In 2021, cancer accounted for 14.57% (95% UI, 13.65–15.28) of total mortality and 8.8% (7.99–9.67) of total DALYs across both sexes globally. During the same period, the ASIR and ASDR were 790.33 (694.43–893.01) and 116.49 (107.28–124.69), respectively (Table 1). Figure 1 depicts the disparities in the incidence rates and proportion of cancer cases between males and females. In 2021, females exhibited a higher ASIR than males (923.44 versus 673.09), while males exhibited a higher ASDR than females (145.69 versus 93.60). In both sexes, non-melanoma skin cancer exhibited the highest ASIR (74.10), followed by tracheal, bronchial, and lung (TBL) cancer (26.43), colon and rectal cancer (25.61), breast cancer (24.56), prostate cancer (15.37), and stomach cancer (14.33). TBL cancer exhibited the highest ASDR (23.50), followed by colon and rectal cancer (12.40), stomach cancer (11.20), breast cancer (7.90), and esophageal cancer (6.25). In females, breast cancer exhibited the highest ASIR (46.40) and ASDR (14.55). In males, TBL cancer exhibited the highest ASIR (37.85) and ASDR (34.32). Digestive cancer accounted for 39.29% of all cancer-related deaths (Figure S1).

Differences in incidence rate and proportion of cancer cases among males and females

Age-related sex-specific patterns exhibited some variation. Between 1990 and 2021, females exhibited a higher cancer incidence and ASIR than males, and ASIR demonstrated a stable trend. Between 1980 and 2021, males exhibited a higher rate of cancer deaths and ASDR than females, and ASDR demonstrated a decreased trend. The ASDR of cancer decreased by approximately 24.81% in males and 24.47% in females in the past 40 years globally (Fig. 2). In 2021, breast cancer accounted for 5.28% of all cancer incidence and 15.29% of cancer-related deaths in females. Prostate cancer accounted for 4.89% of all cancer incidence and 7.72% of cancer-related deaths in males. The ASIR of breast cancer in females was 46.40 (43.26–49.56), and the ASDR was 14.54 (13.45–15.56). The ASIR of prostate cancer in males was 34.05 (31.27–36.00), and the ASDR was 12.63 (11.16–13.55). From 1990 to 2021, the percentage change in ASIR was 0.04% (0.01–0.07), while the percentage change in ASIR was –0.02% (–0.04, 0) from 2019 to 2021. The percentage change in ASDR decreased from 1990 to 2021 and from 2019 to 2021 (Table S1). In 2021, the incidence rates were highest among women aged 60 to 64 years and men aged 65–69 years. Before the age of 55–59, the incidence rate in females was higher than that in males, while from age 65 to 69, the incidence rate in males was higher than that in females (Fig. 3A). Cancer incidence is increasing among younger individuals, particularly among women under the age of 50. The death rate was highest among individuals aged 70–74 years for males and females, and before the age of 40–44, the death rate in females was higher than that in males (Fig. 3B).

Trends in cancer rates and age-standardized changes globally. Up. The rate of cancer incidence and age-standardized changes from 1990 to 2021; below, the rate of cancer deaths and age-standardized changes from 1980 to 2021

Cancer count of different age groups and sexes globally. Up. Rate of cancer incidence by age groups from 1990 to 2021; below, rate of cancer deaths by age groups from 1980 to 2021

Across the 21 GBD regions, high-income North America exhibited the highest observed ASIR: 3138.73 (2786.29–3519.73), followed by Central Europe: 1308.53 (1147.64–1501.09) and high-income Asia Pacific: 1253.28 (1092.47–1,462.55) (Figure S2). Eastern Sub-Saharan Africa exhibited the lowest observed ASIR: 268.54 (238.04–300.85), followed by Western and Central Sub-Saharan Africa. Central Europe exhibited the highest observed ASDR: 157.77 (146.33–167.79), followed by Southern Sub-Saharan Africa: (144.19 (132.84–154.13) and East Asia: 137.08 (115.32–162.11). Furthermore, South Asia exhibited the lowest observed ASDR: 74.73 (68.77–81.23), followed by Western Sub-Saharan Africa: 89.08 (72.14–103.40), and North Africa and the Middle East: 90.11 (80.96–99.52) (Figure S3). From 1990 to 2021, Southern Sub-Saharan Africa exhibited the largest percentage increase in the rates of cancer deaths: 22% (11%–35%), while Australasia exhibited the biggest percentage decline in the rates of cancer deaths (–30%, –34% to –27%) (Table S1).

In 2021, the ASIR exhibited variations globally. Across the 204 countries, the United States of America exhibited the highest ASIR: 3,304.9 (2941.64–3699.14), followed by Canada: 1,758.48 (1470.8–2062.1) and Greenland: 1,751.13 (1468.51–2039.7). Meanwhile, Burundi exhibited the lowest observed ASIR: 243.71 (206.6–285.36), followed by Madagascar: 243.88 (207.76–281.58) and Kenya: 251.15 (218.01–287.69) (Figs. 4A and S4). Mongolia exhibited the highest observed ASDR: 214.81 (188.01, 243.86), followed by Monaco: 207.69 (173.54–245.45) and Zimbabwe: 201.33 (162.95–246.3). Furthermore, Oman exhibited the lowest observed ASDR: 44.21 (36.51–52.81), followed by the Maldives: 47.86 (39.57–56.19) and Algeria: 51.51 (43.01–61.21) (Figs. 4B and S5). Between 1990 and 2021, the United States of America exhibited the largest percentage increase in cancer incidence: 88% (78%–97%), while Burundi exhibited the biggest percentage decline in cancer incidence (–15%, –26% to –1%). Additionally, between 1990 and 2021, Lesotho (80%, 32% to 140%) exhibited the largest percentage increase in cancer-related deaths, while Kazakhstan (–50%, –56% to –44%) exhibited the biggest percentage decline in cancer-related deaths (Table S2).

ASIR and deaths rate in 204 countries and territories in 2021. A. Age-standardized incidence rate; B. Age-standardized death rate

In 2021, the high SDI quintile exhibited the highest ASIR: 1671.46 (95% UI: 1484.99–1875.02) and ASDR 123.22 (95% UI: 113.06–128.96), while the low SDI exhibited the lowest ASIR: 336.09 (95% UI: 288.48–385.96) and ASDR: 90.64 (95% UI: 79.86–102.00). Figure 5 depicts the changes in age-standardized incidence and death rates across five SDIs from 1990/1980 to 2021. The findings suggest a significant increase of ASIR and ASDR in high-SDI and high-middle SDI regions. However, low, middle, and low-middle SDIs exhibited a stable trend in ASIR and ASDR. Based on the changes in age-standardized death rates by region, the high-income North Pacific exhibited an increase in ASIR among the four regions with the highest SDI. The ASIR increased gradually as the SDI increased until it reached approximately 0.65, after which it increased significantly. However, the United States of America experienced unexpectedly high ASIR based on SDI levels (Figure S6). The ASDR value in the region level decreased as the SDI increased to approximately 0.34. Subsequently, it increased until it reached approximately 0.75, after which it decreased significantly (Figure S7).

ASIR and death rate change trends in females and males among global and sociodemographic indexes

In 2021, 4.06 million (95% UI: 3.46–4.75) global cancer-related deaths were caused by all estimated risk factors, representing 41.07% (35.24–46.64) of all cancer-related deaths for both sexes. Risk factors caused 2.56 million (95% UI: 2.20–2.99) cancer-related deaths in males and 1.50 million (95% UI: 1.16–1.83) in females, accounting for 45.65% (40.72–50.77) of all male cancer-related deaths and 35.08% (27.38–42.23) of all female cancer-related deaths. The global overall cancer DALYs attributed to estimated risk factors were 100.30 million (95% UI: 86.19–116.72) for both sexes, representing 39.59% (34.18–44.88) of all cancer DALYs. Males accounted for 62.09 million (95% UI: 53.92–72.60) cancer DALYs due to risk factors, representing 43.81% (29.81–46.07) of all cancer DALYs, while females accounted for an estimated 38.21 million (95% UI: 32.8–43.1) cancer DALYs attributable to risk factors, representing 34.21% (27.05–40.69) of all cancer DALYs in females. Global geographical pattern variations were observed for cancer age-standardized DALY rates caused by environmental and occupational, behavioral, and metabolic risks across different regions. Higher age-standardized DALY rates were observed in central Europe within these level 1 risk factor categories (Figure S8).

Tobacco was the primary level 2 risk factor for cancer DALYs in males, contributing to 29.32% (25.32–33.14) of all cancer DALYs, followed by dietary risks, alcohol use, and air pollution, which accounted for 5.89% (2.01–10.73), 5.48% (4.83–6.11), and 4.30% (2.77–5.95) of male cancer DALYs in 2021, respectively. Additionally, unsafe sex was the primary level 2 risk factor for females based on cancer DALYs. It comprised 8.88% (8.40–9.49) of all female cancer DALYs, followed by tobacco: 8.09% (6.12–10.05), dietary risks 7.21% (1.96–12.92), and high BMI 4.72% (1.86–7.59) (Figure S9).