Nephroblastoma, also referred to as Wilms tumor, is the fifth most common malignancy in childhood and the most frequent renal tumor in the pediatric population [1] [2]. Additionally, its peak incidence is in early childhood between the ages of 3 to 4 [3]. Patients with trisomies 13 and 18, Beckwith-Wiedemann syndrome, and Drash syndrome are at risk for developing this tumor [3]. Due to advances in treatment, the survival rate is 80% to 90%.

Regarding the presentation, the majority of patients will have an asymptomatic abdominal mass [4] [5] while some will also develop manifestations such as malaise, abdominal pain, hematuria, and hypertension [5]. The mass may be discovered incidentally or during a workup following trauma, hematuria, or hypertension [4]. In rare cases, the tumor ruptures and causes fever, pain, and anemia [5]. Furthermore, respiratory symptoms are present in those with metastasis to the lungs.

Nephroblastoma adheres to the "rules of 10s," which relates that 10% of these cases are bilateral, 10% develop vascular invasion, 10% exhibit lung metastasis at initial presentation, 10% have histology suggestive of poor outcome, and 10% demonstrate calcifications on imaging [6].

Complications

There are adverse effects associated with various types of treatment. For example, radiation therapy poses danger to the remaining kidney while chemotherapy agents are harmful to the liver and other organs. Also, removal of one kidney will lead t0 hypertrophy of the remaining kidney.

Physical exam

Remarkable findings include an abdominal mass, which should be palpated carefully to avoid rupture. Other notable features will be those of associated syndromes.

• Splenomegaly

  It is also important to investigate “B” symptoms associated with any lymphadenopathy or splenomegaly. Laboratory tests can often be helpful in ambiguous cases. [aafp.org]

• Fever

  A six-month-old girl with persistent high fevers was found to have pyuria and bacteriuria. Ultrasonography revealed multilocular cysts in the right kidney. Right nephrectomy was performed with cyst wall rupture during surgery. [ncbi.nlm.nih.gov]

  Doctors don’t know what causes Wilms tumor, but children who have certain health problems at birth are more likely to get it Children with Wilms tumor have a lump in their belly and may throw up and have belly pain, fever, poor appetite, and upset stomach [merckmanuals.com]

  Later, symptoms may indicate fever, distortion of the kidney mass, evidence of secondary tumours elsewhere in the body, abdominal and flank pain, weight loss, nausea, loss of appetite, and vomiting. [britannica.com]

  In rare cases, the tumor ruptures and causes fever, pain, and anemia. Furthermore, respiratory symptoms are present in those with metastasis to the lungs. [symptoma.com]

• Anemia

  겸상적혈구빈혈(sickle cell anemia),                     선천혈구감소성빈혈(congenital thrombocytopenic anemia, CDA), 판코니빈혈(Fanconi anemia),                     지중해빈혈(thalassemia), 무거대핵세포혈소판감소증(amegakaryocytic thrombocytopenia) 등 선천성 대사질환 헐러증후군(Hurler syndrome) 등 선천성 [lifeline.co.kr]

  In rare cases, the tumor ruptures and causes fever, pain, and anemia. Furthermore, respiratory symptoms are present in those with metastasis to the lungs. [symptoma.com]

  Patients sometimes experience abdominal pain (around 10% of cases), hypertension, fever (20% of cases), hematuria and anemia. [orpha.net]

  Tumor Children diagnosed with kidney tumors may have experienced the some following symptoms: A lump or mass in the abdomen of an otherwise well child Abdominal pain Blood in the urine High blood pressure Fever Diarrhea Weight loss Urogenital infections Anemia [curesearch.org]

• Weight Loss

  Later, symptoms may indicate fever, distortion of the kidney mass, evidence of secondary tumours elsewhere in the body, abdominal and flank pain, weight loss, nausea, loss of appetite, and vomiting. [britannica.com]

  Each patient presented with a large, rapidly growing, abdominal mass (average duration of symptoms, less than 2 months), had no constitutional symptoms (e.g., weight loss, fever), and otherwise were healthy (80%). [ajronline.org]

  loss Urogenital infections Anemia Shortness of breath A general feeling of being tired and unwell Nausea and vomiting News About Wilms Tumor [curesearch.org]

• Fatigue

  […] tumor is first detected as a painless lump in the abdomen, found by a parent or by a pediatrician during a routine check-up, although it may be accompanied by symptoms such as blood in the urine, anemia (which may be accompanied by unusual bleeding or fatigue [columbiadoctors.org]

  Prepare child and family for fatigue during recovery from surgery and with radiation treatments. Plan frequently rest periods between daily activities. [rnpedia.com]

  The therapy might result in side effects, e.g. diarrhea, fatigue, nausea, and skin irritation. [junisa.ru]

  Some children may have bloody urine, abdominal pain, loss of appetite, fatigue or weight loss. If a tumor is suspected in your child's abdomen, don't apply pressure to this area. [ucsfbenioffchildrens.org]

• Pallor

  Non-specific symptoms are present in less than 1/3 children: subfebrility, weakness, pallor, loss of appetite constipation, abdominal pain 10–30 % patients develop micro or macroscopic hematuria (sometimes only transient) due to tumor penetration and [telemedicina.med.muni.cz]

  Additional symptoms that should prompt concern include pallor, petechiae or ecchymoses, bone pain and significant weight loss. [aafp.org]

• Abdominal Pain

  We report a case of ERNB in a 4-year-old boy complaining of abdominal pain and vomiting. Imaging showed a retroperitoneal mass and left hydronephrosis. The mass was completely removed by surgery. [ncbi.nlm.nih.gov]

  Other children have abdominal pain or blood in the urine ( hematuria ). [healthanddisease.com]

  Regarding the presentation, the majority of patients will have an asymptomatic abdominal mass while some will also develop manifestations such as malaise, abdominal pain, hematuria, and hypertension. [symptoma.com]

  Findings Asymptomatic abdominal mass most common Abdominal pain Hematuria Hypertension Urinary tract infection Varicocele Aniridia Hemihypertrophy Beckwith-Wiedemann Syndrome Imaging Findings Ultrasound is frequently the first study Echogenic mass CT [learningradiology.com]

  Some patients with nephroblastoma experience abdominal pain, nausea, vomiting, high blood pressure or blood in the urine. [carehospitals.com]

• Abdominal Mass

  Regarding the presentation, the majority of patients will have an asymptomatic abdominal mass while some will also develop manifestations such as malaise, abdominal pain, hematuria, and hypertension. [symptoma.com]

  Nephroblastoma must be included in the differential diagnosis of hypertension associated with increased renin concentrations, even in the absence of an abdominal mass. [ncbi.nlm.nih.gov]

• Nausea

  The therapy might result in side effects, e.g. diarrhea, fatigue, nausea, and skin irritation. [junisa.ru]

  Later, symptoms may indicate fever, distortion of the kidney mass, evidence of secondary tumours elsewhere in the body, abdominal and flank pain, weight loss, nausea, loss of appetite, and vomiting. [britannica.com]

  Some patients with nephroblastoma experience abdominal pain, nausea, vomiting, high blood pressure or blood in the urine. [carehospitals.com]

• Abdominal Distension

  Abdominal distension was the most common clinical presentation (Figure 1). Discussion The Wilms tumor or Nephroblastoma is the commonest childhood cancer in Rwanda. [panafrican-med-journal.com]

• Pelvic Mass

  While the condition is extremely rare, it should be included in the differential diagnosis of a young child with bilateral renal pelvic masses. [ncbi.nlm.nih.gov]

• Hepatomegaly

  Clinical Features• Opsoclonus-Myoclonus: " dancing eyes, dancing feet syndrome"—better prognosis 4%• Cervical involvement: - Horners syndromeThorax:- Respiratory distress• Abdomen: - Hard mass, fixed, abdominal Discomfort, Massive hepatomegaly 10. [slideshare.net]

  Beckwith-Wiedemann syndrome: 4–10% risk for Wilms tumor, excessive growth at the cellular level, organ level (macroglossia, nephromegaly, hepatomegaly) or body segment level (hemihypertrophy), WT2 mutations (see below). [urology-textbook.com]

  VOD is primarily a clinical diagnosis characterized by hepatomegaly or pain in the right upper quadrant, jaundice, ascites, and unexplained weight gain. [emedicine.medscape.com]

• Hepatosplenomegaly

  Leukemia should be suspected if persistent vague symptoms are accompanied by evidence of abnormal bleeding, bone pain, lymphadenopathy or hepatosplenomegaly. [aafp.org]

  Affected males typically have intellectual disability, macrosomia, cardiac, skeletal, gastrointestinal and genitourinary anomalies, hepatosplenomegaly, and distinctive facial features that include macrocephaly, macrostomia (large, wide mouth), and macroglossia [invitae.com]

• Hypertension

  An infant with severe hypertension who had a nephroblastoma which was secreting active renin is described. [ncbi.nlm.nih.gov]

  The mass may be discovered incidentally or during a workup following trauma, hematuria, or hypertension. In rare cases, the tumor ruptures and causes fever, pain, and anemia. [symptoma.com]

• Aniridia

  Sporadic aniridia mutations may affect the WT1 region adjacent to the AN2 aniridia region, causing a kidney cancer called nephroblastoma (Wilms tumor). [diki.pl]

  Deletional analysis of individuals with the WAGR syndrome (for, Wilms' tumour, aniridia, genitourinary abnormalities and mental retardation) showed that a Wilms' tumour gene lies at chromosomal position 11p13. [ncbi.nlm.nih.gov]

  The commonest of these are hemihypertrophy, Aniridia, genitary urinary abnormalities and Beckwith Weidemann syndrome. [health24.com]

• Hematuria

  The mass may be discovered incidentally or during a workup following trauma, hematuria, or hypertension. In rare cases, the tumor ruptures and causes fever, pain, and anemia. [symptoma.com]

  Large tumor size and gross hematuria were associated with risk of a poorer outcome. [ncbi.nlm.nih.gov]

  Urine specimens show hematuria; no increase in vanillylmandelic acid and homovanillic acid levels as occurs with neuroblastoma. [rnpedia.com]

  movement of the mass during respiration, looking for signs of overgrowth, peripheral lymph nodes, edemas, hypertension, passing stool/urine, macroscopic hematuria. [telemedicina.med.muni.cz]

  […] children Both kidneys affected synchronously or metachronously in 5-10% Peak incidence at 2.5-3 years More common in blacks than whites with an approximately equal gender distribution Clinical Findings Asymptomatic abdominal mass most common Abdominal pain Hematuria [learningradiology.com]

• Macroscopic Hematuria

  movement of the mass during respiration, looking for signs of overgrowth, peripheral lymph nodes, edemas, hypertension, passing stool/urine, macroscopic hematuria. [telemedicina.med.muni.cz]

Any child with an abdominal mass warrants a full workup consisting of a patient and family history, complete physical exam, and the appropriate studies.

Laboratory tests

The clinician must obtain a complete blood count (CBC), complete metabolic panel (CMP) including renal function tests, and a coagulation panel. Urinalysis is also important.

Cytogenetic testing

Chromosomal analysis for associated syndromes is indicated.

Imaging

Ultrasonography of the kidneys is the initial diagnostic modality since it is widely available, inexpensive, and safe. Renal ultrasonography determines the location and characteristic of the mass as it differentiates solid from cystic lesions [5]. This study also detects thrombi in the inferior vena cava (IVC).

Abdominal computed tomography (CT) scan provides critical details regarding the tumor's origin, vascular and lymph nodal invasion, bilateral renal involvement, and metastatic disease [7]. Moreover, CT with contrast enhancement demonstrates a greater sensitivity for vascular involvement [8].

Experts advocate that contrast-enhanced magnetic resonance imaging (MRI) is the preferred diagnostic study [3]. This modality exhibits the most sensitivity for ascertaining caval patency and invasion. Generally, a nephroblastoma has low signal intensity on a T1 weighted image and high intensity on T2 [9].

Chest radiography and CT scan are performed to investigate lung metastasis.

Histology

The diagnosis is confirmed by histologic analysis of the tumor, which is characterized by epithelial, stromal, and blastemal embryonic elements [4]. Very importantly, histology also determines the prognosis [10].

[…] leading to precise diagnoses and the selection of the optimal treatment. [ncbi.nlm.nih.gov]

These studies have rigorously compared treatment regimens (treatment plans), and helped define the optimal treatment for each stage and type of Wilms tumor. [danafarberbostonchildrens.org]

In a multivariate analysis, PDGF-α protein expression by epithelial cells was an independent prognostic marker of a favourable prognosis. [ncbi.nlm.nih.gov]

Prognosis In the majority of cases, the prognosis is favorable with a survival rate of over 90%. [orpha.net]

Very importantly, histology also determines the prognosis. [symptoma.com]

Etiology of Wilms' tumor (nephroblastoma) : mutations of WT1 gene on chromosome 11 and nephroblastematosis (persistence of renal blastema in kidney tissue). Wilms' tumor (nephroblastoma). [pathologyatlas.ro]

The etiology of Wilms tumor, an embryonic kidney tumor, is genetically heterogeneous. [ncbi.nlm.nih.gov]

Etiology Nephroblastoma is sporadic in 99% of cases and, among these cases, 10% are associated with congenital anomalies (aniridia, hemihypertrophy, genitourinary defects) or form part of specific syndromes (Beckwith-Wiedemann, Denys-Drash, WAGR or Perlman [orpha.net]

The National Wilms Tumor Study (NWTS) constitutes a unique resource for study of clinical, pathologic, and epidemiologic features of Wilms tumor (WT). [ncbi.nlm.nih.gov]

Summary Epidemiology The annual incidence is estimated at about 1/10,000 births and it affects boys as well as girls. [orpha.net]

The pathophysiology and clinical aspects of both tumours including associated risk factors and pathologies are discussed. [ncbi.nlm.nih.gov]

[…] including FNA) and removal of tumor in > 1 piece Stage IV (10%): Hematogenous metastases or spread beyond abdomen Stage V (5%): Bilateral renal involvement (substage each tumor separately according to above criteria) Reference: American Cancer Society Pathophysiology [pathologyoutlines.com]

Multicellular spheroid, which is an aggregated form of cells in a spherical shape, provides a relevant pathophysiological gradients of various chemicals that reflects the environment of tumors, since the 3D structure acts as a barrier against chemical [library.kaist.ac.kr]

Original Editors - Students from Bellarmine University's Pathophysiology of Complex Patient Problems project. [physio-pedia.com]

Adipose tissue, or more specifically visceral fat, which is located around the internal organs, plays a central role in the pathophysiology of metabolic syndrome. [journals.plos.org]

Simultaneous thoraco-abdominal surgery with total circulatory arrest is advocated to remove the cardiac and caval tumor together with the primary tumor in order to prevent sudden hemodynamic and embolic complications. [ncbi.nlm.nih.gov]

Prevention Wilms' tumor can't be prevented by anything you or your child can do. [mayoclinic.org]

Preventive measures Wilms' tumor can't be prevented. If the child has symptoms that increase the risk of Wilms' tumor, the doctor may suggest periodic kidney ultrasounds to look for kidney abnormalities. [junisa.ru]

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