Skin punch biopsy sectioning: before or after tissue processing?

Background: We intended to study whether there is a meaningful difference in microscopic examination between dividing a biopsy section into two equal parts before tissue processing (first method) or after (second method).

Methods: A total of 400 cases were included in the study. Punch biopsies (PB) were cut into two pieces using the first method in 200 cases and just before paraffin embedding in another 200 cases using the second method. We microscopically evaluated the epidermal mesh view, the presence of a cross-cut hair follicle and bow shape because of epidermal angling, the presence of two pieces on the slide and if there was a difference of >2 mm between the parts, and the number of new sections and new slides.

Results: Cross-cut hair follicle (p = 0.018), epidermal mesh view (p = 0.036), difference of >2 mm between the parts (p = 0.008), the number of new sections (p < 0.001) and new slides (p < 0.001) were considerably higher when the first method was used compared with the second method. The presence of two pieces was less (p < 0.001) when using the first method.

Conclusions: We noted a meaningful difference in the quality of microscopic evaluation between the first and second methods. Better sections were obtained with the second method. In addition, the decrease in the number of new slides will reduce workload, archival work and cost.