Elevated BMI, not a risk factor of thyroid cancer in children with thyroid nodules: JAMA
Boston, Massachusetts: A recent study in the journal JAMA Otolaryngology revealed that in children with thyroid nodules, elevated BMI is not an independent risk factor for thyroid cancer. Further, the stresses the importance of routine thyroid examination in children and adds that any nodules detected should be evaluated based on the risk factors outlines in the current consensus guidelines.
The incidence of thyroid cancer is rising among children and has now become the most common cancer in adolescents. The concurrent increase in childhood obesity and the association between thyroid cancer and obesity in adults led to the hypothesis that obesity may be associated with an increased thyroid cancer risk in children. Initial data supported this hypothesis, Magdalena D. Ivanova, Department of Pediatrics, Boston Children's Hospital, Boston, Massachusetts, and colleagues aimed to verify the association of obesity with thyroid cancer in a large cohort of children with thyroid nodules.
In the cross-sectional study, the researchers analyzed all patients younger than 19 years old who were evaluated for a nonautonomous thyroid nodule (≥1 cm diameter) at Boston Children's Hospital from 1998 through 2020. Using medical records, demographic and clinical data were extracted. The presence of thyroid cancer was assessed histopathologically for resected nodules.
Unresected nodules on the basis of cytologic test results were considered to be malignant or benign on the basis of the cytologic test results and a lack of nodule growth for 1 or more years or indeterminate cytologic test results and a lack of growth for 2 or more years. Body mass index z score' analysis was done as a continuous variable. In the secondary analysis, BMI was analyzed as a categorical variable that compared BMI greater than the 95th percentile vs less than the 95th percentile. Univariable and multivariable logistic regression was performed.
Key findings include:
- A total of 362 eligible pediatric patients (median age, 15.5 years; 291 [80%] girls and 71 [20%] boys) were evaluated for a thyroid nodule. Patients self-identified as Asian (14 [4%]), Black (12 [3%]), Hispanic or Latino (25 [7%]), and White (244 [67%]) (data on 67 [19%] patients were missing).
- · Thyroid cancer was present in 99 of 362 (27%) patients.
- · Thyroid cancer was not associated with BMI z score (odds ratio [OR], 1.14). This association was similar in multivariable analysis.
- · A higher BMI z score was associated with larger nodule diameter (Spearman r = 0.12) and a greater likelihood of undergoing thyroid surgery (OR, 1.32).
- · In the multivariable analysis, the likelihood of undergoing thyroid surgery was independently associated with larger nodule diameter (OR, 1.07) but not with BMI z score (OR, 1.24).
- · In a subanalysis of patients (175 of 362 [48%]) who underwent thyroid surgery, BMI z score remained unassociated with thyroid cancer (OR, 0.93).
- · The results were similar when all analyses were repeated using obesity (BMI greater than 95th percentile) as a categorical variable in place of BMI z score.
To conclude, in the study of pediatric patients evaluated for thyroid nodules, BMI z score was not associated with thyroid cancer.
Reference:
Ivanova MD, Cherella CE, Modi BP, Smith JR, Wassner AJ. Association Between Body Mass Index and Thyroid Cancer in Children With Thyroid Nodules. JAMA Otolaryngol Head Neck Surg. Published online February 17, 2022. doi:10.1001/jamaoto.2021.4455
