Diagnostic performance of somatostatin receptor imaging by PET/CT in patients with cardiac sarcoidosis: a systematic review and meta-analysis

Abstract Funding Acknowledgements Type of funding sources: None. Backgrounds Somatostatin receptor (SSTR) based positron emission tomography/computed tomography (PET/CT) is a novel approach for detecting myocardial inflammation and, consequently, cardiac sarcoidosis (CS). However, the diagnostic performance of SSTR PET/CT was only evaluated in small studies. Purpose To evaluate the clinical performance of SSTR PET/CT in diagnosing CS. Methods PubMed, Embase, and Cochrane Library were searched from the earliest available date of indexing to December 2022 for studies evaluating the SSTR PET/CT for the evaluation of possible CS defined by the Japanese Ministry of Health, Labour and Welfare (JMHW) criteria. Studies were eligible if they were performed on patient level. The case reports and reviews were excluded. To calculate the overall performance of the diagnostic accuracy of SSTR PET/CT, a summary receiver operating curve (SROC) was done. The sensitivities and specificities of eligible studies were pooled. Heterogeneity was evaluated with the I² test. Sensitivity analysis excluding outliers was conducted. Results Six studies used SSTR PET/CT involving 104 patients (mean age 50 years, 45% male) fulfilled the inclusion criteria. All included studies used 68Ga-DOTATOC analogue. The pooled sensitivity of SSTR PET/CT for diagnosis of CS was 75.6% (95% CI 36.5–94.4%; I² = 34%), and the pooled specificity was 97.6% (95% CI 84.9–99.7%; I² = 0%) (Figure 1). SROC analysis demonstrated good overall accuracy for SSTR PET/CT (Figure 2). Moreover, the sensitivity analysis of SSTR PET/CT (5 studies) showed a pooled sensitivity of 80% (95% CI 58.9–92.5%; I² = 0%) and a pooled specificity of 97.1% (95% CI 82.3–99.6%; I² = 0%). Conclusions SSTR PET/CT is a useful adjunctive diagnostic tool in evaluating CS. Further large multi-center studies are warranted to validate the diagnostic accuracy of SSTR PET/CT for the diagnosis of CS. Figure 1: Sensitivity/specificity plots Figure 2: SROC curve