ABSTRACT: The clinical hallmark of neuroblastoma is heterogeneity. Biologically, ploidy and N-Myc amplification are currently the only 2 features used to define risk group and to determine therapy. Tyrosine kinase neurotrophin receptors (Trks, including TrkA, TrkB, and TrkC) are important in the clinical and biological behavior of neuroblastomas. The authors aim to study Trks gene expression in their local population of advanced neuroblastoma patients. Multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) assay on the expression of TrkA, TrkB, TrkB-truncated, and TrkC was performed on a total of 19 advanced neuroblastoma archival tumors, diagnosed in KK Women's and Children's Hospital between 2003 and 2007. Of the 19 tumors investigated, Trks expression was present in 14 (73.6%) cases. Of these cases, 8 (42.1%), 10 (52.6%), 7 (36.8%), and 6 (31.6%) expressed TrkA, TrkB, TrkB-truncated, and TrkC receptor mRNAs, respectively. Subsequently, the authors compared Trks expression with N-Myc amplification status of the 19 patients. N-Myc was amplified in 5 (26.3%) of the cases. Within the non-N-Myc-amplified group, Trks expression was present in 9 (64%) of the 14 cases. The significant expression of Trk isoforms among advanced neuroblastoma cases as evident from this study support their role as possible risk assessment tools alongside N-Myc amplification status.
Pediatric Hematology and Oncology 07/2011; 28(7):571-8. · 0.89 Impact Factor
ABSTRACT: To investigate social, clinical, and disease-related factors associated with diagnostic delay.
Two-hundred and 9 solid tumor cases reported to the Singapore Childhood Cancer Registry at KK Hospital between 1997 and 2007 were reviewed retrospectively. The natural logarithms of total delay times were correlated with social, clinical, and disease factors using univariate and multivariate analysis. Subanalysis was performed for the periods before and after first healthcare contact, which were defined as parental and physician delay, respectively.
Mean total delay was 11.6 weeks. Mean parental and physician delay was 7.7 and 4.0 weeks, respectively. Shorter delay was associated with younger age (P<0.05), incidental detection by healthcare workers (P<0.001), and first presentations to pediatricians and nonpediatric emergency departments (P=0.01). Tumor type (P<0.01) and site (P=0.001) were also significantly related. After adjustment for other factors, extracranial germ cell tumors, abdominal tumors and first presentation to nonpediatric emergency departments were significantly associated with shorter total delay. Disease stage remained constant over time, with 30% presenting in stage 4.
Patient age, first healthcare contact, tumor type, and site were significantly related to diagnostic delay in pediatric solid tumors. Our findings reflect factors related to delay in an urban island-state with minimized confounding by healthcare access and geographic factors.
Journal of Pediatric Hematology/Oncology 10/2009; 31(10):734-8. · 1.16 Impact Factor
ABSTRACT: Medulloblastoma/primitive neuroectodermal tumour is the most common type of malignant brain tumour in children. Long-term survival rates have improved over the years with a combination of surgical, radiotherapeutic and chemotherapeutic treatment modalities in the developed world. This paper aims to analyse the epidemiology and outcome of medulloblastoma in Singapore and compare our results with those reported in the literature.
A 9-year retrospective study was done using data reported to the Singapore Children's Cancer Registry from June 1997 to June 2005. Only 39 children up to the age of 15 years diagnosed histologically with medulloblastoma or primitive neuroectodermal tumour arising from the cerebellum were included in the study. Follow-up data were collected up to June 2006 and analysed using SPSS v 13.0 software.
Medulloblastoma/primitive neuroectodermal tumour was the most common type of brain tumour, accounting for 40.7% of all brain tumours diagnosed in children in Singapore. The 5-year event-free survival rate was 44.5%, while the 5- year overall survival rate was 51.5%. Nearly half (41%) of our patients had spinal metastasis at presentation and this was associated with a worse event-free survival (6.3% vs 71.9%, P = 0). Children under 36 months of age had a significantly poorer overall survival (28.8% vs 52.2%, P = 0.041).
The outcome of medulloblastoma in Singapore was inferior to reported figures in the literature. We need to close identified gaps in care, like standardising assessment and treatment protocols, in order to improve our results. Research into molecular and genetic characteristics may also throw light on whether the disease is inherently more aggressive in our population.
Annals of the Academy of Medicine, Singapore 06/2007; 36(5):314-8. · 1.25 Impact Factor