CLINICAL-MORPHOLOGICAL FEATURES AND NEW ASPECTS OF KERATOACANTHOMA TREATMENT:NARRATIVE REVIEW

Keratoacanthoma (KA) is a well-differentiated (G1) epithelial tumor characterized by rapid growth, low malignant potential, and a minimal risk of metastasis. The biological behavior of KA remains a subject of scientific debate. The main challenge lies in its significant clinical and histopathological similarity to cutaneous squamous cell carcinoma (cSCC).Clinically, KA is usually easy to recognize because of its characteristic appearance. It presents as a rapidly growing, dome-shaped nodule with a central crater-like depression filled with keratinous material. The tumor typically progresses through three sequential stages—growth, stabilization, and spontaneous regression. The entire cycle usually lasts 3–9 months and often culminates in the formation of an atrophic scar. Histopathological examination remains the only reliable method for distinguishing KA from cSCC. Accurate assessment requires an excisional or deep incisional biopsy, as superficial sampling techniques do not adequately demonstrate the overall architecture of the lesion. The tumor is believed to originate from the hair follicle. The key dermoscopic features shared by both KA and cSCC include white circles, central keratin accumulation, white structureless areas, and linear, branched, hairpin, and glomerular vessels. Because the dermoscopic appearance of KA closely resembles that of cSCC, a definitive diagnosis can only be established by histopathological examination. Current treatment strategies should be individualized according to lesion characteristics, anatomical location, growth pattern, histopathological findings, and patient-related factors. Surgical excision remains the preferred approach when malignancy cannot be excluded or when aggressive clinical features are present. In selected patients, tissue-preserving modalities—including intralesional methotrexate, intralesional 5-fluorouracil, cryotherapy, laser-based techniques, and other conservative approaches—may also be considered. In this narrative review, we summarize the clinical, dermoscopic, and histopathological features of KA and discuss contemporary therapeutic strategies. The analysis is complemented by the authors’ clinical experience and dermoscopic observations from routine dermatological practice, highlighting the practical value of dermoscopy in lesion assessment, the selection of representative biopsy sites, and individualized treatment planning.