Authors (including presenting author) :
Kan A(1), Leung GKC(1), Wu F(1), Leung YW(1), Lam KY(1), Tong YK(1), Yuen YP(1)
Affiliation :
(1) Department of Pathology, Hong Kong Children’s Hospital
Introduction :
Tumour classification has long been based on histologic findings supported by tissue-based ancillary tests. Molecular biomarkers gain importance in tumour diagnosis, risk stratification and treatment plan in recent decades and even become part of diagnostic criteria for certain entities in recent WHO tumour classifications for CNS tumour and soft tissue tumours which are the commonest tumour types among paediatric solid tumours. Multiple testing in the constrain of limited sample quantity and turnaround time is always a challenge especially in paediatric patients.
Objectives :
To establish in-house workflows for modern tumour diagnosis in a tertiary referral centre for paediatric patients.
Methodology :
Various molecular tests and workflows are developed according to commonly encountered tumour groups in our hospital.
(1) Multiplex ligation-dependent probe amplification (MLPA) for segmental chromosomal aberrations relevant to neuroblastoma (MLPA-NB)
(2) MLPA for genetic variants and copy number changes relevant to glioma (MLPA P370)
(3) Childhood Cancer Panel (DNA Panel)
(4) TruSight RNA Pan-Cancer Panel, Illumina (RNA Panel)
(5) MethylationEPIC, Illumina (Methylation Profiling)
Result & Outcome :
Results:
(1) From August 2020 to end of 2022, a total of 9 MLPA-NB, 6 MLPA-P370, 77 DNA Panel and 44 RNA Panel were performed with positive finding rate of 100%, 50%, 50% and 34% respectively.
(2) Reflex testing workflow streamlines the diagnostic pathway. Hence, sendout tests to local and overseas centres are reduced.
(3) Rebiopsy due to insufficient tissue quantity for testing cases is rare.
Conclusions:
A customized testing workflow composed of various molecular tools has been developed in our hospital. It helps to minimize sendout testing and overcome diagnostic difficulty due to specimen constrain. These molecular tools also provide unprecedented information for precise tumour classification and risk stratification.
