231P - BMI-predicted progression-free survival after pembrolizumab therapy for urothelial cancer: Asian version of BMI classification is suitable for Asian patients

Background

Body mass index (BMI) has shown the associated with clinical outcomes of immune checkpoint inhibitors (ICIs) treatment in patients with several malignancies. We previously reported the association between clinical outcome in advanced urothelial carcinoma (UC) patients treated with pembrolizumab and BMI according to the WHO international classification. However, no patient in our cohort was grouped into obese (BMI 30kg/m²≤) and WHO BMI classification may be unsuitable for Asians. Therefore, we investigated the association between BMI classification developed for Asian people and clinical outcomes of pembrolizumab for advanced UC.

Methods

We retrospectively reviewed consecutive patients with advanced UC who received pembrolizumab between December 2003 and March 2023. Patients were divided into three groups based on BMI classification for Asians; the non-overweight group (BMI < 22.9 kg/m²), the overweight group (23 ≤ BMI < 24.9 kg/m²), and the obese group (BMI ≥ 25 kg/m²). Tumor response, progression-free survival (PFS), overall survival (OS), and incidence of adverse events (AEs) were compared among the groups. We additionally investigated factors associated with PFS using the multivariate analysis.

Results

Of 99 eligible patients, 54 (54.5%), 21 (21.2%) and 24 (24.2%) were in the non-overweight, overweight and obese group, respectively. PFS was significantly longer in the obese group (median 10.3 months) than that in the non-overweight (median 4.2 months) and the overweight group (median 2.3 months) (p=0.04). Multivariate analysis showed that obese was significantly associated with favorable PFS. The obese group had higher objective response rate and longer OS compared to other groups, although the difference did not reach the statistical significance. Multivariate analysis showed that obese was significantly associated with favorable PFS. There was no difference in the occurrence of irAEs among three groups.

Conclusions

BMI was associated with PFS for patients with advanced UC received pembrolizumab and BMI Asian classification may be more useful and suitable for Asian patients than that of WHO classification.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The author.

Funding

Has not received any funding.

Disclosure

The author has declared no conflicts of interest.