| Objective To describe the epidemiological characteristics and trends of thyroid cancer incidence in Qidong between 1972 and 2021, and to provide guidelines for prevention and control measures and strategies.
Methods The cancer registry data was collected and analyzed on thyroid cancer incidence during 1972—2021 in Qidong. Crude incidence rate (CR), China age-standardized rate (ASRC), world age-standardized rate (ASRW), The truncated incidence of 35~64 years old, the cumulative incidence rate between the ages of 0 and 74 years old and the cumulative risk were calculated. and average annual change percentage (AAPC) was calculated by Joinpoint software. Age-period-cohort (APC) model used to analyze the influence of age, period and birth cohort on the changes in the incidence trend of thyroid cancer patients.
Results From 1972 to 2021, there were 2 592 patients from thyroid cancer in Qidong, accounting for 1.76% of all cancer new cases, CR of of thyroid cancer was 4.62/105, ASRC was 3.84/105, ASRW was 3.52/105. The truncated incidence of 35~64 years old was 8.53/105, the cumulative incidence rate between the ages of 0 and 74 years old was 0.36%, the cumulative risk was 0.36%. There were 501 patients for male, the CR, ASRC, and the ASRW were 1.81/105, 1.49/105 and 1.38/105. the patients for female were 2 091, and the CR, ASRC, and the ASRW were 7.35/105, 6.12/105 and 5.60/105,respectively. Temporal trends indicated significant upward trends in ASRC among both gender, males and females with AAPC values of 11.84% (P <0.05), 9.12% (P<0.05), and 12.84% (P<0.05), respeclively. The results of the APC model showed that the average net drift value of thyroid cancer incidence in all age groups was 5.39% [95%CI ( 4.25%~6.55% )] , and the highest value of local drit was 8.70% [( 95%CI: 7.54%~9.88%)] in the 30~34 years old group. The incidence of thyroid cancer increased with age. With the passage of time, the risk of thyroid cancer incidence increased gradually: compared with the rate ratio of thyroid cancer incidence（RR=1.00）in 1992—1996，the RR of thyroid cancer incidence increased from 1.76 during 1972—1976 to 28.34 during 2017—2021. The later the cohort was born，the greater the risk of thyroid cancer incidence: compared with the relative risk of thyroid cancer incidence（RR=1.00）in 1952—1956 cohort，the RR of thyroid cancer incidence increased from 0.26 in the 1892—1896 cohort to 5.37 in the 2017—2021 cohort.
Conclusions The incidence of the thyroid cancer has presented a rising trend in the past fifty years, Thyroid cancer incidence increased with age，and the period and cohort effects on the risk of incidence increased. Further research is needed on risk factors related to thyroid cancer. |
