Capacidad de los antiandrógenos de nueva generación en disminuir el antígeno prostático específico en pacientes con cáncer de próstata metastásico
| dc.contributor.advisor | Villareal Trujillo, Nicolas | |
| dc.contributor.advisor | Camacho López, Paul Anthony | |
| dc.contributor.apolounab | Camacho López, Paul Anthony [paul-anthony-camacho-lópez] | spa |
| dc.contributor.author | Tarazona Jiménez, Pamela Alejandra | |
| dc.contributor.cvlac | Villareal Trujillo, Nicolas [0001691724] | spa |
| dc.contributor.cvlac | Camacho López, Paul Anthony [0000323578] | spa |
| dc.contributor.googlescholar | Camacho López, Paul Anthony [es&oi=ao] | spa |
| dc.contributor.orcid | Villareal Trujillo, Nicolas [0000-0002-5974-8035] | spa |
| dc.contributor.orcid | Camacho López, Paul Anthony [0000-0002-6233-9582] | spa |
| dc.contributor.orcid | Tarazona Jiménez, Pamela Alejandra [0000-0003-3077-5723] | spa |
| dc.coverage.campus | UNAB Campus Bucaramanga | spa |
| dc.coverage.spatial | Floridablanca (Santander, Colombia) | spa |
| dc.date.accessioned | 2026-03-13T15:54:19Z | |
| dc.date.available | 2026-03-13T15:54:19Z | |
| dc.date.issued | 2026-03-05 | |
| dc.degree.name | Especialista en Urología | spa |
| dc.description.abstract | El manejo del cáncer de próstata metastásico ha evolucionado de forma acelerada en los últimos años, siendo el bloqueo hormonal intensificado, la piedra angular del tratamiento. La adición de nuevas moléculas ARPI (Androgen Receptor Pathway Inhibitor en inglés) como: Enzalutamida, Abiraterona, Apalutamida y Darolutamida han mejorado todos los desenlaces oncológicos, especialmente la supervivencia global, supervivencia libre de progresión y control del dolor. El antígeno prostático específico (PSA) es el biomarcador de elección para el diagnóstico, seguimiento y pronóstico del cáncer de próstata. La respuesta profunda del PSA, definido como un valor de PSA menor a 0,2 ng/ml medido a los 6 meses del inicio del tratamiento se ha convertido en un excelente indicador de éxito del tratamiento y se ha correlacionado fuertemente en múltiples estudios con el pronóstico de la enfermedad. El objetivo de este estudio es caracterizar la respuesta profunda del PSA en pacientes con cáncer de próstata metastásico tanto sensibles como resistentes a la castración, que reciben terapia hormonal de nueva generación en un centro de referencia Colombiano. | spa |
| dc.description.abstractenglish | The management of metastatic prostate cancer has evolved rapidly in recent years, with intensified hormonal blockade serving as the cornerstone of treatment. The addition of new ARPI (Androgen Receptor Pathway Inhibitor) molecules—such as Enzalutamide, Abiraterone, Apalutamide, and Darolutamide—has improved all oncological outcomes, particularly overall survival, progression-free survival, and pain control. Prostate-specific antigen (PSA) is the biomarker of choice for the diagnosis, monitoring, and prognosis of prostate cancer. A deep PSA response, defined as a PSA value of less than 0.2 ng/ml measured 6 months after starting treatment, has become an excellent indicator of therapeutic success and has been strongly correlated in multiple studies with disease prognosis. | spa |
| dc.description.degreelevel | Especialización | spa |
| dc.description.learningmodality | Modalidad Presencial | spa |
| dc.description.tableofcontents | LISTA DE TABLAS .......................................................................................... 5 RESUMEN ....................................................................................................... 6 1. INTRODUCCIÓN ......................................................................................... 8 2. JUSTIFICACIÓN ......................................................................................... 10 3. MARCO TEÓRICO ......................................................................................12 4. ESTADO DEL ARTE ...................................................................................16 5. PREGUNTA DE INVESTIGACIÓN ..........................................................…17 6. OBJETIVOS ................................................................................................18 6.1. OBJETIVO GENERAL .............................................................................18 6.2. OBJETIVOS ESPECÍFICOS ....................................................................18 7. METODOLOGÍA .........................................................................................19 7.1. TIPO DE ESTUDIO ..................................................................................19 7.2. POBLACIÓN Y MUESTRA .....................................................................21 7.3. CRITERIOS DE INCLUSIÓN Y EXCLUSIÓN .........................................21 7.4. RECOLECCIÓN DE DATOS ...................................................................22 7.5. ANÁLISIS ESTADÍSTICO .......................................................................23 8. CONSIDERACIONES ÉTICAS ..................................................................23 9. RESULTADOS ...........................................................................................24 10. DISCUSIÓN ……………………………………………………………………32 10. CONCLUSIONES ................................................................................... 37 11. BIBLIOGRAFÍA ...................................................................................... 38 12. ANEXOS ................................................................................................ 43 | spa |
| dc.format.mimetype | application/pdf | spa |
| dc.identifier.instname | instname:Universidad Autónoma de Bucaramanga - UNAB | spa |
| dc.identifier.reponame | reponame:Repositorio Institucional UNAB | spa |
| dc.identifier.repourl | repourl:https://repository.unab.edu.co | spa |
| dc.identifier.uri | http://hdl.handle.net/20.500.12749/33478 | |
| dc.language.iso | spa | spa |
| dc.publisher.faculty | Facultad Ciencias de la Salud | spa |
| dc.publisher.grantor | Universidad Autónoma de Bucaramanga UNAB | spa |
| dc.publisher.program | Especialización en Urología | spa |
| dc.publisher.programid | EURO-1271 | |
| dc.relation.references | Bögemann, M., Facchini, G., Bauernhofer, T. et al. Role of apalutamide in the treatment landscape for patients with advanced prostate cancer: an expert opinion statement of European clinical practice. Ir J Med Sci (2023). https://doi.org/10.1007/s11845-023-03303-y | spa |
| dc.relation.references | Agarwal N, George DJ, Klaassen Z, et al. Physician Reasons for or Against Treatment Intensification in Patients With Metastatic Prostate Cancer. JAMA Netw Open. 2024;7(12):e2448707. doi:10.1001/jamanetworkopen.2024.48707 | spa |
| dc.relation.references | Hussain M, Goldman B, Tangen C, Higano CS, Petrylak DP, Wilding G, Akdas AM, Small EJ, Donnelly BJ, Sundram SK, Burch PA, Dipaola RS, Crawford ED. Prostate-specific antigen progression predicts overall survival in patients with metastatic prostate cancer: data from Southwest Oncology Group Trials 9346 (Intergroup Study 0162) and 9916. J Clin Oncol. 2009 May 20;27(15):2450-6. doi: 10.1200/JCO.2008.19.9810. Epub 2009 Apr 20. PMID: 19380444; PMCID: PMC2684851 | spa |
| dc.relation.references | Lowentritt B, Pilon D, Khilfeh I, Rossi C, Muser E, Kinkead F, Waters D, Ellis L, Lefebvre P, Brown G. Attainment of early, deep prostate-specific antigen response in metastatic castration-sensitive prostate cancer: A comparison of patients initiated on apalutamide or enzalutamide. Urol Oncol. 2023 May;41(5):253.e1-253.e9. doi: 10.1016/j.urolonc.2023.03.003. Epub 2023 Apr 13. PMID: 37061452. | spa |
| dc.relation.references | Culp MB, Soerjomataram I, Efstathiou JA, Bray F, Jemal A. Recent Global Patterns in Prostate Cancer Incidence and Mortality Rates. Eur Urol. 2020 Jan;77(1):38-52. doi: 10.1016/j.eururo.2019.08.005. Epub 2019 Sep 5. PMID: 31493960 | spa |
| dc.relation.references | Devasia TP, Mariotto AB, Nyame YA, Etzioni R. Estimating the Number of Men Living with Metastatic Prostate Cancer in the United States. Cancer Epidemiol Biomarkers Prev. 2023 May 1;32(5):659-665. doi: 10.1158/1055-9965.EPI-22-1038. PMID: 36716178; PMCID: PMC10159917 | spa |
| dc.relation.references | Fondo Colombiano de Enfermedades de Alto Costo, Cuenta de Alto Costo (CAC). Situacion del cancer en la población adulta atendida en el SGSSS de Colombia 2023. Nombre del sitio web. https://cuentadealtocosto.org/publicaciones/situacion-del-cancer-en-la-poblacion-adulta-atendida-en-el-sgsss-de-colombia-2023/ | spa |
| dc.relation.references | Eggener S. Hormonal Therapy for Prostate Cancer. Campbell-Walsh-Wein Urology, 161, 3671-3686.e6 | spa |
| dc.relation.references | Perlmutter MA, Lepor H. Androgen deprivation therapy in the treatment of advanced prostate cancer. Rev Urol. 2007;9 Suppl 1(Suppl 1):S3-8. PMID: 17387371; PMCID: PMC1831539 | spa |
| dc.relation.references | Lisa M. Gudenkauf et al., Balancing Hormone Therapy: Mitigating Adverse Effects of Androgen-Deprivation Therapy and Exploring Alternatives in Prostate Cancer Management. Am Soc Clin Oncol Educ Book 44, e433126(2024). DOI:10.1200/EDBK_433126 | spa |
| dc.relation.references | Pickles T, Hamm J, Morris WJ, Schreiber WE, Tyldesley S. Incomplete testosterone suppression with luteinizing hormone-releasing hormone agonists: does it happen and does it matter? BJU Int. 2012 Dec;110(11 Pt B):E500-7. doi: 10.1111/j.1464-410X.2012.11190.x. Epub 2012 May 7. PMID: 22564197 | spa |
| dc.relation.references | Labban M, et al. Hormono Treatment of Prostate Cancer. Urologic Clinics of North America, 2022-05-01, Volume 49, Number 2, Pages 309-321, Copyright © 2022 Elsevier Inc | spa |
| dc.relation.references | James ND, Sydes MR, Clarke NW, Mason MD, Dearnaley DP, Spears MR, Ritchie AW, Parker CC, Russell JM, Attard G, de Bono J, Cross W, Jones RJ, Thalmann G, Amos C, Matheson D, Millman R, Alzouebi M, Beesley S, Birtle AJ, Brock S, Cathomas R, Chakraborti P, Chowdhury S, Cook A, Elliott T, Gale J, Gibbs S, Graham JD, Hetherington J, Hughes R, Laing R, McKinna F, McLaren DB, O'Sullivan JM, Parikh O, Peedell C, Protheroe A, Robinson AJ, Srihari N, Srinivasan R, Staffurth J, Sundar S, Tolan S, Tsang D, Wagstaff J, Parmar MK; STAMPEDE investigators. Addition of docetaxel, zoledronic acid, or both to first-line long-term hormone therapy in prostate cancer (STAMPEDE): survival results from an adaptive, multiarm, multistage, platform randomised controlled trial. Lancet. 2016 Mar 19;387(10024):1163-77. doi: 10.1016/S0140-6736(15)01037-5. Epub 2015 Dec 21. PMID: 26719232; PMCID: PMC4800035. | spa |
| dc.relation.references | Sweeney CJ, Chen YH, Carducci M, Liu G, Jarrard DF, Eisenberger M, Wong YN, Hahn N, Kohli M, Cooney MM, Dreicer R, Vogelzang NJ, Picus J, Shevrin D, Hussain M, Garcia JA, DiPaola RS. Chemohormonal Therapy in Metastatic Hormone-Sensitive Prostate Cancer. N Engl J Med. 2015 Aug 20;373(8):737-46. doi: 10.1056/NEJMoa1503747. Epub 2015 Aug 5. PMID: 26244877; PMCID: PMC4562797. | spa |
| dc.relation.references | Gravis G, Fizazi K, Joly F, Oudard S, Priou F, Esterni B, Latorzeff I, Delva R, Krakowski I, Laguerre B, Rolland F, Théodore C, Deplanque G, Ferrero JM, Pouessel D, Mourey L, Beuzeboc P, Zanetta S, Habibian M, Berdah JF, Dauba J, Baciuchka M, Platini C, Linassier C, Labourey JL, Machiels JP, El Kouri C, Ravaud A, Suc E, Eymard JC, Hasbini A, Bousquet G, Soulie M. Androgen-deprivation therapy alone or with docetaxel in non-castrate metastatic prostate cancer (GETUG-AFU 15): a randomised, open-label, phase 3 trial. Lancet Oncol. 2013 Feb;14(2):149-58. doi: 10.1016/S1470-2045(12)70560-0. Epub 2013 Jan 8. PMID: 23306100. | spa |
| dc.relation.references | Eisenhauer, E.A., et al. New response evaluation criteria in solid tumours: revised RECIST guideline (version 1.1). Eur J Cancer, 2009. 45: 228. https://pubmed.ncbi.nlm.nih.gov/19097774 | spa |
| dc.relation.references | Chandrasekar T, Yang JC, Gao AC, Evans CP. Mechanisms of resistance in castration-resistant prostate cancer (CRPC). Transl Androl Urol. 2015 Jun;4(3):365-80. doi: 10.3978/j.issn.2223-4683.2015.05.02. PMID: 26814148; PMCID: PMC4708226 | spa |
| dc.relation.references | Davis ID, Martin AJ, Stockler MR, Begbie S, Chi KN, Chowdhury S, Coskinas X, Frydenberg M, Hague WE, Horvath LG, Joshua AM, Lawrence NJ, Marx G, McCaffrey J, McDermott R, McJannett M, North SA, Parnis F, Parulekar W, Pook DW, Reaume MN, Sandhu SK, Tan A, Tan TH, Thomson A, Tu E, Vera-Badillo F, Williams SG, Yip S, Zhang AY, Zielinski RR, Sweeney CJ; ENZAMET Trial Investigators and the Australian and New Zealand Urogenital and Prostate Cancer Trials Group. Enzalutamide with Standard First-Line Therapy in Metastatic Prostate Cancer. N Engl J Med. 2019 Jul 11;381(2):121-131. doi: 10.1056/NEJMoa1903835. Epub 2019 Jun 2. PMID: 31157964 | spa |
| dc.relation.references | Armstrong AJ, Szmulewitz RZ, Petrylak DP, Holzbeierlein J, Villers A, Azad A, Alcaraz A, Alekseev B, Iguchi T, Shore ND, Rosbrook B, Sugg J, Baron B, Chen L, Stenzl A. ARCHES: A Randomized, Phase III Study of Androgen Deprivation Therapy With Enzalutamide or Placebo in Men With Metastatic Hormone-Sensitive Prostate Cancer. J Clin Oncol. 2019 Nov 10;37(32):2974-2986. doi: 10.1200/JCO.19.00799. Epub 2019 Jul 22. PMID: 31329516; PMCID: PMC6839905. | spa |
| dc.relation.references | Chi KN, Agarwal N, Bjartell A, Chung BH, Pereira de Santana Gomes AJ, Given R, Juárez Soto Á, Merseburger AS, Özgüroğlu M, Uemura H, Ye D, Deprince K, Naini V, Li J, Cheng S, Yu MK, Zhang K, Larsen JS, McCarthy S, Chowdhury S; TITAN Investigators. Apalutamide for Metastatic, Castration-Sensitive Prostate Cancer. N Engl J Med. 2019 Jul 4;381(1):13-24. doi: 10.1056/NEJMoa1903307. Epub 2019 May 31. PMID: 31150574 | spa |
| dc.relation.references | Chowdhury S, Bjartell A, Agarwal N, Chung BH, Given RW, Pereira de Santana Gomes AJ, Merseburger AS, Özgüroğlu M, Juárez Soto Á, Uemura H, Ye D, Brookman-May SD, Londhe A, Bhaumik A, Mundle SD, Larsen JS, McCarthy SA, Chi KN. Deep, rapid, and durable prostate-specific antigen decline with apalutamide plus androgen deprivation therapy is associated with longer survival and improved clinical outcomes in TITAN patients with metastatic castration-sensitive prostate cancer. Ann Oncol. 2023 May;34(5):477-485. doi: 10.1016/j.annonc.2023.02.009. Epub 2023 Feb 27. PMID: 36858151 | spa |
| dc.relation.references | Saad F, Hussain MHA, Tombal B, Fizazi K, Sternberg CN, Crawford ED, Nordquist LT, Bögemann M, Tutrone R, Shore ND, Belkoff L, Fralich T, Jhaveri J, Srinivasan S, Li R, Verholen F, Kuss I, Smith MR. Deep and Durable Prostate-specific Antigen Response to Darolutamide with Androgen Deprivation Therapy and Docetaxel, and Association with Clinical Outcomes for Patients with High- or Low-volume Metastatic Hormone-sensitive Prostate Cancer: Analyses of the Randomized Phase 3 ARASENS Study. Eur Urol. 2024 Oct;86(4):329-339. doi: 10.1016/j.eururo.2024.03.036. Epub 2024 Apr 21. PMID: 38644146 | spa |
| dc.relation.references | Benjamin L. Maughan et al., Rapid and deep prostate-specific antigen (PSA) response to apalutamide plus ADT and survival in metastatic castration-sensitive prostate cancer (mCSPC) in real world practice in the US (OASIS Project).. JCO 42, 5076-5076(2024). DOI:10.1200/JCO.2024.42.16_suppl.5076 | spa |
| dc.relation.references | Fizazi, Karim et al.. Abiraterone plus prednisone added to androgen deprivation therapy and docetaxel in de novo metastatic castration-sensitive prostate cancer (PEACE-1): a multicentre, open-label, randomised, phase 3 study with a 2 × 2 factorial design. The Lancet, Volume 399, Issue 10336, 1695 - 1707 | spa |
| dc.relation.references | Saad F, Small EJ, et al. Deep Prostate-specific Antigen Response following Addition of Apalutamide to Ongoing Androgen Deprivation Therapy and Long-term Clinical Benefit in SPARTAN. Eur Urol. 2022 Feb;81(2):184-192. doi: 10.1016/j.eururo.2021.11.020. Epub 2021 Dec 13. PMID: 34916086 | spa |
| dc.relation.references | Matsubara N, Chi KN, et al. Correlation of Prostate-specific Antigen Kinetics with Overall Survival and Radiological Progression-free Survival in Metastatic Castration-sensitive Prostate Cancer Treated with Abiraterone Acetate plus Prednisone or Placebos Added to Androgen Deprivation Therapy: Post Hoc Analysis of Phase 3 LATITUDE Study. Eur Urol. 2020 Apr;77(4):494-500. doi: 10.1016/j.eururo.2019.11.021. Epub 2019 Dec 13. PMID: 31843335 | spa |
| dc.relation.references | Fizazi K, Tran N, Fein L, Matsubara N, Rodriguez-Antolin A, Alekseev BY, Özgüroğlu M, Ye D, Feyerabend S, Protheroe A, Sulur G, Luna Y, Li S, Mundle S, Chi KN. Abiraterone acetate plus prednisone in patients with newly diagnosed high-risk metastatic castration-sensitive prostate cancer (LATITUDE): final overall survival analysis of a randomised, double-blind, phase 3 trial. Lancet Oncol. 2019 May;20(5):686-700. doi: 10.1016/S1470-2045(19)30082-8. Epub 2019 Apr 12. PMID: 30987939 | spa |
| dc.relation.references | Lowentritt B, Pilon D, Waters D, Rossi C, Muser E, Kurteva S, Shah A, Khilfeh I, Du S, Ellis L, Lefebvre P, Brown G. Comparison of prostate-specific antigen response in patients with metastatic castration-sensitive prostate cancer initiated on apalutamide or abiraterone acetate: A retrospective cohort study. Urol Oncol. 2023 May;41(5):252.e19-252.e27. doi: 10.1016/j.urolonc.2023.03.013. Epub 2023 Apr 19. PMID: 37080833 | spa |
| dc.relation.references | Liu J, Wang S, et al. Real-world retrospective study of prostate-specific antigen and safety assessment with darolutamide plus androgen deprivation therapy for metastasis hormone-sensitive prostate cancer. Transl Androl Urol. 2024 Mar 31;13(3):433-441. doi: 10.21037/tau-24-96. Epub 2024 Mar 25. PMID: 38590967; PMCID: PMC10999023 | spa |
| dc.relation.references | Hussain M, Fizazi K, Saad F, Rathenborg P, Shore N, Ferreira U, Ivashchenko P, Demirhan E, Modelska K, Phung D, Krivoshik A, Sternberg CN. Enzalutamide in Men with Nonmetastatic, Castration-Resistant Prostate Cancer. N Engl J Med. 2018 Jun 28;378(26):2465-2474. doi: 10.1056/NEJMoa1800536. PMID: 29949494; PMCID: PMC8288034. | spa |
| dc.relation.references | Fizazi K, Shore N, Tammela TL, Ulys A, Vjaters E, Polyakov S, Jievaltas M, Luz M, Alekseev B, Kuss I, Kappeler C, Snapir A, Sarapohja T, Smith MR; ARAMIS Investigators. Darolutamide in Nonmetastatic, Castration-Resistant Prostate Cancer. N Engl J Med. 2019 Mar 28;380(13):1235-1246. doi: 10.1056/NEJMoa1815671. Epub 2019 Feb 14. Erratum in: N Engl J Med. 2022 Sep 1;387(9):860. doi: 10.1056/NEJMx220007. PMID: 30763142 | spa |
| dc.relation.references | Santoni M, Büttner T, et al. . Apalutamide in Metastatic Castration-sensitive Prostate Cancer: Results from the Multicenter Real-world ARON-3 Study. Eur Urol Oncol. 2025 Apr;8(2):444-451. doi: 10.1016/j.euo.2024.11.005. Epub 2024 Nov 29. PMID: 39613567 | spa |
| dc.relation.references | Mehmet A. Billen, Shawn Du. et al. Real-World survival of patients with metastatic castration-sensitive prostate cancer initiated on apalutamide or enzalutamide in an oncology database: ROME Study. Presented at American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU); January 25-27, 2024; San Francisco, CA and online | spa |
| dc.relation.references | Lowentritt B, DU S. et al. Real-World Comparison of Prostate-Specific Antigen Response in Patients with Metastatic Castration-Sensitive Prostate Cancer Treated with Apalutamide or Enzalutamide (PROMPT-1). Presented at American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU); January 25-27, 2024; San Francisco, CA and online | spa |
| dc.rights.accessrights | info:eu-repo/semantics/openAccess | spa |
| dc.rights.creativecommons | Atribución-NoComercial-SinDerivadas 2.5 Colombia | * |
| dc.rights.local | Abierto (Texto Completo) | spa |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/2.5/co/ | * |
| dc.subject.keywords | Medical sciences | spa |
| dc.subject.keywords | Health sciences | spa |
| dc.subject.keywords | Urology | spa |
| dc.subject.keywords | Medicine | spa |
| dc.subject.keywords | Prostate cancer | spa |
| dc.subject.keywords | Androgen receptor antagonists | spa |
| dc.subject.keywords | Prostate-specific antigen | spa |
| dc.subject.keywords | Metastatic prostate cancer | spa |
| dc.subject.keywords | Cancer (Hormone therapy) | spa |
| dc.subject.keywords | Cancer (Treatment) | spa |
| dc.subject.keywords | Hormone therapy | spa |
| dc.subject.lemb | Urología | spa |
| dc.subject.lemb | Medicina | spa |
| dc.subject.lemb | Ciencias médicas | spa |
| dc.subject.lemb | Cáncer (Terapia hormonal) | spa |
| dc.subject.lemb | Cáncer (Tratamiento) | spa |
| dc.subject.lemb | Terapia hormonal | spa |
| dc.subject.proposal | Ciencias de la salud | spa |
| dc.subject.proposal | Cáncer de próstata | spa |
| dc.subject.proposal | Antagonista de andrógenos | spa |
| dc.subject.proposal | Antígeno prostático específico | spa |
| dc.title | Capacidad de los antiandrógenos de nueva generación en disminuir el antígeno prostático específico en pacientes con cáncer de próstata metastásico | spa |
| dc.title.translated | The capacity of next-generation antiandrogens to reduce Prostate-Specific Antigen (PSA) in patients with metastatic prostate cancer | spa |
| dc.type.coar | http://purl.org/coar/resource_type/c_bdcc | |
| dc.type.coarversion | http://purl.org/coar/version/c_ab4af688f83e57aa | spa |
| dc.type.driver | info:eu-repo/semantics/masterThesis | |
| dc.type.hasversion | info:eu-repo/semantics/acceptedVersion | |
| dc.type.local | Tesis | spa |
| dc.type.redcol | http://purl.org/redcol/resource_type/TM |
Archivos
Bloque de licencias
1 - 1 de 1
Cargando...
- Nombre:
- license.txt
- Tamaño:
- 829 B
- Formato:
- Item-specific license agreed upon to submission
- Descripción: