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INTRODUCTION: National guidelines specify against immediate breast reconstruction (IBR) among inflammatory breast cancer (IBC) patients. However, limited data exist regarding this practice. We report practice patterns and oncologic outcomes among nonmetastatic IBC patients receiving trimodality therapy, with or without IBR. METHODS: Using the National Cancer Database, we identified nonmetastatic IBC patients treated with trimodality therapy from 2004 to 2016. Primary outcome was overall survival (OS), assessed on unadjusted analysis using Kaplan-Meier estimates and on adjusted analysis using multivariable Cox proportional hazards and inverse probability weighting (IPW) models. OS analysis was also conducted with propensity score matched (PSM) cohorts. Secondary outcomes included IBR utilization rates, time to postmastectomy radiotherapy (PMRT), and surgical outcomes. RESULTS: 6589 women were included, including 5954 (90.4%) non-reconstructed and 635 (9.6%) IBR. Among IBR recipients, 250 (39.4%) underwent autologous reconstruction, 171 (26.9%) underwent implant-based reconstruction, and 214 (33.7%) unspecified. IBR utilization increased from 6.3% to 10.1% from 2004 to 2016 at a 4% average annual growth rate (P < 0.001). Median follow-up was 43 and 45 months for IBR and non-reconstructed patients, respectively (P = 0.29). On Cox multivariable analysis, IBR was associated with improved OS (HR 0.63, 95% CI 0.44-0.90, P = 0.01), but this association was not significant on IPW analysis (P = 0.06). In PSM cohorts, this association remained significant (HR 0.60, 95% CI 0.40-0.92, P = 0.02). Margin status, time to PMRT, 30-day readmission, and 30-/90-day mortality did not differ between groups (all P > 0.05). CONCLUSION: Although not endorsed by national guidelines, IBR is increasing among IBC patients; however, more granular data are needed to determine oncologic safety.
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Neoplasias de la Mama , Neoplasias Inflamatorias de la Mama , Mamoplastia , Neoplasias de la Mama/cirugía , Femenino , Humanos , Neoplasias Inflamatorias de la Mama/cirugía , Estimación de Kaplan-Meier , Mastectomía , Radioterapia Adyuvante , Estudios RetrospectivosRESUMEN
BACKGROUND: Despite increasing utilization of proton-beam therapy (PBT) in the postprostatectomy setting, no data exist regarding toxicity outcomes relative to intensity-modulated radiotherapy (IMRT). The authors compared acute and late genitourinary (GU) and gastrointestinal (GI) toxicity outcomes in patients with prostate cancer (PC) who received treatment with postprostatectomy IMRT versus PBT. METHODS: With institutional review board approval, patients with PC who received adjuvant or salvage IMRT or PBT (70.2 gray with an endorectal balloon) after prostatectomy from 2009 through 2017 were reviewed. Factors including combined IMRT and PBT and/or concurrent malignancies prompted exclusion. A case-matched cohort analysis was performed using nearest-neighbor 3-to-1 matching by age and GU/GI disorder history. Logistic and Cox regressions were used to identify univariate and multivariate associations between toxicities and cohort/dosimetric characteristics. Toxicity-free survival (TFS) was assessed using the Kaplan-Meier method. RESULTS: Three hundred seven men (mean ± SD age, 59.7 ± 6.3 years; IMRT, n = 237; PBT, n = 70) were identified, generating 70 matched pairs. The median follow-up was 48.6 and 46.1 months for the IMRT and PBT groups, respectively. Although PBT was superior at reducing low-range (volumes receiving 10% to 40% of the dose, respectively) bladder and rectal doses (all P ≤ .01), treatment modality was not associated with differences in clinician-reported acute or late GU/GI toxicities (all P ≥ .05). Five-year grade ≥2 GU and grade ≥1 GI TFS was 61.1% and 73.7% for IMRT, respectively, and 70.7% and 75.3% for PBT, respectively; and 5-year grade ≥3 GU and GI TFS was >95% for both groups (all P ≥ .05). CONCLUSIONS: Postprostatectomy PBT minimized low-range bladder and rectal doses relative to IMRT; however, treatment modality was not associated with clinician-reported GU/GI toxicities. Future prospective investigation and ongoing follow-up will determine whether dosimetric differences between IMRT and PBT confer clinically meaningful differences in long-term outcomes.
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Neoplasias de la Próstata/radioterapia , Terapia de Protones/métodos , Radioterapia de Intensidad Modulada/métodos , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Neoplasias de la Próstata/patología , Estudios RetrospectivosRESUMEN
This study assesses career satisfaction, discrepancies between ideal and expected careers, and likelihood of leaving current positions among former K awardees.
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Braquiterapia , Terapia de Protones , Humanos , Masculino , Próstata , Prostatectomía , ProtonesRESUMEN
OBJECTIVES: The Hispanic/Latinx population has consistently faced disparities in oncology access and outcomes with cancer being the leading cause of death in this population. We evaluate recent research in radiation therapy disparities among the Hispanic/Latinx population in the United States since our seminal analysis from 2017. METHODS: A PubMed literature search was conducted for articles published from January 2017 through March 2023. Four term combinations were utilized, including: (1) "Hispanic" and "Radiotherapy" and "Disparities", (2) "Latino" and "Radiotherapy" and "Hispanic", (3) "Hispanic" and "Radiation" and "Disparities", and (4) "Latino" and "Radiation" and "Disparities." Included studies were those taking place in the United States, examined radiation oncology care, and examined health disparities. RESULTS: Fifty-eight of 245 articles returned met inclusion criteria and spanned 6 disparity-types: (1) Stage at Presentation, (2) Time to Treatment Initiation & Completion, (3) Receipt of Treatment and Guideline-Concordant Care, (4) Geography, (5) Clinical Trial Access and (6) Insurance Barriers and Treatment Center Type. The most common disparity was receipt of treatment and guideline-concordant care (n=39 studies), demonstrating that the Hispanic/Latinx population was less likely to receive guideline-concordant treatment or treatment at all. In additon, studies identified disparities in time to treatment and completion (n=12), geography (n=5), clinical trial access (n=3), and insurance and treatment center access (n=5). CONCLUSIONS: Disparities in radiotherapy access remain prominent for the Hispanic/Latinx population through a multitude of barriers, despite increasing interest in disparities research. Continued health care disparities research with tangible interventions are needed in radiation oncology to properly understand and address this problem.
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Disparidades en Atención de Salud , Oncología por Radiación , Humanos , Hispánicos o Latinos , Estados Unidos , Accesibilidad a los Servicios de SaludRESUMEN
Importance: For patients with nonspine bone metastases, short-course radiotherapy (RT) can reduce patient burden without sacrificing clinical benefit. However, there is great variation in uptake of short-course RT across practice settings. Objective: To evaluate whether a set of 3 implementation strategies facilitates increased adoption of a consensus recommendation to treat nonspine bone metastases with short-course RT (ie, ≤5 fractions). Design, Setting, and Participants: This prospective, stepped-wedge, cluster randomized quality improvement study was conducted at 3 community-based cancer centers within an existing academic-community partnership. Rollout was initiated in 3-month increments between October 2021 and May 2022. Participants included treating physicians and patients receiving RT for nonspine bone metastases. Data analysis was performed from October 2022 to May 2023. Exposures: Three implementation strategies-(1) dissemination of published consensus guidelines, (2) personalized audit-and-feedback reports, and (3) an email-based electronic consultation platform (eConsult)-were rolled out to physicians. Main Outcomes and Measures: The primary outcome was adherence to the consensus recommendation of short-course RT for nonspine bone metastases. Mixed-effects logistic regression at the bone metastasis level was used to model associations between the exposure of physicians to the set of strategies (preimplementation vs postimplementation) and short-course RT, while accounting for patient and physician characteristics and calendar time, with a random effect for physician. Physician surveys were administered before implementation and after implementation to assess feasibility, acceptability, and appropriateness of each strategy. Results: Forty-five physicians treated 714 patients (median [IQR] age at treatment start, 67 [59-75] years; 343 women [48%]) with 838 unique nonspine bone metastases during the study period. Implementing the set of strategies was not associated with use of short-course RT (odds ratio, 0.78; 95% CI, 0.45-1.34; P = .40), with unadjusted adherence rates of 53% (444 lesions) preimplementation vs 56% (469 lesions) postimplementation; however, the adjusted odds of adherence increased with calendar time (odds ratio, 1.68; 95% CI, 1.20-2.36; P = .003). All 3 implementation strategies were perceived as being feasible, acceptable, and appropriate; only the perception of audit-and-feedback appropriateness changed before vs after implementation (19 of 29 physicians [66%] vs 27 of 30 physicians [90%]; P = .03, Fisher exact test), with 20 physicians (67%) preferring reports quarterly. Conclusions and Relevance: In this quality improvement study, a multicomponent set of implementation strategies was not associated with increased use of short-course RT within an academic-community partnership. However, practice improved with time, perhaps owing to secular trends or physician awareness of the study. Audit-and-feedback was more appropriate than anticipated. Findings support the need to investigate optimal approaches for promoting evidence-based radiation practice across settings.
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Neoplasias Óseas , Mejoramiento de la Calidad , Humanos , Neoplasias Óseas/secundario , Neoplasias Óseas/radioterapia , Femenino , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Anciano , Adhesión a Directriz/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricosRESUMEN
Given its sharp dose fall off and ability to spare healthy surrounding tissue, proton beam therapy (PBT) has traditionally been used to treat various types of malignancies in the definitive setting, with strong, empirical data supporting its utility and safety. In the palliative setting, however, photon therapy has generally remained the standard of care in radiation treatment delivery due to lower cost, and greater availability. However, recent data suggest that the use of PBT may provide benefit in terms of symptom management and disease control in patients with locally advanced or recurrent disease who do not qualify for definitive therapy or with metastatic disease. Additionally, due to its unique dosimetric properties, PBT may confer less overall toxicity, thus helping preserve or improve the quality of life in this patient population, especially for those who are nearing end of life. While there is a need for further study, initial data analyzed from both retrospective and prospective single-institution and multi-institution trials are promising. This review aims to explore the efficacy and safety of PBT in the palliative setting among adults and to summarize pertinent studies that support its usage. To the authors' knowledge, this is the first review of the literature pertaining to PBT used in the palliative setting across multiple disease sites.
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Neoplasias , Terapia de Protones , Adulto , Humanos , Estudios Retrospectivos , Calidad de Vida , Estudios Prospectivos , Neoplasias/radioterapiaRESUMEN
ABSTRACT: This chapter will discuss (1) the rationale for physician workforce diversity and inclusion in oncology; (2) current and historical physician workforce demographic trends in oncology, including workforce data at various training and career levels, such as graduate medical education and as academic faculty or practicing physicians; (3) reported barriers and challenges to diversity and inclusion in oncology, such as exposure, access, preparation, mentorship, socioeconomic burdens, and interpersonal, structural, systemic bias; and (4) potential interventions and evidence-based solutions to increase diversity, equity, and inclusion and mitigate bias in the oncology physician workforce.
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Médicos , Humanos , Oncología Médica , Recursos HumanosRESUMEN
PURPOSE: Compared with conventional external-beam radiation therapy (cEBRT) for patients with breast cancer (BC) and prostate cancer (PC), shorter radiation regimens may be associated with lower treatment noncompletion rates. We assess disparities in receipt of shorter radiation regimens and treatment noncompletion for BC and PC. PATIENTS AND METHODS: The 2004-2017 National Cancer Database was queried for adjuvant cEBRT or hypofractionated EBRT (hEBRT) for nonmetastatic BC; and definitive cEBRT, moderate hypofractionation (mEBRT), or stereotactic body radiotherapy (SBRT) for localized PC. Multivariable logistic regression identified factors associated with treatment noncompletion and receipt of shorter regimens. FINDINGS: We identified 170,386 men with PC (median age [interquartile range], 70 [64-75] years; Black, 17.5%; White, 82.5%) and 306,846 women with BC (61 [52-69] years; Black, 12.3%; White, 87.7%). Among patients who received cEBRT for PC, Black men had higher treatment noncompletion rates compared with White (14.1% v 13.0%; odds ratio [95% CI] 1.07 [1.03 to 1.12]; P < .001). In contrast, treatment noncompletion was not disparate with SBRT (Black 1.6% v White 1.3%; 1.20 [0.72 to 2.00], P = .49) or mEBRT (Black 9.0% v White 7.1%; 1.05 [0.72 to 1.54], P = .79). From 2004 to 2017, SBRT (0.07% to 11.8%; 1.32 [1.31 to 1.33]) and mEBRT (0.35% to 9.1%; 1.27 [1.25 to 1.28]) increased (both P < .001); however, Black men were consistently less likely to receive SBRT (7.4% v White, 8.3%; 0.84 [0.79 to 0.89], P < .001). Among women with BC, there were no racial differences in treatment noncompletion; however, hEBRT was associated with lower treatment noncompletion rates (1.0% v cEBRT 2.3%; 0.39 [0.35 to 0.44], P < .001). Although hEBRT for BC increased (0.8% to 35.6%) between 2004 and 2017, Black women were less likely to receive hEBRT (10.4% v 15.3%; 0.78 [0.75 to 0.81], P < .001). INTERPRETATION: Black patients were consistently less likely to receive hypofractionated radiation for PC or BC, despite evidence suggesting that shorter regimens may lower rates of treatment noncompletion with similar oncologic outcomes.
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Neoplasias de la Mama , Neoplasias de la Próstata , Radiocirugia , Masculino , Humanos , Estados Unidos/epidemiología , Anciano , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/radioterapia , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Hipofraccionamiento de la Dosis de RadiaciónRESUMEN
There is a need to identify predictive biomarkers to guide treatment strategies in stage III non-small cell lung cancer (NSCLCs). In this multi-institutional cohort of 197 patients with stage III NSCLC treated with concurrent chemoradiation (cCRT) and durvalumab consolidation, we identify that low tumor aneuploidy is independently associated with prolonged progression-free survival (HR 0.63; p=0.03) and overall survival (HR 0.50; p=0.03). Tumors with high aneuploidy had a significantly greater incidence of distant metastasis and shorter median distant-metastasis free survival (p=0.04 and p=0.048, respectively), but aneuploidy level did not associate with local-regional outcomes. Multiplexed immunofluorescence analysis in a cohort of NSCLC found increased intratumoral CD8-positive, PD-1-positive cells, double-positive PD-1 CD8 cells, and FOXP3-positive T-cell in low aneuploid tumors. Additionally, in a cohort of 101 patients treated with cCRT alone, tumor aneuploidy did not associate with disease outcomes. These data support the need for upfront treatment intensification strategies in stage III NSCLC patients with high aneuploid tumors and suggest that tumor aneuploidy is a promising predictive biomarker.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Receptor de Muerte Celular Programada 1 , AneuploidiaRESUMEN
In the last 20 years, significant strides have been made in our understanding of the biological mechanisms driving disease pathogenesis in metastatic non-small cell lung cancer (NSCLC). Notably, the development and application of predictive biomarkers as well as refined treatment regimens in the form of chemoimmunotherapy and novel targeted agents have led to substantial improvements in survival. Parallel to these remarkable advancements in modern systemic therapy has been a growing recognition of "oligometastatic disease" as a distinct clinical entity-defined by the presence of a controlled primary tumor and ≤5 sites of metastatic disease amenable to local consolidative therapy (LAT), with surgery or stereotactic ablative body radiotherapy (SABR). To date, three randomized studies have provided clinical evidence supporting the use of LAT/SABR in the treatment of oligometastatic NSCLC. In this review, we summarize clinical evidence from these landmark studies and highlight ongoing trials evaluating the use of LAT/SABR in a variety of clinical contexts along the oligometastatic disease spectrum. We discuss important implications and caveats of the available data, including considerations surrounding patient selection and application in routine clinical practice. We conclude by offering potential avenues for further investigation in the oligometastatic disease space.
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This cross-sectional study uses data from the Centers for Medicare & Medicaid Services to assess the use of professional society guideline-nonconcordant radiotherapy in patients at the end of life.
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Medicare , Neoplasias , Anciano , Estudios Transversales , Muerte , Humanos , Estados Unidos/epidemiologíaRESUMEN
For patients with oligometastatic cancer, radiotherapy presents a promising avenue for achieving meaningful symptom relief and durable disease control. Data from recently published and ongoing randomized studies are helping to define the appropriate contexts for effective intervention with stereotactic ablative body radiotherapy (SABR) in the oligometastatic setting. Importantly, older adults represent a significant portion of patients with oligometastatic disease, yet often comprise a minority of patients in clinical trials. Moreover, older adults of the same chronologic age may have variable degrees of fitness and frailty. In this review, we highlight the specific challenges and considerations for the use of radiotherapy for older adults with oligometastatic disease-noting the importance of geriatric assessments in clinical decision-making about the appropriateness of SABR and other metastasis-directed therapies in this population. We then review data from existing trials, including a subset analysis of adverse events and survival estimates among older adults enrolled in the landmark SABR-COMET trial. Finally, we discuss future directions for research, including the need for focused clinical trials in older adult cohorts. Ultimately, a multidisciplinary approach is critical when carefully balancing the potential risks and benefits of this emerging treatment paradigm in the older adult population.
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Neoplasias , Radiocirugia , Anciano , Humanos , Neoplasias/patología , Neoplasias/radioterapia , Radiocirugia/efectos adversos , Radiocirugia/métodosRESUMEN
PURPOSE: We identified (1) differences in localized prostate cancer (PCa) risk group at presentation and (2) disparities in access to initial treatment for Asian American, Native Hawaiian, and Pacific Islander (AANHPI) men with PCa after controlling for sociodemographic factors. METHODS: We assessed all patients in the National Cancer Database with localized PCa with low-, intermediate-, and high-risk disease who identified as Thai, White, Asian Indian, Chinese, Vietnamese, Korean, Japanese, Filipino, Hawaiian, Pacific Islander, Laotian, Pakistani, Kampuchean, and Hmong. Multivariable logistic regression defined adjusted odds ratios (AORs) with 95% CI of (1) presenting at progressively higher risk group and (2) receiving treatment or active surveillance with intermediate- or high-risk disease, adjusting for sociodemographic and clinical factors. RESULTS: Among 980,889 men (median age 66 years), all AANHPI subgroups with the exception of Thai (AOR = 0.84 [95% CI, 0.58 to 1.21], P > .05), Asian Indian (AOR = 1.12 [95% CI, 1.00 to 1.25], P > .05), and Pakistani (AOR = 1.34 [95% CI, 0.98 to 1.83], P > .05) men had greater odds of presenting at a progressively higher PCa risk group compared with White patients (Chinese AOR = 1.18 [95% CI, 1.11 to 1.25], P < .001; Japanese AOR = 1.36 [95% CI, 1.26 to 1.47], P < .001; Filipino AOR = 1.37 [95% CI, 1.29 to 1.46], P < .001; Korean AOR = 1.32 [95% CI, 1.18 to 1.48], P < .001; Vietnamese AOR = 1.20 [95% CI, 1.07 to 1.35], P = .002; Laotian AOR = 1.60 [95% CI, 1.08 to 2.36], P = .018; Hmong AOR = 4.07 [95% CI, 1.54 to 10.81], P = .005; Kampuchean AOR = 1.55 [95% CI, 1.03 to 2.34], P = .036; Asian Indian or Pakistani AOR = 1.15 [95% CI, 1.07 to 1.24], P < .001; Native Hawaiians AOR = 1.58 [95% CI, 1.38 to 1.80], P < .001; and Pacific Islanders AOR = 1.58 [95% CI, 1.37 to 1.82], P < .001). Additionally, Japanese Americans (AOR = 1.46 [95% CI, 1.09 to 1.97], P = .013) were more likely to receive treatment compared with White patients. CONCLUSION: Our findings suggest that there are differences in PCa risk group at presentation by race or ethnicity among Asian American, Native Hawaiian, and Pacific Islander subgroups and that there exist disparities in treatment patterns. Although AANHPI are often studied as a homogenous group, heterogeneity upon subgroup disaggregation underscores the importance of further study to assess and address barriers to PCa care.
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Asiático , Neoplasias de la Próstata , Anciano , Etnicidad , Hawaii/epidemiología , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Nativos de Hawái y Otras Islas del Pacífico , Neoplasias de la Próstata/terapia , Factores SociodemográficosRESUMEN
PURPOSE: Guidelines recommend short-course (≤10 fractions) external-beam radiation therapy (EBRT) for bone metastases. Stereotactic body radiation therapy (SBRT) may also improve outcomes; however, routine use is not recommended outside clinical trials. We assessed national radiation therapy trends in complex techniques for bone metastases and associated expenditures. METHODS AND MATERIALS: Using a claims-based Medicare data set covering 84% of beneficiaries, we assessed the relative proportion of all radiation episodes represented by bone metastases. We then evaluated use of short-course and long-course (>10 fractions) EBRT, intensity modulated radiation therapy (IMRT), and SBRT for bone metastases in hospital-affiliated outpatient (OPD) or freestanding (FREE) facilities. We assessed differences using χ2d or Wilcoxon rank sum tests for categorical and continuous variables, respectively. We identified associations with modality, fractionation, and expenditures using multivariable logistic/linear regression. RESULTS: Among 467,781 radiation episodes for 17 cancer diagnoses, the overall proportion of episodes dedicated to bone metastases (9.4%) was stable from 2015 to 2017, although treatments were increasing in the hospital-affiliated outpatient setting (P < .005). We identified 40,993 episodes for bone metastases, of which 63% were short-course EBRT, 24% were long-course EBRT, 7% were SBRT, and 6% were IMRT. Techniques more common in the hospital-affiliated outpatient setting included short-course EBRT (OPD, 69%, vs FREE, 56%) and SBRT (OPD, 9%, vs FREE, 5%). Techniques more common among free-standing centers included long-course EBRT (OPD, 19%, vs FREE, 31%) and IMRT (OPD, 4%, vs FREE, 9%). From 2015 to 2017, long-course EBRT decreased by an absolute 8%; short-course EBRT, SBRT, and IMRT increased by 4%, 2.5%, and 1%, respectively. The SBRT/IMRT uptake did not differ by setting (P = .4). Differences in expenditures between SBRT and short-course EBRT decreased by a relative 8% in professional and 12% in technical fees. CONCLUSIONS: Approximately 1 in 4 patients received long-course EBRT, with small reductions in use largely replaced by complex treatment modalities. However, expenditures for complex modalities also decreased over time. As alternative payment models take effect, quality metrics are needed to ensure appropriate, effective, and safe delivery of complex technologies.
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Neoplasias Óseas/radioterapia , Neoplasias Óseas/secundario , Radiocirugia/tendencias , Radioterapia de Intensidad Modulada/tendencias , Anciano , Anciano de 80 o más Años , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , MasculinoRESUMEN
PURPOSE: Treatment noncompletion may occur with radiation therapy (RT), especially with protracted treatment courses such as RT for prostate cancer, and may affect the efficacy of RT. For men with localized prostate cancer managed with primary RT, we evaluated associations between rates of treatment noncompletion and RT fractionation schedules. METHODS AND MATERIALS: The National Cancer Database identified men diagnosed from 2004 to 2014 treated with primary RT. Patients receiving 180 cGy/fraction or 200 cGy/fraction were defined as having completed radiation therapy if they received ≥41 fractions of 180 cGy/fraction or ≥37 fractions of 200 cGy/fraction. Stereotactic body radiation therapy (SBRT) was defined as 5 to 8 fractions of 600 to 800 cGy/fraction. Odds ratios compared rates of treatment noncompletion, adjusting for sociodemographic covariates. A propensity-adjusted multivariable Cox regression assessed the association between treatment completion and overall survival. RESULTS: Of 157,657 patients, 95.7% (n = 150,847) received conventional fractionation and 4.3% (n = 6810) received SBRT. Rates of noncompletion were 12.5% (n = 18,803) among patients who received conventional fractionation and 1.9% (n = 131) among patients who received SBRT (odds ratio [OR] versus conventional, 0.21; 95% confidence interval [CI], 0.18-0.26; P < .001). The rate of noncompletion among 25,727 African American patients was 12.8%, compared with 11.8% among 126,199 white patients (OR, 1.14; 95% CI, 1.09-1.19; P < .001). In a subgroup analysis, the disparity in noncompletion persisted for conventional fractionation (13.2% vs 12.3%, respectively; OR, 1.09; 95% CI, 1.05-1.13; P < .001), but not for SBRT (2.2% vs 1.8%, respectively; OR, 1.26; 95% CI, 0.79-2.00; P = .34). Noncompletion was associated with worse survival in a propensity-adjusted multivariable analysis (hazard ratio, 1.25; 95% CI, 1.22-1.29; P < .001). CONCLUSIONS: SBRT was associated with lower rates of RT noncompletion among men with localized prostate cancer. African American race was associated with greater rates of treatment noncompletion, although the disparity may be decreased among men receiving SBRT.