1 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Pattern of the Incidence of Thyroid Cancer before and after Universal Salt Iodization in Shanghai Ying ZhengMD, MSc Department of Cancer Control and Prevention Shanghai Municipal Center for Disease Control and Prevention

2 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Thyroid Cancer  Risk factors  Ionizing radiation  History of benign thyroid diseases  Iodine deficiency has been associated with follicular thyroid cancer  its pathogenesis is still unknown Summarized in WHO/IARC --World Cancer Report 2008

3 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Thyroid Cancer Worldwide  141,000 new cases in 2002 worldwide  Rare malignancy  More common in females than in males (M:F sex ratio, 0.36)  2.1% of cancers in women  Stable or slowly increasing in most countries Global Cancer Statistics, 2002

4 肿瘤防治科 Dept. of Cancer Ctr. & Prevention

5 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Debate on Iodized Salt  July 31, 2009 Southern Metropolis Weekly Doubts about Iodized Salt : Over-supplement Causes Diseases?  August 13, 2009 Ministry of Public Health replied: Iodine Intake of Chinese Population is below the upper limit set by WHO

6 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Objectives  Describe the incidence of thyroid cancer in Shanghai;  To study the 30 years time trend in urban area;  Internationally comparison;  Provide evidences for evaluate the health effect of universal salt iodization.

7 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Methods  Data Resources:  Shanghai Cancer Registry  Current pattern:  Incidence by gender, age, district and histological types for the cases diagnosed in  Time trend  Diagnosed in the past 33 years  APC (Annual Percent Change) joinpoint model  Compared with USA  SEER.

8 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Results

9 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Current pattern  Crude incidence rate: 7.18 per  The ASR (W.) : 4.99 per  Ranks 6 th in female, with 3.5 times higher than male

10 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Incidence of Thyroid Cancer in Shanghai in GenderCases Frequency % Crude rate 1/100,000 ASR(W.) 1/100,000 TASR (35-64) 1/100,000 Cum. rate 0-64 % Cum. rate 0-74 % M/I ratio Urban and Rural Male Female Total Urban Male Female Total Rural Male Female Total

11 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Age-specific Incidence of Thyroid Cancer in Shanghai in

12 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Distribution of cases diagnosed by age groups

13 肿瘤防治科 Dept. of Cancer Ctr. & Prevention The histological type of Thyroid cancer  Shanghai  Papillary73.41%  Follicular 3.27%  Medullary 1.47%  World estimated  Papillary 50-80%  Follicular 10-40%  Medullary 5-15%

14 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Pattern of Incidence 2002 ： Comparison Internationally Male Female GLOBOCAN 2002

15 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Change of Age-specific Rate of Thyroid Cancer in Urban of Shanghai from 1973 to 2006 Male Female

16 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Trends of Incidence of Thyroid Cancer among Male in Urban of Shanghai from 1973 to 2006 SegmentPeriodAPCtP Crude rate ASR (W.)

17 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Trends of Incidence of Thyroid Cancer among Female in Urban of Shanghai from 1973 to 2006 SegmentPeriod APCtP Crude rate ASR (W.)

18 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Universal Salt Iodization in China  The Act for the management of salt iodization for avoiding iodine deficiency  State Department Act No.163 P.R.C.  Signed and issued on August 23, 1994 by Premier Li Peng  Enforced began from October 1, 1994

19 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Take 1995 as a cut point Male Seg.PeriodAPCtP Crude rate ASR (W.) Female Seg.PeriodAPCtP Crude rate ASR (W.)

20 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Trends of Incidence of Thyroid Cancer in USA SEER from 1973 to 2006 Male Female

21 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Comparison: Shanghai Vs. US Male Female

22 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Conclusions  Shanghai is among the areas with the highest incidence of thyroid cancer in the world.  Compared to more developed countries.  The incidence of male is at the average level  The incidence of female is above the average level  Continual increase in past 33 years  Similar to US which has compulsory salt iodization for over 80 years  Synchronous with the improvement of Ultrasonic and Biopsy  There is no solid evidence to suggest a relationship between the rise of thyroid cancer incidence and universal salt iodization

23 肿瘤防治科 Dept. of Cancer Ctr. & Prevention Next Steps  Short term ： Case-control Study  Long term ： Risk Factors  Collect and analyze the long-term incidence pattern  Study on interaction on iodin exposure and other environment factors  Genetic factors