Abstract 532P
Background
Immune checkpoint inhibitors (ICIs) have come to be used for the treatment of the patients with malignant pleural mesothelioma (MPM). Although modified RECIST (mRECIST) criteria is the standard method to evaluate the antitumor efficacy of ICIs, it is sometimes difficult to distinguish progressive disease from pseudoprogression (PsPD). While serum soluble mesothelin related peptide (SMRP) is commonly known as a specific tumor marker of MPM, the significance of SMRP levels in determining the efficacy of ICI treatment has not been established.
Methods
We investigated the relationship between changes of serum SMRP levels and treatment response in MPM patients treated with ipilimumab plus nivolumab combination therapy at our hospital between June 2021 and January 2023.
Results
Twenty-eight patients were included in the study. Median age was 75 years (59-85). The number of histological subtypes of epithelioid, sarcomatoid, biphasic and desmoplastic were 18, 6, 3 and 1, respectively. Treatment response was evaluated by mRECIST. The number of patients who achieved partial response (PR), stable disease (SD) and progressive disease (PD) were 9, 16 and 3, respectively. Among 25 patients with PR and SD, PsPD was observed in 5 patients (PR/SD: 3/2). The median serum SMRP before treatment in all patients was 0.90 nmol/L (0.4 - 16.9)., and the change from baseline at the time of first evaluation was +0.1 nmol/L (-4.5 - +24.5), The median change of serum SMRP level from baseline in patients with PR, SD, PsPD and PD was 0.0 nmol/L (-1.0 - +1.4), +0.1 nmol/L (-4.5 - +4.5), +0.2 nmol/L (-0.9 - +0.9) and +19.5 nmol/L (+0.1 - +24.5), respectively. These results indicated that serum SMRP level in patients with PD already tended to increase at the time of first evaluation.
Conclusions
Our results suggested that changes in serum SMRP levels was useful in determining the efficacy of ICI treatment. We are planning to accumulate more cases in the future for further investigation.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
26P - Subcutaneous trastuzumab versus intravenous trastuzumab for treatment of patients with HER2-positive breast cancer: A time, motion and cost-benefit assessment in a day care oncology unit in China
Presenter: Bei Sun
Session: Poster Display
Resources:
Abstract
27P - The biological characteristics of HER2-low in TNBC using mRNA profiling and molecular subtypes
Presenter: Asako Tsuruga
Session: Poster Display
Resources:
Abstract
28P - One-week ultra-hypofractionated partial breast RT in early breast cancer: 3DCRT vs IMRT
Presenter: Nurilla Zaynutdinov
Session: Poster Display
Resources:
Abstract
30P - Stereotactic body radiotherapy using cyberknife versus interstitial brachytherapy in accelerated partial breast irradiation on left-sided breast: A comparison of preliminary clinical result and dosimetric characteristics
Presenter: Ting-Na Wei
Session: Poster Display
Resources:
Abstract
31P - Prognostic implication of breast edema on preoperative breast MRI in breast cancer
Presenter: Ki-tae Hwang
Session: Poster Display
Resources:
Abstract
32P - Efficacy of olanzapine in the prophylaxis of delayed chemotherapy-induced nausea and vomiting in breast cancer patients receiving dose-dense AC with a steroid-sparing regimen: A single-center pilot study
Presenter: Manami Tada
Session: Poster Display
Resources:
Abstract
34P - Social support as the mediator of the association between unmet needs and happiness among women with early breast cancer
Presenter: Nithiya Sinarajoo
Session: Poster Display
Resources:
Abstract
35P - Prospective study assessing the efficacy and safety of a scalp cooling device for the prevention of alopecia in breast cancer patients undergoing (neo)adjuvant chemotherapy
Presenter: Winnie Yeo
Session: Poster Display
Resources:
Abstract
37P - To excise or not to excise: Preventive management of early breast cancer in atypical ductal hyperplasia patients
Presenter: Clarisse Hing
Session: Poster Display
Resources:
Abstract
38P - Exploring prognostic factors in patients achieving PCR after neoadjuvant therapy for triple-negative breast cancer: A retrospective study based on SEER data
Presenter: Lv Wenjie
Session: Poster Display
Resources:
Abstract