(HealthDay)—For patients with human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (mBC) treated with pertuzumab and/or trastuzumab emtansine (T-DM1), a body mass index (BMI) of ≥30 kg/m² is associated with worse overall survival but does not affect progression-free survival to first-line chemotherapy (PFS1), according to a study published online Jan. 15 in the Journal of Cellular Physiology.

Eriseld Krasniqi, M.D., from the IRCCS Regina Elena National Cancer Institute in Rome, and colleagues examined the influence of BMI on clinical outcomes of 709 patients with HER2+ mBC treated with pertuzumab and/or T-DM1. The influence of BMI was further analyzed among 575 women who progressed to first-line chemotherapy.

The researchers found that BMI had no impact on PFS1 overall, while BMI ≥30 kg/m² was associated with significantly worse overall survival. BMI ≥30 kg/m² had a detrimental effect on overall survival for the women within PFS1 quartile I (PFS1 no more than six months) in a univariate analysis. In a multivariable analysis, the results were confirmed. According to PFS1 quartiles, within six months of therapy, a higher percentage of patients with high BMI and low disease burden progressed.

"In this particularly challenging battlefield, namely, in the HER2+ metastatic breast cancer, a well-depicted patient profile, including details on body mass index and its prognostic relevance, can help inform therapeutic decisions," Krasniqi said in a statement.

Several authors disclosed financial ties to the pharmaceutical industry.

More information: Abstract/Full Text (subscription or payment may be required)

Journal information: Journal of Cellular Physiology 

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