Background Glioblastoma (GB) is the most aggressive primary brain tumor in adults and is traditionally associated with a poor prognosis. In 2009, Uruguay's National Resource Fund (Fondo Nacional de Recursos [FNR]) began guaranteeing universal public funding for standard temozolomide (TMZ), establishing an accessible standard of care. This study evaluates the long-term real-world survival impact of that policy and discusses its implications for the future integration of high-cost immunotherapies. Methods We conducted a retrospective observational cohort study of adult patients with histologically confirmed supratentorial hemispheric GB who completed initial diagnosis and treatment between January 2009 and December 2017 at the Neuro-Oncology Unit of the Hospital de Clínicas "Dr. Manuel Quintela", Montevideo, Uruguay. Follow-up extended through December 2018. Overall survival (OS) was estimated using the Kaplan-Meier method, and the study was reported in accordance with the STROBE guidelines. Results A total of 32 patients met the inclusion criteria. Mean age was 50.7 ± 15.3 years (range: 19-75 years), and 62.5% (n = 20) were male. Gross total resection was achieved in 56.3% of cases. Median OS for the entire cohort was 17 months (95% CI: 7.0-26.9). Patients who completed the full adjuvant Stupp regimen achieved a significantly longer median OS than those with incomplete treatment (24 vs. 11 months; log-rank p = 0.023). Conclusions Universal public funding for TMZ in Uruguay has achieved real-world outcomes consistent with international benchmarks. However, the biological ceiling of the Stupp regimen underscores the urgent need for molecular profiling. As the therapeutic landscape shifts toward ultra-high-cost immunotherapies, establishing this historical baseline is essential for the development of sustainable, equity-driven health policies in middle-income countries.

PURPOSEBreast cancer mortality rates in Latin America (LA) are higher than those in the United States, possibly because of advanced disease presentation, health care disparities, or unfavorable molecular subtypes. The Latin American Cancer Research Network was established to address these challenges and to promote collaborative clinical research. The Molecular Profiling of Breast Cancer Study (MPBCS) aimed to evaluate the clinical characteristics and treatment outcomes of LA participants with locally advanced breast cancer (LABC).PATIENTS AND METHODSThe MPBCS enrolled 1,449 participants from Argentina, Brazil, Chile, Mexico, and Uruguay. Through harmonized procedures and quality assurance measures, this study evaluated clinicopathologic characteristics, neoadjuvant chemotherapy response, and survival outcomes according to residual cancer burden (RCB) and the type of surgery.RESULTSOverall, 711 and 480 participants in the primary surgery and neoadjuvant arms, respectively, completed the 5-year follow-up period. Overall survival was independently associated with RCB (worse survival for RCBIII-adjusted hazard ratio, 8.19, P < .001, and RCBII [adjusted hazard ratio, 3.69, P < .008] compared with RCB0 [pathologic complete response or pCR]) and type of surgery (worse survival in mastectomy than in breast-conserving surgery [BCS], adjusted hazard ratio, 2.97, P = .001). The hormone receptor–negative-human epidermal growth factor receptor 2–positive group had the highest proportion of pCR (48.9%). The analysis of the ASCO Quality Oncology Practice Initiative breast module revealed high compliance with pathologic standards but lower adherence to treatment administration standards. Notably, compliance with trastuzumab administration varied widely among countries (33.3%-88.7%).CONCLUSIONIn LABC, we demonstrated the survival benefit of BCS and the prognostic effect of the response to available neoadjuvant treatments despite an important variability in access to key treatments. The MPBCS represents a significant step forward in understanding the real-world implementation of oncologic procedures in LA.

Purposes:Most molecular-based published studies on breast cancer do not adequately represent the unique and diverse genetic admixture of the Latin American population. Searching for similarities and differences in molecular pathways associated with these tumors and evaluating its impact on prognosis may help to select better therapeutic approaches.Patients and Methods:We collected clinical, pathological, and transcriptomic data of a multi-country Latin American cohort of 1,071 stage II-III breast cancer patients of the Molecular Profile of Breast Cancer Study (MPBCS) cohort. The 5-year prognostic ability of intrinsic (transcriptomic-based) PAM50 and immunohistochemical classifications, both at the cancer-specific (OSC) and disease-free survival (DFS) stages, was compared. Pathway analyses (GSEA, GSVA and MetaCore) were performed to explore differences among intrinsic subtypes.Results:PAM50 classification of the MPBCS cohort defined 42·6% of tumors as LumA, 21·3% as LumB, 13·3% as HER2E and 16·6% as Basal. Both OSC and DFS for LumA tumors were significantly better than for other subtypes, while Basal tumors had the worst prognosis. While the prognostic power of traditional subtypes calculated with hormone receptors (HR), HER2 and Ki67 determinations showed an acceptable performance, PAM50-derived risk of recurrence best discriminated low, intermediate and high-risk groups. Transcriptomic pathway analysis showed high proliferation (i.e. cell cycle control and DNA damage repair) associated with LumB, HER2E and Basal tumors, and a strong dependency on the estrogen pathway for LumA. Terms related to both innate and adaptive immune responses were seen predominantly upregulated in Basal tumors, and, to a lesser extent, in HER2E, with respect to LumA and B tumors.Conclusions:This is the first study that assesses molecular features at the transcriptomic level in a multicountry Latin American breast cancer patient cohort. Hormone-related and proliferation pathways that predominate in PAM50 and other breast cancer molecular classifications are also the main tumor-driving mechanisms in this cohort and have prognostic power. The immune-related features seen in the most aggressive subtypes may pave the way for therapeutic approaches not yet disseminated in Latin America.Clinical Trial Registration:ClinicalTrials.gov (Identifier: NCT02326857).

Molecular profile of breast cancer in Latin-American women was studied in five countries: Argentina, Brazil, Chile, Mexico, and Uruguay. Data about socioeconomic characteristics, risk factors, prognostic factors, and molecular subtypes were described, and the 60-month overall cumulative survival probabilities (OS) were estimated. From 2011 to 2013, 1,300 eligible Latin-American women 18 years or older, with a diagnosis of breast cancer in clinical stage II or III, and performance status ≦̸1 were invited to participate in a prospective cohort study. Face-to-face interviews were conducted, and clinical and outcome data, including death, were extracted from medical records. Unadjusted associations were evaluated by Chi-squared and Fisher’s exact tests and the OS by Kaplan–Meier method. Log-rank test was used to determine differences between cumulative probability curves. Multivariable adjustment was carried out by entering potential confounders in the Cox regression model. The OS at 60 months was 83.9%. Multivariable-adjusted death hazard differences were found for women living in Argentina (2.27), Chile (1.95), and Uruguay (2.42) compared with Mexican women, for older (≥60 years) (1.84) compared with younger (≤40 years) women, for basal-like subtype (5.8), luminal B (2.43), and HER2-enriched (2.52) compared with luminal A subtype, and for tumor clinical stages IIB (1.91), IIIA (3.54), and IIIB (3.94) compared with stage IIA women. OS was associated with country of residence, PAM50 intrinsic subtype, age, and tumor stage at diagnosis. While the latter is known to be influenced by access to care, including cancer screening, timely diagnosis and treatment, including access to more effective treatment protocols, it may also influence epigenetic changes that, potentially, impact molecular subtypes. Data derived from heretofore understudied populations with unique geographic ancestry and sociocultural experiences are critical to furthering our understanding of this complexity.

Abstract Although gene expression-derived PAM50 intrinsic subtypes (LumA, LumB, HER2E and Basal) were reported in Latin American breast cancer, most studies did not adequately represent the unique and diverse genetic admixture of the Latin American population and/or included a small number of individuals. As a result of these limitations, confirmation of the prognostic value of available intrinsic subtype classification signatures in a diverse cohort of Latin American women is of utmost importance. We assessed the general distribution and prognostic performance of PAM50-based intrinsic and immunohistochemistry (IHC)-based surrogate subtype classifications in Latin American women included in the Molecular Profile of Breast Cancer Study (MPBCS), an initiative of the US-Latin America Cancer Research Network (US-LACRN) comprising institutions of Argentina, Brazil, Chile, Mexico and Uruguay. MPBCS focused on stage II-III breast cancer in Latin American women. Eligible enrolled patients (n=1300) were characterized clinically, pathologically and epidemiologically and followed-up for 5 years. IHC subtypes were assessed according to St Gallen's 2013 criteria, using Ki67 to discriminate LumB from LumA tumors. A total of 1071 tumors were characterized by gene-expression microarrays. PAM50 classification defined 45% of tumors as LumA, 19.7% as LumB, 13.8% as HER2E and 17.5% as Basal. Normal-like tumors (6.3%) were excluded from the analysis. The 5-year prognostic ability of PAM50 and IHC classifications, both at the cancer-specific (OS) and progression-free survival (PFS), was tested. The prognosis for LumA tumors was significantly better than for other subtypes, while Basal-like tumors had the worst prognosis. The prognostic power of IHC-based subtypes (C-index 0.698 for OS, 0.635 for PFS) was very similar to that of PAM50 (C-index 0.678 for OS, 0.639 for PFS), indicating that in US-LACRN-MPBCS, contrary to other cohorts, surrogate subtypes are as useful as PAM50 for discriminating recurrence risk. PAM50-derived risks of recurrence (RORs), in particular ROR-S (C-index 0.699 for OS, 0.649 for PFS), clearly discriminated risk into low, intermediate and high-risk groups. Transcriptomic pathway analysis showed high proliferation (i.e. cell cycle control and DNA damage repair) associated with LumB, HER2E and Basal tumors, and a strong dependency on the estrogen pathway for LumA. Overall, a general concordance of the molecular features of US-LACRN-MPBCS breast cancer tumors with those of other cohorts was confirmed. The shift towards non-luminal subtypes could be partly attributable to the recruitment bias towards advanced stages. Further refinement of analyses using molecular ancestry assignation may help to reveal more subtle differences in this heterogeneously admixed population. Citation Format: Andrea S. Llera, Eliana Abdelhay, Osvaldo Podhajcer, Nora Artagaveytia, Adrián Daneri-Navarro, Bettina Müller, Carlos Velázquez Contreras, Darío Rocha, Juan Martín Sendoya, Renata Binato, Elmer Fernández, Elsa Alcoba, Isabel Alonso, Alicia I. Bravo, Natalia Camejo, Dirce Carraro, Mónica Castro, Juan M. Castro-Cervantes, Sandra Cataldi, Alfonso Cayota, Mauricio Cerda, Susanne Crocamo, Raul Delgadillo-Cisterna, Lucía Delgado, Alicia del Toro Arreola, Marisa Dreyer Breitenbach, Jorge Fernández, Wanda Fernández, Ramon A. Franco-Topete, Fancy Gaete, Jorge Gómez, Gonzalo Greif, Marisol Guerrero, Marianne Marianne Henderson, Andres de J Moran-Mendoza, María Aparecida Nagai, Antonio Oceguera-Villanueva, Antonio Quintero-Ramos, Rui Reis, Javier Retamales, Robinson Rodríguez, Cristina Rosales, Efrain Salas-González, Laura Segovia, Araceli Silva-García, Vidya Vedham, Livia Zagame, The US-Latin American Cancer Research Network. Molecular features of breast cancer involved in classification and prognosis of a multi-country Latin American cohort: The US-LACRN-MPBCS breast cancer cohort [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 608.

Background: Pertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting. Patients and methods: In the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8 mg/kg loading dose, then 6 mg/kg every 3 weeks (q3w)] and pertuzumab (840 mg loading dose, then 420 mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS). Results: Overall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54 years; 29% had received prior trastuzumab. Median treatment duration was 16 months for pertuzumab and trastuzumab and 4 months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months' median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9-22.7] months overall (19.6, 23.0 and 18.1 months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%-82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%). Conclusions: Preliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile.

Introduction: glioblastoma multiforme (GBM) is the most agressive kind of gliomas. The 5-year survival rate for exclusive surgical treatment is null. Additional chemotherapy and radiotherapy increases survival.Objective: to evaluate the impact of treatment in the survival of patients suffering from GBM.Method: patients with a histological diagnosis of GBM who were seen at the Neuro-Oncology Unit of the Clinicas Hospital, from 1980 through 2000. Clinical, paraclinical and patronymic data was collected, the same as information on the evolution of medical records. Survival rates were calculated through the Kaplan Meier and Mantel Cox method.Results: 65 patients with an average age of 58 years old were studied,(range:6-79). All of them underwent surgery (complete in 22 patients, subtotal in 9, partial in 32 and biopsy in 2 patients). Ninety two percent of patients were treated with radiotherapy and 25% with chemotherapy. Median survival was 46.6 weeks and global survival one year after was 28%. The probability for survival one year after was 0 in patients who were treated only with surgery; 0.23 in those who also received radiotherapy and 0.62 with chemotherapy QT(p= 0,0001). Multivariable analysis identified the following independent variables: multimodal treatment including chemotherapy (p= 0,003) and a good postoperative general condition (p= 0,007).Conclusions: median survival in this series was similar to that described in literature, there existing a longer survival rate for patients with a good neurologic condition who are treated with radiotherapy and chemotherapy after surgery.

Introducción: el cáncer de mama (CM) constituye una enfermedad heterogénea reconociéndose subtipos con diferentes características mediante, entre otras técnicas, el estudio del nivel de expresión tumoral de los receptores hormonales (RRHH) y del HER2. Previamente reportamos la relación entre estos subtipos y características clínico-patológicas en pacientes uruguayas. Objetivo: analizar la sobrevida libre de enfermedad (SVLE) de pacientes uruguayas con cáncer de mama de acuerdo a su subtipo biológico, definido en base a la expresión tumoral de HER2 y RRHH evaluada mediante inmunohistoquímica. Material y método: se revisaron historias clínicas de pacientes intervenidas quirúrgicamente por CM estadios I-III en un período de dos años, realizándose el cálculo de SVLE para todas las pacientes y según subtipo biológico. Resultados: con seguimiento mediano de 40 meses, la SVLE a dos años para el total de las pacientes fue de 92,3%; 94% para las pacientes RRHH+/HER2-, 91% para las triple negativas (TN) y 71,4% para las HER2+. La comparación de las curvas de SVLE, según los diferentes subtipos, mostró menor SVLE para las pacientes HER2+ (p = 0,03) y similar SVLE de las pacientes RRHH+/HER2- y TN (p = 0,86). Conclusiones: las pacientes uruguayas con CM presentan una SVLE a dos años acorde a los reportes internacionales. Las pacientes HER2+ presentan una mayor tasa de recidivas, lo cual también es coincidente a lo reportado. La similar SVLE a dos años de las pacientes RRHH+/HER 2- y de las TN no se explicaría por diferencias en características clínico-patológicas, planteándose como hipótesis una mayor proporción de pacientes del subtipo luminal B entre las pacientes RRHH+/ HER 2-.

Introducción: el glioblastoma multiforme (GBM) representa la forma más agresiva de los gliomas. La sobrevida a cinco años con el tratamiento quirúrgico exclusivo es nula. El agregado radioterapia (RT) y quimioterapia (QT) prolongan la sobrevida. Objetivo: evaluar el impacto del tratamiento en la sobrevida de pacientes portadores de GBM. Pacientes y métodos: se incluyeron los pacientes con diagnóstico histológico de GBM asistidos en la Unidad de Neuro-Oncología del Hospital de Cínicas, de 1980 a 2000. Se recabaron datos patronímicos, clínicos, paraclínicos y evolutivos de las historias clínicas. Se calculó la sobrevida mediante el método de Kaplan Meier y Mantel Cox. Resultados: se estudiaron 65 pacientes con una edad mediana de 58 años (rango: 6-79). Recibieron cirugía 100% (completa en 22 pacientes, subtotal en 9, parcial en 32 y biopsia en 2). El 92% recibió RT posoperatoria y 25% QT. La mediana de sobrevida fue de 46,6 semanas y la sobrevida global al año fue de 28%. La probabilidad de sobrevida al año fue 0 en los pacientes que recibieron cirugía exclusiva; 0,23 en los que se agregó RT, y 0,62 en los tratados con QT (p=0,0001). El análisis multivariable identificó como variables independientes: el tratamiento multimodal incluyendo quimioterapia (p=0,003) y buen estado neurológico posoperatorio (p=0,007). Conclusiones: la mediana de sobrevida de esta serie fue similar a lo descrito en la literatura, existiendo una sobrevida mayor en los pacientes con buen estado neurológico tratados con cirugía seguida de RT y QT.

Introduction: breast cancer constitutes an heterogeneous disease. Two sub-types have been distinguished through the study of the tumor expression level of hormone receptors tumors, and level of HER2 expression, among other techniques. We previously reported the relation between these sub-types and the clinical and pathological characteristics of Uruguayan women.Objective: to analyse the disease-free survival (DFS) of Uruguayan patients with breast cancer, according to their biological sub-type, defined based on the tumor expression of hormone receptors and HER2 expression which were assessed by immune-histological chemistry staining.Method: all clinical records of patients who had undergone breast cancer surgery (StagesI-III) during a two year period were reviewed. The disease-free survival rate was calculated for all patients and according to their biological profile.Results: forty months follow up revealed disease-free survival upon two years of 92.3% for all patients; 94% for hormone receptor positive/HER2 negative patients, 91% for triple negative patients, and 71.4% for hormone receptor positive patients.Comparing the DFS curves, for the different sub-types, evidenced a lower DFS for HER2+patients (p = 0.03), and similar DFS for hormone receptor positive/ HER2 negative and triple negative ( p=0.86).Conclusions: uruguayan patients with breast cancer show a two-year-DFS that matches international reports. HER2+ patients evidence a higher relapse rate, also consistent with international reports. Similar DFS upon two years, between hormone receptor positive/HER2 negative patients and triple negative patients cannot be due to differences in the clinical-pathological characteristics, thus a hypothesis is considered: there is a larger proportion of patients of the luminalB breast cancer sub-type among hormone receptor positive/HER2 negative patients.

Introduction: breast cancer, the main cause of death of Uruguayan women, is an heterogeneous disease. Study of the tumoral expression of the Human Epidermal growth factor Receptor-2 (HER2), the estrogen receptor and the progesterone receptor enables the recognition of subtypes with different clinical, and pathological characteristics and evolution.Objectives: to learn about the HER2, estrogen receptor and progesterone receptor tumoral expression profile and their relationship with clinical-pathological characteristics in Uruguayan patients with breast cancer.Method: we reviewed the medical record of patients who underwent surgery for invasive breast cancer within a two year period, and we selected those who had determination of estrogen receptor, progesterone receptor and HER2 through immune-histochemestry. We compared the expression profile of these markers with the age at the time of diagnosis, the histological type and degree and the pathological status.Results: we selected 197 patients with the following characteristics: average age: 55 years old, ductal carcinoma: 85%, histological degree 1-2: 59%; stage I-II: 75%, axillary metastasis: 51%, progesterone receptor/estrogen receptors+(RE/RP+): 78%, HER2+: 10%. Three subtypes were defined: HER2-RE/RP+(73%),HER2+(10%) and triple negative (TN) (17%). Subtypes TN and HER2+ were associated with a greater histological degree (GH) (p<0,05) and the TN with lower age at the time of diagnosis than the HER2-, RE/RP+ subtype.Conclusions: the percentage of patients with HER2+ subtype invasive breast cancer (10%) is lower than the one reported in others studies. In accordance with previous studies, TN and HER2+ subtypes correlated with less differentiated tumors and TN subtype occurred in younger patients

Introduction: breast cancer, the main cause of death of Uruguayan women, is an heterogeneous disease. Study of the tumoral expression of the Human Epidermal growth factor Receptor-2 (HER2), the estrogen receptor and the progesterone receptor enables the recognition of sub-types with different clinical, and pathological characteristics and evolution.Objectives: to learn about the HER2, estrogen receptor and progesterone receptor tumoral expression profile and their relationship with clinical-pathological characteristics in Uruguayan patients with breast cancer.Method: we reviewed the medical record of patients who underwent surgery for invasive breast cancer within a two year period, and we selected those who had determination of estrogen receptor, progesterone receptor and HER2 through immune-histochemestry. We compared the expression profile of these markers with the age at the time of diagnosis, the histological type and degree and the pathological status.Results: we selected 197 patients with the following characteristics: average age: 55 years old, ductal carcinoma: 85%, histological degree 1-2: 59%; stage I-II: 75%, axillary metastasis: 51%, progesterone receptor/estrogen receptors+ (RE/RP+): 78%, HER2+: 10%. Three subtypes were defined: HER2- RE/RP+ (73%), HER2+ (10%) and triple negative (TN) (17%). Subtypes TN and HER2+ were associated with a greater histological degree (GH) (p<0,05) and the TN with lower age at the time of diagnosis than the HER2-, RE/RP+ subtype.Conclusions: the percentage of patients with HER2+ subtype invasive breast cancer (10%) is lower than the one reported in others studies. In accordance with previous studies, TN and HER2+ subtypes correlated with less differentiated tumors and TN subtype occurred in younger patients.

Introducción: el cáncer de mama (CM), principal causa de muerte por cáncer en la mujer uruguaya, constituye una enfermedad heterogénea. El estudio de la expresión tumoral del receptor del factor de crecimiento epidérmico-2 (HER2), el receptor de estrógenos (RE) y el receptor de progesterona (RP) permite reconocer subtipos con diferentes características clínico-patológicas y evolutivas. Objetivos: conocer el perfil de expresión tumoral de HER2, RE y RP y su relación con características clínico-patológicas en pacientes uruguayas con CM. Material y método: se revisaron las historias clínicas de pacientes intervenidas quirúrgicamente por CM invasivo en un período de dos años, seleccionándose las que contaban con la determinación de RE, RP y HER2 mediante inmunohistoquímica. Se comparó el perfil de expresión de estos marcadores con la edad al diagnóstico, tipo y grado histológico (GH) y estadio patológico (TNM). Resultados: se seleccionaron 197 pacientes cuyas características fueron edad media: 55 años, carcinoma ductal: 85%, GH 1-2: 59%, estadio: I-II: 75%, metástasis axilares: 51%, RE/RP+: 78%, HER2+: 10%. Se definieron tres subtipos: HER2- RE/RP+ (73%), HER2+ (10%) y triple negativo (TN) (17%). Los subtipos TN y HER2+ se asociaron con mayor grado histológico (p<0,05) y el TN con menor edad al diagnóstico (p<0,05) que el subtipo HER2-, RE/RP+. Conclusiones: el porcentaje de pacientes con CM invasivo subtipo HER2+ (10%) es menor que el reportado por otros estudios (17%-28%). En concordancia con estudios previos, los subtipos TN y HER2+ se correlacionaron con tumores más indiferenciados y el TN se presentó en pacientes más jóvenes.

Introducción: las complicaciones tromboembólicas se presentan en 15% de los pacientes con cáncer. Los pacientes portadores de tumores primarios o secundarios a nivel del sistema nervioso central (SNC) agregan, a los reconocidos factores de riesgo identificados en los pacientes oncológicos, elementos particulares que los hacen especialmente propensos a esta complicación. El reconocido riesgo que implica la administración de anticoagulantes en pacientes con lesiones en el SNC es frecuentemente sobrevalorado, por lo que suelen no indicarse con criterio profiláctico. Por otra parte, una vez producida la complicación trombótica debemos instaurarlos a dosis terapéuticas. Objetivo: valorar los riesgos y beneficios inherentes a la administración de anticoagulantes con criterio profiláctico y terapéutico en pacientes portadores de tumores a nivel del SNC. Método: se realiza una revisión de la bibliografía publicada en los últimos diez años sobre el tema. Conclusiones: la indicación de tratamiento anticoagulante profiláctico con warfarina a bajas dosis en pacientes ambulatorios portadores de tumores encefálicos debe basarse en la valoración del riesgo-beneficio individual y la posibilidad de control paraclínico estrecho. En el contexto de una intervención quirúrgica el beneficio de la profilaxis tromboembólica, con heparina fraccionada o de bajo peso molecular, supera el riesgo hemorrágico, con un margen aún mayor en la neurocirugía. Los pacientes que presentan complicaciones tromboembólicas mayores se benefician de la administración de tratamiento anticoagulante con criterio terapéutico siempre que se mantenga un estrecho control de las dosis dentro del rango terapéutico.

Background: thromboembolic complications are seen in 15% of patients with cancer. Patients with primary or secundary tumors of the central nervous system add to usual risk factors for oncologic patients, specific factors for thromboembolic complications.Since associated-risk to anticoagulant administration in patients with central nervous system injuries is usually overvalued, it is not usually recommended as prophylactic criteria. On the other way, once tromboembolic complications are proved, a therapeutic dosage must be indicated.Objective: to assess risk/benefit of anticoagulant administration to patients with central nervous system tumors according to prophylactic and therapeutic criteria.Methods: a ten-years old specific bibliography was reviewed.Conclusions: low dosage of anticoagulant administration with warfarine based on risk-benefit assessment and paramedical follow up is indicated in ambulatory pa-tients with encephalic tumors.Thromboembolic prophylaxis benefit in surgery with low molecular weight heparine overtake haemorragic risk better than neurosurgery.Patients with thromboembolic complications benefited from anticoagulant administration as far as dosage follow up ranged therapeutic average.

Introducción: Desde la observación que las pacientes que recibían adyuvancia con hormonoterapia en base a Tamoxifeno presentaban una disminución del 39% en la incidencia de cáncer mamario contralateral, se planteó el beneficio de su utilización con criterio quimiopreventivo. La factibilidad de esta estrategia fue confirmada y se inician múltiples estudios para confirmar el beneficio del tratamiento quimiopreventivo, la población blanco y su perfil de toxicidad. Objetivo: Analizar los estudios publicados hasta la actualidad sobre quimioprevención en cáncer de mama, las recomendaciones realizadas y delinear las principales indicaciones sobre quimioprevención que podrían aplicarse en nuestro medio. Discusión: De los trabajos publicados sobre quimioprevención en cáncer de mama hasta la actualidad el fármaco más estudiado es el Tamoxifeno. Se destaca el estudio NSABP-P1 como el estudio de mejor diseño, con mayor número de pacientes. De todas las recomendaciones expuestas se destacan un acuerdo en la delimitación de una población que se beneficiaría del tratamiento quimiopreventivo en base a Tamoxifeno. El tratamiento en base a Tamoxifeno 20 mg/d por 5 años con criterio preventivo debe indicarse luego de una valoración individual e informada del índice beneficio/riesgo de la paciente a la cual nos enfrentamos. Todas las recomendaciones coinciden en la indicación de este tratamiento a pacientes con antecedente de carcinoma lobulillar in situ (CLIS), hiperplasia atípica o que tengan 2 o más familiares de primer grado con cáncer mamario. El beneficio es claro en pacientes menores de 50 años y mayores de 50 años con histerectomía sin factores de riesgo tromboembólico. Artículo Recibido: 6 de julio de 2004.Artículo aceptado: 8 de noviembre de 2004. Dirección de correspondencia: Dr.Robinson Rodríguez Servicio de Oncología Clínica – Hospital de Clínicas Avda.Italia s/n. PB. Telefax: 487 2075 E-mail: rrodri@hc.edu.uy

Se presenta la serie de validación de la técnica del ganglio centinela para el manejo selectivo de la axila en el cáncer de mama. Las tasas de identiicación (95%) y el valor predictivo negativo (95%) avalan su eficacia en la predicción del compromiso axilar por carcinoma mamario.