What is thyroid cancer?
Thyroid cancer occurs when cells grow and divide in an abnormal way in the thyroid, a gland found at the front of the throat under the voice box. There are four main types of thyroid cancer, but the most common types are papillary (70-80% of diagnoses) and follicular (15-20% of diagnoses). The less common types are medullary and anaplastic, which make up 4% and 1% of thyroid cancer diagnoses.
You can access further information about thyroid cancer, including risk factors, symptoms, diagnosis and treatment from Cancer Council Victoria. You can also call our trusted cancer nurses on 13 11 20 for support and to learn about our range of services for people affected by cancer.
The Victorian Cancer Registry also operates an interactive web portal, Data Explorer, which provides more trends and statistics than published here.
How common is thyroid cancer?
In 2021, 785 Victorians were diagnosed with thyroid cancer. Of these, there were 242 males and 543 females, representing 30.8% and 69.2% of the total Victorian thyroid cancer diagnoses, respectively. Currently, thyroid cancer is diagnosed at a rate of 5.1 per 100,000 males and 12.2 per 100,000 females. The median age at diagnosis of thyroid cancer is 55 years in males and 49 in females (Figure 1 & 2). Accounting for 2.1% of all cancers diagnosed and 0.3% of all cancer-related deaths in 2021, thyroid cancer was the 13th most commonly diagnosed cancer and the 30th most common cause of cancer-related deaths in Victoria.
Trends in thyroid cancer over time
Figure 3 shows that since 1982 incidence of thyroid cancer has increased by an average of 6.1% per year in males and increased by an average of 6.5% per year in females. Over the past 39 years, mortality from thyroid cancer has remained stable in males and decreased by 1.8% per year in females.
Thyroid cancer morphology
Figure 4 provides a summary of the different types of cells (morphology) which have caused thyroid cancer among all cases. Most thyroid cancer tumours, 79.8%, present as Papillary carcinoma tumours.
Geographical variance in thyroid cancer by local government area
Figure 5 demonstrates variation in age-standardised incidence rates of thyroid cancer, by local government areas. Darker shading indicates areas with higher rates of thyroid cancer.
Thyroid cancer in people born overseas
Figure 6 shows the age standardised incidence rates of thyroid cancer in Australian-born Victorians compared to other major migrant groups, over the five-year period 2017 to 2021. The highest age standardised incidence rate for thyroid cancer was 8.5 for males born in the Middle East and North Africa region and the lowest rate of 1.9 was observed in males born in the North America region. The highest age standardised incidence rate for thyroid cancer was 21.1 for females born in the Middle East and North Africa region and the lowest rate of 8.1 was observed in females born in the UK and Ireland region.
Thyroid cancer five-year relative survival
Figure 7 shows the change in 5-year survival for thyroid cancer, and the 5-year survival trend for all cancers over the same time period. It demonstrates that five-year relative survival has increased for thyroid cancer between 1986-1990 and 2016-2020 from 82% to 95%.