Prognostic value of pretreatment 18F-FDG PET/CT metabolic parameters in esophageal high-grade neuroendocrine carcinoma: A bicenter retrospective study

The prognostic value of pretreatment [18F]FDG PET/CT parameters in esophageal cancer: a meta-analysis

OBJECTIVES

This study aims to evaluate the prognostic implications of pretreatment [18F]FDG-PET metrics in esophageal cancer patients through a meta-analysis of the existing literature.

METHODS

We carefully searched electronic databases, including PubMed and Embase, from inception to April 1, 2024, to identify studies describing the prognostic value of pretreatment PET metrics for advanced esophageal cancer. Clinical endpoints examined were overall survival (OS), recurrence-free survival (RFS)/disease-free survival (DFS), and progression-free survival (PFS). Hazard ratios (HRs) for PFS and OS were taken directly from the original reports.

RESULTS

Forty-seven publications, including 5504 patients, were included in our analysis. OS and PFS were analyzed in 31 and nine studies, respectively, and DFS/RFS was analyzed in 16 studies. The comprehensive pooled analysis revealed significant associations between metabolic parameters derived from positron emission tomography (PET) imaging and clinical outcomes. Expressly, the pooled HR indicated that patients with higher SUVmax were significantly associated with poor PFS (HR: 1.06; 95% CI: 1.01-1.12, p = 0.011) and poor RFS/DFS (HR: 1.09; 95% CI: 1.02-1.18, p = 0.019). Patients with higher SUVmean were significantly associated with poorer OS (HR: 1.07; 95% CI: 1.01-1.14, p = 0.025). High MTV was significantly associated with inferior OS (HR: 1.02; 95% CI: 1.00-1.05, p = 0.049). High TLG was significantly associated with poorer RFS/DFS (HR: 2.02; 95% CI: 1.11-3.68, p = 0.022).

CONCLUSION

This study unveiled pretreatment FDG-derived parameters as valuable prognostic indicators in assessing esophageal cancer outcomes. Specifically, SUVmax is associated with PFS and RFS/DFS. SUVmean and MTV were correlated with OS, and TLG was only associated with RFS/DFS.

KEY POINTS

Question Inconsistent findings on the prognostic value of pretreatment [18F]FDG PET parameters in esophageal cancer require comprehensive analysis to clarify their role in outcome prediction. Findings Higher pretreatment [18F]FDG-PET metrics (SUVmax, SUVmean, MTV, TLG) are associated with poor survival outcomes, emphasizing their potential value in enhancing prognostic assessments for esophageal cancer. Clinical relevance This study highlights the prognostic significance of pretreatment [18F]FDG-PET metrics in esophageal cancer, providing valuable insights for patient outcome prediction and potentially guiding personalized treatment strategies.

Volumetric Parameters Derived from CXCR4-Directed PET/CT Predict Outcome in Patients with Gastrointestinal Neuroendocrine Carcinomas

BACKGROUND

Gastro-entero-pancreatic neuroendocrine carcinomas (GEP-NECs) are an aggressive subgroup of neuroendocrine neoplasms (NENs). In patients affected with NEN, there is a growing body of evidence that increased C-X-C motif chemokine receptor (CXCR4) expression is linked to decreasing overall survival (OS) in an ex-vivo setting. Thus, we aimed to determine whether the in-vivo-derived CXCR4-directed whole-body PET signal can also determine GEP-NEC patients with shorter OS.

METHODS

We retrospectively included 16 patients with histologically proven GEP-NEC, who underwent CXCR4-directed PET/CT for staging and therapy planning. We assessed maximum, peak, and mean standardized uptake values as well as whole-body tumor volume (TV) and total-lesion uptake (TLU = SUVmean × TV) using a semi-automatic segmentation tool with a 50% threshold. Association of PET-based biomarkers and OS or radiographic progression-free survival (rPFS; according to RECIST 1.1 criteria) was analyzed using univariable and multivariable cox regression.

RESULTS

Median OS and rPFS was 7.5 and 7 months, respectively. A significant correlation between TV and TLU was found for OS (TV: hazard ratio (HR) 1.007 95% confidence interval (CI) 1.000-1.014, p = 0.0309; TLU: HR 1.002 95% CI 1.000-1.003, p = 0.0350) and rPFS (TV: HR 1.010 95% CI 1.002-1.021; p = 0.0275; TLU: HR 1.002 95% CI 1.000-1.004, p = 0.0329), respectively. No significant correlation with OS or rPFS was found for non-volumetric parameters (p > 0.4). TV remained a significant predictive marker for OS and rPFS in multivariable analysis (OS: HR 1.012 95%, CI 1.003-1.022, p = 0.0084; rPFS: HR 1.009, 95% CI 0.9999-1.019, p = 0.0491), whereas TLU remained only prognostic for OS (HR 1.009, 95% CI 0.9999-1.019, p = 0.0194) but narrowly failed significance for rPFS (p = 0.0559).

CONCLUSION

In-vivo assessment of CXCR4 PET-derived volumetric parameters is predictive for outcome of patients with GEP-NEC and could be used as a risk stratification tool, which detects patients prone to early progression.

A Case of Primary Esophageal Sarcomatoid Carcinoma Detected by 18F-FDG PET/CT

ABSTRACT

Primary sarcomatoid carcinoma of the esophagus is a rare and highly malignant neoplasm with a poor prognosis. A 51-year-old man presented with difficulty in swallowing for 2 weeks. Thoracic CT revealed a huge mass in the middle-lower thoracic esophagus. 18F-FDG PET/CT showed intense 18F-FDG uptake of the esophageal tumor. Histopathology and immunohistochemistry of the esophageal lesion tissue confirmed the diagnosis of sarcomatoid carcinoma after postoperative pathological biopsy.