DR. KAUSTUBH MULAY

DR. ROLIKA BANSAL, DR. SANTOSH G. HONAVAR

Abstract

Background

Tumor size is an important prognostic factor in uveal melanoma, but the AJCC staging system does not mandate a specific measurement method. Formalin fixation can cause tumor shrinkage. We conducted this study to evaluate the effect of overnight formalin fixation on tumor size and hence, T-category

Method

We enrolled patients who underwent enucleation for uveal melanoma. Tumor size (length, thickness and height) was measured immediately and after overnight formalin-fixation. The results were compared.

Results

Twenty-six patients (M:F=2.7:1) were included. Average decreases in length, thickness and height after formalin-fixation were 0.87mm (6.57%), 0.62mm (6.22%) and 0.52mm (7.5%). T-category changed in 19.2% (n=5) post formalin-fixation.

Conclusion

Formalin Fixation shrinks Uveal Melanoma and may cause migration to a lower T-category. For accurate tumor staging, we recommend tumor size measurements to be performed on fresh specimens instead of after formalin-fixation.