Real-world implementation of North American and SIOP strategies for the treatment of Wilms tumor in Uruguay.

Wilms tumor has been selected as an index tumor by the WHO Global Initiative for Childhood Cancer with the aim to improve cure rates worldwide. Nevertheless, there is a scarcity of published data on outcomes beyond those of the major cooperative groups. Therefore, we conducted a retrospective analysis including all patients with Wilms tumor treated at our referral center in Uruguay between 1995 and 2020. Treatment consisted of North American (NA) strategies in 23 cases (1995-2004), followed by the SIOP strategy in 35 cases thereafter. Staging included: I-II = 28, III = 7, IV = 14, and V = 9. There were no major surgical or medical complications; however, a delay in the administration of local radiotherapy was observed (median of 21 days after surgery). There were no cases of toxicity- or surgery-related deaths or treatment abandonment. Five-year probability of overall survival was 0.72 and 0.92 for the NA and SIOP groups, respectively. We conclude that outcomes were better for the SIOP strategy with no unexpected toxicities and high treatment compliance in both strategies. Timely implementation of radiotherapy was challenging.

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.

Long-Term Kidney and Cardiovascular Complications in Pediatric Cancer Survivors.

OBJECTIVE: The objective of this study was to describe the burden of adverse kidney and hypertension outcomes in patients evaluated by pediatric nephrology in a multidisciplinary survivorship clinic. STUDY DESIGN: Retrospective chart review of all patients followed up by nephrology in our multidisciplinary survivorship clinic from August 2013 to June 2021. Data included clinic blood pressure, longitudinal ambulatory blood pressure monitoring (ABPM), echocardiography, serum creatinine, and first-morning urine protein/creatinine ratios. For patients with multiple ABPMs, results of initial and most recent ABPMs were compared. RESULTS: Of 422 patients followed in the multidisciplinary cancer survivorship clinic, 130 were seen by nephrology. The median time after therapy completion to first nephrology visit was 8 years. The most common diagnoses were leukemia/myelodysplastic syndrome (27%), neuroblastoma (24%), and Wilms tumor (15%). At the last follow-up, 68% had impaired kidney function, 38% had a clinical diagnosis of hypertension, and 12% had proteinuria. There were 91 ABPMs performed in 55 (42%) patients. Patients with multiple ABPMs (n = 21) had statistically significant reductions in overall median blood pressure loads: systolic initial load 37% vs most recent 10% (P = .005) and diastolic load 36% vs 14% (P = .017). Patients with impaired kidney function were more likely to have received ifosfamide. Patients with hypertension were more likely to have received total body irradiation or allogeneic stem cell transplant. CONCLUSIONS: History of leukemia/myelodysplastic syndrome, neuroblastoma, and Wilms tumor was frequent among survivors seen by nephrology. There was significant improvement in cardiovascular measures with increased recognition of hypertension and subsequent treatment.

Wilms tumor in children: A multivariate analysis of prognostic factors, with emphasis on inferior vena cava/right atrium extension. Results from a single-center study.

BACKGROUND: To identify prognostic factors for overall survival through the analysis of 132 patients with Wilms tumor followed at a single center, with emphasis on the inferior vena cava/right atrium extension. METHODS: Retrospective analysis of overall survival using logistic regression models and including age, sex, clinical features, associated syndromes, comorbidities, tumor size before chemotherapy, stage, presence of metastatic disease and its site, invasion of adjacent structures, inferior vena cava/right atrium extension, laterality, tumor histology, chemotherapy protocol, and radiotherapy as potential risk factors. RESULTS: From January 2000 through November 2021, 132 patients met the inclusion criteria, 64 females and 68 males; 15 (11.4%) patients presented with tumoral extension to inferior vena cava/right atrium and 44 had metastatic disease (33.3%). Based on logistic regression, the factors correlating to a fatal outcome were male sex (p = 0.046), high risk histology (p = 0.036), and the presence of metastatic disease (p = 0.003). None of the patients presenting inferior vena cava/right atrium extension died (p = 0.992). In a specific analysis of metastatic sites, hepatic metastasis alone showed correlation with a fatal outcome (p = 0.001). CONCLUSION: These results underline the importance of identifying and treating metastatic disease and high-risk tumors. The female gender as a potential driver for a less aggressive disease is a new finding that deserves further investigation. The accurate identification of inferior vena cava/right atrium extension, subsequent preoperative chemotherapy, and resection with a skilled team promoted survival rates of all patients. LEVEL OF EVIDENCE: II.

Sobrecrecimiento lateral aislado - caracterización auxológica y clínico-radiológica de una cohorte de 76 casos de un único centro / Isolated lateralized overgrowth: clinical, radiological, and auxological characteristics of a single-site cohort of 76 cases

Introducción. El sobrecrecimiento lateral aislado (SLA), antes denominado hemihiperplasia/ hemihipertrofia, se refiere al sobrecrecimiento corporal lateral en ausencia de un patrón reconocible de malformaciones o síndromes genéticos. El objetivo fue analizar el crecimiento y las características clínico-radiológicas de pacientes con SLA en seguimiento en un hospital de tercer nivel en Argentina entre 1993 y 2020. Población y métodos. Estudio retrospectivo, observacional, de una cohorte de pacientes con SLA. Resultados. Se incluyeron 76 casos, 41 varones. Mediana de años de seguimiento: 5,85 (rango intercuartílico [RIC] 2,60-10,96), máximo 15,76 años. Cuarenta y ocho de 76 pacientes presentaron sobrecrecimiento en más de un segmento corporal (SLA complejo). El puntaje Z promedio de peso al nacer de niñas de término con SLA complejo fue +0,51 (desviación estándar [DE] 0,91) (p 0,022). El crecimiento en estatura de la mayoría de los niños se ubicó entre los centilos 50 y 97 de la población de referencia. La mediana de asimetría de longitud de miembros inferiores fue 1,5 cm (RIC 1,01-2,2) en pacientes con tratamiento médico y 3,70 cm (RIC 2,953,98 cm) en aquellos que requiriero epifisiodesis. El 75 % mostró una progresión de la asimetría menor o igual a 2 cm. Ocho casos presentaron asimetría renal mayor o igual a 1 cm; 2 casos presentaron nefroblastoma: edad promedio al diagnóstico 0,75 años. Conclusiones. El crecimiento prenatal de niños con SLA es normal, excepto en niñas con SLA complejo en quienes tiende a estar aumentado. La estatura promedio se ubica en centilos altos con crecimiento normal. Se recomienda realizar cribado de tumores embrionarios en este grupo de niños.

Introduction. Isolated lateralized overgrowth (ILO), formerly referred to as hemihyperplasia/hemihypertrophy, is the overgrowth of one-half of the body to its contralateral in the absence of a recognizable pattern of malformations or genetic syndromes. Our objective was to analyze the growth clinical and radiological characteristics of patients with ILO under follow-up in a tertiary care hospital in Argentina between 1993 and 2020. Population and methods. Retrospective, observational, single cohort study of patients with ILO. Results. A total of 76 cases were included; 41 were males. Median years of follow-up: 5.85 (interquartile range [IQR]: 2.60­10.96), maximum: 15.76 years. Forty-eight of 76 patients had overgrowth compromising more than 1 body segment (complex ILO). The mean birth weight Z-score of term girls with complex ILO was +0.51 (standard deviation [SD]: 0.91) (p 0.022). Most children grew between the 50th and 97th centile of the Argentinian population height reference. The median leg length discrepancy was 1.5 cm (IQR: 1.01­2.2) in patients receiving medical treatment and 3.70 cm (IQR: 2.95­3.98 cm) in those who required epiphysiodesis. Progression of discrepancy ≤ 2 cm was observed in 75% of cases. Renal asymmetry ≥ 1 cm was observed in 8 cases; Wilms tumor was noted in 2 cases: mean age at diagnosis: 0.75 years. Conclusions. Prenatal growth of children with ILO is normal, except in girls with complex ILO, in whom it tends to be increased. The average height of boys and girls tends to be located in high centiles with normal growth over time. Embryonal tumor screening is recommended in this group of children.

Isolated lateralized overgrowth: clinical, radiological, and auxological characteristics of a single-site cohort of 76 cases. / Sobrecrecimiento lateral aislado - caracterización auxológica y clínico-radiológica de una cohorte de 76 casos de un único centro.

INTRODUCTION: Isolated lateralized overgrowth (ILO), formerly referred to as hemihyperplasia/hemihypertrophy, is the overgrowth of one-half of the body to its contralateral in the absence of a recognizable pattern of malformations or genetic syndromes. Our objective was to analyze the growth clinical and radiological characteristics of patients with ILO under follow-up in a tertiary care hospital in Argentina between 1993 and 2020. POPULATION AND METHODS: Retrospective, observational, single cohort study of patients with ILO. RESULTS: A total of 76 cases were included; 41 were males. Median years of follow-up: 5.85 (interquartile range [IQR]: 2.60-10.96), maximum: 15.76 years. Forty-eight of 76 patients had overgrowth compromising more than 1 body segment (complex ILO). The mean birth weight Z-score of term girls with complex ILO was +0.51 (standard deviation [SD]: 0.91) (p 0.022). Most children grew between the 50th and 97th centile of the Argentinian population height reference. The median leg length discrepancy was 1.5 cm (IQR: 1.01-2.2) in patients receiving medical treatment and 3.70 cm (IQR: 2.95-3.98 cm) in those who required epiphysiodesis. Progression of discrepancy ≤ 2 cm was observed in 75% of cases. Renal asymmetry ≥ 1 cm was observed in 8 cases; Wilms tumor was noted in 2 cases: mean age at diagnosis: 0.75 years. CONCLUSIONS: Prenatal growth of children with ILO is normal, except in girls with complex ILO, in whom it tends to be increased. The average height of boys and girls tends to be located in high centiles with normal growth over time. Embryonal tumor screening is recommended in this group of children.

Introducción. El sobrecrecimiento lateral aislado (SLA), antes denominado hemihiperplasia/hemihipertrofia, se refiere al sobrecrecimiento corporal lateral en ausencia de un patrón reconocible de malformaciones o síndromes genéticos. El objetivo fue analizar el crecimiento y las características clínico-radiológicas de pacientes con SLA en seguimiento en un hospital de tercer nivel en Argentina entre 1993 y 2020. Población y métodos. Estudio retrospectivo, observacional, de una cohorte de pacientes con SLA. Resultados. Se incluyeron 76 casos, 41 varones. Mediana de años de seguimiento: 5,85 (rango intercuartílico [RIC] 2,60-10,96), máximo 15,76 años. Cuarenta y ocho de 76 pacientes presentaron sobrecrecimiento en más de un segmento corporal (SLA complejo). El puntaje Z promedio de peso al nacer de niñas de término con SLA complejo fue +0,51 (desviación estándar [DE] 0,91) (p 0,022). El crecimiento en estatura de la mayoría de los niños se ubicó entre los centilos 50 y 97 de la población de referencia. La mediana de asimetría de longitud de miembros inferiores fue 1,5 cm (RIC 1,01-2,2) en pacientes con tratamiento médico y 3,70 cm (RIC 2,95- 3,98 cm) en aquellos que requirieron epifisiodesis. El 75 % mostró una progresión de la asimetría menor o igual a 2 cm. Ocho casos presentaron asimetría renal mayor o igual a 1 cm; 2 casos presentaron nefroblastoma: edad promedio al diagnóstico 0,75 años. Conclusiones. El crecimiento prenatal de niños con SLA es normal, excepto en niñas con SLA complejo en quienes tiende a estar aumentado. La estatura promedio se ubica en centilos altos con crecimiento normal. Se recomienda realizar cribado de tumores embrionarios en este grupo de niños.

International Comparisons of Clinical Demographics and Outcomes in the International Society of Pediatric Oncology Wilms Tumor 2001 Trial and Study.

PURPOSE: International comparisons of patient demographics, tumor characteristics, and survival can shed light on areas for health care system improvement. The International Society of Pediatric Oncology Wilms Tumor 2001 trial/study registered patients through national clinical study groups in Western Europe and Brazil. This retrospective post hoc analysis of the International Society of Pediatric Oncology Wilms Tumor 2001 database aims to make visible and suggest reasons for any variations in outcomes. METHODS: All patients with unilateral Wilms tumor (WT), age > 6 months, treated with preoperative chemotherapy as per protocol, and registered between 2001 and 2011 were eligible. Countries were grouped to give comparable case numbers and geographical representation. Cox univariable and multivariable (MVA) statistics were applied, with the German collaborative group (Gesellschaft für Pädiatrische Onkologie und Hämatologie-Austria, Germany, and Switzerland) as reference for hazard ratios for event-free survival (EFS) and overall survival (OS). RESULTS: A total of 3,176 eligible patients were registered from 24 countries assigned into six groups. Age and histologic risk group distribution were similar across all groupings. The distribution of WT stage varied by country grouping, with 14.9% (range, 11.1%-18.2%) metastatic at diagnosis. Median follow-up was 78.9 months. For localized WT, 5-year EFS varied from 80% (Brazilian group) to 91% (French group; P < .0001), retaining significance only for Brazil in MVA (P = .001). Five-year OS varied from 89% (Brazilian group) to 98% (French group; P < .0001). In MVA, only superior OS in France was significant (P = .001). Five-year EFS/OS for stage IV did not vary significantly. High-risk histology and tumor volume at surgery were significantly associated with increased risk of death in MVA for metastatic disease. CONCLUSION: International benchmarking of survival rates from WT within a large trial/study database has demonstrated statistically significant differences. Clinical interpretation should take account of variation in tumor stage but also treatment factors.

Suprahepatic Cava Thrombus Due to Wilms Tumor: Technique Without Cardiopulmonary Bypass.

Wilms tumor is a frequent malignant neoplasia in pediatric population. Extension to the inferior vena cava is a complication that occurs in approximately 4%-15% of cases. Surgical techniques derived from the field of adult transplant surgery allow the resection of the tumor with its thrombus extension. In the case of a 6-year-old male patient with a stage III Wilms tumor that originated from the left renal vein, thrombectomy and left radical nephroureterectomy were accomplished without extracorporeal circulation. Surgical technique applied in adult transplant surgery for removal of advanced renal tumors, could be a safe and feasible technique in pediatric population.

Bilateral Wilms' tumor in a child with Denys-Drash syndrome: novel frameshift variant disrupts the WT1 nuclear location signaling region.

OBJECTIVES: Wilm's Tumor (WT) is the most common pediatric kidney cancer. Whereas most WTs are isolated, approximately 5% are associated with syndromes such as Denys-Drash (DDS), characterized by early onset nephropathy, disorders of sex development and predisposition to WT. CASE PRESENTATION: A 46,XY patient presenting with bilateral WT and genital ambiguity without nephropathy was heterozygous for the novel c.851_854dup variant in WT1 gene sequence. This variant affects the protein generating the frameshift p.(Ser285Argfs*14) that disrupts a nuclear localization signal (NLS) region. CONCLUSIONS: This molecular finding is compatible with the severe scenario regarding the Wilm's tumor presented by the patient even though nephropathy was absent.

Genitourinary Tract Tumors in Children: An Update.

BACKGROUND: Genitourinary tract tumors in children are less common than in adults. Most of these tumors have different genetic backgrounds, clinical presentation, and oncologic behavior than their adult counterpart. As a result of low prevalence in children, some of the treatment approaches and recommendations are based on treatment experience in adult patients. However, thanks to scientific and technological development, survival rates have risen considerably. OBJECTIVE: This paper presents a review of the principal features of the tumors involving the genitourinary tract in children and an update in genetic background, diagnosis, and treatment. METHODS: A narrative review was performed on published literature about genitourinary tract tumors in pediatric patients. Papers presented in English and Spanish literature were reviewed. PubMed, Science Direct, and SciELO databases were used to collect information and present this article. RESULTS: Kidney tumors are the most common type of genitourinary tumors in children. Among those, Wilms tumor represents the majority of cases and shows the successful work of clinical trial groups studying this tumor type. Other tumors involving the genitourinary tract in children include Rhabdomyosarcoma, Transitional cell carcinoma, Testicular, and Adrenal tumors. CONCLUSION: Genitourinary tract tumors in children represent significant morbidity and economic burden, so awareness in early diagnosis represents improvement in treatment, clinical, and oncological outcomes.

WT1 Pathogenic Variants are Associated with a Broad Spectrum of Differences in Sex Development Phenotypes and Heterogeneous Progression of Renal Disease.

Wilms' tumor suppressor gene 1 (WT1) plays an essential role in urogenital and kidney development. Heterozygous germline pathogenic allelic variants of WT1 have been classically associated with Denys-Drash syndrome (DDS) and Frasier syndrome (FS). Usually, exonic pathogenic missense variants in the zinc finger region are the cause of DDS, whereas pathogenic variants affecting the canonic donor lysine-threonine-serine splice site in intron 9 cause FS. Phenotypic overlap between WT1 disorders has been frequently observed. New WT1 variant-associated phenotypes, such as 46,XX testicular/ovarian-testicular disorders of sex development (DSD) and primary ovarian insufficiency, have been reported. In this report, we describe the phenotypes and genotypes of 7 Brazilian patients with pathogenic WT1 variants. The molecular study involved Sanger sequencing and massively parallel targeted sequencing using a DSD-associated gene panel. Six patients (5 with a 46,XY karyotype and 1 with a 46,XX karyotype) were initially evaluated for atypical genitalia, and a 46,XY patient with normal female genitalia sought medical attention for primary amenorrhea. Germ cell tumors were identified in 2 patients, both with variants affecting alternative splicing of WT1 between exons 9 and 10. Two pathogenic missense WT1 variants were identified in two 46,XY individuals with Wilms' tumors; both patients were <1 year of age at the time of diagnosis. A novel WT1 variant, c.1453_1456 (p.Arg485Glyfs*14), was identified in a 46,XX patient with testicular DSD. Nephrotic proteinuria was diagnosed in all patients, including 3 who underwent renal transplantation after progressing to end-stage kidney disease. The expanding phenotypic spectrum associated with WT1 variants in XY and XX individuals confirms their pivotal role in gonadal and renal development as well as in tumorigenesis, emphasizing the clinical implications of these variants in genetic diagnosis.

Abordaje mínimamente invasivo del tumor de Wilms unilateral: un reporte de caso y revisión de la literatura / Minimally invasive approach to unilateral Wilms tumor: a case report and literature review

Introducción. El tumor de Wilms es la neoplasia abdominal más común en pacientes pediátricos. En la mayoría de los casos se presenta como una masa unilateral indolora en el abdomen. El objetivo de este artículo fue presentar el caso de una paciente de 4 años con tumor de Wilms unilateral derecho manejado con cirugía mínimamente invasiva en el Hospital Universitario del Valle. Métodos. Revisión de la historia clínica e imágenes de la paciente, descripción de la técnica quirúrgica y revisión de la literatura del manejo de tumor de Wilms unilateral. Caso clínico. Paciente femenina de 4 años quien consultó en abril de 2019 por un cuadro clínico de dolor abdominal y sensación de masa en flanco derecho. Se realizó ecografía abdominal donde se encontró imagen nodular heterogénea de contornos definidos en riñón derecho, con riñón izquierdo normal. Se hizo diagnóstico de tumor de Wilms unilateral y se llevó a cirugía mediante abordaje mínimamente invasivo, con buena evolución postoperatoria. Conclusión. La cirugía es el pilar del manejo, y la nefrectomía mediante abordaje laparoscópico para casos seleccionados, en manos entrenadas, tiene la suficiente eficacia, seguridad y cumplimiento de los principios quirúrgicos y oncológicos que provee la cirugía abierta.

Introduction. Wilms tumor is the most common abdominal neoplasm in pediatric patients. In most cases it presents as a painless unilateral mass in the abdomen. The objective of this article was to present the case of a 4-year-old patient with right unilateral Wilms tumor managed with minimally invasive surgery at the Hospital Universitario del Valle. Methods. Review of the patient's clinical history and images, description of the surgical technique and review of the literature on the management of unilateral Wilms tumor.Clinical case. A 4-year-old female patient who consulted on April 4, 2019 with a clinical presentation of abdominal pain and sensation of mass in the right flank. Abdominal ultrasound was performed where a heterogeneous nodular image of defined contours was found in the right kidney, with a normal left kidney. A diagnosis of unilateral Wilms tumor was made and surgery was carried out using a minimally invasive approach, with good postoperative evolution. Conclusion. Wilms tumor is the most common abdominal neoplasm in pediatric patients. The most common presentation is a painless palpable mass. Surgery is the mainstay of management, and nephrectomy using a laparoscopic approach for selected cases, in trained hands, has sufficient efficacy, safety, and compliance with surgical and oncological principles that open surgery provides.

Non-coding RNAs in Wilms' tumor: biological function, mechanism, and clinical implications.

Non-coding RNAs are involved with maintenance and regulation of physiological mechanisms and are involved in pathological processes, such as cancer. Among the small ncRNAs, miRNAs are the most explored in tumorigenesis, metastasis development, and resistance to chemotherapy. These small molecules of ~ 22 nucleotides are modulated during early renal development, involved in the regulation of gene expression and Wilms' tumor progression. Wilms' tumors are embryonic tumors with few mutations and complex epigenetic dysregulation. In recent years, the small ncRNAs have been explored as potentially related both in physiological development and in the tumorigenesis of several types of cancer. Besides, genes regulated by miRNAs are related to biological pathways as PI3K, Wnt, TGF-ß, and Hippo signaling pathways, among others, which may be involved with the underlying mechanisms of resistance to chemotherapy, and in this way, it has emerged as potential targets for cancer therapies, including for Wilms' tumors.

Kidney Outcomes and Hypertension in Survivors of Wilms Tumor: A Prospective Cohort Study.

OBJECTIVE: To assess the prevalence of therapy-related kidney outcomes in survivors of Wilms tumor (WT). STUDY DESIGN: This prospective cohort study included survivors of WT who were ≥5 years old and ≥1 year from completing therapy, excluding those with preexisting hypertension, prior dialysis, or kidney transplant. Participants completed 24-hour ambulatory blood pressure monitoring (ABPM). Abnormal blood pressure (BP) was defined as ≥90th percentile. Masked hypertension was defined as having normal office BP and abnormal ABPM findings. Urine was analyzed for kidney injury molecule-1, interleukin-18, epidermal growth factor, albumin, and creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the bedside chronic kidney disease in children equation. Recent kidney ultrasound examinations and echocardiograms were reviewed for contralateral kidney size and left ventricular hypertrophy, respectively. Clinical follow-up data were collected for approximately 2 years after study enrollment. RESULTS: Thirty-two participants (median age, 13.6 years [IQR, 10.5-16.3 years]; 75% stage 3 or higher WT) were evaluated at a median of 8.7 years (IQR, 6.5-10.8 years) after therapy; 29 participants underwent unilateral radical nephrectomy, 2 bilateral partial nephrectomy, and 1 radical and contralateral partial nephrectomy. In this cohort, 72% received kidney radiotherapy and 75% received doxorubicin. Recent median eGFR was 95.6 mL/min/1.73 m2 (IQR, 84.6-114.0; 11 [34%] had an eGFR of <90 mL/min/1.73 m2). Abnormal ABPM results were found in 22 of 29 participants (76%), masked hypertension in 10 of 29 (34%), and microalbuminuria in 2 of 32 (6%). Of the 32 participants, 22 (69%) had abnormal epidermal growth factor; few had abnormal kidney injury molecule-1 or interleukin-18. Seven participants with previous unilateral nephrectomy lacked compensatory contralateral kidney hypertrophy. None had left ventricular hypertrophy. CONCLUSIONS: In survivors of WT, adverse kidney outcomes were common and should be closely monitored.

Tumor de Wilms estádio IV: desafio terapêutico / [Wilms' tumor stage IV: therapeutic challenge]

Tumor de Wilms (TW) é a neoplasia maligna primária renal mais comum na infância alcançando taxa de cura de até 90%. No entanto, em países em desenvolvimento, a sobrevida global relatada para TW varia de 50% a 89%. Nesses países, vários desafios são encontrados. Dentre eles, podemos citar a dificuldade de acesso aos serviços especializados no tratamento adequado e cuidados de suporte, desnutrição, recusa e abandono ao tratamento, crença em tratamentos alternativos, analfabetismo e falta de apoio social. Em consequência, muitos pacientes chegam aos serviços especializados apresentando a doença em estádio avançado (estádio III e IV) o que diminui substancialmente a taxa de sobrevivência. Estudos relatam que pacientes com doença metastática compreendem 15 a 17% dos casos. Assim, este estudo visa fazer uma revisão bibliográfica sobre tumor de Wilms unilateral e em particular sobre o estádio IV

Wilms' tumor (WT) is the most common primary renal malignancy in childhood, reaching a cure rate of up to 90%. However, in developing countries the overall survival reported for WT ranges from 50% to 89%. In these countries, several challenges are found. Among them, we can mention the difficulty in accessing specialized services in adequate treatment and supportive care, malnutrition, refusal and abandonment of treatment, belief in alternative treatments, illiteracy and lack of social support. As result, many patients arrive at specialized services presenting the disease in an advanced stage (stages III and IV), which substantially decreases the survival rate. Studies report that patients with metastatic disease comprise 15 to 17% of cases. So, this study aims to perform a literature review on unilateral Wilms' tumor and, particularly, on stage IV