RESUMEN
Actinic keratosis (AK) and field cancerization are increasing health problems insufficiently diagnosed by primary care physicians. The objective of this study was to assess the validity and reliability of teledermatology (TD) and teledermoscopy in the diagnosis of AK and field cancerization in a gatekeeper healthcare model. A prospective diagnostic test evaluation was done to assess the diagnostic concordance, accuracy, and performance parameters and the interobserver and intraobserver concordances of TD and teledermoscopy compared with dermatologists' face-to-face evaluation or histopathology. A total of 636 patients with 1,000 keratotic skin lesions were included. TD diagnostic concordance for AK and field cancerization evaluation was very high and superior to primary care physicians' diagnosis (92.4% vs. 62.4% and 96.7% vs. 51.8%, P < 0.001). TD sensitivity, specificity, and positive and negative predictive values for AK diagnosis and field cancerization were high (range = 82.2-95.0) and better than primary care physicians' diagnosis. Teledermoscopy yielded better results in diagnostic concordance, performance parameters, and AK subtypes. Intraobserver and interobserver agreement was >0.83. TD and, to a greater extent, teledermoscopy may be valid and reliable tools for the diagnosis of AK and field cancerization and may improve diagnosis and correct allocation and management in gatekeeper healthcare systems. It can be an alternative tool to training primary care physicians in direct diagnosis of these lesions.