What are the other Names for this Condition? (Also known as/Synonyms)

• Cystic Renal Hamartoma in Children
• Pediatric Multilocular Renal Cyst
• Renal Cystic Nephroma in Children

What is Cystic Nephroma in Children? (Definition/Background Information)

• Cystic nephroma of kidney is an uncommon, benign, cystic tumor that may be present in both children and adults. The tumor is usually single and affects one kidney. It can occasionally affect both kidneys
• The kidney consists of 2 zones; the cortex and the medulla. The cortex is the peripheral or outer portion of the kidney, and the medulla is the central or inner portion of the kidney. The tumor may be present in the cortex or medulla of the kidney
• Cystic Nephroma in Children is mostly observed in very young children (by or before age 4), typically affecting boys. The cause and risk factors for these tumors are not well-established, but the tumor formation may be due to genetic defects
• The signs and symptoms depend upon the size of the tumors. It may include blood in urine, abdominal pain, and frequent infections affecting the urinary tract system. Large tumors are even known to cause chronic kidney failure
• Typically, a surgical excision of Cystic Nephroma in Children with its entire removal is the treatment of choice. The prognosis is excellent with its complete removal, since it is a benign tumor

Who gets Cystic Nephroma in Children? (Age and Sex Distribution)

• Cystic Nephroma in Children mostly affects children below age 4 years (between 3 months to 4 years)
• Congenital cystic nephromas are also known to occur, when the tumor is observed in newborn children
• Many of these tumors affect boys more than girls
• No ethnic or racial preference is seen

What are the Risk Factors for Cystic Nephroma in Children? (Predisposing Factors)

Currently, no definitive risk factors have been noted for Cystic Nephroma in Children.

• Nevertheless, familial cases have been associated with pleuropulmonary blastomas
• A family history of cystic nephroma may be a risk factor

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one's chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Cystic Nephroma in Children? (Etiology)

The exact cause and mechanism of Cystic Nephroma in Children, in a majority of cases, is unknown. 

• The tumor may form due to mutations on the DICER1 gene, which have been detected in some tumors
• In general, in children, the cystic nephroma forms from nephrogenic rests (certain abnormal cell clusters)
• Some consider cystic nephroma to be a benign variant of cystic partially-differentiated nephroblastoma

What are the Signs and Symptoms of Cystic Nephroma in Children?

The signs and symptoms of Cystic Nephroma in Children depend on the size and location of the tumor. It can also vary from one child to another. In general, small tumors are asymptomatic and large tumors can cause signs and symptoms. The kidney symptoms may be caused due to mass effect (presence of bulky tumors).

The signs and symptoms of Cystic Nephroma in Children may include the following:

• Most of these tumors are sporadic and unilateral (affecting one kidney)
• Rarely, familial cases leading to bilateral presentation (affecting both kidneys) have been noted
• The tumor can affect the cortex (peripheral portion) or medulla (central portion) of the kidney
• It is often detected as an abdominal mass by parents or caretakers; abdominal swelling may be seen
• The average size of the tumor is about 9 cm
• It is often well-defined and demarcated
• It may be associated with urinary tract infections, blood in urine, increased blood pressure, and flank pain
• Large tumors can severely affect the functioning of the kidney that is involved. Tumors growing to larger sizes can cause compression of adjoining organs and structures, but are not known infiltrate into them

How is Cystic Nephroma in Children Diagnosed?

The diagnosis of Cystic Nephroma in Children may involve the following tests and procedures:

• Complete physical exam with evaluation of medical history
• Plain X-ray of the abdomen
• Ultrasound scan of the abdomen
• CT or CAT scan with contrast of the abdomen may show a well-defined mass. This radiological procedure creates detailed 3-dimensional images of structures inside the body
• MRI scan of the abdomen: Magnetic resonance imaging (MRI) uses a magnetic field to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor
• Urine analysis to check for the presence of blood cells
• Kidney function test
• Intravenous pyelogram (IVP): A dye is injected into the blood vessels and the image of kidney structure is obtained
• Vascular angiographic studies of the tumor

Invasive diagnostic procedures such as:

• Laparoscopy: A special device is inserted through a small hole into the abdomen, to visually examine it. If necessary, a tissue sample is obtained for further analysis. Exploration of the abdomen using a laparoscope is called ‘exploratory laparoscopy’
• Laparotomy: The abdomen is opened through an incision for examination, and if required, a biopsy sample obtained. Exploration of the abdomen using laparotomy procedure is called ‘exploratory laparotomy’

Although the above modalities can be used to make an initial diagnosis, a tissue biopsy of the tumor is necessary to make a definitive diagnosis to begin treatment. The tissue for diagnosis can be procured in multiple different ways which include:

• Fine needle aspiration (FNA) biopsy of the kidney tumor: A FNA biopsy may not be helpful, because one may not be able to visualize the different morphological areas of the tumor. Hence, a FNA biopsy as a diagnostic tool has certain limitations, and an open surgical biopsy is preferred
• Open biopsy of the kidney tumor

Tissue biopsy:

• A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
• Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
• Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

A differential diagnosis, to eliminate other tumor types is considered, before arriving at a definitive diagnosis. These include:

• Adult cystic nephroma
• Cystic partially-differentiated nephroblastoma
• Cystic renal dysplasia
• Wilms tumor

Note: A diagnosis is made after careful analysis of the tumor specimen and extensive sampling of tumor to rule out malignancy.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Cystic Nephroma in Children?

The complications of Cystic Nephroma in Children may include:

• Stress and anxiety due to a concern of kidney cancer
• If bleeding occurs in the tumor suddenly, it can cause retroperitoneal hemorrhage, which can result in large blood loss leading to severe shock. This is a potentially life-threatening complication requiring emergency care. In this situation, the signs and symptoms could be nausea, vomiting, back pain, sudden drop in blood pressure, and palpitations. This clinical condition is termed Wunderlich syndrome
• The presence of kidney cysts can cause kidney failure, due to compression of the kidney tissue
• Chronic renal failure affecting kidney function, if tumors are large; especially, when the condition is bilateral (affecting both the kidneys)
• Damage to the muscles, vital nerves, and blood vessels, during surgery
• Post-surgical infection at the wound site is a potential complication

Research has not conclusively proven that cystic nephroma tumors can turn malignant.

How is Cystic Nephroma in Children Treated?

The treatment measures for Cystic Nephroma in Children may include the following:

• Surgical intervention with complete excision can result in a cure. It can also help reduce the chances of tumor recurrence

The surgical treatment methods may include:

• Endoscopic surgery
• Nephron-sparing surgery
• Partial or complete nephrectomy
• Tumor embolization is a possible treatment option. Here the blood supply to the tumor is blocked resulting in its shrinkage or death
• Sclerotherapy to collapse the cyst may be effective in some cases. Multiple sessions of sclerotherapy may be needed

A partial or complete nephrectomy may be considered, when large-sized tumors are noted in the kidneys. 

• A kidney dialysis may be required, if the kidney function is severely compromised due to renal failure
• Prompt diagnosis and emergency treatment of any abdominal (retroperitoneal) bleeding due to the tumor should be immediately considered
• Postoperative care is important: A minimum activity level is ensured, until the surgical wound heals
• Follow-up care with regular screening may be recommended by the healthcare provider

How can Cystic Nephroma in Children be Prevented?

• Current medical research has not established a method of preventing Cystic Nephroma in Children
• Regular medical screening at periodic intervals with tests and physical examinations are strongly recommended

What is the Prognosis of Cystic Nephroma in Children? (Outcomes/Resolutions)

The prognosis of Cystic Nephroma in Children depends upon the severity of the signs and symptoms. It also depends upon the overall health of the individual.

• Typically, children with small-sized tumors have better prognoses than those with larger-sized tumors
• In most cases, the prognosis of small-sized solitary tumors is excellent with surgical intervention or appropriate treatment, since these are benign

Additional and Relevant Useful Information for Cystic Nephroma in Children:

• According to researchers, adult cystic nephroma is a tumor that is unrelated to its pediatric counterpart. Also, when this tumor is observed in adults, it affects females more than males (contrary to Pediatric Cystic Nephroma that is seen more often in boys)

Please visit our Cancer & Benign Tumors Health Center for more physician-approved health information:

http://www.dovemed.com/diseases-conditions/cancer/