Association between chronic stress-related amygdala metabolic activity and lymph node metastasis in endometrial cancer

Chronic stress's link to endometrial cancer risk and tumor aggressiveness remains unclear. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) is a well-established technique for evaluating the metabolic activity of the amygdala (AmygA), a crucial brain region involved in the response to chronic stress. We aimed to investigate the association between AmygA and lymph node (LN) metastasis in patients with endometrial cancer. In total, 161 patients with newly diagnosed endometrial cancer who received preoperative ¹⁸F-FDG PET/CT were recruited. AmygA was calculated as the ratio of the maximum standardized uptake value (SUVmax) of the amygdala to the mean standardized uptake value (SUVmean) of the temporal lobe. Postmenopausal patients with positive LN metastasis had elevated AmygA levels and systemic inflammation markers, such as spleen and bone marrow SUVmax, compared to those without LN metastasis. Notably, AmygA was independently associated with LN metastasis in postmenopausal patients but not in premenopausal patients. Additionally, the correlation between AmygA and systemic inflammation markers was more pronounced in postmenopausal patients. AmygA is independently associated with LN metastasis status in postmenopausal endometrial cancer patients. Our findings suggest that neurobiological activity related to stress, particularly involving the amygdala, may be associated with tumor aggressiveness in postmenopausal endometrial cancer patients.