Relación entre el estado de HER2 adquirido a partir de los datos patológicos y los parámetros metabólicos obtenidos mediante [18F]FDG PET/TC pretratamiento en adenocarcinomas gástricos

Abstract

Objective

Overexpression of Human Epidermal Growth Factor Receptor 2 (HER2) is thought to be more aggressive in gastric cancer. This study aimed to evaluate the predictability of HER2 status and other prognostic pathologic parameters using [¹⁸F]FDG PET/CT and to investigate its impact on survival.

Methods

Pretreatment metabolic parameters measured by [¹⁸F]FDG PET/CT as a prognostic factor were retrospectively evaluated in 117 HER2-analysed patients. The relationship between pathological data, tumor metabolic characteristics, and distant metastases was examined, and the effect on survival was investigated.

Results

Among the 117 patients, 17.1% were HER2-positive (HER2⁺), and 82.9% were HER2-negative (HER2⁻). There was no significant association between PET/CT parameters in the HER2⁺ and HER2⁻ patient groups. HER2⁺ patients had higher 1- and 3-year survival expectations than HER2⁻ patients (80-37.9%; 47.5-20%; respectively). There was no statistically significant difference in overall survival. In Cox-regression analysis, while the presence of vascular invasion, local invasion, and distant metastasis were poor prognostic factors, HER2 was not a prognostic factor. Vascular invasion and local invasion (T3/T4) were also associated with higher SUVmax values. Patients with distant metastases had significantly higher SUVmax, SUVmean, and TLG.

Conclusion

This study showed no association between HER2 expression and [¹⁸F]FDG PET/CT metabolic parameters. However, regardless of HER2 status, the results indicated distant metastasis, local invasion, and vascular invasion could be associated with primary tumor metabolism. PET/CT parameters predict tumor aggressiveness and disease prognosis better than HER2 status.