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Laboratory Test Directory

Wilms Tumor Loss of Heterozygosity (LOH)


Name Method Department Units
Wilms Tumor Loss of Heterozygosity (LOH) Polymerase chain reaction (PCR)
Capillary electrophoresis
Microsatellite marker analysis
Molecular Genetics

Specimen Requirements

Whole blood

Container Type Container Size Specimen Volume

Purple tube (EDTA)

4 mL 4 mL

Room temperature - 24 hour(s)
Refrigerated - 72 hour(s)

Specimen Preparation

  • Do not centrifuge
  • Do not freeze
  • Keep at room temperature or refrigerate

Paraffin embedded tissue

Container Type Container Size Specimen Volume

Paraffin block


Room temperature - 6 month(s)

Specimen Preparation

  • Protect from heat
  • Keep at room temperature

Snap frozen specimen

Container Type Container Size Specimen Volume

Sterile container


Frozen - 24 hour(s)

Specimen Preparation

  • Freeze immediately after collection.
  • Immediately place on dry ice and transport frozen

Reasons for Rejection

  • Inadequate tissue
  • Tissue degradation
  • Delayed or improper handling
  • Wrong type of specimen
  • Post-treatment tumor specimen


Please click on the Lab Form Link in the Forms Section to print and complete the Pediatric Oncology Test Requisition Form. Submission of completed Test Requisition Form is required, and submission of informed consent form is recommended (but not required).

Children with Wilms tumor have their tumors classified based on stage and histopathology. Many children with Wilms tumor will be enrolled in Children's Oncology Group (COG) protocols. Loss of heterozygosity (LOH) for chromosome regions 1p36 or LOH for 16q22 may be associated with a poorer prognosis in Wilms tumor patients. LOH testing is currently not available through a COG trial and can be ordered clinically through Nationwide Children's Hospital Clinical Genetics Laboratory. A tumor sample AND a normal (germline) sample is required. For tumor sample, please submit snap-frozen, paraffin-embedded, or OCT-embedded tumor tissue. For normal (germline) sample, snap-frozen, paraffin-embedded, or OCT-embedded normal tissue or peripheral blood sample in EDTA tube can be submitted. Samples submitted under a COG protocol can also be used in most cases (some cases may require approval from the study chair); please call the laboratory to confirm sample availability.


1) At least 40% tumor must be present in the submitted tumor sample. A tumor percentage of <40% may be reported as unsatisfactory (no results reported). A pathologist at Nationwide Children's Hospital will perform an internal pathology review on submitted samples to verify tumor percentage.

2) Tumor sample collected during or after the treatment (e.g. post-chemotherapy) CANNOT be accepted. However, pre-treatment relapse tumor samples will be accepted. Ship samples via overnight delivery. Saturday deliveries are accepted. Please check Saturday Delivery on shipment label.

Please call (614) 722-2866 with questions.


Lab Form

CPT Code

  • 81479