Staging at Diagnosis and Survival of Hematologic Neoplasms in Children and Adolescents in Mato Grosso, Brazil: A Population-based Study.

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.