Análise clínica, laboratorial e evolução de pacientes pediátricos submetidos ao tratamento oncológico: comparação da função cardíaca antes e após o tratamento

Abstract

Introduction:cancer in those under 19 years of age accounts for 1% to 4% of neoplasms. Up to 80% of patients can be cured, provided that the diagnosis is made early and treatment is carried out in specialized centers. There is no consensus on the ideal evaluation for the pediatric population regarding the detection of subclinical alterations, as well as for risk stratification. Objective: to evaluate the clinical and laboratory aspects and the evolution of children and adolescents undergoing oncological treatment at a university institution, in addition to comparing echocardiogram (ECHO) data before and after oncological treatment. Methods: observational study with participants aged zero to 17 years with a cancer diagnosis and undergoing chemotherapy in the last 10 years, until March 2024. After the assent and consent process, the participants underwent clinical and laboratory evaluation (electrocardiogram and ECHO). The calculation of the accumulated anthracycline dose was performed using a dose equivalence table with doxorubicin as a reference. Confirmation of normal distribution of variables was verified by the Shapiro-Wilk test, and chi-square or Fisher tests were used for categorical variables, and parametric or non-parametric tests were used for continuous variables. The Kaplan-Meier curve was applied to analyze survival and according to the accumulated chemotherapy dose. Results: 49 participants with solid and hematologic cancers were included, 25 males, with a body surface area of 1.0 cm2. The median age was 6.8 years [3.2-13.9]. All presented sinus rhythm on the electrocardiogram, with medians of 85 bpm for frequency and 424 ms for the QT interval. The median anthracycline dose was 228 mg/m2 [171.5-375]. Only 5 used dexrazoxane. Mediastinal radiotherapy was performed in three and cancer resection in 10. Left ventricular systolic dysfunction was observed in 22 participants (44.8%), with no influence of sex, age or accumulated anthracycline dose ≥ 250 mg/m2. In the paired echocardiographic analysis before treatment and at the end of follow-up, there was a significant difference in systolic diameter (median of 22 mm versus 25 mm, respectively, p=0.002), diastolic diameter (37 vs 38, p=0.026) and ejection fraction by the Teichholz method (0.68 vs 0.67; p=0.021). Recurrence of the oncological disease was observed in 12 participants during a 19.5-month follow-up, without the influence of systolic dysfunction. Eleven participants died from cancer and/or its complications. Conclusions: there was equivalence between sexes, with a predominance of children in early childhood in this population. There was systolic dysfunction during chemotherapy treatment without influence of sex, age and anthracycline dose. The mortality rate was 22.4%.