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

  Your child is being treated for this condition and symptoms get worse or new symptoms develop, mainly cough, chest pain, weight loss, or persistent fevers. [medlineplus.gov]

  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]

  However, parents must watch for signs of problems, like fever, nausea, vomiting, or diarrhea. A child with a high fever should see a doctor right away. [kidshealth.org]

• Anemia

  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]

  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]

  Typically, the 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 [columbiadoctors.org]

  Tests include: Abdominal ultrasound Abdominal x-ray BUN Chest x-ray or CT scan Complete blood count (CBC), may show anemia Creatinine Creatinine clearance CT scan of the abdomen with contrast MRI Intravenous pyelogram MR angiography (MRA) Urinalysis Alkaline [mountsinai.org]

  Those include: blood in the urine anemia weight loss fever Risk Factors Most children develop Wilms’ tumor due to a random genetic mutation, not from an inherited genetic mutation. [mskcc.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]

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

  Your child is being treated for this condition and symptoms get worse or new symptoms develop, mainly cough, chest pain, weight loss, or persistent fevers. [medlineplus.gov]

  weight loss, fever), and otherwise were healthy (80%). Twenty-six patients had IV or retrograde pyelograms. Twenty-three showed a nonspecific mass effect. [ajronline.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]

  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]

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

  Children with Wilms’ tumor might display the following symptoms: constipation abdominal pain, swelling, or discomfort nausea and vomiting weakness and fatigue loss of appetite fever blood in their urine or discoloration of their urine high blood pressure [healthline.com]

  Wilms' tumor is characterized by: Abdominal swelling, often toward one side Fever Abdominal pain Constipation High blood pressure (hypertension) Large swollen veins across the abdomen Blood in the urine (hematuria) Fatigue Loss of appetite Weight loss [chop.edu]

• Wound Infection

  infection, hernia (4%) Vascular complications (2%) Splenic and intestinal injury (1.5%) Impaired renal function Bilateral Wilms tumor Approximately 5% of children with Wilms tumor will have bilateral involvement. [27] In these patients, the goals of [emedicine.com]

  Postoperative complications include intestinal obstruction (five percent), intussusception and wound infection. Children with retroperitoneal dissections are at increased risk of postoperative intussusception. [pedsurglibrary.com]

• Abdominal Mass

  Patients will typically have an asymptomatic abdominal mass although some will have other features as well. The prognosis is excellent due to advances in therapy. [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]

  Children who have Wilms tumor often present with an asymptomatic abdominal mass, found by caregivers or pediatricians. [pedsinreview.aappublications.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]

  Signs and Symptoms of Wilms 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 [curesearch.org]

  Symptoms may include any of the following: Abdominal pain Abnormal urine color Constipation Fever General discomfort or uneasiness ( malaise ) High blood pressure Increased growth on only one side of the body Loss of appetite Nausea and vomiting Swelling [medlineplus.gov]

• Nausea

  Possible side effects include nausea, tiredness, skin irritation, or diarrhea. Treatment regimens vary depending on the Wilms tumor stage Stage I or II cancer. [plusmedical.ro]

  However, parents must watch for signs of problems, like fever, nausea, vomiting, or diarrhea. A child with a high fever should see a doctor right away. [kidshealth.org]

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

• 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]

• 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]

• Hepatomegaly

  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]

  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]

• 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]

• Hepatic Mass

  Ultrasonography has a high sensitivity for detecting hepatic masses ( 92 ). [doi.org]

• Aniridia

  Patients with bilateral tumors, aniridia, cryptorchism/hypospadias, Beck-with-Wiedemann syndrome, or intralobar nephrogenic rests tend to be diagnosed much younger than average (median 17-27 months). [ncbi.nlm.nih.gov]

  Wilms' tumor occurs more frequently in children with certain abnormalities or syndromes present at birth, including: Aniridia. In aniridia (an-ih-RID-e-uh), the iris — the colored portion of the eye — forms only partially or not at all. [mayoclinic.org]

  Population-based risk estimates of Wilms tumor in sporadic aniridia. A comprehensive mutation screening procedure of PAX6 identifies 80% of mutations in aniridia. Hum. Genet. 2001; 109(1):11-8. PMID: 11479730 Muto, R, et al. [invitae.com]

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

• 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]

  Less frequent findings include abdominal pain, hematuria, fever, anorexia, nausea, and vomiting. Hematuria can be microscopic or gross. Hypertension may occur and is of variable severity. [msdmanuals.com]

  Constipation Fever General discomfort or uneasiness ( malaise ) High blood pressure Increased growth on only one side of the body Loss of appetite Nausea and vomiting Swelling in the abdomen ( abdominal hernia or mass ) Sweating (at night) Blood in urine (hematuria [medlineplus.gov]

• 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].

• Human Papillomavirus

  The human papillomavirus type 16 E6 and E7 oncoproteins cooperate to induce mitotic defects and genomic instability by uncoupling centrosome duplication from the cell division cycle. Proc Natl Acad Sci U S A 2000 ; 97 : 10002 –7. Saunders W. [doi.org]

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