Case 15: Squamous Cell Carcinoma in Situ and Seborrheic Keratosis

This image shows the collision of two entities

1️⃣ Pigmented seborrheic keratosis (L)

2️⃣ Squamous cell carcinoma in situ (R)

Note: While there is definitely atypia on both sides of the image in the collision of these two entities, the left side better shows the features of an SK, while the right side better shows the full-thickness atypia of SCCIS.

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