Dermoscopy and Reflectance Confocal Microscopy in Actinic Keratosis, Intraepithelial Carcinoma, and Invasive Squamous Cell Carcinoma

March 2022 | Volume 21 | Issue 3 | Original Article | 259 | Copyright © March 2022


Published online February 28, 2022

Siliva A. Rstom MD MsC,a Beatrice M. Z. Abdalla MD,a Tatiana C. Blumetti MD PhD,b Leandro L. Matos MD PhD,c Maria Aparecida S. Pinhal MD PhD,a Francisco M. Paschoal MD PhDa

aABC Medical School, Santo Andre, Brazil
bA.C. Camargo Cancer Center, São Paulo, Brazil
cUniversity of São Paulo Medical School, São Paulo, Brazil

Abstract
Background: Patients with multiple actinic keratosis (AK), have pre-neosplastic abnormalities, constituting the sites of new tumors, this region is called the cancerization field. Due to the risk of malignant transformation, rigorous evaluation, follow-up, and treatment of the cancerization field is proposed. Recently, non-invasive diagnostic technologies such as confocal reflectance microscopy (RCM), detect AK, intraepithelial carcinomas (IEC), and SCC, without the need of repeated biopsies. There are few reports of the progression of AK assessed by dermatoscopy and RCM concomitantly.
Objectives: Define morphological patterns and clinical applicability of dermatoscopy and MCR examinations of the AK lesions and their degrees of progression to IEC and SCC.
Methods: A retrospective cross-sectional study of dermatoscopy and RCM examinations was performed in 30 patients with histopathological diagnosis of AK (20), IEC (6), and SCC (4).
Results: In the comparative analysis of the dermatoscopic features, erythema was present in 100% of the lesions, the red pseudo-network in 75% of the AK (P=0.007), and linear and irregular vessels in 90% of the lesions of IEC/SCC. In the RCM of AK, the most striking finding was the presence of atypical honeycomb in the spinous layer, but typical in the granular layer. While the IEC/SCC group presented irregular epidermal architecture and atypical honeycomb in all epider-mal layers, it also showed a higher prevalence of individual corneocytes and nucleated cells, cellular pleomorphism, and nuclear atypia in the dermal papillae, irregular vessels within papilla, and cells with bright edges and dark central nuclei in the dermis.
Conclusion: Dermoscopy and RCM may be considered as auxiliary methods for assessing lesions resulting from ke-ratinocyte atypia. The results of this study are consistent with published studies and it was possible to propose, with literature support, a model of progression of AK to IEC and SCC.

J Drugs Dermatol. 2022;21(3):259-268. doi:10.36849/JDD.5086

INTRODUCTION

Squamous cell carcinoma (SCC) represents the second most common skin cancer in Europe.1,2 This may arise from precancerous lesions such as actinic keratosis (AK), actinic cheilitis, oral leukoplakia, and chronic radiodermatitis. Although the risk of progression from an AK to an invasive SCC is low, it is estimated that 60% to 97% of the SCCs originates from AKs.3,4

AK is a pre-malignant lesion that affects more than 60% of the elderly population in Europe.1 Once developed, AK can follow different evolutionary courses, from spontaneous involution, stable persistence, to progression into intraepithelial carcinoma (IEC) or invasive SCC. Although the actual risk of progression cannot be exactly measured, rates can vary from 5 to 20% in 10 to 25 years.5,6,7,8,9 IEC can progress to invasive SCC in 3 to 5% of cases10 with a potential risk for metastasis of up to 10%.11

Patients with multiple AKs in a particular region have this affected area called the cancerization field. Cancerization field is a region containing subclinical and multifocal pre-neoplastic abnormalities with genetic mutations that may constitute the site of multiple primary tumors.7,12,13
Close Menu