Collect whole blood in a purple top (EDTA) tube (preferred). Extracted DNA is also acceptable.
Unacceptable Conditions
Heparinized specimens, severely hemolyzed specimens, frozen, clotted or possibly commingled specimens, blood in non-sterile or leaky containers, mislabeled or inappropriately labeled specimens.
Storage/Transport Temperature
For CHOP Phlebotomy: Samples can be collected throughout the week. Samples collected on weekends or holidays are held in Central Labs and sent to the Genomic Diagnostic Lab the following business day.
For External Clients: Refrigerate sample until shipment. Send the sample at room temperature with overnight delivery for receipt Monday through Friday, optimally within 24 hours of collection.
Please contact the lab (267-426-1447) with questions regarding non-blood specimens.
Volume Required
5 ml whole blood or 1 ug DNA
Minimum Required
3 ml whole blood
Phlebotomy Draw
Yes
Clinical Features
Neuroblastoma is a cancer of early childhood that arises from the developing autonomic nervous system and accounts for 15% of childhood cancer mortality. Neuroblastoma usually occurs sporadically but a subset of neuroblastoma cases are inherited in an autosomal dominant manner. Heritable mutations in the anaplastic lymphoma kinase (ALK) oncogene have been shown to be the main cause of familial neuroblastoma. A small subset of patients with presumed genetic predisposition to neuroblastoma also have germline mutations in the PHOX2B gene.
Performing Lab
Division of Genomic Diagnostics
Performed
Mon - Fri 9:00am to 4:00pm
Reported
28 days
Detection Rate
Although data regarding the frequency of mutations is limited, missense mutations have been identified in up to 3% of patients with germline mutations and from 6-12% in patients with a somatic mutation in the tumor. These mutations have been identified mostly in the tyrosine kinase domain of the ALK gene. The detection rate is higher in families with high risk for predisposition to neuroblastoma (High risk is 3 or more affected individuals of close relation). Research studies to determine the frequency of mutations in the ALK gene are ongoing. The frequency with which PHOX2B germline mutations are identified in patients with presumed genetic disposition to neuroblastoma (familial reoccurrence, and/or associated disorder and/or multifocal primary tumors) is ~6 -11 %.
Utility
The clinical utility of the assay is in assessing the risk to other first degree relatives by genotyping at risk family members for already identified mutations, and establishing the need for continued clinical surveillance of the patient for the purpose of early detection of tumors.
Synonyms
Neuroblastoma (PHOX2B Gene Sequence Analysis)
PHOXS
LIS Mnemonic
PHOXS
Available STAT
No
Test Notes
We offer DNA sequence analysis of the entire coding region of the PHOX2B gene. PCR amplification and sequencing is performed on all coding exons including splice junctions. The patient's gene sequence is then compared to a reference sequence. Sequence variants are classified as mutations, variants of unknown significance or benign variants unrelated to disease. Variants of unknown significance may warrant further studies in the patient and other family members. Large deletions, mutations in promoters, deep intronic regions and other regulatory regions will not be identified with this assay.
Molecular Testing Notes
PHOX2B maps to chromosome 4p12 and encodes a highly conserved homeobox domain transcription factor. PHOX2B mutations have been identified in familial as well as sporadic cases of neuroblastoma. Mutations in the PHOX2B gene also cause congenital central hypoventilation syndrome (CCHS).
CPT Codes
81404
Collection
Collect
Collect whole blood in a purple top (EDTA) tube (preferred). Extracted DNA is also acceptable.
Unacceptable Conditions
Heparinized specimens, severely hemolyzed specimens, frozen, clotted or possibly commingled specimens, blood in non-sterile or leaky containers, mislabeled or inappropriately labeled specimens.
Storage/Transport Temperature
For CHOP Phlebotomy: Samples can be collected throughout the week. Samples collected on weekends or holidays are held in Central Labs and sent to the Genomic Diagnostic Lab the following business day.
For External Clients: Refrigerate sample until shipment. Send the sample at room temperature with overnight delivery for receipt Monday through Friday, optimally within 24 hours of collection.
Please contact the lab (267-426-1447) with questions regarding non-blood specimens.
Volume Required
5 ml whole blood or 1 ug DNA
Minimum Required
3 ml whole blood
Phlebotomy Draw
Yes
Ordering
Clinical Features
Neuroblastoma is a cancer of early childhood that arises from the developing autonomic nervous system and accounts for 15% of childhood cancer mortality. Neuroblastoma usually occurs sporadically but a subset of neuroblastoma cases are inherited in an autosomal dominant manner. Heritable mutations in the anaplastic lymphoma kinase (ALK) oncogene have been shown to be the main cause of familial neuroblastoma. A small subset of patients with presumed genetic predisposition to neuroblastoma also have germline mutations in the PHOX2B gene.
Performing Lab
Division of Genomic Diagnostics
Performed
Mon - Fri 9:00am to 4:00pm
Reported
28 days
Detection Rate
Although data regarding the frequency of mutations is limited, missense mutations have been identified in up to 3% of patients with germline mutations and from 6-12% in patients with a somatic mutation in the tumor. These mutations have been identified mostly in the tyrosine kinase domain of the ALK gene. The detection rate is higher in families with high risk for predisposition to neuroblastoma (High risk is 3 or more affected individuals of close relation). Research studies to determine the frequency of mutations in the ALK gene are ongoing. The frequency with which PHOX2B germline mutations are identified in patients with presumed genetic disposition to neuroblastoma (familial reoccurrence, and/or associated disorder and/or multifocal primary tumors) is ~6 -11 %.
Utility
The clinical utility of the assay is in assessing the risk to other first degree relatives by genotyping at risk family members for already identified mutations, and establishing the need for continued clinical surveillance of the patient for the purpose of early detection of tumors.
Synonyms
Neuroblastoma (PHOX2B Gene Sequence Analysis)
PHOXS
LIS Mnemonic
PHOXS
Available STAT
No
Test Notes
We offer DNA sequence analysis of the entire coding region of the PHOX2B gene. PCR amplification and sequencing is performed on all coding exons including splice junctions. The patient's gene sequence is then compared to a reference sequence. Sequence variants are classified as mutations, variants of unknown significance or benign variants unrelated to disease. Variants of unknown significance may warrant further studies in the patient and other family members. Large deletions, mutations in promoters, deep intronic regions and other regulatory regions will not be identified with this assay.
Molecular Testing Notes
PHOX2B maps to chromosome 4p12 and encodes a highly conserved homeobox domain transcription factor. PHOX2B mutations have been identified in familial as well as sporadic cases of neuroblastoma. Mutations in the PHOX2B gene also cause congenital central hypoventilation syndrome (CCHS).
