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Updated: Oct 27, 2025

Implantation and Evaluation of Melanoma in the Murine Choroid via Optical Coherence Tomography
Published on: December 2, 2022
A Wolf in Sheep's Clothing: Collision of Melanoma and Keratoacanthoma
Matthias Walther1, Sandra Falkvoll1, Sebastian Leibl2
1Skinmed-Clinic for Dermatology, 5000 Aarau, Switzerland.
Abstract:
Collision tumors consisting of melanoma and squamous cell carcinoma are very rare. We present the case of a deceptive hyperkeratotic nodule on the forearm of a 72-year-old woman, which clinically appeared to be a squamous cell carcinoma, keratoacanthoma type. Histological examination surprisingly revealed a coexisting epithelioid melanoma. Thus, this case report shows the importance of an early histopathological and immunohistochemical workup to prevent unnecessary diagnostic and therapeutic delay with negative effects on prognosis.
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