Abstract
OBJECTIVE: To apply the Toronto Childhood Cancer Staging Guidelines (TG) and Estimate the Observed Survival Probabilities for Pediatric Patients with Leukemia and Lymphoma. METHODS: Staging at diagnosis was conducted according to tier 2 of the TG. The study cohort included patients aged 0 -19 years from the Population-Based Cancer Registry (PBCR) of Mato Grosso, diagnosed with leukemia and lymphoma between 2008 and 2017, with follow-up until December 31, 2022. Observed 60-month survivals were calculated using the Kaplan-Meier method. RESULTS: Staging was assigned in 67.3% of cases (n=239), while in 32.7% (n=116), staging could not be applied due to incomplete data. Among the cases of acute lymphoblastic leukemia (ALL), 70.7% (n=133) were staged as CNS1, with an observed survival probability of 75.0%. For acute myeloid leukemia (AML), 42.2% (n=21) were staged as CNS-, with an estimated survival of 60.0%. Most Hodgkin lymphoma (HL) cases were staged as IIA/B (37.7%, n=23) and IIIA/B (21.3%, n=13), with survival probabilities of 91.3% and 91.7%, respectively. Among non-Hodgkin lymphoma (NHL) cases, 32.1% (n=18) were staged as stage III, with a survival probability of 70.6%. CONCLUSION: The application of TG in the PBCR in Mato Grosso proved feasible, allowing for comparability of survival estimates across different stages. However, collecting tier 2 staging information will be a challenge for the PBCR due to incomplete information in medical records.