The effects of delayed formalin fixation on endometrial pathology in hysterectomy specimens

Opening hysterectomy specimens for pathological assessment can be performed before or after formalin fixation. The former method, preferred by most pathologists, limits the autolytic changes of the endometrium, but it may result in a distortion of the uterine wall as a result of the contraction of the myometrium. This may interfere with the assessment of the degree of tumor extension to the uterine wall. The latter method, which is less common, preserves the uterine wall but may limit the assessment of the endometrial glands due to autolytic changes, and the effect of nuclear features is unknown. In this study, we assessed 78 hysterectomy specimens opened by the second method for these changes. The autolytic changes were present in all cases, but they didn't limit the pathologist's assessment to reach the final diagnosis in both the benign and malignant cases. Although, it was difficult to determine which of the nuclear changes was caused by delayed fixation, we found nuclear rounding and prominence of the nucleoli were not features of autolytic changes. Conditions with nuclear features that may mimic mild nuclear atypia were common in these specimens, but not severe atypia. We concluded that a delayed opening of the uterus is an acceptable procedure in dealing with these specimens.