Longitudinal pilot study examining the effect of punch biopsy on equine sarcoid growth dynamics.

The research investigated the impact of a single punch biopsy in the growth dynamics of equine sarcoid tumors, revealing that changes to the tumor are not consistently negative or positive post-biopsy.

Objective and Methodology

• The main objective of the study was to understand the effect of a single punch biopsy on the growth dynamics of equine sarcoid tumors, specifically, changes in their thickness, area, circumference, viral load (VL), and Visual Analog Scale (VAS score).
• This longitudinal pilot investigation was conducted on eleven sarcoids found in six client-owned horses with various sarcoid classifications.
• To have a comprehensive view, the researchers monitored the growth dynamics of the tumors twelve weeks prior to and twenty-four weeks after the punch biopsy.
• They utilized linear mixed-effect models to measure the change in growth dynamics caused by a single punch biopsy.
• Additionally, Spearman’s rank correlation coefficient (SRCC) was calculated to determine correlations with the number of weeks before and after the biopsy procedure.

Results

• The post-biopsy changes in thickness, area, circumference, VL and VAS were statistically significant for all parameters except VL. However, none of these parameters were found to consistently increase after the biopsy intervention.
• In terms of the VL, two of the eleven sarcoids showed significant strong correlations. In sarcoid 6, the VL increased pre-biopsy (r = -0.66, p < 0.05) and greatly increased post-biopsy (r = 0.81, p < 0.001). Whereas in sarcoid 8, the VL significantly increased pre-biopsy (r = 0.85, p 0.05).

Conclusion

• Contrary to the prevalent fear of sarcoid deterioration post-biopsy, the results suggest that lesion progression after biopsy is not a universal concept and can have different outcomes—either deterioration or improvement—over a 24-week period.
• However, the researchers emphasize the need for further clinical studies with larger sample sizes to achieve a definitive conclusion on this matter.