Acute lymphoid and myeloid leukemia in a Brazilian Amazon population: Epidemiology and predictors of comorbidity and deaths

Abstract

Introduction Leukemia is the most common cancer in children and has the highest rates of incidence in industrialized countries, followed by developing countries. This epidemiologic profile can mainly be attributed to the availability of diagnostic resources. In Brazil, leukemia diagnosis is a challenge due to financial viability, lack of hemovigilance services in isolated regions and the vast size of the territory. Its incidence in the state of Amazonas has been increasing since 2010. Therefore, this study aims to describe the epidemiological pattern and spatial distribution of patients with acute lymphoid leukemia and acute myeloid leukemia in Amazonas and identify the predictors of comorbidity and death. Materials and methods A retrospective cross-sectional study was carried out based on patients’ data which was obtained from the database of a referral center for the period of 2005 to 2015. Variables included age, gender, ethnicity, civil status, schooling, income, location of residence, subtype of leukemia, comorbidities, and date of death. The spatial distribution was performed using QGIS v.2.18. Stata software was used for univariable and multivariable logistic regression to evaluate the association between both comorbidities and death for all characteristic groups of ALL and AML. Results The group that was studied was composed of 577 ALL and 266 AML patients. For both, most patients were male, with a schooling period of 1–4 years, received<1 minimum wage, and lived mostly in Manaus, followed by the municipality of Tefé. There was no association between the development of comorbidities and analyzed variables in patients with ALL. AML patients that were >60 years old and with family history of the disease had the highest risk of developing comorbidities (OR = 5.06, p = 0.038; OR = 2.44, p = 0.041, respectively). Furthermore, patients with ALL and in the 41-50-year age group had a higher risk of death (OR = 31.12; p = 0.001). No association between death and explanatory variables were found in patients with AML. In addition, significant difference was observed in time to death (chi2 = 4,098.32, p = 0.000), with 50% of patients with AML dying within two years after diagnosis, whereas in ALL, this percentual of death only is reached in approximately 5 years. Conclusion Our study describes the data of patients with acute leukemia in Amazonas, a remote region in the north of Brazil. In addition, it highlights the importance of hemovigilance in an Amazon region state, while focusing on peripheral areas which don't have prevention, diagnosis and treatment tools for this disease.

Influence of Dose Intensity in Consolidation with HIDAC and Other Clinical and Biological Parameters in the Survival of AML

“…This result is lower than what is reported in studies in countries such as the United States and the United Kingdom where figures of 70% are reached ("Acute myeloid leukemia (AML) statistics |Cancer Research UK"; Howlader et al, . In Colombia and Latin America, the age distribution is heterogenous; in some studies, the median age and the patients over 60 years are similar to our study [14,18,22], but in other reports, the patients described are younger than expected, where the median age was around 40 years [11,12,[15][16][17]23], which could be associated with the design of the studies and particularities in the Latin America population in the presentation of the disease and that the majority of the studies are not demographic-based.…”

“…Within the hematological and cytogenetic parameters, 8.2% of the patients presented hyperleukocytosis with leukocyte counts greater than 100,000 cells/mm3 and abnormal karyotype in 25 patients (29.0%). Considering the genetic abnormality identified in the tumor cells in the bone marrow sample at the time of diagnosis, 7% of the patients were grouped at favorable risk, 50.0% at intermediate risk, 22.1% in adverse risk, and 20.9% could not be classified. According to the morphological (myelogram) and immunophenotypic criteria by multiparameter flow cytometry, the most frequent AML was acute monoblastic leukemia (24.4%), followed by AML with and without maturation (15.1%).…”

Leukemia mortality in children from Latin America: Trends and predictions to 2030

“…Age-standardized mortality rates (ASMRs) were calculated based on information on the adjusted number of deaths, using the direct method and the world standard SEGI population per 100,000 persons-years (20). Leukemia mortality trends were analyzed for the age group of 0 to 14 years (0-4, 5-9, and [10][11][12][13][14] between 2000 and 2017. We also provided an estimate of overall leukemia mortality rates in the LAC for the year 2030.…”

“…For example, Mexico reported a rise of mortality rates (19.19% in boys and 20.98% in girls) between 1980 and 2014 (9). The barriers to healthcare access, social disparities, and the lack of economic resources in this region hamper the survival improvements seen in high-income countries (10,11). Other factors related to increased mortality include delayed diagnosis, treatment abandonment, lack of a proper supportive care, lack o national pediatric cancer registries, and a shortage of pediatric oncologists as well as nurses dedicated to pediatric oncology care (12,13).…”

Leukemia mortality in children from Latin America: trends and predictions to 2030

“…For example, between 1980 and 2014, Mexico reported a rise of mortality rates of leukemia (19% in boys and 21% in girls) [ 10 ]. The barriers to healthcare access, social disparities, and the lack of economic resources in LAC hamper the survival improvements seen in high-income countries [ 11 , 12 ]. Other factors related to increased mortality include delayed diagnosis, treatment abandonment, lack of a proper supportive care, and a shortage of pediatric oncologists as well as nurses dedicated to pediatric oncology care [ 13 , 14 ].…”