Anthropometric Factors and Thyroid Cancer Risk by Histological Subtype: Pooled Analysis of 22 Prospective Studies

Abstract

Background: Greater height and body mass index (BMI) have been associated with an increased risk of thyroid cancer, particularly papillary carcinoma, the most common and least aggressive subtype. Few studies have evaluated these associations in relation to other, more aggressive histologic types or thyroid cancer-specific mortality. Methods: This large pooled analysis of 22 prospective studies (833,176 men and 1,260,871 women) investigated thyroid cancer incidence associated with greater height, BMI at baseline and young adulthood, and adulthood BMI gain (difference between young-adult and baseline BMI), overall and separately by sex and histological subtype using multivariable Cox proportional hazards regression models. Associations with thyroid cancer mortality were investigated in a subset of cohorts (578,922 men and 774,373 women) that contributed cause of death information. Results: During follow-up, 2996 incident thyroid cancers and 104 thyroid cancer deaths were identified. All anthropometric factors were positively associated with thyroid cancer incidence: hazard ratios (HR) [confidence intervals ( . Associations for baseline BMI and waist circumference were attenuated after mutual adjustment. Baseline BMI was more strongly associated with risk in men compared with women ( p = 0.04). Positive associations were observed for papillary, follicular, and anaplastic, but not medullary, thyroid carcinomas. Similar, but stronger, associations were observed for thyroid cancer mortality. Conclusion:The results suggest that greater height and excess adiposity throughout adulthood are associated with higher incidence of most major types of thyroid cancer, including the least common but most aggressive form, anaplastic carcinoma, and higher thyroid cancer mortality. Potential underlying biological mechanisms should be explored in future studies.

Avoidable cancer cases in the Nordic countries – The impact of overweight and obesity

“…(10, 42) For thyroid cancer, multiple myeloma and gastric cardia cancer we used RRs from the meta analyses referred to in the report from the IARC working group, assuming that the RR for obese is the RR for overweight squared when categorical exposure was used. (2,(43)(44)(45) The RRs used in our estimations are presented in Table 1.…”

The utility of thyroid ultrasonography in the management of thyroid nodules

“…14,17,25,27,28 The proper application of this system would benefit most from the use of standardized synoptic reporting tools that have been embraced by the surgical community as well as pathologists. In varied settings, including thyroid cancer and pancreatic cancer, synoptic reporting has been examined by international studies and validated as a method for capturing clinical data and improving patient outcomes.…”

“…While individual assessments of sensitivity and specificity could vary, our results are qualitatively similar to those documented in studies that examined individual ultrasound features and the likelihood of malignancy in both urban and rural settings. 14,17,25,27,28 We acknowledge that there may be differences in the capabilities of individual ultrasonography machines that may limit in some form the reports provided. Finally, this was a retrospective assessment, and over the timeframe of the study there have been upgrades in technology and changes in ultrasonography protocol in different institutions.…”

Prospective Study of Ultraviolet Radiation Exposure and Thyroid Cancer Risk in the United States

“…However, the steep rise in the incidence of large and advanced stage papillary thyroid cancer and an increase in thyroid cancer mortality have led some investigators to hypothesize that environmental factors have also contributed to the changing incidence of thyroid cancer (4–6). Apart from ionizing radiation exposure in childhood(7–9), obesity(10), and non-malignant thyroid disease (11, 12), few potentially modifiable risk factors have been identified.…”