Prognostic significance of tumor budding in cutaneous squamous cell carcinoma

To the Editor: We read with interest the article by Gonzalez-Guerrero et al1 reporting the prognostic significance of tumor buds in cutaneous squamous cell carcinoma (cSCC). The results of this study confirm and complement the results of 2 similar investigations published previously on the same topic,2,3 even though the methodology of these 3 studies was not identical. In our study,2 we compared 31 aggressive cSCCs, defined as tumors with subsequent local recurrences or metastases, with 21 nonaggressive cSCCs (which had been obtained from the same group of organ-graft recipients) and counted the number of tumor buds (defined as groups of 1-5 tumor cells) on 5 adjacent microscopic hot-spot fields at the invasive tumor front.