New Search

Laboratory Test Directory

ALK Targeted Sequencing

Components

Name Method Department Units
ALK Targeted Sequencing Polymerase chain reaction (PCR)
Sanger sequencing
Targeted sequence analysis
Molecular Genetics

Specimen Requirements

Whole blood

Container Type Container Size Specimen Volume
Required

Purple tube (EDTA)

4 mL 4 mL
Stability

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

Specimen Preparation

  • Do not centrifuge
  • Do not freeze
  • Transport to laboratory as soon as possible

Snap frozen specimen

Container Type Container Size Specimen Volume
Required

Sterile container

N/A
Stability

Frozen - 24 hour(s)

Specimen Preparation

  • Freeze immediately after collection.
  • Immediately place on dry ice and transport frozen
  • Transport to laboratory as soon as possible

Reasons for Rejection

  • Inadequate tissue
  • Tissue degradation
  • Delayed or improper handling

Comments

Please click on the Lab Form Link in the Forms Section to print and complete the Genetic Test Requisition Form. Submission of completed Genetic Test Requisition Form is required, and submission of informed consent form is recommended.

Targeted sequencing of exons 21-28 of the ALK gene can be ordered either as a somatic testing done on neuroblastoma (NBL) sample or as a germline (constitutional) testing done on blood sample. Primarily, targeted ALK sequencing is offered in the context of pediatric NBL and done on the tumor sample. Children with NBL are assigned a specific risk group (low, intermediate, or high) based on a variety of clinical and biological factors.

Most children with NBL will be enrolled in Children?s Oncology Group (COG) protocols. However, our laboratory offers the targeted ALK sequencing and ALK amplification detection by FISH on a clinical basis for those patients who are NOT enrolled in a COG protocol or need testing to be done off-study. Samples submitted under a COG protocol can be used in most cases (some cases may require approval from the study chair); please call the laboratory to confirm sample availability.

The detection rate of somatic ALK mutations in NBL is estimated to be 15-20%. For mutations reported as likely pathogenic or variant of unknown significance, a germline sample (e.g. blood sample) from the patient is required to determine whether the variant is present only in the tumor (somatic) or is present in all cells (germline).

Please note, at least 40% tumor must be present in the submitted sample (based on internal pathology review) for accurate reporting of somatic mutations. Germline (constitutional) ALK sequencing of exons 21-28 can also be performed in suspected cases of hereditary NBL.

While hereditary NBL is rare (~1-2% of NBL cases), approximately 50% of familial forms are due to germline ALK mutations in the kinase domain. Blood sample can be submitted for germline testing.

Please call (614) 722-2866 prior to shipping and provide tracking number. Ship for overnight delivery. Saturday are deliveries accepted. Please check Saturday Delivery on shipment label.

Forms

Lab Form

CPT Code

  • 81479