RESUMEN
Mutations accumulate in the genome of every cell of the body throughout life, causing cancer and other diseases1,2. Most mutations begin as nucleotide mismatches or damage in one of the two strands of the DNA before becoming double-strand mutations if unrepaired or misrepaired3,4. However, current DNA-sequencing technologies cannot accurately resolve these initial single-strand events. Here we develop a single-molecule, long-read sequencing method (Hairpin Duplex Enhanced Fidelity sequencing (HiDEF-seq)) that achieves single-molecule fidelity for base substitutions when present in either one or both DNA strands. HiDEF-seq also detects cytosine deamination-a common type of DNA damage-with single-molecule fidelity. We profiled 134 samples from diverse tissues, including from individuals with cancer predisposition syndromes, and derive from them single-strand mismatch and damage signatures. We find correspondences between these single-strand signatures and known double-strand mutational signatures, which resolves the identity of the initiating lesions. Tumours deficient in both mismatch repair and replicative polymerase proofreading show distinct single-strand mismatch patterns compared to samples that are deficient in only polymerase proofreading. We also define a single-strand damage signature for APOBEC3A. In the mitochondrial genome, our findings support a mutagenic mechanism occurring primarily during replication. As double-strand DNA mutations are only the end point of the mutation process, our approach to detect the initiating single-strand events at single-molecule resolution will enable studies of how mutations arise in a variety of contexts, especially in cancer and ageing.
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Disparidad de Par Base , Daño del ADN , ADN de Cadena Simple , Análisis de Secuencia de ADN , Imagen Individual de Molécula , Humanos , Envejecimiento/genética , Desaminasas APOBEC/genética , Desaminasas APOBEC/metabolismo , Disparidad de Par Base/genética , Citidina Desaminasa/metabolismo , Citidina Desaminasa/genética , Citosina/metabolismo , Desaminación , Daño del ADN/genética , Reparación de la Incompatibilidad de ADN/genética , Replicación del ADN/genética , ADN de Cadena Simple/genética , Genoma Mitocondrial/genética , Mutación , Neoplasias/genética , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de ADN/normas , Imagen Individual de Molécula/métodos , Masculino , FemeninoRESUMEN
CONTEXT: In the United States (US) men who undergo vasectomy and/or vasectomy reversal (vasovasotomy) are likely to pay out-of-pocket for these procedures. We characterized the publicly disclosed pricing of both procedures with a focus on variability in self-pay prices. METHODS: We queried all US hospitals for publicly disclosed prices of vasectomy and vasovasotomy. We assessed interhospital variability in self-pay pricing and compared hospitals charging high (≥75th percentile) and low (≤25th percentile) self-pay prices for either procedure. We also examined trends in pricing after the 2022 US Supreme Court decision that allowed individual states to ban abortion. RESULTS: Of 6692 hospitals, 1375 (20.5%) and 281 (4.2%) disclosed self-pay prices for vasectomy and vasovasotomy, respectively. There was a 17-fold difference between the 10th and 90th percentile self-pay prices for vasectomy ($421-$7147) and a 39-fold difference for vasovasotomy ($446-$17,249). Compared with hospitals charging low (≤25th percentile) self-pay prices for vasectomy or vasovasotomy, hospitals charging high (≥75th percentile) prices were larger (median 150 vs. 59 beds, p < 0.001) and more likely to be for-profit (31.2% vs. 7.8%, p < 0.001), academic-affiliated (52.7% vs. 23.1%, p < 0.001), and located in an urban zip code (70.1% vs. 41.3%, p < 0.001). From October 2022 to April 2023, the median self-pay price of vasectomy increased by 10% (from $1667 to $1832) while the median self-pay price of vasovasotomy decreased by 16% (from $3309 to $2786). CONCLUSION: We found large variability in self-pay pricing for vasectomy and vasectomy reversal, which may serve as a barrier to the accessibility of male reproductive care.
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Vasectomía , Vasovasostomía , Humanos , Vasectomía/economía , Vasectomía/estadística & datos numéricos , Estados Unidos , Masculino , Vasovasostomía/economía , Financiación Personal/estadística & datos numéricosRESUMEN
BACKGROUND AND OBJECTIVE: Hypogonadism and frailty may impact postoperative outcomes for men undergoing radical nephrectomy (RN). We aimed to determine the prevalence of hypogonadism in men undergoing RN and whether hypogonadism and frailty are associated with adverse postoperative outcomes. METHODS: We identified men undergoing RN between 2012 and 2021 using the IBM Marketscan database. Frailty was determined using the Hospital Frailty Risk Score (HFRS). Patients were considered to have hypogonadism if diagnosed <5 years before RN. Length of stay (LOS), complications, emergency department (ED) visits, and readmissions were evaluated between men with and without hypogonadism at the time of surgery. Subgroup analysis of men with hypogonadism was performed to determine the effect of testosterone replacement therapy (TRT) on clinical outcomes. RESULTS: Among 13 598 men who underwent RN, 972 (7.1%) had hypogonadism. Men with hypogonadism were more frail compared to men without hypogonadism (HFRS: median: 8.2, interquartile range [IQR]: 5.2-11.7 vs. median: 7.0, IQR: 4.3-10.7, p < 0.001) and had increased incidence of postoperative ileus (13.0% vs. 10.8%, p = 0.045), acute kidney injury (25.5% vs. 21.6% p = 0.005), and cardiac arrest (1.2% vs. 0.6%, p = 0.034). Hypogonadism was not associated with LOS, 90-day ED visit or readmission. However, high-risk frailty was associated with increased risk of 90-day ED visit (hazard ratio [HR]: 2.1, 95% confidence interval [95% CI]: 1.9-2.4, p < 0.001) and 90-day inpatient readmission (HR: 2.6, 95% CI: 2.2-3.1, p < 0.001), compared to low-risk frailty patients. Among men with hypogonadism, TRT was not associated with any postoperative outcomes. CONCLUSIONS: Hypogonadism and frailty should be considered in the preoperative evaluation for men undergoing RN as risk factors for adverse postoperative outcomes.
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Fragilidad , Hipogonadismo , Nefrectomía , Complicaciones Posoperatorias , Humanos , Masculino , Hipogonadismo/epidemiología , Fragilidad/epidemiología , Fragilidad/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Persona de Mediana Edad , Nefrectomía/efectos adversos , Anciano , Neoplasias Renales/cirugía , Estudios de Seguimiento , Estudios Retrospectivos , Tiempo de Internación/estadística & datos numéricos , Testosterona/uso terapéutico , Pronóstico , Factores de RiesgoRESUMEN
OBJECTIVE: To determine the prevalence and severity of SpaceOAR-related adverse events using the Manufacturer and User Facility Device Experience (MAUDE) database. METHODS: We analyzed SpaceOAR-related adverse event reports in the Manufacturer and User Facility Device Experience (MAUDE) database from January 2015 to May 2023. For each report, the event type, associated device and patient problems, event description, event timing, and event severity stratified by the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE) grading system were recorded. RESULTS: From 2015 to 2022, 206,619 SpaceOAR devices were sold. From January 2015 to May 2023, we identified 981 reports describing 990 SpaceOAR-related adverse events. Malfunctions were the most common event type (N = 626), followed by patient injuries (N = 350) with few reported deaths (N = 5). Device positioning problems were the most frequent device issue (N = 686). Pain was the most reported patient problem (N = 216). Abscesses and fistulas related to the device were each reported in 91 events. A noteworthy portion of relevant adverse events occurred before the initiation of radiation (N = 35, 22.4%), suggesting the device, rather than the radiation, was responsible. In total, 470 (50.2%) and 344 (36.7%) of the adverse events were CTCAE grade 1 and 2, respectively. There were 123 (13.1%) events that were CTCAE grade ≥3. CONCLUSION: We identified multiple reports of SpaceOAR-related adverse events, many of which are more serious than have been reported in clinical trials. While SpaceOAR use is common, suggesting these events are rare, these data highlight the need for continued postmarket surveillance.
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Hidrogeles , Neoplasias de la Próstata , Humanos , Neoplasias de la Próstata/radioterapia , Masculino , Hidrogeles/efectos adversos , Falla de Equipo/estadística & datos numéricosRESUMEN
BACKGROUND. PI-RADS incorporates rules by which ancillary sequence findings upgrade a dominant score to a higher final category. Evidence on the upgrading rules' impact on diagnostic pathways remains scarce. OBJECTIVE. The purpose of this article was to evaluate the clinical net benefit of the PI-RADS upgrading rules in MRI-directed diagnostic pathways. METHODS. This study was a retrospective analysis of a prospectively maintained clinical registry. The study included patients without known prostate cancer who underwent prostate MRI followed by prostate biopsy from January 2016 to May 2020. Clinically significant prostate cancer (csPCa) was defined as International Society of Urological Pathology (ISUP) grade group 2 and higher. csPCa detection was compared between dominant (i.e., no upgrade rule applied) and upgraded lesions. Decision-curve analysis was used to compare the net benefit, considering the trade-off of csPCa detection and biopsy avoidance, of MRI-directed pathways in scenarios considering and disregarding PI-RADS upgrading rules. These included a biopsy-all pathway, MRI-focused pathway (no biopsy for PI-RADS ≤ 2), and risk-based pathway (use of PSA density ≥ 0.15 ng/mL2 to select patients with PI-RADS ≤ 3 for biopsy). RESULTS. The sample comprised 716 patients (mean age, 64.9 years; 93 with a PI-RADS ≤ 2 examination, 623 with total of 780 PI-RADS ≥ 3 lesions). Frequencies of csPCa were not significantly different between dominant and upgraded PI-RADS 3 transition zone lesions (20% vs 19%, respectively), dominant and upgraded PI-RADS 4 transition zone lesions (33% vs 26%), and dominant and upgraded PI-RADS 4 peripheral zone lesions (58% vs 45%) (p > .05). In the biopsy-all, per-guideline MRI-focused, MRI-focused disregarding upgrading rules, per-guideline risk-based, and risk-based disregarding upgrading rules pathways, csPCa frequency was 53%, 52%, 51%, 52%, and 48% and biopsy avoidance was 0%, 13%, 16%, 19%, and 25%, respectively. Disregarding upgrading rules yielded 5.5 and 1.9 biopsies avoided per missed csPCa for MRI-focused and risk-based pathways, respectively. At probability thresholds for biopsy selection of 7.5-30.0%, net benefit was highest for the per-guideline risk-based pathway. CONCLUSION. Disregarding PI-RADS upgrading rules reduced net clinical bene fit of the risk-based MRI-directed diagnostic pathway when considering trade-offs between csPCa detection and biopsy avoidance. CLINICAL IMPACT. This study supports the application of PI-RADS upgrading rules to optimize biopsy selection, particularly in risk-based pathways.
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Imagen por Resonancia Magnética , Neoplasias de la Próstata , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Masculino , Imagen por Resonancia Magnética/métodos , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Biopsia Guiada por Imagen/métodos , Clasificación del Tumor , Reglas de Decisión ClínicaRESUMEN
PURPOSE: To better understand the effects of aging, metabolic syndrome, diurnal variation, and seasonal variation on serum testosterone levels in the context of current guideline statements on testosterone deficiency. METHODS: This cross-sectional study utilized the United Kingdom Biobank. Physical examination, anthropomorphic measurements, and laboratory evaluation were performed at the time of enrollment from 2006 to 2010. The primary outcomes were the effect of age, the presence of metabolic syndrome, the time of day, and the month of the year on serum testosterone levels. RESULTS: Among 197,883 included men, the 5th, 25th, 50th, 75th and 95th percentile testosterone levels in men without metabolic syndrome were significantly higher than those in men with metabolic syndrome at every decade of life (p < 0.001). The average testosterone level within each group (men without metabolic syndrome vs. men with) was clinically similar across decade of life (12.43 in 40's 12.29 in 50's 12.24 in 60's vs. 10.69 in 40's 10.56 in 50's 10.63 in 60's respectively). Average testosterone levels decreased with blood draws later in the day ranging from 10.91 to 12.74 nmol/L (p < 0.01). Similarly, there was seasonal variation in serum testosterone ranging from 11.86 to 12.18 nmol/L (p < 0.01). CONCLUSIONS: We found significant variation in serum testosterone according to the presence of metabolic syndrome and time of laboratory draw, but not according to age. These data challenge the prior dogma of age-related hypogonadism and favor an individualized approach towards serum testosterone measurement and interpretation. However, further studies are needed to correlate these population-based data with individuals' hypogonadal symptoms.
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INTRODUCTION: Hypogonadism is associated with frailty, lower health-related quality of life, decreased muscle mass, and premature mortality, which may predispose patients to poor postoperative outcomes. We aimed to determine the prevalence of hypogonadism in men undergoing radical cystectomy (RC) and whether hypogonadism and frailty are associated with adverse postoperative outcomes. MATERIALS AND METHODS: The IBM MarketScan database was used to identify men who underwent RC between 2012 and 2021. Frailty was determined using published Hospital Frailty Risk Score ranges. Patients were considered to have hypogonadism if diagnosed within 5 years prior to RC. Length of stay (LOS), complications, emergency department (ED) visits and inpatient readmissions were compared. Sub-group analysis of men with hypogonadism was performed to determine the effect of testosterone replacement therapy (TRT) on clinical outcomes. RESULTS: Among 3,727 men who underwent RC, 226 (6.1%) had a diagnosis of hypogonadism. Overall, 565 (15.2%) men were low-risk frailty, 2,214 (59.4%) intermediate-risk frailty, and 948 (25.4%) were high-risk frailty, and men with hypogonadism were significantly more frail compared to men without hypogonadism (Pâ¯=â¯0.027). There was no significant difference in LOS, complications, or rate of ED visits and inpatient readmissions between cohorts (P > 0.05). However, high-risk frailty was associated with an increased risk of 90-day ED visit (HR 1.19, 95%CI 1.00-1.41, Pâ¯=â¯0.049) and 90-day readmission (HR 1.60, 95%CI 1.29-1.97, P < 0.001) after RC. Among men with hypogonadism, 58 (25.7%) were on TRT. There was no significant difference in frailty, LOS, complications, or 90-day ED visits or 90-day inpatient readmissions between patient with hypogonadism prescribed TRT and those without TRT. CONCLUSIONS: These findings suggest that hypogonadism and preoperative frailty may be important to evaluate prior to undergoing RC.
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Fragilidad , Hipogonadismo , Neoplasias de la Vejiga Urinaria , Masculino , Humanos , Femenino , Fragilidad/complicaciones , Fragilidad/diagnóstico , Cistectomía/efectos adversos , Calidad de Vida , Neoplasias de la Vejiga Urinaria/complicaciones , Neoplasias de la Vejiga Urinaria/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Tiempo de Internación , Hipogonadismo/complicaciones , Estudios RetrospectivosRESUMEN
BACKGROUND AND OBJECTIVE: The transrectal biopsy approach is traditionally used to detect prostate cancer. An alternative transperineal approach is historically performed under general anesthesia, but recent advances enable transperineal biopsy to be performed under local anesthesia. We sought to compare infectious complications of transperineal biopsy without antibiotic prophylaxis versus transrectal biopsy with targeted prophylaxis. METHODS: We assigned biopsy-naïve participants to undergo transperineal biopsy without antibiotic prophylaxis versus transrectal biopsy with targeted prophylaxis (rectal culture screening for fluoroquinolone-resistant bacteria and antibiotic targeting to culture and sensitivity results) through a multicenter, randomized trial. The primary outcome was post-biopsy infection captured by a prospective medical review and patient report on a 7-d survey. The secondary outcomes included cancer detection, noninfectious complications, and a numerical rating scale (0-10) for biopsy-related pain and discomfort during and 7-d after biopsy. KEY FINDINGS AND LIMITATIONS: A total of 658 participants were randomized, with zero transperineal versus four (1.4%) transrectal biopsy infections (difference -1.4%; 95% confidence interval [CI] -3.2%, 0.3%; p = 0.059). The rates of other complications were very low and similar. Importantly, detection of clinically significant cancer was similar (53% transperineal vs 50% transrectal, adjusted difference 2.0%; 95% CI -6.0, 10). Participants in the transperineal arm experienced worse periprocedural pain (0.6 adjusted difference [0-10 scale], 95% CI 0.2, 0.9), but the effect was small and resolved by 7-d. CONCLUSIONS AND CLINICAL IMPLICATIONS: Office-based transperineal biopsy is tolerable, does not compromise cancer detection, and did not result in infectious complications. Transrectal biopsy with targeted prophylaxis achieved similar infection rates, but requires rectal cultures and careful attention to antibiotic selection and administration. Consideration of these factors and antibiotic stewardship should guide clinical decision-making. PATIENT SUMMARY: In this multicenter randomized trial, we compare prostate biopsy infectious complications for the transperineal versus transrectal approach. The absence of infectious complications with transperineal biopsy without the use of preventative antibiotics is noteworthy, but not significantly different from transrectal biopsy with targeted antibiotic prophylaxis.
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Profilaxis Antibiótica , Biopsia Guiada por Imagen , Perineo , Próstata , Neoplasias de la Próstata , Recto , Humanos , Masculino , Biopsia Guiada por Imagen/métodos , Biopsia Guiada por Imagen/efectos adversos , Anciano , Profilaxis Antibiótica/métodos , Persona de Mediana Edad , Recto/microbiología , Próstata/patología , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética Intervencional , Estudios ProspectivosAsunto(s)
Próstata , Procedimientos Quirúrgicos Robotizados , Masculino , Humanos , Próstata/cirugía , ProstatectomíaRESUMEN
Artificial intelligence (AI) applications have enabled remarkable advancements in healthcare delivery. These AI tools are often aimed to improve accuracy and efficiency of histopathology assessment and diagnostic imaging interpretation, risk stratification (i.e., prognostication), and prediction of therapeutic benefit for personalized treatment recommendations. To date, multiple AI algorithms have been explored for prostate cancer to address automation of clinical workflow, integration of data from multiple domains in the decision-making process, and the generation of diagnostic, prognostic, and predictive biomarkers. While many studies remain within the pre-clinical space or lack validation, the last few years have witnessed the emergence of robust AI-based biomarkers validated on thousands of patients, and the prospective deployment of clinically-integrated workflows for automated radiation therapy design. To advance the field forward, multi-institutional and multi-disciplinary collaborations are needed in order to prospectively implement interoperable and accountable AI technology routinely in clinic.
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Inteligencia Artificial , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia , Estudios Prospectivos , Algoritmos , BiomarcadoresRESUMEN
BACKGROUND: The FDA issued a "black box" warning regarding risks of fluoroquinolones in 2008 with updates in 2011, 2013, and 2016. OBJECTIVE: To examine antimicrobial use in hospital-treated UTIs from 2000 to 2020. DESIGN: Cross-sectional study with interrupted time series analysis. PARTICIPANTS: Patient encounters with a diagnosis of UTI from January 2000 to March 2020, excluding diagnoses of renal abscess, chronic cystitis, and infection of the gastrointestinal tract, lungs, or prostate. MAIN MEASURES: Monthly use of fluoroquinolone and non-fluoroquinolone antibiotics were assessed. Fluoroquinolone resistance was assessed in available cultures. Interrupted time series analysis examined level and trend changes of antimicrobial use with each FDA label change. KEY RESULTS: A total of 9,950,790 patient encounters were included. From July 2008 to March 2020, fluoroquinolone use declined from 61.7% to 11.7%, with similar negative trends observed in inpatients and outpatients, age ≥ 60 and < 60 years, males and females, patients with and without pyelonephritis, and across physician specialties. Ceftriaxone use increased from 26.4% encounters in July 2008 to 63.6% of encounters in March 2020. Among encounters with available culture data, fluoroquinolone resistance declined by 28.9% from 2009 to 2020. On interrupted time series analysis, the July 2008 FDA warning was associated with a trend change (-0.32%, < 0.001) and level change (-5.02%, p < 0.001) in monthly fluoroquinolone use. CONCLUSIONS: During this era of "black box" warnings, there was a decline in fluoroquinolone use for hospital-treated UTI with a concomitant decline in fluoroquinolone resistance and rise in ceftriaxone use. Efforts to restrict use of a medication class may lead to compensatory increases in use of a single alternative agent with changes in antimicrobial resistance profiles.
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Antibacterianos , United States Food and Drug Administration , Infecciones Urinarias , Humanos , Infecciones Urinarias/tratamiento farmacológico , Masculino , Femenino , Estados Unidos/epidemiología , Estudios Transversales , Antibacterianos/uso terapéutico , Antibacterianos/efectos adversos , Persona de Mediana Edad , Anciano , Adulto , Fluoroquinolonas/uso terapéutico , Análisis de Series de Tiempo Interrumpido , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiologíaRESUMEN
Renal cell carcinoma (RCC), especially clear cell RCC, is generally considered an immunotherapy-responsive cancer. Recently, the prognosis for patients with locally advanced and metastatic RCC has significantly improved with the regulatory approvals of anti-PD-1/PD-L1/CTLA-4 immune checkpoint inhibitor (ICI)-based regimens. Yet in most cases, RCC will remain initially unresponsive to treatment or will develop resistance over time. Hence, there remains an unmet need to understand what leads to ICI resistance and to develop novel immune and nonimmune treatments to enhance the response to ICIs. In this review, we highlight recently published studies and the latest clinical studies investigating the next generation of immune approaches to locally advanced and metastatic RCC beyond traditional ICIs. These trials include cytokines, gut microbiota-based therapies, novel immune checkpoint agents, vaccines, and chimeric antigen receptor T cells. These agents are being evaluated as monotherapy or in combination with traditional ICIs and will hopefully provide improved outcomes to patients with RCC soon.
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Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/terapia , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Pronóstico , Inmunoterapia , Neoplasias Renales/terapiaRESUMEN
To investigate the relative contributions of natural history and clinical interventions to racial disparities in prostate cancer mortality in the United States, we extended a model that was previously calibrated to Surveillance, Epidemiology, and End Results (SEER) incidence rates for the general population and for Black men. The extended model integrated SEER data on curative treatment frequencies and cancer-specific survival. Starting with the model for all men, we replaced up to 9 components with corresponding components for Black men, projecting age-standardized mortality rates for ages 40-84 years at each step. Based on projections in 2019, the increased frequency of developing disease, more aggressive tumor features, and worse cancer-specific survival in Black men diagnosed at local-regional and distant stages explained 38%, 34%, 22%, and 8% of the modeled disparity in mortality. Our results point to intensified screening and improved care in Black men as priority areas to achieve greater equity.
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Negro o Afroamericano , Disparidades en el Estado de Salud , Neoplasias de la Próstata , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/terapia , Programa de VERF , Estados Unidos/epidemiología , BlancoRESUMEN
Importance: Randomized clinical trials have demonstrated the noninferiority of shorter radiotherapy (RT) courses (termed hypofractionation) compared with longer RT courses in patients with localized prostate cancer. Although shorter courses are associated with cost-effectiveness, convenience, and expanded RT access, their adoption remains variable. Objective: To identify the current practice patterns of external beam RT for prostate cancer in the US. Design, Setting, and Participants: This cohort study obtained data from the National Cancer Database, which collects hospital registry data from more than 1500 accredited US facilities on approximately 72% of US patients with cancer. Patients were included in the sample if they had localized prostate adenocarcinoma that was diagnosed between 2004 and 2020 and underwent external beam RT with curative intent. Analyses were conducted between February and March 2023. Exposures: Radiotherapy schedules, which were categorized as ultrahypofractionation (≤7 fractions), moderate hypofractionation (20-30 fractions), and conventional fractionation (31-50 fractions). Main Outcomes and Measures: Longitudinal pattern in RT fractionation schedule was the primary outcome. Multivariable logistic regression was performed to evaluate the variables associated with shorter RT courses. Covariables included age, National Comprehensive Cancer Network risk group, rurality, race, facility location, facility type, median income, insurance type or status, and Charlson-Deyo Comorbidity Index. Results: A total of 313 062 patients with localized prostate cancer (mean [SD] age, 68.8 [7.7] years) were included in the analysis. There was a temporal pattern of decline in the proportion of patients who received conventional fractionation, from 76.0% in 2004 to 36.6% in 2020 (P for trend <.001). From 2004 to 2020, use of moderate hypofractionation increased from 22.0% to 45.0% (P for trend <.001), and use of ultrahypofractionation increased from 2.0% to 18.3% (P for trend <.001). By 2020, the most common RT schedule was ultrahypofractionation for patients in the low-risk group and moderate hypofractionation for patients in the intermediate-risk group. On multivariable analysis, treatment at a community cancer program (compared with academic or research program; odds ratio [OR], 0.54 [95% CI, 0.52-0.56]; P < .001), Medicaid insurance (compared with Medicare; OR, 1.49 [95% CI, 1.41-1.57]; P < .001), Black race (compared with White race; OR, 0.90 [95% CI, 0.87-0.92]; P < .001), and higher median income (compared with lower median income; OR, 1.28 [95% CI, 1.25-1.31]; P < .001) were associated with receipt of shorter courses of RT. Conclusions and Relevance: Results of this cohort study showed an increase in the use of shorter courses of RT for prostate cancer from 2004 to 2020; a number of social determinants of health appeared to be associated with reduced adoption of shorter treatment courses. Realignment of reimbursement models may be necessary to enable broader adoption of ultrahypofractionation to support technology acquisition costs.