Pretreatment volume-based 18F-FDG PET/CT parameters as prognostic indicators in malignant peritoneal mesothelioma patients

Japanese Journal of Radiology 2026 March 21 [Link]

Kazuhiro Kitajima, Kosuke Matsuda, Hiroyuki Yokoyama, Toshiyuki Minami, Akifumi Nakamura, Kozo Kuribayashi, Takashi Kijima, Koichiro Yamakado

Abstract

Objective: This study was conducted to examine relationships of pretreatment volume-based quantitative 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) parameters with overall survival (OS) in malignant peritoneal mesothelioma (MPeM) patients.

Materials and methods: Data for 71 patients with FDG-avid MPeM who underwent pretreatment 18F-FDG PET/CT were retrospectively reviewed. The highest maximum standardized uptake value (SUVmax), metabolic tumor volume (WB MTV), and total lesion glycolysis (WB TLG) were calculated, including primary tumors and metastatic lesions. Relationships of clinicopathological factors (histological subtype, primary peritoneal disease form, abdominal nodal metastasis, extra-abdominal metastasis, treatment regimen), as well as volume-based quantitative PET/CT parameters with OS were evaluated using a Cox proportional hazards model and log-rank test.

Results: Enrolled patients underwent follow-up for a mean period of 27.6 months (range 2.1-161.2 months, median 18.9 months), during which 49 (69.0%) died. Receiver operating characteristic curve analysis and log-rank testing indicated that those with high SUVmax (≥ 6.9), WB MTV (≥ 60), or WB TLG (≥ 230) had a significantly lower OS rate than patients with a low rate (< 6.9, < 60, < 230; p = 0.0002, p < 0.0001, p < 0.0001, respectively). Univariate analysis of all patients indicated an association of diffuse peritoneal disease form (p = 0.022), high level SUVmax (p = 0.0002), WB MTV (p < 0.0001), or WB TLG (p < 0.0001) level, extra-abdominal metastasis (p = 0.079) and treatment regimen (p = 0.058) with significantly shorter OS. Additionally, multivariate analysis results confirmed high WB MTV as an independent negative predictor (hazard ratio 2.51, 95% confidence interval 0.72-13.45; p = 0.039).

Conclusions: These findings indicate that pretreatment volume-based quantitative 18F-FDG PET/CT parameters, especially whole-body MTV, may be useful as surrogate markers for MPeM prognosis.