Extra pounds may compromise survival in triple-negative breast cancer

Overweight patients with triple-negative breast cancer (TNBC) appear to have poorer prognosis compared with their normal-weight counterparts, with a study reporting that the former have shorter disease-free (DFS) and overall survival (OS).

Researchers performed a systematic review and meta-analysis of studies that evaluated body mass index in relation to TNBC outcomes. They searched multiple online databases and identified 13 studies, which involved a total of 8,944 TNBC patients, for inclusion in the meta-analysis.

Of the studies, 10 reported DFS data, 12 reported OS data, and nine examined both endpoints. The median follow-up time varied between 24 and 109 months, with an average of 54.9 months across studies. None of the studies were considered to have a high risk of bias.

Pooled data showed that relative to normal weight, overweight negatively influenced both DFS (hazard ratio [HR], 1.26, 95 percent confidence interval [CI], 1.09–1.46) and OS (HR, 1.29, 95 percent CI, 1.11–1.51).

In a Bayesian model, overweight TNBC patients were 7.4 and 9.9 times as likely as their normal-weight peers to have shorter DFS and OS, respectively.

The findings underscore the potential negative impact of a modifiable lifestyle factor in an especially vulnerable patient group already at risk of a worse prognosis due to the aggressiveness of the disease and the lack of targeted treatment options, according to the researchers.

However, the data should be interpreted in light of the possibility of publication bias, they added. More studies that use more precise measures of body fat and control for differences in possible moderating factors such as disease stage at diagnosis, chemotherapy regimen, and socioeconomic status are warranted.