Evaluation of Preoperative Chest Imaging in Low-Risk Endometrial Cancer Patients

Current national guidelines recommend preoperative thoracic imaging for all patients undergoing surgery for endometrial cancer. The objective of this project was to report the incidence of pulmonary metastasis in endometrial cancer patients and describe tumor and patient characteristics to better identify a low-risk population for thoracic involvement. We evaluated the ideal modality of preoperative imaging for both low-risk and high-risk populations based on the risk of pulmonary involvement.

A retrospective cross-sectional study of patients undergoing surgical evaluation for endometrial cancer at a single institution from 2010 to 2014 was performed. Low-risk patients were defined as having a preoperative pathology sample showing grade 1 or 2 endometrioid endometrial cancer and a physical examination not concerning for extrauterine disease spread.

A total of 352 patients were evaluated, of which 327 (92.9%) had preoperative thoracic imaging. Twenty-six patients had benign pathology or no preoperative sampling, leaving 301 patients for analysis. There were 228 (75.7%) of 301 patients classified as low-risk by our criteria. There were 20 (8.8%) of 228 low-risk patients with initial imaging concerning for pulmonary metastasis, but follow-up showed no evidence of disease. No low-risk patients (0/228; 95% confidence interval [CI], 0%-0.02%) had pulmonary metastasis. There were 4 (1.3%) of 301 (95% CI, 0%-0.04%) patients diagnosed with pulmonary metastasis based on preoperative imaging, and 4 (1.3%) of 301 (95% CI, 0.01%-0.04%) patients with recurrent pulmonary disease. Median time to pulmonary recurrence was 20 months.

The incidence of pulmonary metastasis found on preoperative imaging is exceptionally low in our defined low-risk population. All of the patients with pulmonary involvement either initially or upon recurrence had high-risk features. Given our findings, we would recommend that providers consider chest x-ray as the appropriate screening modality for the low-risk population and chest computed tomography for the high-risk population.