Studying Chromosomes in Samples From Younger Patients With Neuroblastoma

• Event-free survival (EFS) calculated from the date of diagnosis to the date of disease progression, death from any cause, or secondary neoplasm estimated by the Kaplan-Meier method [ Designated as safety issue: No ]
• Incidence of metastatic relapses using cumulative incidences [ Designated as safety issue: No ]
• Difference in patients with and without segmental aberrations using the log rank-test and Grey's test and the model of Fine and Grey for the evaluation of statistical significance [ Designated as safety issue: No ]
• Interactions between age and segmental aberrations using Cox' regression model [ Designated as safety issue: No ]

RATIONALE: Studying samples of tumor tissue from patients with cancer in the laboratory may help doctors learn more about changes that occur in DNA and identify biomarkers related to cancer.

PURPOSE: This research studies chromosomes in samples from younger patients with neuroblastoma.

OBJECTIVES:

• Determine the impact on overall survival of patients with non-MYCN neuroblastoma below 18 months of age as compared to neuroblastoma patients above 18 months of age.

OUTLINE: Archived DNA samples are analyzed for segmental chromosome aberrations by multiplex ligation-dependent probe amplification (MLPA), a polymerase chain reaction (PCR)-based technique. The following genomic regions are being studied: 1p, 1q, 3p, 4p, 7q, 9p, 11q, and 17q, as are the copy numbers of MYCN, NAG, DDX1, and ALK genes.

• Genetic: DNA analysis
• Genetic: nucleic acid amplification
• Genetic: polymerase chain reaction
• Other: laboratory biomarker analysis

DISEASE CHARACTERISTICS:

• Samples from neuroblastoma patients who, according to risk stratification, did not receive cytotoxic treatment and did never receive chemotherapy and are in complete response (CR) OR patients who, according to risk stratification, did not receive cytotoxic treatment initially, but had a localized or a systemic (stage Ms or M) relapse with or without following chemotherapy

  • Low-risk Children Oncology Group (COG) designation: no initial cytotoxic treatment, any stage, any age, any outcome
• DNA from untreated neuroblastoma tumor samples (from patients in the age group below and from patients in the age group above 1.5 years of age) available from the COG, Europe, Israel, and Japan
• No MYCN amplification
• No Schwann cell stroma-rich tumors
• No tumor cell content below 60%
• No DOT

PATIENT CHARACTERISTICS:

• No patients diagnosed before 1997 and after 2005
• No lack of follow-up data

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No initial cytotoxic treatment