title: Staging and monitoring of childhood rhabdomyosarcoma with flow cytometry.
abstract: Patients with metastatic rhabdomyosarcoma (RMS) have a poor prognosis. The detection of contaminating RMS cells in the bone marrow (BM) is important in clinical staging and risk assessment. The cytological examination of the BM remains the gold standard for the diagnosis of RMS, but has a limited sensitivity. In the present study, 32 BM and two cerebrospinal fluid (CSF) samples from 11 patients with suspected metastasis were analyzed by flow cytometry (FCM) with ganglioside D2 (GD2) conjugated with fluorescein isothiocyanate, cluster of differentiation (CD)90-phycoerythrin, CD45-peridinin chlorophyll protein and CD56-allophycocyanin monoclonal antibody cocktail in parallel to morphological examination at diagnosis or during treatment. Five samples (14.7%) were positive for RMS onup morphological examination. By FCM, 16 samples (47.1%) were positive for RMS. A significant difference was identified between the two methods. The four-color FCM assay successfully detected RMS cells in BM samples to a level of 0.01% (1 per 104cells). RMS cells demonstrated a phenotype with CD56+/CD90+/CD45-/GD2-expression, which is different from the CD56+/CD90+/CD45-/GD2+expression phenotype in neuroblastoma cells. The follow-up of four patients by FCM demonstrated that two patients became minimal residual disease-negative following two and four cycles of chemotherapy, respectively, and survived. The other two cases remained FCM-positive despite receiving four courses of chemotherapy and consequently succumbed to progressive disease. In addition, FCM analysis of the CSF samples from one patient confirmed a diagnosis of CSF metastasis with RMS. In conclusion, FCM may have a role not only in staging and monitoring the effects of therapy, but also in providing diagnostic confirmation of CSF metastasis with RMS.
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Hongqiang
authors.initials: H
authors.lastname: Shen
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Yongmin
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Ao
authors.initials: A
authors.lastname: Dong
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Huamei
authors.initials: H
authors.lastname: Li
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Diying
authors.initials: D
authors.lastname: Shen
authors.affiliation: Division of Hematology and Key Laboratory of Reproductive Genetics, Zhejiang University, Ministry of Education, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Shilong
authors.initials: S
authors.lastname: Yang
authors.affiliation: Division of Pathology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Hongfeng
authors.initials: H
authors.lastname: Tang
authors.affiliation: Division of Pathology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Weizhong
authors.initials: W
authors.lastname: Gu
authors.affiliation: Division of Surgery, Children's Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, P.R. China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shu
keywords: bone marrow; flow cytometry; minimal residual disease; prognosis; rhabdomyosarcoma