Obesity linked to poorer PFS in pembrolizumab-treated endometrial cancer

Among patients with endometrial cancer receiving treatment with pembrolizumab, those with obesity appear to have worse progression-free survival (PFS), according to a retrospective study.

Researchers reviewed the medical records of 179 patients (median age 65 years, 63 percent White, mean BMI 33 kg/m²) with advanced or recurrent endometrial cancer receiving pembrolizumab.

Of the patients, 46 received pembrolizumab monotherapy and 133 received pembrolizumab-containing combination therapy. More than half (55 percent) of the patients had obesity.

Cox regression analysis showed that higher BMI was associated with shorter PFS. The risk of death or progression increased by almost twofold for patients with BMI >40 kg/m² (hazard ratio [HR], 1.91, 95 percent confidence interval [CI], 1.13–3.21; p=0.014) and by 1.5-fold for those with BMI of 30–40 kg/m² (HR, 1.55, 95 percent CI, 1.02–2.35; p=0.041).

When analysis was stratified by mismatch repair (MMR) status, obesity was associated with lower objective response rates among patients with MMR-proficient tumours (BMI ≥30 vs <30 kg/m²: 38.8 percent vs 23.4 percent). On the other hand, response rates remained high across BMI categories among patients with MMR-deficient tumours.

In the subgroup of 79 patients who received the combination of pembrolizumab plus lenvatinib, both White and Black patients with obesity had poorer PFS compared with White nonobese patients (p=0.021 and p=0.035, respectively).

Overall survival did not significantly differ between obese and nonobese groups.