PURPOSE: Tumor relapse is the most frequent cause of @entity204 in stage 4 @entity521 . Since genomic information on the relapse precursor cells could guide targeted therapy, our aim was to find the most appropriate tissue for identifying relapse-seeding clones. EXPERIMENTAL DESIGN: We analyzed 10 geographically and temporally separated samples of a single @entity1 by SNP array and validated the data in 154 stage 4 @entity1 . RESULTS: In the case study, aberrations unique to certain tissues and time points were evident besides concordant aberrations shared by all samples. Diagnostic bone marrow-derived DTCs (disseminated @entity5 cells) as well as the @entity3 and DTCs at relapse displayed a 1q deletion, not detected in any of the seven primary @entity5 samples. In the validation cohort, the frequency of 1q deletion was 17.8%, 10%, and 27.5% in the diagnostic DTCs, diagnostic @entity5 , and DTCs at relapse, respectively. This aberration was significantly associated with 19q and @entity8171 deletions. We observed a significant increased likelihood of an adverse event in the presence of 19q deletion in the diagnostic DTCs. CONCLUSIONS: Different frequencies of 1q and 19q deletions in the primary @entity5 as compared to DTCs, their relatively high frequency at relapse, and their effect on event-free survival (19q deletion) indicate the relevance of analyzing diagnostic DTCs. Our data support the hypothesis of a branched @entity2214 and a parallel progression of primary and @entity3 cells. Therefore, searching for biomarkers to identify the relapse-seeding clone should involve diagnostic DTCs alongside the @entity5 tissue.

Impact of disseminated XXXX cells on the identification of the relapse-seeding clone.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity2214 :: ('MESH:D007945', 'Disease') :: ['clonal evolution'] @entity8171 :: ('546', 'Gene') :: ['ATRX'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'tumors'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastatic tumor'] @entity521 :: ('MESH:D009447', 'Disease') :: ['neuroblastomas'] @entity204 :: ('MESH:D003643', 'Disease') :: ['death']
@entity521 :: (MESH:D009447,Disease) :: ['neuroblastoma']
