Analysis of the consistency of doctors’ opinions in the assessment of dermatoscopic images of actinic keratosis, Bowen’s disease, keratoacanthoma and squamous cell cancer

Background. Squamous cell skin cancer (SCSC) is the most dangerous tumor of all non-melanocytic skin neoplasms due to its aggressive course with destructive growth and frequent metastasis. Another characteristic feature of SCSC is the presence of precancerous conditions such as actinic keratosis, arsenic keratosis and PUVA-keratosis. In the gradual increase in the degree of keratinocyte dysplasia to the development of invasive forms of skin malignancies, the following continuum of diseases can be distinguished: actinic keratosis — Bowen’s disease — keratoacanthoma — SCSC. Dermatoscopic signs of each of the listed nosologies can also occur in other diseases of this chain, which can complicate diagnosis and lead to erroneous patient management tactics.

Aim. To determine the consistency of dermatologists’ opinions in assessing dermatoscopic images of actinic keratosis, Bowen’s disease, keratoacanthoma and SCSC, depending on work experience.

Methods. The study was conducted on the basis of the Scientific and Practical Center for the Diagnosis and Treatment of Skin Tumors of the Federal State Budgetary Educational Institution “PIMU” of the Ministry of Health of the Russian Federation. Based on the literature data, we compiled a generalized list of possible dermatoscopic signs of actinic keratosis, Bowen’s disease, keratoacanthoma, SCSC and analyzed dermatoscopic images of 85 elements of actinic keratosis, 28 — of Bowen’s disease, 10 — of keratoacanthoma and 24 — of SCSC. 10 dermatovenerologists participated in the study, half of whom (Group 1) had experience in the field of dermatoscopy for more than 4 years, and the other half (Group 2) — for less than 4 years.

Results. The study reveals statistically significant deviations in the frequencies of dermatoscopic signs between the two groups of specialists when analyzing images of actinic keratosis and Bowen’s disease. Differences in the frequency of detection of keratoacanthoma and SCSC signs between specialists with more than 4 years of experience in the field of dermatoscopy and less than 4 years’ experience have not been found.

Conclusion. Taking into account the average number of signs, the statistically justified result of the analysis is the inference that the average group frequencies in Group 1 and Group 2 are equal. The conclusion is that the opinions of specialists in the field of dermatoscopy are highly consistent, regardless of work experience. This indicates the high diagnostic value of the method, despite its subjective nature.