Sensitive liquid biopsy monitoring correlates with outcome in the prospective international GPOH-DCOG high-risk neuroblastoma RT-qPCR validation study.

Background: Liquid biopsies offer less burdensome sensitive disease monitoring. Bone marrow (BM) metastases, common in various cancers including neuroblastoma, is associated with poor outcomes. In pediatric high-risk neuroblastoma most patients initially respond to treatment, but in the majority the disease recurs with only 40% long-term survivors, stressing the need for more sensitive detection of disseminated disease during therapy.

The reliability of bone marrow cytology as response criterion in metastatic neuroblastoma.

Background: The quantitative assessment of neuroblastoma cell content in bone marrow aspirates for response evaluation has been introduced recently. Data on the concordance of interobserver reports are lacking so far.

Methods: Investigators of seven European countries representing national reference or large oncological centers convened in 2016.

Hypermethylated as Circulating Tumor DNA Marker for Disease Monitoring in Neuroblastoma.

Purpose: Circulating tumor DNA (ctDNA) has been used for disease monitoring in several types of cancer. The aim of our study was to investigate whether ctDNA can be used for response monitoring in neuroblastoma.

Methods: One hundred forty-nine plasma samples from 56 patients were analyzed by quantitative polymerase chain reaction (qPCR) for total cell free DNA (cfDNA; albumin and β-actin) and ctDNA (hypermethylated ).

Lack of immunocytological GD2 expression on neuroblastoma cells in bone marrow at diagnosis, during treatment, and at recurrence.

Background: Loss of disialoganglioside 2 (GD2) expression in neuroblastoma (NB) bone marrow cells has been reported in rare cases. This study investigated prospectively the frequency and the patterns of visible GD2 loss at diagnosis, during treatment, and at recurrence.

Methods: Bone marrow aspirates of patients with new or recurrent stage 4 and 4S NB diagnosed between January 1, 2002 and August 31, 2013 were investigated in parallel by cytology and GD2 immunocytology.

Neuroblastoma messenger RNA is frequently detected in bone marrow at diagnosis of localised neuroblastoma patients.

Introduction: The clinical importance of the detection of neuroblastoma messenger RNA (mRNA) in bone marrow (BM) of localised neuroblastoma patients at diagnosis remains unclear. In this prospective multicentre study, BM samples of a large cohort, were studied using real-time quantitative polymerase chain reaction (qPCR).

Methods: BM samples at diagnosis from 160 patients with localised neuroblastoma were prospectively collected at Dutch and German centres between 2009 and 2013.

Minimal residual disease detection in autologous stem cell grafts from patients with high risk neuroblastoma.

Background: The clinical significance of minimal residual disease (MRD) detected by real-time quantitative PCR (qPCR) in autologous stem cell grafts in high risk neuroblastoma is still controversial. In this retrospective multicenter study, autologous stem cell grafts of a large cohort were studied using a panel of RNA markers.

Procedure: From 104 patients with high risk neuroblastoma, who received autologous stem cell transplantation as first line treatment, 66 peripheral blood stem cells (PBSC) and 38 CD34+ selected grafts were retrospectively collected at 2 Dutch and 12 German centers between 1997 and 2010.

Standardization of the immunocytochemical detection of neuroblastoma cells in bone marrow.

Standard cytomorphological examination of bone marrow (BM) aspirates does not appear to be sensitive enough to detect single neuroblastoma cells. The SIOPEN Neuroblastoma Bone Marrow Committee developed a sensitive and reproducible anti-GD2 immunocytochemical assay and introduced morphological and immunocytological criteria for the interpretation of results. Fixed cytospins were incubated with a commercially available anti-GD2 monoclonal antibody and an APAAP kit.

Lacking immunocytological GD2 expression in neuroblastoma: report of 3 cases.

Immunocytological bone marrow assessment for contamination with neuroblastoma cells is based on their characteristic GD2 surface staining. Neuroblastoma without GD2 expression have been rarely and only after antibody therapy reported. Conventional cytology was performed using Pappenheim staining.