective associations.
Journal Article
Spatial analysis of colorectal cancer outcomes and socioeconomic factors in Virginia
2021
Background
Colorectal cancer (CRC) disparities vary by country and population group, but often have spatial features. This study of the United States state of Virginia assessed CRC outcomes, and identified demographic, socioeconomic and healthcare access contributors to CRC disparities.
Methods
County- and city-level cross-sectional data for 2011–2015 CRC incidence, mortality, and mortality-incidence ratio (MIR) were analyzed for geographically determined clusters (hotspots and cold spots) and their correlates. Spatial regression examined predictors including proportion of African American (AA) residents, rural-urban status, socioeconomic (SES) index, CRC screening rate, and densities of primary care providers (PCP) and gastroenterologists. Stationarity, which assesses spatial equality, was examined with geographically weighted regression.
Results
For incidence, one CRC hotspot and two cold spots were identified, including one large hotspot for MIR in southwest Virginia. In the spatial distribution of mortality, no clusters were found. Rurality and AA population were most associated with incidence. SES index, rurality, and PCP density were associated with spatial distribution of mortality. SES index and rurality were associated with MIR. Local coefficients indicated stronger associations of predictor variables in the southwestern region.
Conclusions
Rurality, low SES, and racial distribution were important predictors of CRC incidence, mortality, and MIR. Regions with concentrations of one or more factors of disparities face additional hurdles to improving CRC outcomes. A large cluster of high MIR in southwest Virginia region requires further investigation to improve early cancer detection and support survivorship. Spatial analysis can identify high-disparity populations and be used to inform targeted cancer control programming.
Journal Article
Predicting Late-stage Breast Cancer Diagnosis and Receipt of Adjuvant Therapy
by
Marshall, Vince
,
Camacho, Fabian T.
,
Tan, Xi
in
Adult
,
Breast cancer
,
Breast Neoplasms - diagnosis
2015
PURPOSE:The 2-step floating catchment area (2SFCA) method of measuring access to care has never been used to study cancer disparities in Appalachia. First, we evaluated the 2SFCA method in relation to traditional methods. We then examined the impact of access to mammography centers and primary care on late-stage breast cancer diagnosis and receipt of adjuvant hormonal therapy.
METHODS:Cancer registries from Pennsylvania, Ohio, Kentucky, and North Carolina were linked with Medicare data to identify the stage of breast cancer diagnosis for Appalachia women diagnosed between 2006 and 2008. Women eligible for adjuvant therapy had stage I, II, or III diagnosis; mastectomy or breast-conserving surgery; and hormone receptor–positive breast cancers. Geographically weighted regression was used to explore nonstationarity in the demographic and spatial access predictor variables.
RESULTS:Over 21% of 15,299 women diagnosed with breast cancer had late-stage (stages III–IV) diagnosis. Predictors included age at diagnosis [odds ratio (OR)=0.86; P<0.001], insurance status (OR=1.32; P<0.001), county primary care to population ratio (OR=0.95; P<0.001), and primary-care 2SFCA score (OR=0.96; P=0.006). Only 46.9% of eligible women received adjuvant hormonal therapy, and predictors included comorbidity status (OR=1.18; P=0.047), county economic status (OR=1.32; P=0.006), and mammography center 2SFCA scores (OR=1.12; P=0.021).
CONCLUSIONS:Methodologically, the 2SFCA method offered the greatest predictive validity of the access measures examined. Substantively, rates of late-stage breast cancer diagnosis and adjuvant hormonal therapy are substandard in Appalachia.
Journal Article
Evaluating and comparing methods for measuring spatial access to mammography centers in Appalachia
2016
This study evaluated spatial access to mammography centers in Appalachia using both traditional access measures and the two-step floating catchment area (2SFCA) method. Ratios of county mammography centers to women age 45 and older, driving time to nearest mammography facility, and various 2SFCA approaches were compared throughout Pennsylvania, Ohio, Kentucky, and North Carolina. Closest travel time measures favored urban areas. The 2SFCA method produced varied results depending on the parameters chosen. Appalachia areas had greater travel times to their closest mammography center. Appalachia areas in OH and NC had worse 2SFCA scores than non-Appalachia areas of the same states. A relative 2SFCA approach, the spatial access ratio method, was recommended because it helped minimize the differences between various 2SFCA approaches.
Journal Article