METHODS: We retrospectively reviewed the clinical data of pediatric patients (aged <18 years) with CNS tumors diagnosed and treated in the Pediatric Hematology-Oncology Division at the University Malaya Medical Center from 2008 to 2019. We also conducted a web-based survey of the core members of the multidisciplinary team to evaluate the impact of the MDTMs.
RESULTS: During the pre-MDTM era (2008-2012), 29 CNS tumors were diagnosed and treated, and during the MDTM era (2014-2019), 49 CNS tumors were diagnosed and treated. The interval for histologic diagnosis was significantly shorter during the MDTM era (p=0.04), but the interval from diagnosis to chemotherapy or radiotherapy and the 5-year overall survival of the 78 patients did not improve (62.1% ± 9.0% vs. 68.8% ± 9.1%; p=0.184). However, the 5-year overall survival of patients with medulloblastoma or rare tumors significantly improved in the MDTM era (p=0.01). Key factors that contributed to delayed treatment and poor outcomes were postoperative complications, the facility's lack of infrastructure, poor parental education about early treatment, cultural beliefs in alternative medicine, and infection during chemotherapy. Eighteen clinicians responded to the survey; they felt that the MDTMs were beneficial in decision-making and enhanced the continuity of coordinated care.
CONCLUSION: MDTMs significantly reduced the diagnostic interval and improved the overall outcomes. However, delayed treatment remains a major challenge that requires further attention.
METHODS: The pharmacology module consisted of a pharmacokinetic distribution of oseltamivir carboxylate daily area under the concentration-time curve at steady state (simulated for 75 mg and 150 mg twice daily regimens for 5 days) and a pharmacodynamic distribution of viral shedding duration obtained from phase II influenza inoculation data. The epidemiological module comprised a susceptible, exposed, infected, recovered (SEIR) model to which drug effect on the basic reproductive number (R0 ), a measure of transmissibility, was linked by reduction of viral shedding duration. The number of infected patients per population of 100 000 susceptible individuals was simulated for a series of pandemic scenarios, varying oseltamivir dose, R0 (1.9 vs. 2.7), and drug uptake (25%, 50%, and 80%). The number of infected patients for each scenario was entered into the health economics module, a decision analytic model populated with branch probabilities, disease utility, costs of hospitalized patients developing complications, and case-fatality rates. Change in quality-adjusted life years was determined relative to base case.
RESULTS: Oseltamivir 75 mg relative to no treatment reduced the median number of infected patients, increased change in quality-adjusted life years by deaths averted, and was cost-saving under all scenarios; 150 mg relative to 75 mg was not cost effective in low transmissibility scenarios but was cost saving in high transmissibility scenarios.
CONCLUSION: This methodological study demonstrates proof of concept that the disciplines of pharmacology, disease epidemiology and health economics can be linked in a single quantitative framework.