Presenting features and treatment outcome of 78 Malaysian children with neuroblastoma.

To study the distribution of presenting features and their prognostic significance in neuroblastoma treated in a single institution in Malaysia. A retrospective study was made of 78 neuroblastoma cases diagnosed and treated in the University Hospital, Kuala Lumpur, Malaysia between June 1982 and February 1997. Diagnosis was established by standard histological criteria. The presenting features were evaluated for their distribution and prognostic influence. Disease-free survival from diagnosis was the outcome variable of interest. The ages ranged from 0.1 to 11 years old (median: 3 years old). The tumor originated from the adrenal glands in 83% and the majority of cases presented in advanced stage (stage III 22%, stage IV 66%). Bone marrow was the commonest site of distant metastasis occurring in 45% of patients. The main presenting signs and symptoms in decreasing order were pallor, fever, abdominal mass, weight loss, and bone/joint pain. Univariate analysis conferred age, initial stage and Hb level as significant prognostic factors. No influence in disease-free survival was found for sex, race, primary site, urinary vanillylmandelic acid level, white cell count and platelet count. Overall 2-year disease-free survival was achieved in 27 (39%) patients. Four patients underwent bone marrow transplant, three of whom achieved 2-year disease-free survival. The results suggest that age, initial stage and hemoglobin level are significant prognostic factors based on univariate analysis. In addition, more Malaysian children presented with adrenal primary site and advanced disease compared to previous reported studies.

The spectrum of beta-thalassemia mutations in Malays in Singapore and Kelantan.

The spectrum of beta-thalassemia mutations in Malays in Singapore and Kelantan (Northeast Malaysia) was studied. Allele specific priming was used to determine the mutations in beta-carriers at -28, Codon 17, IVSI #1, IVSI #5, Codon 41-42 and IVSII #654 along the beta-globin gene. The most common structural hemoglobin variant in Southeast Asia, Hb E, was detected by DNA amplification with restriction enzyme (Mnl1) analysis. Direct genomic sequencing was carried out to detect the beta-mutations uncharacterized by allele-specific priming. The most prevalent beta-mutations in Singaporean Malays were IVSI #5 (45.83%) followed by Hb E (20.83%), codon 15 (12.5%) and IVSI #1 and IVSII #654 at 4.17% each. In contrast, the distribution of the beta-mutations in Kelantan Malays differed, with Hb E as the most common mutation (39.29%) followed by IVSI #5 (17.86%), codon 41-42 (14.29%), codon 19 (10.71%) and codon 17 (3.57%). The beta-mutations in Kelantan Malays follow closely the distribution of beta-mutations in Thais and Malays of Southern Thailand and Malays of West Malaysia. The AAC-->AGC base substitution in codon 19 has been detected only in these populations. The spectrum of beta-mutations in the Singaporean Malays is more similar to those reported in Indonesia with the beta-mutation at codon 15 (TGG-->TAG) present in both populations. The characterization of beta-mutations in Singaporean and Kelantan Malays will facilitate the establishment of effective prenatal diagnosis programs for beta-thalassemia major in this ethnic group.