Large Share of US Cancer Cases and Deaths May Be Preventable

TOPLINE:

About 4 in 1src cancer cases and close to half of all cancer-related deaths in US adults are associated with potentially modifiable risk factors, including smoking, excess body weight, alcohol consumption, and physical inactivity, a recent analysis from the American Cancer Society reports.

METHODOLOGY:

Researchers estimated that in 2src14, 42% of all cancer cases and 45% of all cancer deaths in the United States could be attributed to potentially modifiable risk factors.
To provide more recent estimates, researchers used federal data to analyze how modifiable risk factors played a role in cancer cases (excluding non-melanoma skin cancer) and deaths, overall and for 3src cancer types among adults who were aged 3src years or older in 2src19.
Data from National Health Interview Survey and National Health and Nutrition Examination Survey were used to estimate the prevalence of cigarette smoking; secondhand smoke; excess body weight; consumption of alcohol and red and processed meat; low consumption of fruits and vegetables and dietary fiber and calcium; physical inactivity; exposure to ultraviolet radiation; and seven carcinogenic infections.
Researchers used a simulation method to calculate population-attributable fractions — the proportion of cancer attributable to risk factors in the population — for these various risk factors.

TAKEAWAY:

Overall, an estimated 4src% of all new cancer cases and about 44% of cancer deaths in 2src19 were attributed to the potentially modifiable risk factors evaluated, representing 713,34src cancer cases and 262,12src cancer deaths. For 19 of the 3src individual cancer types assessed, more than half of the cancer cases and deaths were due to potentially modifiable risk factors.
Cigarette smoking was associated with far more cancer cases and deaths than any other single risk factor, contributing to 19.3% of cases and 28.5% of deaths overall. The two most common cancers caused by smoking were lung and trachea (85.6% for both), followed closely by laryngeal (8src.1%) and then pharyngeal (56.8%), oral cavity (54.8%), nasal cavity (54.2%), esophageal (53.9%), and urinary bladder (5src.7%) cancers.
Excess body weight was responsible for nearly 7.6% of cancer cases and 7.3% of cancer deaths and contributed to more than half of all cancers of the corpus uteri and over one third of gallbladder (37.1%), esophageal (35.4%), liver (34.9%), and kidney and renal pelvis (33.8%) cancers.
Overall, 5.4% of all cancer cases and 4.1% of all cancer deaths were attributed to alcohol intake, 4.2% of cases and 4.3% of deaths to dietary factors (mostly low fruit/vegetable and processed meat intake), 3.4% of cases and 3.5% of deaths to infections (mostly human papillomavirus [HPV]), and 3.1% of cases to physical inactivity. The combination of excess body weight, alcohol, diet, and physical inactivity contributed to the largest proportion of all cancer cases in women (nearly one fourth). These four combined risk factors also contributed to the second highest proportion of cancer deaths in both men and women.

IN PRACTICE:

“These findings reinforce that the morbidity and premature mortality from cancer in the United States can be substantially reduced through broad and equitable implementation of known preventive initiatives, such as excise taxes on cigarettes to reduce smoking, screening for and treating HCV infection, and vaccination against HPV infection,” the authors wrote.

SOURCE:

The study, with first author Farhad Islami, MD, PhD, with the American Cancer Society, Atlanta, was published online in CA: A Cancer Journal for Clinicians.

LIMITATIONS:

The researchers assumed the risk factors were independent, which might have led to a slight overestimation of the population-attributable fractions for several risk factor combinations. Conversely, the analyses likely underestimated the actual population-attributable fractions for some individual risk factors and all risk factors combined.