The spectrum of cancers commonly found in adolescents and young adults (AYAs) differs from those in children and adults; therefore, the childhood classification is not appropriate for this population. Here we used a newly proposed classification system to reclassify cases of AYAs from Brazilian population-based cancer registries (PBCRs) in 5 geographic regions of Brazil. We aimed to describe the cancer incidence rates within this age group according to PBCR. Using the world population, incidence rates per million were analyzed in each diagnostic subgroup according to sex and age at diagnosis (15 to 19 y, 20 to 24 y, and 25 to 29 y). The median incidence rate was 232.31 per million for females and 218.07 per million for males. Incidence increased with age, with the highest rate observed for 25- to 29-year-olds in both sexes. Carcinomas, lymphomas, and skin tumors were most frequent among AYAs. High incidence rates of cervix-uterus carcinoma were observed in most PBCRs. AYAs present epidemiological characteristics that differ from those of children, reinforcing the need for a new classification. This study describes, for the first time, the cancer incidence rate in AYAs in Brazil, and we believe that our findings represent the Brazilian profile.

Mortality in Brazilian AYA was slightly higher than in other studies conducted throughout the world. When separated by tumor type, Brazil presents a specific pattern, with high mortality from cervical cancer.

OBJECTIVES: Bone cancers occur frequently in children, adolescents, and young adults aging 15 to 29 years. Osteosarcoma and Ewing sarcoma are the most frequent subtypes in this population. The aim of this study was to describe incidence and mortality trends of bone cancers among Brazilian children, adolescents and young adults. METHODS: Incidence information was obtained from 23 population-based cancer registries. Mortality data were extracted from the Atlas of Cancer Mortality from 1979 to 2013. Specific and adjusted rates per million were analyzed according to gender, morphology and age at diagnosis. Median rates were used as a measure of central tendency. Joinpoint regression was applied to analyze trends. RESULTS: Median incidence rates were 5.74 and 11.25 cases per million in children and young adults respectively. Osteosarcoma in the 15-19 years aged group had the highest incidence rates. Stable incidence rates were observed among five registries in 0-14 year's age group. Four registries had a decreased incidence trend among adolescents and young adults. Median mortality rates were 1.22 and 5.07 deaths per million in children and young adults respectively. Increased mortality was observed on the North and Northeast regions. Decreased mortality trends were seen in the South (children) and Southeast (adolescents and young adults). CONCLUSION: Osteosarcoma and Ewing Sarcoma are the most incident bone cancers in all Brazilian regions. Bone cancers showed incidence and mortality patterns variation within the geographic regions and across age groups, although not significant. Despite limitations, it is crucial to monitor cancer epidemiology trends across geographic Brazilian regions.

Background Rare childhood cancer is challenging to define. The Italian Pediatric Rare Tumor (TREP) Study considers rare tumors to include solid malignancies characterized by an annual incidence rate of <2 cases per 1 million and not enrolled in clinical trials. The objective of the current study was to analyze the population incidence rate of rare tumors among children and adolescents (those aged birth‐19 years) in Brazil. Methods Incidence data were obtained from 19 population‐based cancer registries covering the 5 geographic regions in Brazil. Newly diagnosed cases were selected according to the TREP definition, using the International Classification of Diseases for Oncology. To calculate the crude incidence rate, the numbers of incident children and adolescents with a specific rare cancer were divided by the corresponding person‐years lived for the population aged <20 years during the same period. Results Two tumors had an incidence rate that was >2 cases per 1 million (thyroid and skin cancers) in adolescents only. Several tumors demonstrated variations in incidence across the Brazilian regions. Adrenocortical carcinoma had a high incidence rate (4 cases per 1 million) in the south region among children aged <10 years. Thyroid and skin carcinoma had higher incidence rates in the midwest, southeast, and south regions. Conclusions Due to the extraordinary rarity of these events, networking is important for improving basic research, clinical studies, and trials. Centralization of diagnosis is the only way to improve the diagnosis and treatment of children affected by these rare diseases. The registration and surveillance of rare pediatric cancers are crucial from a public health point of view, and therefore the quality of registration has to be improved.

An elevated risk of treatment on medical oncology wards was observed for older patients and those treated in the South. Bone tumors were generally treated in pediatric oncology wards, while skin cancers were treated in medical oncology wards, regardless of age, gender, and region.