The headline numbers tell a story of genuine progress. In 1990, roughly 30,700 women of reproductive age were diagnosed with TBL cancer globally; by 2021 that figure had risen to about 45,900. Yet when adjusted for the age structure of the population, the incidence rate actually fell, from 2.73 cases per 100,000 women to 2.23 per 100,000—an estimated annual percentage change of −0.81 percent. Mortality tells a similar tale. Deaths rose in absolute terms, from about 26,100 to nearly 34,900 over the three decades, but the age-standardised death rate dropped from 2.32 to 1.70 per 100,000, an annual decline of 1.21 percent. The DALY rate, which combines years of life lost with years lived in disability, fell from 111.8 to 81.8 per 100,000 over the same period.

What makes these trends particularly striking is their shape. Rather than declining steadily, all three indicators followed a rise-then-fall trajectory. Incidence peaked in 2001, mortality in 2000 and DALYs in 1996, with the steepest declines occurring between 2010 and 2016. The researchers attribute this pattern to the long lag between smoking exposure and cancer development. Male smoking rates began falling immediately after the Second World War, while female rates rose after the war and only started to decline in the late 1960s. That delay pushed the peak of the lung cancer epidemic in women well behind that of men, and the timing of the observed peak in reproductive-age women fits this historical fingerprint precisely.

Beneath the averages, the biology of lung cancer in women is markedly different from that in men, and the study’s authors argue this has been underappreciated. Women who smoke face roughly three times the lung cancer risk of men who smoke at equivalent exposure, with higher levels of DNA adducts in lung tissue and a greater propensity for p53 and K-RAS mutations. The mechanism involves estrogen: the hormone can synergise directly with tobacco carcinogens such as benzo[a]pyrene, and estrogen receptor alpha upregulates the expression of CYP1A1 and CYP1B1, enzymes that metabolically activate polycyclic aromatic hydrocarbons in cigarette smoke. CYP1A1 expression in the lungs of female smokers can be nearly four times higher than in male smokers. Compounding this, women have comparatively weaker DNA repair capacity, allowing mutations to accumulate more readily.

Smoking, however, is only part of the picture for this population. Globally, about one-third of households still rely on biomass or coal for cooking, heating and lighting, and women of reproductive age bear the brunt of that exposure because they are typically responsible for preparing meals. In China, where fewer than 5 percent of women smoke, as many as 81.65 percent of female lung cancer cases are attributed to risk factors other than tobacco, with outdoor air pollution and indoor burning of solid fuels considered major contributors. A systematic review and meta-analysis cited in the study found that the lung cancer risk associated with solid fuel use is significantly higher among women, with an odds ratio of 1.81 compared with 1.16 for men. Exposure assessments in India have shown that women aged 15 to 40 who cook with solid fuels register the highest 24-hour average exposure concentrations of any household group.

The geographic distribution of the burden is profoundly uneven. Among the 21 GBD regions, East Asia recorded the highest incidence and mortality rates in 2021, at 4.75 and 3.39 cases per 100,000 respectively, a situation the researchers link to rapid economic development, lifestyle changes, high secondhand smoke exposure despite low female smoking rates, and indoor air pollution from cooking fumes and solid fuels. At the country level, Greenland had the highest incidence rate at 7.94 per 100,000, while Monaco recorded the highest mortality rate at 7.65 per 100,000. Nigeria had the lowest rates for both measures. China, by virtue of its enormous population, led the world in absolute case numbers, deaths and DALYs in both 1990 and 2021.

Stratifying the data by the Socio-Demographic Index—a composite measure of income, education and fertility—exposes a stark divergence. Only in low-SDI and lower-middle-SDI regions did incidence and mortality rates continue to rise between 1990 and 2021, while high-SDI regions saw accelerating declines from around 2010 onward. South Asia recorded the fastest-growing rates across all indicators, with an incidence EAPC of 1.53 percent, whereas high-income North America showed the steepest declines, at −2.83 percent for incidence and −3.22 percent for mortality. The researchers describe lower-middle-SDI regions as being in an

Subject of Research: Global burden and trends of trachea, bronchus and lung cancer in women of reproductive age from 1990 to 2021 with projections to 2035

Article Title: Trachea, bronchus, and lung cancer in women of reproductive age: global burden trends from 1990 to 2021 and forecasts to 2035

Article References: Trachea, bronchus, and lung cancer in women of reproductive age: global burden trends from 1990 to 2021 and forecasts to 2035. (n.d.). https://doi.org/10.3389/fgwh.2026.1695260

Image Credits: AI Generated

DOI: 10.3389/fgwh.2026.1695260

Keywords: lung cancer, women's health, Global Burden of Disease, reproductive age, health inequality, tobacco control, air pollution, DALYs, Bayesian modelling, socio-demographic index, epidemiology, cancer projections