Abstract
Purpose :
Keratoacanthoma is a cutaneous neoplasm that presents as a rapidly-growing tumor on the skin exposed to ultraviolet light. It appears as an exophytic, crater-like lesion filled with keratin. In the periocular lesion, eyelids are most often affected. Previous studies have shown that it may be difficult to clinically diagnose and to differentiate from Squamous Cell Carcinoma. The aim of this study is to highlight the histopathological features and epidemiological characteristics of a large series of keratoacanthoma in order to highlight the clinical and histopathological features of this particular tumor.
Methods :
A total of 49 cases were studied from the MUHC – McGill University Ocular Pathology & Translational Research Laboratory to determine the histopathological and epidemiological traits of keratoacanthoma. Data on age, sex, clinical, and histopathological features from patients between 1997 and 2022 were reviewed.
Results :
In the 49 cases, the average age was 65 years old, 60% of patients were male, 39% (N=19) were located in the upper eyelid, 39% (N=19) in the lower eyelid, 8% (N=4) in the canthus, 2% (N=1) in the eyebrow, and 12% (N=6) were unspecified. Histopathologically, all cases displayed a crater filled with keratin, accompanied by acanthosis and hyper and parakeratosis of the epidermis. In 19 cases (39%), mild to severe atypia up to carcinoma in situ (CIS) was found. In addition, there are mitotic figures in these cases with atypia. Extensive or focal areas of actinic damage were found in the superficial and deep dermis in all cases. In most cases, chronic, non-granulomatous inflammation was observed.
Conclusions :
To the best of our knowledge, this is the largest cohort of patients with keratoacanthoma of the eyelid. The finding of mild to severe atypia and CIS in a minority of cases did not indicate malignant transformation. Additional information on age of the patients and location of the legions may contribute to a correct clinical diagnosis.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.