Stepping on diagnosis with step sections- An institutional experience

Introduction: A thorough morphological assessment plays a central role in evaluation of skin biopsies. Overlapping microscopic features pose additional diagnostic challenges in dermatopathological practice. More over skin biopsies are of small size and diagnostic findings may not be present in the initial section. Hence, step sectioning may have added value as in adjunct in contemplating the final diagnosis. Objective: The study was aimed to evaluate the diagnostic utility of step sectioning in dermatopathology. Materials and Methods: A total of 478 skin biopsies were received over a period of 2 years from January 2015 to December 2016 at the Department of Pathology, JJMMC. Two prospective step sections (A2, A3) were cut at an interval of 50µm from the original section (A1). The findings were evaluated by two pathologists independently. The results were analysed and evaluated statistically. Results: Majority of cases (n= 453, 94.7%) were diagnostic. Out of these, many cases (n= 400, 83.6%) showed no additional findings on step sections. In a few cases (n= 32, 6.7%), step section provided additional findings which contributed to the diagnosis. There were some cases (n= 14, 3%) in which findings were noted only on step section leading to the diagnosis. Some cases (n=7, 1.46%) were such that the step sections changed the diagnosis made on original section. Conclusion: Step sectioning enhances the diagnostic accuracy of morphological assessment in ermatopathology practice.