We sought to assess the number of blocks that should routinely be submitted for microscopic examination of omentectomy specimens associated with neoplasms that involve the female genital tract.
Clinicopathologic data were retrospectively reviewed in 1055 cases wherein the omentum was resected for possible gynecologic cancer staging. We investigated any associations between the microscopic positivity rate (MPR) and the number of blocks submitted, block groups (categorized as 1-2 blocks, 3-4 blocks, 5-6 blocks, and >6 blocks), and block to size ratio (the number of blocks submitted to the widest specimen dimension, classified as approximate deciles).
Of the 1055 cases we studied, 536 (50.8%) were grossly normal, and 519 (49.2%) were abnormal. Within the grossly normal group, there were no statistically significant differences in MPR between the block groups and between cases with 1, 2, 3, 4, 5, or 6 blocks submitted (P > .50 for all pairwise comparisons). Cochran-Armitage tests for trend did not show any linear trend between increasing block groups (P = .88) or increasing block to size ratios (P = .39) and MPR; a binomial logistic regression analysis confirmed that neither block groups (odds ratio, 1.144 [95% CI, 0.794-1.648]; P = .47) nor block to size ratio (odds ratio, 1.022 [95% CI, 0.770-1.358]; P = .88) showed a statistically significant linear relation to MPR. For diffusely or multifocally abnormal cases, the highest MPR (95.5%) was reached at the 1 to 2 blocks group level, and MPR did not statistically significantly increase with higher levels of sampling.
Submitting 1 to 2 block sections of the omentum in the studied setting results in an MPR that is not statistically significantly lower than the MPR associated with higher levels of sampling.