Histopathology Discrepancy of Preoperative Endometrial Sampling and Final Specimen: How Does This Influence Selective Lymph Node Dissection?

OBJECTIVE: Preoperative histology is a major component in the perioperative selective lymph node (LN) dissection decision process. Discrepancy between preoperative endometrial sampling and final specimen histopathology is generally accepted. The goals of this project are to determine if discrepancy of histopathology is associated with alteration of adjuvant treatment or outcome. MATERIALS AND METHODS: We performed a retrospective cross-sectional analysis of all patients undergoing surgery for endometrial cancer at a single institution from 2010 to 2014. All patients had preoperative endometrial sampling. Histopathology discrepancy was evaluated for potential in variation of perioperative LN dissection. Criteria for not performing LN dissection was defined as preoperative endometrioid histology, grade 1 or 2 lesion, myometrial invasion of 50% or less, and primary tumor diameter 2 cm or less. RESULTS: A total of 352 patients were identified; 44 were excluded because of no preoperative pathology or no residual disease on final pathology. Discrepancy of histopathology was noted in 64/308 (20.8%; 95% confidence interval [CI], 16.2%-25.3%) patients. Preoperative endometrioid histology was noted in 272 patients, and 17/272 (6.3%; 95% CI, 3.4%-9.1%) had preoperative sampling reviewed as a grade 1 or 2 endometrioid lesion and final specimen was upgraded to grade 3. Downstaging occurred in 3/272 (1.1%; 95% CI, 0%-2.3%) patients with preoperative grade 3 lesion and final specimen demonstrated grade 1 or 2 disease. All 3 patients' primary tumor diameter was greater than 2 cm and therefore received LN dissection. Histopathological discrepancy that would alter perioperative LN dissection decision based on the aforementioned criteria occurred in 2/272 (0.7%; 95% CI, 0%-1.8%). CONCLUSIONS: Despite a 20% discrepancy of preoperative and postoperative histopathology, discrepancy that would alter a perioperative decision for LN dissection occurs in only 0.7% of cases in this retrospective single-institutional experience. Myometrial invasion and tumor size may be more influential than histology in LN selection criteria.

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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.