Insufficient and Scant Endometrial Samples: Determining Clinicopathologic Outcomes and Consistency in Reporting

There are no widely accepted pathologic criteria for reporting endometrial samples with limited tissue and no consensus on the clinical follow-up of patients with these samples. Our study compares clinicopathologic outcomes and determines reporting consistency for these samples. This was done in 3 parts: (1) retrospective chart review of all patients with reported insufficient or scant endometrial samples from 2010 to 2013 at our center to determine repeat sampling and final pathologic diagnosis; (2) survey of gynecologists about their practice for managing patients with these samples; (3) blind review of 99 cases of previously reported scant or insufficient samples in which 4 reviewers separately reassigned cases as scant, insufficient, or diagnostic. Agreement was determined across reviewers. For part (1): 1149 patients had insufficient (49%) or scant (51%) samples with no significant difference in repeat biopsy rate (33% vs. 31%; P=0.33). Final diagnosis of uterine malignancy was higher in patients with a previous insufficient sample than with scant (19% and 9%, respectively), but this was not statistically significant. For part (2): among gynecologists surveyed, 4 of 5 reported managing patients with insufficient or scant samples similarly. For part (3): complete consensus across raters occurred in 57% of cases (Fleiss κ, 0.4891). Similar repeat biopsy rates between scant and insufficient samples suggest that our clinicians choose similar management for both terminologies. As such, distinction between insufficient and scant samples may not be necessary in pathologic reporting. Given the malignancy outcomes, both groups merit repeat sampling in the appropriate context.