D&C has the best concordance between preoperative and postoperative grades among morbidly obese endometrial cancer patients

Aim: Endometrial cancer is diagnosed by obtaining uterine biopsies by pipelle, dilatation and curettage (D&C), or hysteroscopy. In 15%–25% of the cases, the preoperative and postoperative grades do not match. This discrepancy may carry significant clinical and prognostic consequences. We aimed to assess how body mass index (BMI) affects preoperative and postoperative grade mismatches and whether biopsy methods mitigate this effect. Methods: We conducted a retrospective review of patients with endometrial cancer who underwent surgery at our center between 2014 and 2022. We stratified patients into six classes of BMI based on the WHO classification. Preoperative and postoperative grades were compared for concordance with regards to patient BMI and sampling method. Results: A total of 158 patients were included, diagnosed by pipelle (n = 99), hysteroscopy (n = 15), or D&C (n = 44). For all methods, every unit increase in BMI increased the odds of having a gap between histology grades by 5.2%. In the pipelle group, the odds of a larger gap between the histology grades was 62% higher than that of women in the other groups. Among the D&C group, the odds of having a bigger difference between histology grades were 91.8% lower compared to the other groups. Patients with BMI over 30 had nearly 50% discrepancy when diagnosed with pipelle or hysteroscopy, but less than 10% with D&C. Conclusions: Increasing BMI is associated with decreasing concordance between preoperative and postoperative grades in endometrial cancer, especially when it exceeds 30. This effect is much less pronounced, however, when the diagnostic method is D&C.