TOPLINE

A US cohort study of nearly 50,000 women found no consistent association between talc-based body powder use and incident lung cancer. However, certain subgroup analyses suggested a positive association with underarm use.

METHODOLOGY

• Occupational exposure to talc, which can contain asbestos, has been linked to lung cancer, while consumer use of talc-based body powders has been associated with certain other cancers. Talc-powder particles can be inhaled deeply into the lungs, but studies have not correlated use of talc products with lung cancer risk. 
• To investigate, researchers analyzed data from the Sister Study, a prospective cohort of 49,592 US women aged 35-74 years, all of whom had a sister diagnosed with breast cancer. Participants completed baseline questionnaires about personal talc use in the 12 months prior to enrollment in 2003-2009, and at ages 10-13 years. 
• The researchers examined the association between talc use (including frequency and location on the body) and incident lung cancer, with adjustment for childhood socioeconomic status, race/ethnicity, birth cohort, smoking status, and environmental tobacco smoke. Models for adult talc use additionally adjusted for adult socioeconomic status, BMI, alcohol consumption, and region of residence.
• Sensitivity analyses were conducted limited to never-smokers (27,814 participants with 121 cases) and separately considered medically confirmed lung cancer (487 cases) or lung adenocarcinoma (211 cases). 

TAKEAWAY

• Overall, any talc use was not associated with lung cancer, with an adjusted hazard ratio [HR] of 0.94 (95% CI, 0.80-1.10) for adolescent use and 0.91 (95% CI, 0.78-1.07) for adult use. There was evidence of differences by application site or frequency. 
• However, among never-smokers, underarm talc use in adolescence was positively associated with incident lung cancer (HR, 1.55; 95% CI, 1.04-2.32), although associations were inconsistent by frequency of use. 
• In addition, frequent underarm talc use in adulthood was suggestively positively associated with medically confirmed adenocarcinoma (> 1 time/month: HR, 1.38; 95% CI, 0.91-2.10; P for trend = .21). Similarly, there was a suggestive positive association between underarm talc use during adolescence and adenocarcinoma (HR for any use, 1.21; 95% CI, 0.90-1.64). 
• Talc powder use was common across the study group, with just under half of participants reporting it in adolescence and about 40% reporting use in the year prior to enrollment. There were no significant differences in use between lung cancer cases and noncases. 

IN PRACTICE

“This analysis does not support an association between talc use and lung cancer, although some subgroup findings may warrant further investigation,” the study authors wrote. However, they added, “considering imprecise effect estimates and inconsistent dose-response patterns, we observed little evidence to support a true effect.”

SOURCE

The study was led by Katie M. O’Brien, MSPH, PhD, of the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. It was published online in Cancer Epidemiology, Biomarkers & Prevention.

LIMITATIONS

The study relied on self-reported talc use, which may be subject to recall bias and measurement error, and there was no information on the chemical composition of talc-based products. The relatively small number of cases in subgroup analyses, particularly among never-smokers and for histologic subtypes like adenocarcinoma, limits statistical power. The population consisted of women who had a sister with breast cancer, which may limit generalizability.

DISCLOSURES

The National Institutes of Health funded the study. One author disclosed support from DLH Corp during the conduct of the study. No other disclosures were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.