Thyroid Cancer Enters China's Top Three as Diagnoses Rise and Screening Faces Scrutiny

A changing cancer picture across China

China recorded an estimated 5.15 million new cancer cases in 2024, with thyroid cancer among the three most commonly diagnosed cancers and the leading cancer by incidence among both men and women aged 20 to 39. Its rise is changing a national cancer picture once dominated by lung cancer and cancers of the digestive system.

The National Cancer Center's study of age patterns estimated 5,150,600 new cases, including 2,672,000 in men and 2,478,600 in women. It ranked lung cancer first, followed by female breast cancer, thyroid cancer, colorectal cancer and liver cancer. An accompanying question has drawn public attention: how much of the increase comes from finding more small thyroid tumors during examinations?

A national academic analysis, Cancer incidence and mortality, gives a different ordering: lung, thyroid, colorectal, breast and liver cancer. It estimates 2.58 million cancer deaths in 2024 and says those five leading cancers accounted for 59.13% of new diagnoses. The ranking difference is unresolved in the published summaries, although both place thyroid cancer near the top.

The practical message is more precise than a call for everyone to get a thyroid scan. Chinese guidelines recommend screening people at higher risk rather than routinely screening the general population. For someone who already has a thyroid nodule, the next step depends on its appearance, size, location and changes over time.

How researchers estimated the 2024 burden

The National Cancer Center's age analysis used information from 919 cancer registries that met quality requirements. Researchers calculated cancer incidence and mortality by age using 2019 records, separating people by sex and urban or rural residence, and used those results to calibrate estimates for 2024.

The national academic analysis also used 2019 data from 919 registries. For its projections, it drew on 106 registries that had submitted continuous records from 2010 through 2019. Cancer registries collect information about diagnoses and deaths in defined populations, giving researchers a basis for estimating the burden across a much larger country.

The figures describe an estimated burden for 2024, produced using earlier registry records and statistical models. The publication page for the national academic analysis lists June 15, 2026, as its online publication date; 2024 is the year covered by its estimates.

Why the type of rate matters

The age analysis puts China's crude cancer incidence rate at 366.57 cases per 100,000 people in 2024, with a higher rate among men than women. A crude rate describes diagnoses relative to the population as it actually exists, including its particular mix of younger and older people.

The national academic analysis gives an age standardized incidence rate of 207.70 per 100,000 and an age standardized mortality rate of 90.90. Age standardization recalculates rates using a fixed age distribution, in this case the Segi world standard population. It helps researchers compare places and years when their populations have different age structures.

That adjustment matters in China because cancer becomes much more common with age. The same national analysis found that, from 2000 to 2019, the age standardized incidence rate for all cancers rose by an average of 1.6% annually, while the age standardized death rate fell by an average of 1.4% annually. Diagnoses and deaths are moving in different directions after accounting for age.

What three decades of thyroid data show

A separate thyroid cancer trends study, published in Scientific Reports in 2024 by Kaiyuan Huang and colleagues, examined China and the world using the Global Burden of Disease Study 2021. It traced changes from 1990 to 2021 and projected trends through 2036.

The study, Temporal trends of thyroid cancer in China and globally from 1990 to 2021: an analysis of the global burden of Disease Study 2021, was published on October 26, 2024, with DOI 10.1038/s41598-024-77663-5. Its methods and tables describe Joinpoint regression for trends, Das Gupta decomposition to separate the contributions of population aging, population growth and epidemiological changes, and autoregressive integrated moving average, or ARIMA, forecasting.

China's age standardized thyroid cancer incidence rate rose from 1.249 per 100,000 in 1990 to 2.473 in 2021, nearly doubling. Over the same period, the age standardized death rate fell from 0.473 to 0.387 per 100,000, a decline of about 18% calculated from the study's figures.

The estimated average annual rise in China's incidence rate was 2.242%, compared with 1.139% globally. China's average annual decline in thyroid cancer mortality was 0.651%. These estimates come from a different modeling framework and period than the national registry projections.

Table 1 of the Scientific Reports study gives case counts, rates, uncertainty intervals and annual changes. Tables 2 to 4 provide sex-specific incidence, prevalence, mortality and disability-adjusted life years, or DALYs, alongside incidence-to-mortality ratios.

A separate study, Burden of thyroid cancer in China and worldwide from 1990 to 2021: observation, comparison, and forecast from the Global Burden of Disease Study 2021, was published on December 6, 2024, in Frontiers in Endocrinology, with DOI 10.3389/fendo.2024.1500926. It also used Global Burden of Disease 2021 estimates for 1990 to 2021. Its Table 1 provides the following China estimates; rates are age standardized per 100,000 people, and ranges are the study's reported 95% confidence intervals.

The Frontiers in Endocrinology analysis used Joinpoint software 5.2.0 and R 4.4.0, annual and average annual percentage changes, age-period-cohort modeling, DasGupta decomposition and ARIMA forecasting with the forecast package 8.23.0. Its age-period-cohort analysis used consecutive five year intervals from 1992 to 2021, excluding 1990 and 1991. In its decomposition, epidemiological changes mean changes in incidence or death rates after adjusting for age and population size. These two thyroid studies are separate from the national analyses estimating the 2024 burden of all cancers.

For the Scientific Reports projections through 2036, ARIMA uses the historical time series to forecast future rates. Its model selection procedure includes the KPSS test for stationarity, AIC and BIC criteria for comparing models, and the Ljung-Box test for remaining autocorrelation in model residuals. The projections point to continued growth in age standardized incidence and declining age standardized mortality. The Frontiers in Endocrinology study separately forecasts a slow rise in age standardized incidence over the next decade, with death rates declining among women and stabilizing among men.

The main milestones show how the cancer picture has shifted:

• 1990: China's modeled thyroid cancer incidence rate was 1.249 per 100,000 after age standardization.
• About 2003 to 2005: Lung, stomach, liver, esophageal and colorectal cancers occupied the five leading places in China's national cancer ranking.
• 2021: The modeled thyroid cancer incidence rate reached 2.473 per 100,000, while its death rate was lower than in 1990.
• 2024: National estimates placed thyroid cancer among the three most commonly diagnosed cancers.
• 2036: The thyroid study projects an incidence rate of 3.017 and a death rate of 0.344 per 100,000 after age standardization.

Why more scans find more thyroid tumors

The National Cancer Center's age analysis links rising thyroid cancer incidence to the wider use of neck ultrasound and other examinations that can reveal thyroid abnormalities, including CT scans. Examinations performed during health checks or for another medical reason can uncover nodules that a person cannot feel.

The thyroid is a small gland in the neck. A nodule is a lump within it, and a nodule can be benign or malignant. High resolution ultrasound can detect very small lumps, increasing the number of people who receive further assessment.

Figures cited from the Chinese Society of Endocrinology's guideline on thyroid nodules and differentiated thyroid cancer put ultrasound detection of nodules at 20.43% in the general population, or roughly one person in five. The cited proportion of nodules that are malignant is 8% to 16%. Most detected nodules are therefore benign.

The Scientific Reports researchers also identify improved diagnostic technology and greater public health awareness as possible contributors to rising incidence. Their analysis attributes China's increase in thyroid cancer cases to a combination of population aging, population growth and changes in disease patterns, including changes in detection.

In that decomposition, population aging and epidemiological changes were major contributors to rising incidence in China, while population aging was the main contributor to the increase in deaths.

Overdiagnosis is one concern behind the screening debate. It means detecting a cancer that would never have caused symptoms or shortened a person's life. Such a diagnosis can still lead to repeated tests, anxiety and treatment. The studies give no national percentage showing how much of China's thyroid cancer increase comes from overdiagnosis.

Why young adults and older adults both matter

Thyroid cancer ranked first among cancers diagnosed in Chinese men and women aged 20 to 39 in the National Cancer Center's age analysis. For this age group, a thyroid finding can become a major medical issue during years usually associated with education, work and starting a family.

The Global Burden of Disease analysis found that thyroid cancer incidence in 2021 was concentrated mainly between ages 30 and 79, with a peak at 55 to 59. Thyroid cancer can lead the cancer ranking among young adults while its own incidence reaches a higher level later in life. The first comparison is between cancer types within an age group; the second is between ages for one cancer.

Deaths from thyroid cancer in that study were concentrated between ages 50 and 89. The highest number of deaths in China occurred among people aged 75 to 79, putting older patients at the center of efforts to reduce mortality.

Sex also affected the trends. Women accounted for a much larger share of thyroid cancer cases, but men had a less favorable mortality pattern over the full period from 1990 to 2021. The researchers found an increase in men's age standardized mortality across those decades, despite a decline during the most recent decade, and suggested that later diagnosis could be a factor.

A nodule's risk depends on its features

Doctors in China use the C-TIRADS classification system to assess the ultrasound appearance of thyroid nodules. The categories help decide which nodules can be monitored and which may need a needle biopsy, a procedure that collects cells for examination.

Categories 1 to 3 generally indicate benign findings or low concern, with observation commonly advised. Category 4 is divided into 4a, 4b and 4c, representing increasing suspicion of malignancy. Category 5 indicates a high suspicion of cancer.

A category is one part of the assessment. Doctors also consider the nodule's size, position and growth, together with the patient's history. A biopsy or further tissue examination may be needed to establish the diagnosis and guide treatment.

Papillary thyroid cancer accounts for about 80% to 90% of thyroid cancers in the figures cited in the original clinical discussion. It usually grows slowly, and survival at 10 years can exceed 90%. Other types behave differently. Medullary and follicular cancers require their own assessment, while anaplastic thyroid cancer, which accounts for about 1% to 2%, is particularly aggressive and has a five year survival rate usually below 10%.

Those differences make a specific diagnosis essential. Monitoring may be suitable for some carefully selected patients, while others need prompt treatment. Decisions belong in an individual clinical assessment rather than a single rule applied to every thyroid lump.

Why screening recommendations differ by cancer

Chinese guidance recommends thyroid cancer screening for people with higher risk, including those exposed to radiation in the head or neck during childhood and people with a family history of thyroid cancer or relevant genetic mutations. Routine screening of the general population is not recommended.

Screening means testing people before symptoms appear. Its value depends on whether finding disease earlier improves health enough to outweigh the consequences of extra tests and treatment. With thyroid cancer, widespread ultrasound can uncover many benign nodules and some small cancers that grow very slowly.

Lung cancer has a different screening recommendation. China's Lung Cancer Screening and Early Diagnosis and Treatment Plan, 2024 edition, recommends low dose spiral CT for people aged 50 and older who meet high risk criteria. The age threshold is combined with risk assessment rather than applied to every adult.

The National Cancer Center's age analysis also identifies the digestive system as a priority. Incidence of these cancers rises rapidly after age 40, and mortality increases substantially after 50. Its recommendation is to improve screening strategies around the cancers and populations most likely to benefit.

Aging keeps the wider cancer burden high

People aged 60 and older accounted for 61.77% of China's estimated new cancer cases in 2024, according to the age analysis. Incidence was highest among people aged 80 to 84, at 1,476.78 cases per 100,000. Case numbers increased most rapidly after age 40.

National Bureau of Statistics figures cited in the analysis put the population aged 60 and older at 22.0% at the end of 2024, up 3.3 percentage points from the 2020 census. A larger older population increases the need for diagnosis, treatment and continuing care even when death rates adjusted for age improve.

Lung cancer remained the most common cancer among men aged 40 and older and women aged 60 and older. In the national academic analysis, it was also the leading cause of cancer death, followed by liver, colorectal, stomach and esophageal cancers. Together, those five cancers accounted for 66.75% of cancer deaths.

China therefore faces two connected tasks: managing the growing number of thyroid findings without unnecessary treatment, and reducing deaths from cancers that remain especially dangerous. The shift in diagnosis rankings is substantial, while the largest demands on cancer services still come from an aging population and a broad range of diseases.

The thyroid study's projection to 2036 points toward continued growth in incidence alongside a further decline in mortality after age adjustment. For patients, the immediate decisions remain concrete: whether they have risk factors that justify screening, what a detected nodule looks like, and which follow-up or treatment matches its clinical risk.

Key Points

• China had an estimated 5.15 million new cancer cases and 2.58 million cancer deaths in 2024.
• Thyroid cancer ranked among the three most commonly diagnosed cancers and led the cancer ranking for adults aged 20 to 39.
• A study using Global Burden of Disease data found that China's age standardized thyroid cancer incidence nearly doubled between 1990 and 2021, while mortality fell.
• Ultrasound detects thyroid nodules in about one person in five; most nodules are benign.
• Chinese guidance recommends thyroid cancer screening for higher risk groups rather than the general population.
• People aged 60 and older accounted for 61.77% of estimated new cancer cases in 2024, and lung cancer remained the leading cause of cancer death.