Case Description
A 21-year old male presented in our Department due to an asymptomatic
nodule in the proximal fifth digit of the right hand, that had first
appeared 3 months prior to the referral. The lesion rapidly progressed
in size during the first 4 weeks and afterwards remained stable. The
clinical examination revealed a firm skin-coloured nodule, of
approximately 1.8 x 1.8 cm in size, with a central non-removable
keratinous plug (Figure 1A). The clinical diagnosis of keratoacanthoma
was made, and a biopsy was recommended for diagnosis confirmation. The
patient strongly refused the diagnostic biopsy and insisted on a non
surgical treatment. We therefore suggested a regimen of topical
imiquimod 5% cream under occlusion, for 5 consecutive days per week,
over a period of 4 weeks. 2 weeks after treatment initiation, a
prominent local inflammatory reaction could be documented, resulting in
crust formation and erosion (Figure 1B). 4 weeks after the completion of
treatment, the lesion was markedly flattened, until complete resolution
was achieved (Figure 1C).
Keratoacanthomas (KA) are epithelial tumours that present as rapidly
evolving nodules with a central hyperkeratotic plug, and occasionally
show signs of spontaneous regression [1]. The treatment of choice
for KAs is surgical excision, as it provides the advantage of complete
tumour removal in a short period of time [1-2]. However,
conservative therapeutic strategies are also to be considered,
especially when it comes to the management of KAs in visible areas with
a probability of cosmetic disfiguration, or when it comes to treating
patients with multiple KAs [2].
Keywords: Keratoacanthomas, imiquimod cream, epithelial tumour