Recurrent Keratoacanthoma

Isabella Kest,Nahla Shihab,Kaylee Fisher,Mark Lebwohl

doi:10.25251/skin.4.4.17

Isabella Kest, Nahla Shihab + Show 2 more

Open Access

https://doi.org/10.25251/skin.4.4.17

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Abstract

Keratoacanthoma (KA) is a cutaneous squamoproliferative tumor with multiple etiologies suggested. KA can have a benign course, resolving spontaneously, but because it can rarely metastasize, some consider it to be a form of squamous cell carcinoma (SCC). We report a 65-year-old Caucasian male diagnosed with KA in the conch of the left ear, which initially resolved with intralesional methotrexate, but eventually recurred.

Highlights

Keratoacanthoma (KA) is a cutaneous squamoproliferative tumor that typically presents as a 1 to 2 cm dome shaped nodule with central keratosis.[1]
KA is often characterized by phases of rapid growth, lesion stability and rapid involution
KA is often confused with squamous cell carcinoma (SCC) or even regarded as a variant of SCC, because of the similarity in histopathological appearance.[3,4]

Summary

INTRODUCTION

Keratoacanthoma (KA) is a cutaneous squamoproliferative tumor that typically presents as a 1 to 2 cm dome shaped nodule with central keratosis.[1]. Because of histopathological overlap with squamous cell carcinoma, surgical excision with clear margins is often recommended. Other modalities have been used successfully including: topical 5% imiquimod cream, topical 5% 5-flourouacil (5-FU) cream, intralesional bleomycin, intralesional methotrexate, intralesional 5-FU, and oral isotretinoin.[2] Intralesional methotrexate (MTX) injections have proven to be an effective treatment option for KAs.[2] MTX is a folic acid analogue that permanently binds to dihydrofolate reductase and blocks the formation of tetrahydrofolate which prevents the synthesis of the purine nucleotide thymidine, thereby leading to a halt in DNA synthesis.[5] It is recommended that MTX injections be used as the first line of treatment when KAs are presented in cosmetically sensitive areas and in elderly patients.[5]. Cases that require extensive surgical reconstruction, in sensitive sites such as the ear.[5,7]

DISCUSSION

CONCLUSION