Abstract 1754P
Background
Anti-PD1/L1 ICIs are indicated for mUC, however, only a minority of patients (pts) will derive therapeutic benefit. Strong predictive and prognostic factors are lacking. Obesity causes a low grade chronic inflammatory state and has been associated with increased ICI responsiveness in some cancer types. We investigated whether elevated BMI was associated with ICI outcomes in mUC.
Methods
We performed a multi-center retrospective cohort study including 121 pts with mUC who received anti-PD1/L1 ICI for metastatic disease between 2016-2021 at 3 Canadian cancer centres. Clinical characteristics, including demographics, BMI, neutrophil to lymphocyte ratio (NLR), objective response, and survival were abstracted from chart review. ICI treatment response was determined by investigator assessment of clinical and radiologic parameters. Fisher’s exact test was used to assess differences in response rates between groups. Log rank and Cox regression models were used to assess overall survival (OS).
Results
Ninety (74%) were male, and 74 (61%) received ICI as a 2nd or later line therapy for metastatic disease. Twenty-three pts had a BMI ≥ 30, 43 had a 25 ≤ BMI < 30 and 55 had a BMI < 25. A BMI ≥ 25 was significantly correlated to a higher response rate to ICI (45.4% vs 16.3%, p=0.02). After a median follow-up of 14.5 months, pts with BMI ≥ 30 experienced significant longer median OS 24.8 months vs 14.4 months for 25 ≤ BMI < 30 and 8.5 months for BMI < 25 (p=0.012). In multivariate analysis, BMI ≥ 30 was an independent prognosis factor for OS as detailed in the table. Table: 1754P
| OS | Univariable | Multivariable | ||||
| HR | 95%CI | p-value | HR | 95%CI | p-value | |
| BMI ≥ 30 vs < 30 | 0.63 | 0.45-0.88 | 0.002 | 0.40 | 0.17-0.96 | 0.040 |
| Male vs Female | 0.95 | 0.58-1.57 | 0.867 | |||
| ECOG ≥ 2 vs 0-1 | 1.68 | 0.86-3.29 | 0.125 | 2.21 | 1.02-4.78 | 0.042 |
| ICI Line ≥ 2 vs 1 | 2.39 | 1.43-3.97 | 0.001 | 1.80 | 1.31-2.48 | 0.000 |
| NLR ≥ 4 vs < 4 | 2.46 | 1.53-3.94 | 0.000 | 2.66 | 1.58-4.49 | 0.000 |
| Bone metastasis Yes vs No | 2.38 | 1.52-3.73 | 0.000 | 1.98 | 1.17-3.35 | 0.010 |
| Lung metastasis Yes vs No | 1.88 | 1.21-2.93 | 0.005 | |||
| Liver metastasis Yes vs No | 1.92 | 1.20-3.09 | 0.006 | |||
| Age ≥ 60 vs < 60 | 1.88 | 0.65-5.45 | 0.235 |
Conclusions
Our data identified BMI, as a novel potential biomarker that is strongly and independently associated with ICI response and survival in mUC. External validation of these data in a larger study and investigations into the mechanisms behind these findings are warranted.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
University of Toronto, Division of Medical Oncology Strategic Planning Grant.
Disclosure
D.M. Jiang: Financial Interests, Personal, Invited Speaker: Janssen Oncology, Ipsen, Bayer, EMD Serono Canada, Amgen; Financial Interests, Personal, Advisory Board: EMD Serono Pfizer. C. Ferrario: Financial Interests, Personal, Invited Speaker: AstraZeneca, Bayer, Merck, Knights Therapeutics; Financial Interests, Institutional, Invited Speaker: Astellas, AstraZeneca, Lilly, Merck, Novartis, Roche-Genetech, Sanofi, Seattle Genetics, Sermonix, Zymeworks; Financial Interests, Institutional, Research Grant: AstraZeneca; Financial Interests, Institutional, Funding: Bayer; Non-Financial Interests, Advisory Role: AstraZeneca, Knights Therapeutics, Merck. R. Pezo: Financial Interests, Personal and Institutional, Advisory Board, Research Funding: Merck, Lilly, Pfizer, AstraZeneca, Daiichi Sankyo, Novartis; Financial Interests, Personal, Advisory Board: BMS, EMD Serono, Myriad, Exact Sciences; Financial Interests, Institutional, Research Grant: Ambrx Biopharma, Taiho Pharma, Zymeworks. S. Cheng: Financial Interests, Personal, Advisory Board: Merck, AstraZeneca. A. Sacher: Financial Interests, Institutional, Invited Speaker: Genentech-Roche, BMS, AstraZeneca, Amgen, Iovance, CRISPR Therapeutics, Merck, Pfizer, GSK, Spectrum, Lilly. A. Rose: Other, Personal, Other, spouse: Merck. All other authors have declared no conflicts of interest.