What are the lifetime odds of developing any type of cancer by age and sex?
Executive summary
Available U.S. estimates place the lifetime probability of being diagnosed with invasive cancer at roughly 39% for women and 40% for men (about 38.9%–41% overall depending on the source and method) [1] [2] [3]. Risk rises sharply with age — incidence rates are concentrated in older adults and the cumulative risk increases until about age 70, then levels or declines slightly in some datasets — and sex, smoking status, geography and method of calculation all change the headline number [4] [2] [5] [6].
1. What “lifetime risk” means and why numbers differ
“Lifetime risk” here is a statistical estimate of the probability someone will be diagnosed with cancer if current age‑specific rates apply over their remaining lifetime; different organizations use different datasets, included cancers (for example excluding most non‑melanoma skin cancers), and modeling choices, so numbers vary. The SEER/DevCan approach and American Cancer Society (ACS) modeling are commonly used; SEER reports a combined lifetime risk of about 38.9% based on 2018–2021 data (excluding 2020) while other publications cite ~41% for the U.S. depending on inclusion criteria [1] [2] [3]. The surveillance DevCan tool explicitly warns that estimates extrapolate what would happen if current rates held over a lifetime [7].
2. Sex differences are small for overall risk but vary by cancer type
Aggregate lifetime probabilities for all invasive cancers are similar for men and women: one ACS analysis reports 39.9% for men and 39.0% for women (very slightly higher for men) [3]. However, sex differences are large for specific cancers (for example prostate in men, breast in women) and overall sex gaps vary by region and cancer mix — global analyses show regions where male risk exceeds female risk by >10 percentage points [6] [3].
3. Age is the dominant factor: how risk accumulates over time
Cancer incidence rises steeply with age; population incidence by age (all cancers combined) shows most diagnoses occur in older adults, and cumulative risk increases up to around age 70 with some datasets showing a slight decline afterward because competing risks (death from other causes) remove people from the at‑risk population [4] [2]. DevCan and SEER provide age‑conditional probabilities (probability of developing cancer within the next 10, 20, 30 years or for the remainder of life if cancer‑free at a given age) for precise age windows [2] [7].
4. Smoking and other risk factors materially change lifetime risk
Smoking greatly increases lifetime risk of cancer death and also affects incidence. Pooled cohort data show at age 45 the lifetime risk of dying from cancer for male smokers was 27.7% versus 15.8% for male non‑smokers; female smokers at age 45 had higher lifetime cancer death risk than female non‑smokers as well [5]. This illustrates that behavioral exposures (smoking, HPV, etc.) and preventive actions materially change individual risk even if headline lifetime probabilities refer to the general population [5] [2].
5. Geographic and temporal variation — global vs U.S. figures
Global lifetime probabilities differ markedly by region and Human Development Index: GLOBOCAN‑based estimates found about 1 in 4 people worldwide would develop cancer in their lifetime in 2020, with Australia/New Zealand near 1 in 2 and Western Africa near 1 in 10; these stark contrasts reflect differences in age structure, exposures, and cancer detection [6]. U.S. figures (roughly 39%–41%) are higher than global averages because of older population structure and detection patterns [6] [1] [3].
6. Data caveats, methodological limits, and interpretation guidance
All lifetime risk models assume current age‑specific rates continue unchanged; DevCan cautions about extrapolation and competing risks [7]. SEER notes some years (e.g., 2020) are excluded or adjusted due to COVID impacts on data [1]. ACS and SEER use different source windows, age standardizations and exclusions (in situ vs invasive, non‑melanoma skin cancers), creating small but meaningful differences in headline percentages [3] [1].
7. What readers should take away for personal decision‑making
Headline lifetime odds (≈39%–41% in the U.S.) are useful for population context but do not substitute for individualized risk assessment: age, sex, smoking, family history, genetics (e.g., BRCA for breast cancer), HPV status, and geography all shift an individual's outlook [5] [6] [8]. For precise, age‑conditional probabilities or site‑specific lifetime risks, use SEER/DevCan or ACS tools and consult clinicians who can interpret these estimates for individual circumstances [7] [9].
If you want, I can pull specific lifetime‑risk tables by age band and sex from SEER/DevCan or the ACS reports cited here to give precise numbers (for example conditional risk at ages 20, 40, 60, 70) and note which cancers contribute most to those totals [7] [3].