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

• ERRT of the Genitourinary System
• ERRT of the Urogenital System
• Extrarenal Rhabdoid Tumor of the Urogenital System

What is Extrarenal Rhabdoid Tumor of the Genitourinary System? (Definition/Background Information)

• Extrarenal Rhabdoid Tumor (ERRT) of the Genitourinary System is a rare and highly malignant rhabdoid tumor (MRT) seen in the genitourinary tract; the genitourinary or urogenital system includes the urinary and genital organs
• The tumor can be seen anywhere in the urinary tract and pelvis, except in the kidney (hence termed extrarenal)

Incidence:

• A vast majority are seen before age 3; 80% are seen in infants and young children less than 2 years (average age 12 months)
• Extremely rare are congenital tumors
• Both males and females are affected
• All races and ethnic groups are at risk

Risk factors:

• Familial rhabdoid tumor predisposition syndrome type 1 is a known risk factor
• Other risk factors are not well-characterized

Cause:

• Malignant rhabdoid tumors (MRTs) show loss of SMARCB1 gene or frequent SMARCB1 genetic abnormalities
• MRTs are defined by the inactivation of SMARCB1 gene on the long arm of chromosome 22, at specific location q11.23 (involvement of both alleles are observed)
• The above inactivation may take place from genetic mutations and partial or complete loss of chromosome material
• Less than 5% of the individuals with MRT present biallelic inactivation of SMARCA4
• SMARCB1 mutations may occur in the germline in as many as one-third of patients; these patients are affected by the familial for of rhabdoid tumor predisposition syndrome (RTPS)
• The above-mentioned genetic abnormalities are thought to result in cancer development

Signs and symptoms:

• The tumors can arise in a variety of anatomical (urogenital) locations, excluding the kidney 
• Depending on the location of the tumor, the signs and symptoms can vary
• No specific signs and symptoms are generally noted, but large sizes present abdominal masses and obstructive symptoms
• Some tumors can grow to large sizes and be highly infiltrative showing bleeding and tumor necrosis

Diagnosis: A vast majority of the tumors are detected incidentally.

• Blood and urine tests
• Radiological studies
  • Ultrasound of abdomen
  • CT and MRI scan of abdomen
• Tissue biopsy of the tumor mass can help achieve a definitive diagnosis
• Molecular testing via next-generation sequencing
• Differential diagnosis includes chordoma, epithelioid malignant peripheral nerve sheath tumor, myoepithelial carcinoma, synovial sarcoma, and small cell carcinoma of the ovary (in girls)

Complications:

• Emotional stress
• Tumor metastasis to different organs and regions
• Incomplete removal results in tumor recurrence

Treatment:

• No staging system is available
• Treatment depends on the location and the size of the tumor
• It may require a combination of surgery, chemotherapy, and radiation therapy
• Individuals with SMARCB1 or SMARCA4 gene abnormalities may be referred to clinical trials and counseling

Prevention: Presently, it is not possible to prevent the formation of Extrarenal Rhabdoid Tumors of the Genitourinary System.

Prognosis:

• Most individuals present with late-stage tumors; since these tumors are highly aggressive, the prognosis is typically poor
• The 5-year survival is between 15-36%