RESUMEN
Purpose: Excess weight in adolescents with cancer during treatment does affect cancer outcomes. Neck circumference (NC), an easygoing anthropometric measure, may present greater metabolic risk, and is associated with excess adiposity. The aim of this study was to identify the prevalence of elevated NC in adolescents with cancer and associated factors. Methods: Cross-sectional study with adolescents aged 10-19 years, under antineoplastic treatment, evaluated from 2015 to 2017, at a Pediatric Oncology Institute's outpatient clinic. Anthropometric parameters were collected, besides diagnosis, sex, and age. The classification of elevated NC was carried out considering cutoff values for adolescents, according to sex and age group. A binary logistic regression was used to determine relationships between NC and associated factors. Results: Among 496 eligible cases, most were male (n = 299, 60.3%). A total of 31.9% of cases had high NC. There is significant and moderate correlation between skinfold thickness (TS) and NC (ρ = 0.6; p = 0.000), and a significant but weak correlation between TS and body mass index (ρ = 0.267; p = 0.000). The adjusted analysis for sex, age group, and type of tumor showed that females are more likely to belong to the high NC category, to have excess adiposity. The age group between 10 and 12 years was the most associated with this outcome (2.795 [0.979-7.977]; p < 0.05). TS is also associated with high NC (1.114 [1.050-1.182]; p < 0.05). Conclusion: It was concluded that there is high prevalence of elevated NC and higher risks for this outcome considering type of tumor, sex, age group, besides being an easy and simple measure for use in clinical practice.