英國癌研所的多方麵觀點:

認為:

The reason for this increase is unclear, although a study in the United States - which has also seen an increasing trend of thyroid cancer incidence rates - concluded that increasing incidence trends reflect better detection of subclinical disease rather than a true increase in incidence.7 A study in South East England also suggested this may be the case with widespread use of ultrasound detecting incidental nodules.8 However, other studies have suggested that improved and increased diagnostic activity can not completely explain the increase in rates.9,10 Changes in the patterns of risk factors such as use of medical diagnostic radiation, obesity rates and the iodine fortification of salt might have contributed to the increase in rates, but other unknown risk factors could also have had an impact.11-13