A recent study demonstrates the probable utility of noninvasive diagnostic methods such as dermoscopy and confocal reflectance microscopy (RCM) in minimizing biopsy use in predicting the progression of actinic keratosis (AK) to carcinoma.

Silva ARstom from ABC Medical School in Santo Andre, Brazil, and colleagues described that patients with multiple AK have preneoplastic abnormalities including the sites of new tumors, which is known as the cancerization field. 

Since these locations have an increased likelihood of developing into malignancy, the researchers proposed that rigorous evaluation, follow-up and treatment of these regions may be necessary. Nevertheless, they believed that noninvasive diagnostic methods like RCM may have the ability to substitute repeated biopsies in detecting detect AK, intraepithelial carcinoma (IEC) and squamous cell carcinoma (SCC).

Currently, little data describe the nature of AK progression as evaluated by concomitant dermoscopy and RCM.

In a recent retrospective cross-sectional study, the researchers defined morphological patterns and clinical relevancy of dermoscopy and RCM assessments of AK lesions and the extent to which they indicate progression to IEC and SCC. The analysis contained 30 patients, of which 20 had been diagnosed with AK, 6 with IEC and 4 with SCC.

Comparative analysis of dermatoscopic features revealed the presence of erythema in all lesions, while three-quarters of lesions showed the red pseudo-network of AK and linear and irregular vessels in 90% of IEC/SCC lesions.

The researchers emphasized the presence of an atypical honeycomb in the spinous layer as a principal observation from the RCM of AK, which was typical in the granular layer.

In the IEC/SCC group, irregular epidermal architecture and atypical honeycomb were seen in all epidermal layers. Additionally, these malignancies revealed a higher prevalence of individual corneocytes and nucleated cells, cellular pleomorphism and nuclear atypia dermal papillae. The researchers also marked irregular vessels within the papilla of the IEC/SCC patients, along with cells having bright edges and dark central nuclei in the dermis.

These findings prompted the group to conclude that both dermoscopy and RCM may be used as auxiliary methods for assessing lesions resulting from keratinocyte atypia.

Source: Volansky R. Dermoscopy, confocal reflectance microscopy may predict carcinoma in actinic keratosis. March 24, 2022. Available from:https://www.healio.com/news/dermatology/20220323/dermoscopy-confocal-reflectance-microscopy-may-predict-carcinoma-in-actinic-keratosis